Merge pull request #296 from kerberos-io/feature/upgrade-tus-chunk-size

feature/upgrade-tus-chunk-size

.github/workflows/pr-description.yaml

@@ -2,25 +2,16 @@ name: Autofill PR description
 
 on: pull_request
 
-env:
-  ORGANIZATION: uugai
-  PROJECT: ${{ github.event.repository.name }}
-  PR_NUMBER: ${{ github.event.number }}
-  
 jobs:
   openai-pr-description:
-    runs-on: ubuntu-22.04
-
-    steps:
-      - uses: actions/checkout@v4
-      - name: Autofill PR description if empty using OpenAI
-        uses: cedricve/azureopenai-pr-description@master
-        with:
-          github_token: ${{ secrets.TOKEN }}
-          openai_api_key: ${{ secrets.OPENAI_API_KEY }}
-          azure_openai_api_key: ${{ secrets.AZURE_OPENAI_API_KEY }}
-          azure_openai_endpoint: ${{ secrets.AZURE_OPENAI_ENDPOINT }}
-          azure_openai_version: ${{ secrets.AZURE_OPENAI_VERSION }}
-          openai_model: ${{ secrets.OPENAI_MODEL }}
-          pull_request_url: https://pr${{ env.PR_NUMBER }}.api.kerberos.lol
-          overwrite_description: true
+    uses: uug-ai/workflows/.github/workflows/pr-description.yml@main
+    with:
+      pr_number: ${{ github.event.number }}
+      pull_request_url: ""
+      overwrite_description: true
+    secrets:
+      TOKEN: ${{ secrets.TOKEN }}
+      AZURE_OPENAI_API_KEY: ${{ secrets.AZURE_OPENAI_API_KEY }}
+      OPENAI_MODEL: ${{ secrets.OPENAI_MODEL }}
+      AZURE_OPENAI_ENDPOINT: ${{ secrets.AZURE_OPENAI_ENDPOINT }}
+      AZURE_OPENAI_VERSION: ${{ secrets.AZURE_OPENAI_VERSION }}

.github/workflows/release-bump.yml

@@ -0,0 +1,168 @@
+name: Bump release
+
+on:
+  workflow_dispatch:
+    inputs:
+      bump:
+        description: "Which part of the version to bump"
+        required: true
+        default: patch
+        type: choice
+        options:
+          - major
+          - minor
+          - patch
+
+permissions:
+  contents: write
+
+env:
+  REPO: kerberos/agent
+
+jobs:
+  # Determine the next version, create the GitHub release and expose the tag.
+  bump-release:
+    uses: uug-ai/workflows/.github/workflows/release-bump.yml@main
+    with:
+      bump: ${{ github.event.inputs.bump }}
+    secrets: inherit
+
+  # Publish the platform image to the uug-ai GitHub Container Registry
+  # (ghcr.io/uug-ai/agent-platform).
+  release:
+    needs: bump-release
+    uses: uug-ai/workflows/.github/workflows/release-create.yml@main
+    with:
+      organization: uug-ai
+      project: ${{ github.event.repository.name }}
+      tag: ${{ needs.bump-release.outputs.tag }}
+      docker_context: "."
+      create_gitops_pr: false
+      runner_matrix: >-
+        [
+          {"architecture":"amd64","runner":"ubuntu-24.04"},
+          {"architecture":"arm64","runner":"ubuntu-24.04-arm"}
+        ]
+    secrets: inherit
+
+  # Everything below mirrors the agent's own release-create.yml pipeline and
+  # publishes the multi-arch image to the kerberos/agent Docker Hub repo, driven
+  # by the freshly bumped tag instead of a `release: created` event.
+  build-amd64:
+    needs: bump-release
+    runs-on: ubuntu-24.04
+    permissions:
+      contents: write
+    strategy:
+      matrix:
+        architecture: [amd64]
+    steps:
+      - name: Login to DockerHub
+        uses: docker/login-action@v2
+        with:
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+      - name: Checkout
+        uses: actions/checkout@v3
+      - uses: benjlevesque/short-sha@v2.1
+        id: short-sha
+        with:
+          length: 7
+      - name: Run Build
+        run: |
+          docker build --provenance=false --build-arg VERSION=${{ needs.bump-release.outputs.tag }} -t ${{matrix.architecture}} .
+          CID=$(docker create ${{matrix.architecture}})
+          docker cp ${CID}:/home/agent ./output-${{matrix.architecture}}
+          docker rm ${CID}
+      - name: Strip binary
+        run: tar -cf agent-${{matrix.architecture}}.tar -C output-${{matrix.architecture}} . && rm -rf output-${{matrix.architecture}}
+      - name: Build and push Docker image
+        run: |
+          docker tag ${{matrix.architecture}} $REPO-arch:arch-${{matrix.architecture}}-${{ needs.bump-release.outputs.tag }}
+          docker push $REPO-arch:arch-${{matrix.architecture}}-${{ needs.bump-release.outputs.tag }}
+      - name: Upload artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: agent-${{matrix.architecture}}.tar
+          path: agent-${{matrix.architecture}}.tar
+
+  build-arm64:
+    needs: bump-release
+    runs-on: ubuntu-24.04-arm
+    permissions:
+      contents: write
+    strategy:
+      matrix:
+        architecture: [arm64]
+    steps:
+      - name: Login to DockerHub
+        uses: docker/login-action@v2
+        with:
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+      - name: Checkout
+        uses: actions/checkout@v3
+      - uses: benjlevesque/short-sha@v2.1
+        id: short-sha
+        with:
+          length: 7
+      - name: Run Build
+        run: |
+          docker build --provenance=false --build-arg VERSION=${{ needs.bump-release.outputs.tag }} -t ${{matrix.architecture}} -f Dockerfile.arm64 .
+          CID=$(docker create ${{matrix.architecture}})
+          docker cp ${CID}:/home/agent ./output-${{matrix.architecture}}
+          docker rm ${CID}
+      - name: Strip binary
+        run: tar -cf agent-${{matrix.architecture}}.tar -C output-${{matrix.architecture}} . && rm -rf output-${{matrix.architecture}}
+      - name: Build and push Docker image
+        run: |
+          docker tag ${{matrix.architecture}} $REPO-arch:arch-${{matrix.architecture}}-${{ needs.bump-release.outputs.tag }}
+          docker push $REPO-arch:arch-${{matrix.architecture}}-${{ needs.bump-release.outputs.tag }}
+      - name: Upload artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: agent-${{matrix.architecture}}.tar
+          path: agent-${{matrix.architecture}}.tar
+
+  create-manifest:
+    runs-on: ubuntu-24.04
+    needs: [bump-release, build-amd64, build-arm64]
+    steps:
+      - name: Login to DockerHub
+        uses: docker/login-action@v2
+        with:
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+      - name: Create and push multi-arch manifest
+        run: |
+          docker manifest create $REPO:${{ needs.bump-release.outputs.tag }} \
+            $REPO-arch:arch-amd64-${{ needs.bump-release.outputs.tag }} \
+            $REPO-arch:arch-arm64-${{ needs.bump-release.outputs.tag }}
+          docker manifest push $REPO:${{ needs.bump-release.outputs.tag }}
+      - name: Create and push latest manifest
+        run: |
+          docker manifest create $REPO:latest \
+            $REPO-arch:arch-amd64-${{ needs.bump-release.outputs.tag }} \
+            $REPO-arch:arch-arm64-${{ needs.bump-release.outputs.tag }}
+          docker manifest push $REPO:latest
+
+  create-release:
+    runs-on: ubuntu-24.04
+    needs: [bump-release, build-amd64, build-arm64]
+    permissions:
+      contents: write
+    steps:
+      - name: Download all artifacts
+        uses: actions/download-artifact@v4
+      - name: Create a release
+        uses: ncipollo/release-action@v1
+        with:
+          latest: true
+          allowUpdates: true
+          name: ${{ needs.bump-release.outputs.tag }}
+          tag: ${{ needs.bump-release.outputs.tag }}
+          generateReleaseNotes: false
+          omitBodyDuringUpdate: true
+          artifacts: "agent-*.tar/agent-*.tar"
+
+  

.gitignore

@@ -14,5 +14,7 @@ machinery/test*
 machinery/init-dev.sh
 machinery/.env.local
 machinery/vendor
+machinery/go.work
+machinery/go.work.sum
 deployments/docker/private-docker-compose.yaml
 video.mp4

.vscode/launch.json

@@ -18,6 +18,9 @@
             ],
             "envFile": "${workspaceFolder}/machinery/.env.local",
             "buildFlags": "--tags dynamic",
+            "env": {
+                "GOWORK": "off"
+            },
         },
         {
             "name": "Launch React",

Dockerfile

@@ -4,6 +4,11 @@ ARG VERSION=0.0.0
 FROM kerberos/base:${BASE_IMAGE_VERSION} AS build-machinery
 LABEL AUTHOR=uug.ai
 
+# Re-declare VERSION inside this stage so the value passed via
+# `--build-arg VERSION=...` (e.g. the release tag) is available below.
+# ARGs declared before the first FROM are not visible inside build stages.
+ARG VERSION
+
 ENV GOROOT=/usr/local/go
 ENV GOPATH=/go
 ENV PATH=$GOPATH/bin:$GOROOT/bin:/usr/local/lib:$PATH
@@ -35,7 +40,9 @@ RUN cat /go/src/github.com/kerberos-io/agent/machinery/version
 
 RUN cd /go/src/github.com/kerberos-io/agent/machinery && \
 	go mod download && \
-	VERSION=$(cd /go/src/github.com/kerberos-io/agent && git describe --tags --always 2>/dev/null || echo "${VERSION}") && \
+	if [ -z "${VERSION}" ] || [ "${VERSION}" = "0.0.0" ]; then \
+		VERSION=$(cd /go/src/github.com/kerberos-io/agent && git describe --tags --always 2>/dev/null || echo "0.0.0"); \
+	fi && \
 	go build -tags timetzdata,netgo,osusergo --ldflags "-s -w -X github.com/kerberos-io/agent/machinery/src/utils.VERSION=${VERSION} -extldflags '-static -latomic'" main.go && \
 	mkdir -p /agent && \
 	mv main /agent && \
@@ -60,7 +67,7 @@ RUN cp -r /agent ./
 
 RUN /dist/agent/main version
 
-FROM node:18.14.0-alpine3.16 AS build-ui
+FROM node:22-alpine AS build-ui
 
 RUN apk update && apk upgrade --available && sync
 

Dockerfile.arm64

@@ -4,6 +4,11 @@ ARG VERSION=0.0.0
 FROM kerberos/base:${BASE_IMAGE_VERSION} AS build-machinery
 LABEL AUTHOR=uug.ai
 
+# Re-declare VERSION inside this stage so the value passed via
+# `--build-arg VERSION=...` (e.g. the release tag) is available below.
+# ARGs declared before the first FROM are not visible inside build stages.
+ARG VERSION
+
 ENV GOROOT=/usr/local/go
 ENV GOPATH=/go
 ENV PATH=$GOPATH/bin:$GOROOT/bin:/usr/local/lib:$PATH
@@ -35,7 +40,9 @@ RUN cat /go/src/github.com/kerberos-io/agent/machinery/version
 
 RUN cd /go/src/github.com/kerberos-io/agent/machinery && \
 	go mod download && \
-	VERSION=$(cd /go/src/github.com/kerberos-io/agent && git describe --tags --always 2>/dev/null || echo "${VERSION}") && \
+	if [ -z "${VERSION}" ] || [ "${VERSION}" = "0.0.0" ]; then \
+		VERSION=$(cd /go/src/github.com/kerberos-io/agent && git describe --tags --always 2>/dev/null || echo "0.0.0"); \
+	fi && \
 	go build -tags timetzdata,netgo,osusergo --ldflags "-s -w -X github.com/kerberos-io/agent/machinery/src/utils.VERSION=${VERSION} -extldflags '-static -latomic'" main.go && \
 	mkdir -p /agent && \
 	mv main /agent && \
@@ -60,7 +67,7 @@ RUN cp -r /agent ./
 
 RUN /dist/agent/main version
 
-FROM node:18.14.0-alpine3.16 AS build-ui
+FROM node:22-alpine AS build-ui
 
 RUN apk update && apk upgrade --available && sync
 

README.md

@@ -65,6 +65,7 @@ There are a myriad of cameras out there (USB, IP and other cameras), and it migh
 
 ### Contributing
 
+1. [Security vulnerability reporting](#security-vulnerability-reporting)
 1. [Contribute with Codespaces](#contribute-with-codespaces)
 2. [Develop and build](#develop-and-build)
 3. [Building from source](#building-from-source)
@@ -230,9 +231,9 @@ Next to attaching the configuration file, it is also possible to override the co
 | `AGENT_MQTT_PASSWORD`                       | Password of the MQTT broker.                                                                    | ""                             |
 | `AGENT_REALTIME_PROCESSING`                 | If `AGENT_REALTIME_PROCESSING` set to `true`, the agent will send key frames to the topic       | ""                             |
 | `AGENT_REALTIME_PROCESSING_TOPIC`           | The topic to which keyframes will be sent in base64 encoded format.                             | ""                             |
-| `AGENT_STUN_URI`                            | When using WebRTC, you'll need to provide a STUN server.                                        | "stun:turn.kerberos.io:8443"   |
+| `AGENT_STUN_URI`                            | When using WebRTC, you'll need to provide a STUN server.                                        | "stun:turn-fra1.kerberos.io:3478"|
 | `AGENT_FORCE_TURN`                          | Force using a TURN server, by generating relay candidates only.                                 | "false"                        |
-| `AGENT_TURN_URI`                            | When using WebRTC, you'll need to provide a TURN server.                                        | "turn:turn.kerberos.io:8443"   |
+| `AGENT_TURN_URI`                            | When using WebRTC, you'll need to provide a TURN server.                                        | "turn:turn-fra1.kerberos.io:3478"|
 | `AGENT_TURN_USERNAME`                       | TURN username used for WebRTC.                                                                  | "username1"                    |
 | `AGENT_TURN_PASSWORD`                       | TURN password used for WebRTC.                                                                  | "password1"                    |
 | `AGENT_CLOUD`                               | Store recordings in Kerberos Hub (s3), Kerberos Vault (kstorage), or Dropbox (dropbox).         | "s3"                           |
@@ -301,6 +302,10 @@ If we talk about video encoders and decoders (codecs) there are 2 major video co
 
 Conclusion: depending on the use case you might choose one over the other, and you can use both at the same time. For example you can use H264 (main stream) for livestreaming, and H265 (sub stream) for recording. If you wish to play recordings in a cross-platform and cross-browser environment, you might opt for H264 for better support.
 
+## Security vulnerability reporting
+
+If you found a potential security vulnerability, please use the private channels described in [SECURITY.md](SECURITY.md). Avoid opening public GitHub issues for sensitive findings.
+
 ## Contribute with Codespaces
 
 One of the major blockers for letting you contribute to an Open Source project is to set up your local development machine. Why? Because you might already have some tools and libraries installed that are used for other projects, and the libraries you would need for Kerberos Agent, for example FFmpeg, might require a different version. Welcome to dependency hell...

SECURITY.md

@@ -0,0 +1,40 @@
+# Security Policy
+
+## Supported Versions
+
+We only provide security fixes for the latest release series on the `master` branch.
+
+## Reporting a Vulnerability
+
+Please do **not** open a public GitHub issue for potential security vulnerabilities.
+
+Use one of the private channels below:
+
+1. Preferred: GitHub private vulnerability reporting
+   - https://github.com/kerberos-io/agent/security/advisories/new
+2. Fallback: Email
+   - support@kerberos.io
+   - Optional CC: support@uug.ai
+
+Please include:
+
+- A short summary and impact.
+- Reproduction steps or proof of concept.
+- Affected version(s), commit hash, or deployment details.
+- Any proposed mitigation/workaround.
+- Your preferred attribution name.
+
+For faster triage, use this subject format in email:
+
+`[Security][Kerberos Agent] <short title>`
+
+## Response Expectations
+
+- Acknowledgement target: within 3 business days.
+- Triage/update target: within 7 business days after acknowledgement.
+
+If you do not receive a response in time, please resend your report and include your original timestamp.
+
+## Disclosure and Credits
+
+We follow coordinated disclosure. After a fix is available, we will credit reporters unless they prefer to stay anonymous.

machinery/.env

@@ -27,5 +27,12 @@ AGENT_KERBEROSVAULT_SECONDARY_DIRECTORY=
 AGENT_KERBEROSVAULT_SECONDARY_ACCESS_KEY=
 AGENT_KERBEROSVAULT_SECONDARY_SECRET_KEY=
 
+# Resumable (tus) uploads to Kerberos Vault are enabled by default.
+# Set to true to fall back to the legacy single-shot POST /storage upload.
+#AGENT_DISABLE_RESUMABLE_UPLOAD=true
+# Bytes sent per PATCH request (default 1 MiB = 1048576). 0 disables chunking
+# and sends the whole file in a single PATCH.
+AGENT_TUS_CHUNK_SIZE_BYTES=1048576
+
 # Open telemetry tracing endpoint
 OTEL_EXPORTER_OTLP_ENDPOINT=

machinery/README.md

@@ -22,4 +22,8 @@ https://brianmacdonald.github.io/Ethonate/address#0xf4a759C9436E2280Ea9cdd23d314
 
 [**Docker Hub**](https://hub.docker.com/r/kerberos/agent) | [**Documentation**](https://doc.kerberos.io) | [**Website**](https://kerberos.io)
 
-Kerberos Open source (v3) is a cutting edge video surveillance management system made available as Open Source under the MIT License. This means that all the source code is available for you or your company, and you can use, transform and distribute the source code; as long you keep a reference of the original license. Kerberos Open Source (v3) can be used for commercial usage (which was not the case for v2). Read more [about the license here](LICENSE).
+Kerberos Open source (v3) is a cutting edge video surveillance management system made available as Open Source under the MIT License. This means that all the source code is available for you or your company, and you can use, transform and distribute the source code; as long you keep a reference of the original license. Kerberos Open Source (v3) can be used for commercial usage (which was not the case for v2). Read more [about the license here](LICENSE).
+
+## Security reporting
+
+For sensitive vulnerabilities, use private disclosure channels documented in [../SECURITY.md](../SECURITY.md).

machinery/cmd/mp4analyze/main.go

@@ -0,0 +1,636 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"sort"
+
+	"github.com/Eyevinn/mp4ff/avc"
+	mp4ff "github.com/Eyevinn/mp4ff/mp4"
+)
+
+func main() {
+	fromFlag := flag.Int64("from", -1, "start of the detailed inspection window (track timescale units); default auto-detects the largest keyframe gap")
+	toFlag := flag.Int64("to", -1, "end of the detailed inspection window (track timescale units); default auto-detected")
+	flag.Parse()
+	if flag.NArg() < 1 {
+		fmt.Println("usage: mp4analyze [-from N] [-to N] <file.mp4>")
+		os.Exit(1)
+	}
+	f, err := os.Open(flag.Arg(0))
+	if err != nil {
+		panic(err)
+	}
+	defer f.Close()
+	parsed, err := mp4ff.DecodeFile(f)
+	if err != nil {
+		panic(err)
+	}
+
+	// Movie-level info
+	if parsed.Init != nil && parsed.Init.Moov != nil {
+		moov := parsed.Init.Moov
+		fmt.Printf("ftyp/moov present. timescale(mvhd)=%d duration(mvhd)=%d\n",
+			moov.Mvhd.Timescale, moov.Mvhd.Duration)
+		for _, trak := range moov.Traks {
+			ts := trak.Mdia.Mdhd.Timescale
+			fmt.Printf("  trak id=%d handler=%s mdhd.timescale=%d mdhd.duration=%d\n",
+				trak.Tkhd.TrackID, trak.Mdia.Hdlr.HandlerType, ts, trak.Mdia.Mdhd.Duration)
+		}
+	} else {
+		fmt.Println("no Init/Moov (pure fragmented stream?)")
+	}
+
+	// sidx vs actual segment layout. MSE players use sidx to map presentation
+	// time -> byte ranges; if sidx references disagree with the real segment
+	// sizes/durations (e.g. after an early/short flush) the player fetches the
+	// wrong bytes and fails to decode — a failure that "heals" on seek.
+	fmt.Println("=== sidx references vs actual segments ===")
+	var sidxRefs []mp4ff.SidxRef
+	for _, c := range parsed.Children {
+		if s, ok := c.(*mp4ff.SidxBox); ok {
+			fmt.Printf("  sidx: timescale=%d earliestPresTime=%d firstOffset=%d refCount=%d anchor(after sidx)=%d\n",
+				s.Timescale, s.EarliestPresentationTime, s.FirstOffset, len(s.SidxRefs), s.AnchorPoint)
+			sidxRefs = s.SidxRefs
+		}
+	}
+	// Actual segment sizes (styp+moof+mdat) and fragment durations.
+	type segInfo struct {
+		size uint64
+		dur  uint64
+	}
+	var actual []segInfo
+	for _, seg := range parsed.Segments {
+		var sz uint64
+		if seg.Styp != nil {
+			sz += seg.Styp.Size()
+		}
+		if seg.Sidx != nil {
+			sz += seg.Sidx.Size()
+		}
+		var dur uint64
+		for _, fr := range seg.Fragments {
+			sz += fr.Moof.Size()
+			if fr.Mdat != nil {
+				sz += fr.Mdat.Size()
+			}
+			for _, traf := range fr.Moof.Trafs {
+				if traf.Tfhd.TrackID != 1 {
+					continue
+				}
+				for _, trun := range traf.Truns {
+					for _, s := range trun.Samples {
+						dur += uint64(s.Dur)
+					}
+				}
+			}
+		}
+		actual = append(actual, segInfo{size: sz, dur: dur})
+	}
+	for i := range actual {
+		refStr := "(no sidx ref)"
+		if i < len(sidxRefs) {
+			r := sidxRefs[i]
+			mark := ""
+			if uint64(r.ReferencedSize) != actual[i].size {
+				mark += fmt.Sprintf(" SIZE MISMATCH actual=%d", actual[i].size)
+			}
+			if uint64(r.SubSegmentDuration) != actual[i].dur {
+				mark += fmt.Sprintf(" DUR MISMATCH actual=%d", actual[i].dur)
+			}
+			refStr = fmt.Sprintf("sidx.size=%d sidx.dur=%d type=%d sap=%d/%d%s",
+				r.ReferencedSize, r.SubSegmentDuration, r.ReferenceType, r.StartsWithSAP, r.SAPType, mark)
+		}
+		fmt.Printf("  seg%02d actual.size=%d actual.dur=%d | %s\n", i, actual[i].size, actual[i].dur, refStr)
+	}
+
+	fmt.Println("=== fragments ===")
+	fragIdx := 0
+	var allKeyGlobal []uint64 // global keyframe decode times (track timescale units)
+	var prevTfdtEnd = map[uint32]uint64{}
+	for si, seg := range parsed.Segments {
+		for _, fr := range seg.Fragments {
+			for _, traf := range fr.Moof.Trafs {
+				tid := traf.Tfhd.TrackID
+				tfdt := traf.Tfdt.BaseMediaDecodeTime()
+				offset := uint64(0)
+				var keys []uint64 // keyframe offset-from-tfdt
+				var durs []uint64
+				zeroDur := 0
+				nSamples := 0
+				for _, trun := range traf.Truns {
+					for _, s := range trun.Samples {
+						nSamples++
+						if (s.Flags>>24)&0x03 == 0x02 { // sample_depends_on==2 => IDR/sync
+							keys = append(keys, offset)
+							if tid == 1 {
+								allKeyGlobal = append(allKeyGlobal, tfdt+offset)
+							}
+						}
+						if s.Dur == 0 {
+							zeroDur++
+						}
+						durs = append(durs, uint64(s.Dur))
+						offset += uint64(s.Dur)
+					}
+				}
+				cont := ""
+				if pe, ok := prevTfdtEnd[tid]; ok {
+					if tfdt != pe {
+						cont = fmt.Sprintf(" <-- tfdt GAP/JUMP prev_end=%d delta=%d", pe, int64(tfdt)-int64(pe))
+					}
+				}
+				prevTfdtEnd[tid] = tfdt + offset
+				if tid == 1 {
+					// in-fragment keyframe gaps
+					var gaps []int64
+					for i := 1; i < len(keys); i++ {
+						gaps = append(gaps, int64(keys[i])-int64(keys[i-1]))
+					}
+					fmt.Printf("seg%d frag%d trk%d tfdt=%d dur=%d nSamp=%d zeroDur=%d keys=%v inFragKeyGaps=%v%s\n",
+						si, fragIdx, tid, tfdt, offset, nSamples, zeroDur, keys, gaps, cont)
+				}
+			}
+			fragIdx++
+		}
+	}
+
+	fmt.Println("=== global video keyframe decode times & gaps ===")
+	for i, k := range allKeyGlobal {
+		gap := int64(0)
+		if i > 0 {
+			gap = int64(k) - int64(allKeyGlobal[i-1])
+		}
+		seam := ""
+		if i > 1 {
+			prevGap := int64(allKeyGlobal[i-1]) - int64(allKeyGlobal[i-2])
+			if gap > 0 && prevGap > 0 && gap*2 < prevGap {
+				seam = fmt.Sprintf("  <== SEAM? gap=%d < prevGap/2=%d", gap, prevGap/2)
+			}
+		}
+		fmt.Printf("  kf#%02d dt=%d gap=%d%s\n", i, k, gap, seam)
+	}
+
+	// Choose the detailed-inspection window. By default centre it on the largest
+	// keyframe gap (the most likely artifact location); -from/-to override.
+	winLo, winHi := inspectWindow(allKeyGlobal, *fromFlag, *toFlag)
+	fmt.Printf("=== detailed inspection window: dts %d..%d ===\n", winLo, winHi)
+
+	// Full sample timeline: DTS, CTS (=DTS+cto), composition offset, NAL types,
+	// to detect PTS non-monotonicity / gaps / param-set changes at the seam.
+	fmt.Println("=== per-sample timeline (full) — checking PTS monotonicity & nal types ===")
+	var trex *mp4ff.TrexBox
+	if parsed.Init != nil && parsed.Init.Moov != nil && parsed.Init.Moov.Mvex != nil {
+		for _, t := range parsed.Init.Moov.Mvex.Trexs {
+			if t.TrackID == 1 {
+				trex = t
+			}
+		}
+	}
+	var lastCTS int64 = -1
+	var lastDTS int64 = -1
+	sampIdx := 0
+	fragIdx = 0
+	for _, seg := range parsed.Segments {
+		for _, fr := range seg.Fragments {
+			fs, err := fr.GetFullSamples(trex)
+			if err != nil {
+				fmt.Printf("  frag%d GetFullSamples err: %v\n", fragIdx, err)
+				fragIdx++
+				continue
+			}
+			for _, s := range fs {
+				dts := int64(s.DecodeTime)
+				cts := dts + int64(s.CompositionTimeOffset)
+				nals := nalTypes(s.Data)
+				anomaly := ""
+				if lastCTS >= 0 && cts < lastCTS {
+					anomaly += fmt.Sprintf(" <== CTS BACKWARDS (prev=%d)", lastCTS)
+				}
+				if lastDTS >= 0 && dts < lastDTS {
+					anomaly += fmt.Sprintf(" <== DTS BACKWARDS (prev=%d)", lastDTS)
+				}
+				// sample_is_non_sync_sample is bit 16 (0x00010000); a sync sample
+				// has it clear and sample_depends_on==2 (i.e. an I-frame).
+				isSync := s.Flags&0x00010000 == 0 && (s.Flags>>24)&0x03 == 0x02
+				// Only print inside the inspection window and any anomalies, to keep output small.
+				near := dts >= winLo && dts <= winHi
+				if near || anomaly != "" {
+					fmt.Printf("  s%04d frag%d dts=%d cts=%d cto=%d dur=%d size=%d sync=%v nal=%v%s\n",
+						sampIdx, fragIdx, dts, cts, s.CompositionTimeOffset, s.Dur, len(s.Data), isSync, nals, anomaly)
+				}
+				lastCTS = cts
+				lastDTS = dts
+				sampIdx++
+			}
+			fragIdx++
+		}
+	}
+
+	// Compare parameter sets: avcC (in moov) vs inline SPS/PPS at every IDR.
+	// A looping source that restarts may re-emit SPS/PPS that differ from the
+	// ones the player configured its decoder with from avcC — a classic cause
+	// of a freeze that "heals" when you seek past the seam.
+	fmt.Println("=== parameter set comparison (avcC vs inline IDR) ===")
+	var avccSPS, avccPPS [][]byte
+	if parsed.Init != nil && parsed.Init.Moov != nil {
+		for _, trak := range parsed.Init.Moov.Traks {
+			if trak.Mdia == nil || trak.Mdia.Minf == nil || trak.Mdia.Minf.Stbl == nil {
+				continue
+			}
+			stsd := trak.Mdia.Minf.Stbl.Stsd
+			if stsd == nil || stsd.AvcX == nil || stsd.AvcX.AvcC == nil {
+				continue
+			}
+			avccSPS = stsd.AvcX.AvcC.SPSnalus
+			avccPPS = stsd.AvcX.AvcC.PPSnalus
+		}
+	}
+	for i, s := range avccSPS {
+		fmt.Printf("  avcC SPS[%d] = %x\n", i, s)
+	}
+	for i, p := range avccPPS {
+		fmt.Printf("  avcC PPS[%d] = %x\n", i, p)
+	}
+	fragIdx = 0
+	sampIdx = 0
+	var baseSPS, basePPS []byte
+	if len(avccSPS) > 0 {
+		baseSPS = avccSPS[0]
+	}
+	if len(avccPPS) > 0 {
+		basePPS = avccPPS[0]
+	}
+	for _, seg := range parsed.Segments {
+		for _, fr := range seg.Fragments {
+			fs, err := fr.GetFullSamples(trex)
+			if err != nil {
+				fragIdx++
+				continue
+			}
+			for _, s := range fs {
+				spsList := nalsByType(s.Data, 7)
+				ppsList := nalsByType(s.Data, 8)
+				if len(spsList) > 0 || len(ppsList) > 0 {
+					dts := int64(s.DecodeTime)
+					note := ""
+					if len(spsList) > 0 {
+						if baseSPS == nil {
+							baseSPS = spsList[0]
+						} else if !bytesEqual(baseSPS, spsList[0]) {
+							note += " <== SPS CHANGED vs base/avcC"
+						}
+					}
+					if len(ppsList) > 0 {
+						if basePPS == nil {
+							basePPS = ppsList[0]
+						} else if !bytesEqual(basePPS, ppsList[0]) {
+							note += " <== PPS CHANGED vs base/avcC"
+						}
+					}
+					var spsHex, ppsHex string
+					if len(spsList) > 0 {
+						spsHex = fmt.Sprintf("%x", spsList[0])
+					}
+					if len(ppsList) > 0 {
+						ppsHex = fmt.Sprintf("%x", ppsList[0])
+					}
+					fmt.Printf("  IDR s%04d frag%d dts=%d SPS=%s PPS=%s%s\n",
+						sampIdx, fragIdx, dts, spsHex, ppsHex, note)
+				}
+				sampIdx++
+			}
+			fragIdx++
+		}
+	}
+
+	sliceHeaders(parsed, trex, winLo, winHi)
+
+	summary(parsed, trex)
+}
+
+func sliceHeaders(parsed *mp4ff.File, trex *mp4ff.TrexBox, winLo, winHi int64) {
+	// Build SPS/PPS maps from avcC.
+	spsMap := map[uint32]*avc.SPS{}
+	ppsMap := map[uint32]*avc.PPS{}
+	if parsed.Init != nil && parsed.Init.Moov != nil {
+		for _, trak := range parsed.Init.Moov.Traks {
+			if trak.Mdia == nil || trak.Mdia.Minf == nil || trak.Mdia.Minf.Stbl == nil {
+				continue
+			}
+			stsd := trak.Mdia.Minf.Stbl.Stsd
+			if stsd == nil || stsd.AvcX == nil || stsd.AvcX.AvcC == nil {
+				continue
+			}
+			for _, s := range stsd.AvcX.AvcC.SPSnalus {
+				if sps, err := avc.ParseSPSNALUnit(s, true); err == nil {
+					spsMap[uint32(sps.ParameterID)] = sps
+				}
+			}
+			for _, p := range stsd.AvcX.AvcC.PPSnalus {
+				if pps, err := avc.ParsePPSNALUnit(p, spsMap); err == nil {
+					ppsMap[pps.PicParameterSetID] = pps
+				}
+			}
+		}
+	}
+
+	fmt.Println("=== slice headers in inspection window (frame_num / poc / idr_pic_id) ===")
+	fragIdx := 0
+	sampIdx := 0
+	for _, seg := range parsed.Segments {
+		for _, fr := range seg.Fragments {
+			fs, err := fr.GetFullSamples(trex)
+			if err != nil {
+				fragIdx++
+				continue
+			}
+			for _, s := range fs {
+				dts := int64(s.DecodeTime)
+				if dts < winLo || dts > winHi {
+					sampIdx++
+					continue
+				}
+				for _, nal := range splitAVCC(s.Data) {
+					t := nal[0] & 0x1f
+					if t == 1 || t == 5 { // non-IDR or IDR slice
+						sh, err := avc.ParseSliceHeader(nal, spsMap, ppsMap)
+						if err != nil {
+							fmt.Printf("  s%04d frag%d dts=%d nalType=%d sliceHeader ERR: %v\n", sampIdx, fragIdx, dts, t, err)
+							break
+						}
+						fmt.Printf("  s%04d frag%d dts=%d nalType=%d sliceType=%v frameNum=%d idrPicId=%d pocLsb=%d\n",
+							sampIdx, fragIdx, dts, t, sh.SliceType, sh.FrameNum, sh.IDRPicID, sh.PicOrderCntLsb)
+						break
+					}
+				}
+				sampIdx++
+			}
+			fragIdx++
+		}
+	}
+}
+
+// splitAVCC splits a length-prefixed (4-byte) AVCC buffer into NAL units.
+func splitAVCC(b []byte) [][]byte {
+	var out [][]byte
+	i := 0
+	for i+4 <= len(b) {
+		n := int(uint32(b[i])<<24 | uint32(b[i+1])<<16 | uint32(b[i+2])<<8 | uint32(b[i+3]))
+		i += 4
+		if n <= 0 || i+n > len(b) {
+			break
+		}
+		out = append(out, b[i:i+n])
+		i += n
+	}
+	return out
+}
+
+func bytesEqual(a, b []byte) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for i := range a {
+		if a[i] != b[i] {
+			return false
+		}
+	}
+	return true
+}
+
+// nalTypes returns the list of H.264 NAL unit types present in an AVCC
+// (length-prefixed) sample buffer.
+func nalTypes(b []byte) []int {
+	var out []int
+	i := 0
+	for i+4 <= len(b) {
+		n := int(uint32(b[i])<<24 | uint32(b[i+1])<<16 | uint32(b[i+2])<<8 | uint32(b[i+3]))
+		i += 4
+		if n <= 0 || i+n > len(b) {
+			break
+		}
+		out = append(out, int(b[i]&0x1f))
+		i += n
+	}
+	return out
+}
+
+// nalsByType returns the raw NAL payloads (without length prefix) of the given
+// type from an AVCC (length-prefixed) sample buffer.
+func nalsByType(b []byte, want int) [][]byte {
+	var out [][]byte
+	i := 0
+	for i+4 <= len(b) {
+		n := int(uint32(b[i])<<24 | uint32(b[i+1])<<16 | uint32(b[i+2])<<8 | uint32(b[i+3]))
+		i += 4
+		if n <= 0 || i+n > len(b) {
+			break
+		}
+		if int(b[i]&0x1f) == want {
+			nal := make([]byte, n)
+			copy(nal, b[i:i+n])
+			out = append(out, nal)
+		}
+		i += n
+	}
+	return out
+}
+
+// inspectWindow returns the [lo,hi] decode-time range (track timescale units)
+// for which sample-level detail is printed. Explicit -from/-to win; otherwise
+// the window auto-centres on the largest gap between consecutive video
+// keyframes — the most likely location of a visible artifact — with a margin on
+// each side so the frames leading into and out of the gap are shown too.
+func inspectWindow(keyDecodeTimes []uint64, from, to int64) (int64, int64) {
+	if from >= 0 || to >= 0 {
+		if from < 0 {
+			from = 0
+		}
+		if to < 0 {
+			to = from + 2000
+		}
+		return from, to
+	}
+	if len(keyDecodeTimes) < 2 {
+		return 0, 1 << 62
+	}
+	worstIdx, worstGap := 1, uint64(0)
+	for i := 1; i < len(keyDecodeTimes); i++ {
+		if g := keyDecodeTimes[i] - keyDecodeTimes[i-1]; g > worstGap {
+			worstGap = g
+			worstIdx = i
+		}
+	}
+	const margin = 500
+	lo := int64(keyDecodeTimes[worstIdx-1]) - margin
+	if lo < 0 {
+		lo = 0
+	}
+	return lo, int64(keyDecodeTimes[worstIdx]) + margin
+}
+
+// summary prints a compact, generic health report so a recording can be
+// validated at a glance without reading the full per-sample dump above.
+func summary(parsed *mp4ff.File, trex *mp4ff.TrexBox) {
+	fmt.Println("=== SUMMARY (health checks) ===")
+
+	videoTracks, audioTracks := 0, 0
+	var videoTimescale uint64 = 1
+	if parsed.Init != nil && parsed.Init.Moov != nil {
+		for _, trak := range parsed.Init.Moov.Traks {
+			switch trak.Mdia.Hdlr.HandlerType {
+			case "vide":
+				videoTracks++
+				if trak.Mdia.Mdhd.Timescale != 0 {
+					videoTimescale = uint64(trak.Mdia.Mdhd.Timescale)
+				}
+			case "soun":
+				audioTracks++
+			}
+		}
+	}
+	fmt.Printf("  tracks: %d video, %d audio\n", videoTracks, audioTracks)
+	if audioTracks == 0 {
+		fmt.Println("    note: no audio track is embedded in this file")
+	}
+
+	type fragStat struct {
+		idx     int
+		tfdt    uint64
+		dur     uint64
+		nSamp   int
+		nKeys   int
+		zeroDur int
+		fps     float64
+	}
+	var stats []fragStat
+	var keyTimes []uint64
+	var fpsArr []float64
+	tfdtGaps := 0
+	var prevEnd uint64
+	havePrev := false
+	fi := 0
+	for _, seg := range parsed.Segments {
+		for _, fr := range seg.Fragments {
+			for _, traf := range fr.Moof.Trafs {
+				if traf.Tfhd.TrackID != 1 {
+					continue
+				}
+				st := fragStat{idx: fi, tfdt: traf.Tfdt.BaseMediaDecodeTime()}
+				off := uint64(0)
+				for _, trun := range traf.Truns {
+					for _, s := range trun.Samples {
+						st.nSamp++
+						if (s.Flags>>24)&0x03 == 0x02 {
+							st.nKeys++
+							keyTimes = append(keyTimes, st.tfdt+off)
+						}
+						if s.Dur == 0 {
+							st.zeroDur++
+						}
+						off += uint64(s.Dur)
+					}
+				}
+				st.dur = off
+				d := st.dur
+				if d == 0 {
+					d = 1
+				}
+				st.fps = float64(st.nSamp) * float64(videoTimescale) / float64(d)
+				fpsArr = append(fpsArr, st.fps)
+				if havePrev && st.tfdt != prevEnd {
+					tfdtGaps++
+				}
+				prevEnd = st.tfdt + st.dur
+				havePrev = true
+				stats = append(stats, st)
+			}
+			fi++
+		}
+	}
+
+	medFps := medianFloat(fpsArr)
+	fmt.Printf("  fragments: %d (video timescale=%d, median %.1f fps)\n", len(stats), videoTimescale, medFps)
+	lowFps := 0
+	totalZero := 0
+	for _, st := range stats {
+		totalZero += st.zeroDur
+		flagStr := ""
+		if medFps > 0 && st.fps < medFps*0.9 {
+			lowFps++
+			flagStr = "  <== LOW FRAME RATE — likely dropped frames"
+		}
+		fmt.Printf("    frag%02d tfdt=%-6d dur=%-5d samples=%-3d keyframes=%d zeroDur=%d fps=%.1f%s\n",
+			st.idx, st.tfdt, st.dur, st.nSamp, st.nKeys, st.zeroDur, st.fps, flagStr)
+	}
+
+	var gaps []uint64
+	for i := 1; i < len(keyTimes); i++ {
+		gaps = append(gaps, keyTimes[i]-keyTimes[i-1])
+	}
+	irregular := 0
+	if len(gaps) > 0 {
+		med := medianUint(gaps)
+		mn, mx := gaps[0], gaps[0]
+		for _, g := range gaps {
+			if g < mn {
+				mn = g
+			}
+			if g > mx {
+				mx = g
+			}
+			// Flag intervals that deviate by more than ~50% from the median GOP.
+			if med > 0 && (g*2 > med*3 || g*2 < med) {
+				irregular++
+			}
+		}
+		fmt.Printf("  keyframe gaps: min=%d median=%d max=%d  irregular=%d/%d\n", mn, med, mx, irregular, len(gaps))
+	}
+	fmt.Printf("  tfdt discontinuities: %d\n", tfdtGaps)
+	fmt.Printf("  zero-duration samples: %d\n", totalZero)
+
+	fmt.Println("  verdict:")
+	clean := true
+	if audioTracks == 0 {
+		fmt.Println("    - no audio track (expected if this recording is video-only)")
+	}
+	if lowFps > 0 {
+		clean = false
+		fmt.Printf("    - %d fragment(s) have a reduced frame rate (dropped frames) — likely source of the artifacts\n", lowFps)
+	}
+	if irregular > 0 {
+		clean = false
+		fmt.Printf("    - %d irregular keyframe interval(s)\n", irregular)
+	}
+	if tfdtGaps > 0 {
+		clean = false
+		fmt.Printf("    - %d timeline (tfdt) discontinuity(ies)\n", tfdtGaps)
+	}
+	if totalZero > 0 {
+		clean = false
+		fmt.Printf("    - %d zero-duration sample(s)\n", totalZero)
+	}
+	if clean {
+		fmt.Println("    - container structure looks healthy")
+	}
+}
+
+func medianUint(v []uint64) uint64 {
+	if len(v) == 0 {
+		return 0
+	}
+	c := append([]uint64(nil), v...)
+	sort.Slice(c, func(i, j int) bool { return c[i] < c[j] })
+	return c[len(c)/2]
+}
+
+func medianFloat(v []float64) float64 {
+	if len(v) == 0 {
+		return 0
+	}
+	c := append([]float64(nil), v...)
+	sort.Float64s(c)
+	return c[len(c)/2]
+}

machinery/data/config/config.json

@@ -106,9 +106,9 @@
 	"mqtturi": "tcp://mqtt.kerberos.io:1883",
 	"mqtt_username": "",
 	"mqtt_password": "",
-	"stunuri": "stun:turn.kerberos.io:8443",
 	"turn_force": "false",
-	"turnuri": "turn:turn.kerberos.io:8443",
+	"stunuri": "stun:turn-fra1.kerberos.io:3478",
+	"turnuri": "turn:turn-fra1.kerberos.io:3478",
 	"turn_username": "username1",
 	"turn_password": "password1",
 	"heartbeaturi": "",

machinery/src/capture/gortsplib.go

@@ -95,6 +95,129 @@ type Golibrtsp struct {
 	keyframeBufferSize       int
 	keyframeBufferIndex      int
 	keyframeMutex            sync.Mutex
+
+	// Stream health instrumentation. Used to pinpoint the root cause behind
+	// "RTP packets lost" + watchdog restarts by separating downstream
+	// back-pressure from upstream network/camera stalls.
+	health      *streamHealth
+	streamLabel string
+}
+
+// streamHealth instruments the RTSP read path. gortsplib delivers every RTP
+// packet on a single read goroutine; queue.WritePacket() is synchronous, so if
+// a downstream consumer (recording, muxing, WebRTC) is slow or the process is
+// CPU-starved, WritePacket() blocks, the TCP socket is not drained, and the
+// camera advances RTP sequence numbers -> "RTP packets lost". This type makes
+// the two failure modes distinguishable:
+//   - large writeMax / writeAvg  => downstream back-pressure (our side).
+//   - large gapMax with fast writes => upstream network / camera stall.
+type streamHealth struct {
+	mu          sync.Mutex
+	windowStart time.Time
+	lastPacket  time.Time
+	frames      int64
+	writeSum    time.Duration
+	writeMax    time.Duration
+	gapMax      time.Duration
+	lost        uint64
+	decodeErrs  int64
+}
+
+const (
+	streamHealthWindow    = 10 * time.Second
+	streamHealthWriteWarn = 150 * time.Millisecond
+	streamHealthGapWarn   = 1500 * time.Millisecond
+)
+
+func newStreamHealth() *streamHealth {
+	now := time.Now()
+	return &streamHealth{windowStart: now, lastPacket: now}
+}
+
+// observePacket records one processed video frame: the wall-clock gap since the
+// previous frame (arrival cadence) and how long WritePacket() blocked
+// (back-pressure). It emits an immediate warning when either side stalls and a
+// periodic summary every streamHealthWindow.
+func (h *streamHealth) observePacket(streamType string, writeDur time.Duration) {
+	if h == nil {
+		return
+	}
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	now := time.Now()
+	var gap time.Duration
+	if h.frames == 0 {
+		// First frame: initialize timing to avoid counting RTSP setup time as a stall.
+		h.windowStart = now
+		h.lastPacket = now
+		gap = 0
+	} else {
+		gap = now.Sub(h.lastPacket)
+		h.lastPacket = now
+	}
+	h.frames++
+	h.writeSum += writeDur
+	if writeDur > h.writeMax {
+		h.writeMax = writeDur
+	}
+	if gap > h.gapMax {
+		h.gapMax = gap
+	}
+	if writeDur >= streamHealthWriteWarn {
+		log.Log.Warning(fmt.Sprintf(
+			"capture.golibrtsp.health(%s): WritePacket blocked %dms — downstream back-pressure / CPU starvation",
+			streamType, writeDur.Milliseconds()))
+	}
+	if gap >= streamHealthGapWarn {
+		log.Log.Warning(fmt.Sprintf(
+			"capture.golibrtsp.health(%s): %dms since previous frame — upstream network / camera stall",
+			streamType, gap.Milliseconds()))
+	}
+	if now.Sub(h.windowStart) >= streamHealthWindow {
+		elapsed := now.Sub(h.windowStart).Seconds()
+		var avgWriteMs float64
+		if h.frames > 0 {
+			avgWriteMs = float64(h.writeSum.Milliseconds()) / float64(h.frames)
+		}
+		log.Log.Info(fmt.Sprintf(
+			"capture.golibrtsp.health(%s): %.0fs window — frames=%d (%.1f/s) writeAvg=%.1fms writeMax=%dms gapMax=%dms lost=%d decodeErrs=%d",
+			streamType, elapsed, h.frames, float64(h.frames)/elapsed, avgWriteMs,
+			h.writeMax.Milliseconds(), h.gapMax.Milliseconds(), h.lost, h.decodeErrs))
+		h.windowStart = now
+		h.frames = 0
+		h.writeSum = 0
+		h.writeMax = 0
+		h.gapMax = 0
+		h.lost = 0
+		h.decodeErrs = 0
+	}
+}
+
+// observeLost is invoked by gortsplib when RTP sequence numbers skip. On a TCP
+// transport this means the sender (camera) dropped packets because we were not
+// reading fast enough, not loss on the wire.
+func (h *streamHealth) observeLost(streamType string, lost uint64) {
+	if h == nil {
+		return
+	}
+	h.mu.Lock()
+	h.lost += lost
+	h.mu.Unlock()
+	log.Log.Warning(fmt.Sprintf(
+		"capture.golibrtsp.health(%s): %d RTP packet(s) lost — sender-side gap (receiver not draining TCP fast enough)",
+		streamType, lost))
+}
+
+// observeDecodeError is invoked by gortsplib on incomplete/invalid access units,
+// which are a downstream symptom of the loss reported by observeLost.
+func (h *streamHealth) observeDecodeError(streamType string, err error) {
+	if h == nil {
+		return
+	}
+	h.mu.Lock()
+	h.decodeErrs++
+	h.mu.Unlock()
+	log.Log.Debug(fmt.Sprintf("capture.golibrtsp.health(%s): decode error: %s", streamType, err.Error()))
 }
 
 // fpsTracker holds per-stream state for PTS-based FPS calculation.
@@ -195,9 +318,20 @@ func (g *Golibrtsp) Connect(ctx context.Context, ctxOtel context.Context) (err e
 	defer span.End()
 
 	transport := gortsplib.TransportTCP
+	g.health = newStreamHealth()
 	g.Client = gortsplib.Client{
 		RequestBackChannels: false,
 		Transport:           &transport,
+		// Route gortsplib's packet-loss / decode-error reporting through our
+		// structured logger with stream context (replaces its plain stdout
+		// logging). These hooks are what let us tell whether the camera is
+		// dropping packets because we can't drain the socket fast enough.
+		OnPacketsLost: func(lost uint64) {
+			g.health.observeLost(g.streamLabel, lost)
+		},
+		OnDecodeError: func(err error) {
+			g.health.observeDecodeError(g.streamLabel, err)
+		},
 	}
 
 	// parse URL
@@ -517,10 +651,45 @@ func (g *Golibrtsp) ConnectBackChannel(ctx context.Context, ctxRunAgent context.
 	return
 }
 
+// dtsExtractor abstracts the codec-specific DTS extractors from mediacommon
+// (h264.DTSExtractor2 and h265.DTSExtractor2), which expose the same method.
+type dtsExtractor interface {
+	Extract(au [][]byte, pts int64) (int64, error)
+}
+
+// compositionOffsetMs returns the composition time offset (PTS - DTS) in
+// milliseconds for a coded access unit. Streams that contain B-frames deliver
+// access units in decode order with non-monotonic PTS; the fragmented MP4
+// writer needs a monotonic DTS timeline plus a per-sample composition offset
+// so browsers (Media Source Extensions) can decode the chained segments.
+//
+// It returns 0 when the codec has no frame reordering (the common case, e.g.
+// baseline "IPPP" streams) or when extraction fails, making it a safe no-op.
+func compositionOffsetMs(ext dtsExtractor, au [][]byte, pts int64, clockRate int) int64 {
+	if ext == nil || clockRate <= 0 {
+		return 0
+	}
+	dts, err := ext.Extract(au, pts)
+	if err != nil {
+		return 0
+	}
+	offset := pts - dts
+	if offset <= 0 {
+		return 0
+	}
+	return offset * 1000 / int64(clockRate)
+}
+
 // Start the RTSP client, and start reading packets.
 func (g *Golibrtsp) Start(ctx context.Context, streamType string, queue *packets.Queue, configuration *models.Configuration, communication *models.Communication) (err error) {
 	log.Log.Debug("capture.golibrtsp.Start(): started")
 
+	// Label this client's loss/decode/health logging with the stream type.
+	g.streamLabel = streamType
+	if g.health == nil {
+		g.health = newStreamHealth()
+	}
+
 	// called when a MULAW audio RTP packet arrives
 	if g.AudioG711Media != nil && g.AudioG711Forma != nil {
 		g.Client.OnPacketRTP(g.AudioG711Media, g.AudioG711Forma, func(rtppkt *rtp.Packet) {
@@ -602,7 +771,9 @@ func (g *Golibrtsp) Start(ctx context.Context, streamType string, queue *packets
 	var filteredAU [][]byte
 	if g.VideoH264Media != nil && g.VideoH264Forma != nil {
 
-		//dtsExtractor := h264.NewDTSExtractor2()
+		// Extracts DTS from the bitstream to support B-frame H264 streams.
+		// Created once per stream (tracks reorder state across access units).
+		h264DTSExtractor := h264.NewDTSExtractor2()
 
 		g.Client.OnPacketRTP(g.VideoH264Media, g.VideoH264Forma, func(rtppkt *rtp.Packet) {
 
@@ -742,6 +913,11 @@ func (g *Golibrtsp) Start(ctx context.Context, streamType string, queue *packets
 					return
 				}
 
+				// Composition time offset (PTS - DTS) in milliseconds. Non-zero
+				// only for streams with B-frames; the MP4 writer uses it to keep a
+				// monotonic decode timeline and present frames in PTS order.
+				compositionOffset := compositionOffsetMs(h264DTSExtractor, au, pts2, g.VideoH264Forma.ClockRate())
+
 				pkt := packets.Packet{
 					IsKeyFrame:      idrPresent,
 					Packet:          rtppkt,
@@ -749,7 +925,7 @@ func (g *Golibrtsp) Start(ctx context.Context, streamType string, queue *packets
 					Time:            pts2,
 					TimeLegacy:      pts,
 					CurrentTime:     time.Now().UnixMilli(),
-					CompositionTime: pts2,
+					CompositionTime: compositionOffset,
 					Idx:             g.VideoH264Index,
 					IsVideo:         true,
 					IsAudio:         false,
@@ -777,15 +953,38 @@ func (g *Golibrtsp) Start(ctx context.Context, streamType string, queue *packets
 
 				pkt.Data = pkt.Data[4:]
 				if pkt.IsKeyFrame {
-					annexbNALUStartCode := func() []byte { return []byte{0x00, 0x00, 0x00, 0x01} }
-					pkt.Data = append(annexbNALUStartCode(), pkt.Data...)
-					pkt.Data = append(g.VideoH264Forma.PPS, pkt.Data...)
-					pkt.Data = append(annexbNALUStartCode(), pkt.Data...)
-					pkt.Data = append(g.VideoH264Forma.SPS, pkt.Data...)
-					pkt.Data = append(annexbNALUStartCode(), pkt.Data...)
+					// Prepend SPS/PPS (when available) in front of every keyframe so the
+					// access unit is self-contained. Downstream decoders (and the MP4 writer's
+					// in-band parameter-set recovery) rely on this; a recording whose first
+					// frame lacks SPS/PPS produces an MP4 with an empty avcC, which makes FFmpeg
+					// report "non-existing PPS 0 referenced".
+					//
+					// Build the payload in a freshly allocated buffer. The previous code
+					// did append(g.VideoH264Forma.PPS, pkt.Data...): because the SPS/PPS
+					// slices are sub-slices of the RTP reassembly buffer (spare capacity),
+					// that append wrote into - and corrupted - the shared parameter-set
+					// backing arrays, occasionally poisoning the SPS/PPS stored for the
+					// recording.
+					startCode := []byte{0x00, 0x00, 0x00, 0x01}
+					out := make([]byte, 0, len(g.VideoH264Forma.SPS)+len(g.VideoH264Forma.PPS)+len(pkt.Data)+12)
+					if len(g.VideoH264Forma.SPS) > 0 {
+						out = append(out, startCode...)
+						out = append(out, g.VideoH264Forma.SPS...)
+					}
+					if len(g.VideoH264Forma.PPS) > 0 {
+						out = append(out, startCode...)
+						out = append(out, g.VideoH264Forma.PPS...)
+					}
+					out = append(out, startCode...)
+					out = append(out, pkt.Data...)
+					pkt.Data = out
 				}
 
+				writeStart := time.Now()
 				queue.WritePacket(pkt)
+				// Records WritePacket() blocking time and frame arrival cadence so
+				// we can tell back-pressure from a network/camera stall.
+				g.health.observePacket(streamType, time.Since(writeStart))
 
 				// This will check if we need to stop the thread,
 				// because of a reconfiguration.
@@ -817,6 +1016,11 @@ func (g *Golibrtsp) Start(ctx context.Context, streamType string, queue *packets
 
 	// called when a video RTP packet arrives for H265
 	if g.VideoH265Media != nil && g.VideoH265Forma != nil {
+
+		// Extracts DTS from the bitstream to support B-frame H265 streams.
+		// Created once per stream (tracks reorder state across access units).
+		h265DTSExtractor := h265.NewDTSExtractor2()
+
 		g.Client.OnPacketRTP(g.VideoH265Media, g.VideoH265Forma, func(rtppkt *rtp.Packet) {
 
 			// This will check if we need to stop the thread,
@@ -860,6 +1064,10 @@ func (g *Golibrtsp) Start(ctx context.Context, streamType string, queue *packets
 					}
 				}
 
+				// Preserve the decoded access unit (in decode order) for DTS
+				// extraction before we rewrite it into the filtered/annexb form.
+				decodedAU := au
+
 				filteredAU = [][]byte{
 					{byte(h265.NALUType_AUD_NUT) << 1, 1, 0x50},
 				}
@@ -902,6 +1110,9 @@ func (g *Golibrtsp) Start(ctx context.Context, streamType string, queue *packets
 					return
 				}
 
+				// Composition time offset (PTS - DTS) in milliseconds; see H264 handler.
+				compositionOffset := compositionOffsetMs(h265DTSExtractor, decodedAU, pts2, g.VideoH265Forma.ClockRate())
+
 				pkt := packets.Packet{
 					IsKeyFrame:      isRandomAccess,
 					Packet:          rtppkt,
@@ -909,7 +1120,7 @@ func (g *Golibrtsp) Start(ctx context.Context, streamType string, queue *packets
 					Time:            pts2,
 					TimeLegacy:      pts,
 					CurrentTime:     time.Now().UnixMilli(),
-					CompositionTime: pts2,
+					CompositionTime: compositionOffset,
 					Idx:             g.VideoH265Index,
 					IsVideo:         true,
 					IsAudio:         false,
@@ -935,7 +1146,11 @@ func (g *Golibrtsp) Start(ctx context.Context, streamType string, queue *packets
 					}
 				}
 
+				writeStart := time.Now()
 				queue.WritePacket(pkt)
+				// Records WritePacket() blocking time and frame arrival cadence so
+				// we can tell back-pressure from a network/camera stall.
+				g.health.observePacket(streamType, time.Since(writeStart))
 
 				// This will check if we need to stop the thread,
 				// because of a reconfiguration.

machinery/src/capture/main.go

@@ -140,23 +140,8 @@ func HandleRecordStream(queue *packets.Queue, configDirectory string, configurat
 				if start && // If already recording and current frame is a keyframe and we should stop recording
 					nextPkt.IsKeyFrame && (startRecording+postRecording-now <= 0 || now-startRecording > maxRecordingPeriod-500) {
 
-					pts := convertPTS(pkt.TimeLegacy)
-					if pkt.IsVideo {
-						// Write the last packet
-						if err := mp4Video.AddSampleToTrack(videoTrack, pkt.IsKeyFrame, pkt.Data, pts); err != nil {
-							log.Log.Error("capture.main.HandleRecordStream(continuous): " + err.Error())
-						}
-					} else if pkt.IsAudio {
-						// Write the last packet
-						if pkt.Codec == "AAC" {
-							if err := mp4Video.AddSampleToTrack(audioTrack, pkt.IsKeyFrame, pkt.Data, pts); err != nil {
-								log.Log.Error("capture.main.HandleRecordStream(continuous): " + err.Error())
-							}
-						} else if pkt.Codec == "PCM_MULAW" {
-							// TODO: transcode to AAC, some work to do..
-							log.Log.Debug("capture.main.HandleRecordStream(continuous): no AAC audio codec detected, skipping audio track.")
-						}
-					}
+					// Write the last packet before closing the recording.
+					writeSampleToMP4(mp4Video, videoTrack, audioTrack, pkt)
 
 					// Close mp4
 					if len(mp4Video.SPSNALUs) == 0 && len(configuration.Config.Capture.IPCamera.SPSNALUs) > 0 {
@@ -311,43 +296,12 @@ func HandleRecordStream(queue *packets.Queue, configDirectory string, configurat
 						log.Log.Debug("capture.main.HandleRecordStream(continuous): no AAC audio codec detected, skipping audio track.")
 					}
 
-					pts := convertPTS(pkt.TimeLegacy)
-					if pkt.IsVideo {
-						if err := mp4Video.AddSampleToTrack(videoTrack, pkt.IsKeyFrame, pkt.Data, pts); err != nil {
-							log.Log.Error("capture.main.HandleRecordStream(continuous): " + err.Error())
-						}
-					} else if pkt.IsAudio {
-						if pkt.Codec == "AAC" {
-							if err := mp4Video.AddSampleToTrack(audioTrack, pkt.IsKeyFrame, pkt.Data, pts); err != nil {
-								log.Log.Error("capture.main.HandleRecordStream(continuous): " + err.Error())
-							}
-						} else if pkt.Codec == "PCM_MULAW" {
-							// TODO: transcode to AAC, some work to do..
-							// We might need to use ffmpeg to transcode the audio to AAC.
-							// For now we will skip the audio track.
-							log.Log.Debug("capture.main.HandleRecordStream(continuous): no AAC audio codec detected, skipping audio track.")
-						}
-					}
+					writeSampleToMP4(mp4Video, videoTrack, audioTrack, pkt)
 					recordingStatus = "started"
 
 				} else if start {
 
-					pts := convertPTS(pkt.TimeLegacy)
-					if pkt.IsVideo {
-						// New method using new mp4 library
-						if err := mp4Video.AddSampleToTrack(videoTrack, pkt.IsKeyFrame, pkt.Data, pts); err != nil {
-							log.Log.Error("capture.main.HandleRecordStream(continuous): " + err.Error())
-						}
-					} else if pkt.IsAudio {
-						if pkt.Codec == "AAC" {
-							if err := mp4Video.AddSampleToTrack(audioTrack, pkt.IsKeyFrame, pkt.Data, pts); err != nil {
-								log.Log.Error("capture.main.HandleRecordStream(continuous): " + err.Error())
-							}
-						} else if pkt.Codec == "PCM_MULAW" {
-							// TODO: transcode to AAC, some work to do..
-							log.Log.Debug("capture.main.HandleRecordStream(continuous): no AAC audio codec detected, skipping audio track.")
-						}
-					}
+					writeSampleToMP4(mp4Video, videoTrack, audioTrack, pkt)
 				}
 				pkt = nextPkt
 			}
@@ -571,29 +525,7 @@ func HandleRecordStream(queue *packets.Queue, configDirectory string, configurat
 						start = true
 					}
 					if start {
-						pts := convertPTS(pkt.TimeLegacy)
-						if pkt.IsVideo {
-							log.Log.Debug("capture.main.HandleRecordStream(motiondetection): add video sample")
-							if mp4Video != nil {
-								if err := mp4Video.AddSampleToTrack(videoTrack, pkt.IsKeyFrame, pkt.Data, pts); err != nil {
-									log.Log.Error("capture.main.HandleRecordStream(motiondetection): " + err.Error())
-								}
-							}
-						} else if pkt.IsAudio {
-							log.Log.Debug("capture.main.HandleRecordStream(motiondetection): add audio sample")
-							if pkt.Codec == "AAC" {
-								if mp4Video != nil {
-									if err := mp4Video.AddSampleToTrack(audioTrack, pkt.IsKeyFrame, pkt.Data, pts); err != nil {
-										log.Log.Error("capture.main.HandleRecordStream(motiondetection): " + err.Error())
-									}
-								}
-							} else if pkt.Codec == "PCM_MULAW" {
-								// TODO: transcode to AAC, some work to do..
-								// We might need to use ffmpeg to transcode the audio to AAC.
-								// For now we will skip the audio track.
-								log.Log.Debug("capture.main.HandleRecordStream(motiondetection): no AAC audio codec detected, skipping audio track.")
-							}
-						}
+						writeSampleToMP4(mp4Video, videoTrack, audioTrack, pkt)
 					}
 
 					pkt = nextPkt
@@ -867,6 +799,41 @@ func convertPTS(v time.Duration) uint64 {
 	return uint64(v.Milliseconds())
 }
 
+// writeSampleToMP4 writes a single capture packet to the fragmented MP4.
+//
+// For video it derives the decode timestamp (DTS) from the packet PTS using the
+// per-packet composition offset (PTS - DTS), which is non-zero only for streams
+// that contain B-frames. Passing the monotonic DTS as the sample timestamp keeps
+// the fragment timeline (tfdt/sidx) monotonic, while the composition offset is
+// forwarded so frames are still presented in PTS order.
+func writeSampleToMP4(mp4Video *video.MP4, videoTrack, audioTrack uint32, pkt packets.Packet) {
+	if mp4Video == nil {
+		return
+	}
+
+	pts := convertPTS(pkt.TimeLegacy)
+
+	if pkt.IsVideo {
+		compositionOffset := pkt.CompositionTime
+		dts := pts
+		if compositionOffset > 0 && uint64(compositionOffset) <= pts {
+			dts = pts - uint64(compositionOffset)
+		}
+		if err := mp4Video.AddSampleToTrack(videoTrack, pkt.IsKeyFrame, pkt.Data, dts, compositionOffset); err != nil {
+			log.Log.Error("capture.main.writeSampleToMP4(): " + err.Error())
+		}
+	} else if pkt.IsAudio {
+		if pkt.Codec == "AAC" {
+			if err := mp4Video.AddSampleToTrack(audioTrack, pkt.IsKeyFrame, pkt.Data, pts, 0); err != nil {
+				log.Log.Error("capture.main.writeSampleToMP4(): " + err.Error())
+			}
+		} else if pkt.Codec == "PCM_MULAW" {
+			// TODO: transcode to AAC, some work to do..
+			log.Log.Debug("capture.main.writeSampleToMP4(): no AAC audio codec detected, skipping audio track.")
+		}
+	}
+}
+
 /*func convertPTS2(v int64) uint64 {
 	return uint64(v) / 100
 }*/

machinery/src/cloud/cloud.go

@@ -2,6 +2,7 @@ package cloud
 
 import (
 	"bytes"
+	"context"
 	"crypto/tls"
 	"encoding/base64"
 	"encoding/json"
@@ -21,6 +22,7 @@ import (
 	"time"
 
 	"github.com/kerberos-io/agent/machinery/src/capture"
+	"github.com/kerberos-io/agent/machinery/src/cloud/livesnapshot"
 	"github.com/kerberos-io/agent/machinery/src/encryption"
 	"github.com/kerberos-io/agent/machinery/src/log"
 	"github.com/kerberos-io/agent/machinery/src/models"
@@ -528,6 +530,7 @@ loop:
 						"onvif_events_list": %s,
 						"cameraConnected": "%s",
 						"hasBackChannel": "%s",
+						"livePreviewHttp": true,
 						"numberoffiles" : "33",
 						"timestamp" : 1564747908,
 						"cameratype" : "IPCamera",
@@ -684,7 +687,35 @@ func HandleLiveStreamSD(livestreamCursor *packets.QueueCursor, configuration *mo
 				hubKey = config.HubKey
 			}
 
-			lastLivestreamRequest := int64(0)
+			lastLivestreamRequestMQTT := int64(0)
+			lastLivestreamRequestHTTP := int64(0)
+
+			// HTTP transport (preferred when this agent is paired with a Kerberos
+			// Hub): ship preview frames to hub-api over HTTPS instead of pushing
+			// (large, base64) images through the MQTT broker. Viewers opt in per
+			// session via the "http" transport on their keepalive; the legacy MQTT
+			// push is kept for viewers (older frontends) that don't, and as a fallback.
+			region := ""
+			if config.S3 != nil {
+				region = config.S3.Region
+			}
+			var snapshotPublisher *livesnapshot.Publisher
+			if config.HubURI != "" && config.HubKey != "" {
+				snapshotPublisher = livesnapshot.NewPublisher(livesnapshot.PublisherConfig{
+					HubURI:        config.HubURI,
+					HubKey:        config.HubKey,
+					HubPrivateKey: config.HubPrivateKey,
+					Region:        region,
+					DeviceKey:     deviceId,
+				})
+				log.Log.Info("cloud.HandleLiveStreamSD(): HTTP preview transport ENABLED; frames go to " + strings.TrimRight(config.HubURI, "/") + "/storage/snapshot when a viewer requests it (kept off MQTT).")
+			} else {
+				log.Log.Info("cloud.HandleLiveStreamSD(): HTTP preview transport DISABLED (Hub not configured: HubURI/HubKey empty); preview frames are pushed over MQTT.")
+			}
+
+			// Track the transport actually used so we log only when it changes; the
+			// loop runs once per keyframe and logging every frame would be noise.
+			lastTransport := ""
 
 			var cursorError error
 			var pkt packets.Packet
@@ -695,20 +726,74 @@ func HandleLiveStreamSD(livestreamCursor *packets.QueueCursor, configuration *mo
 					continue
 				}
 				now := time.Now().Unix()
+				// Drain both viewer keepalive channels (non-blocking): one for the
+				// HTTP transport, one for the legacy MQTT push.
 				select {
 				case <-communication.HandleLiveSD:
-					lastLivestreamRequest = now
+					lastLivestreamRequestMQTT = now
 				default:
 				}
-				if now-lastLivestreamRequest > 3 {
+				select {
+				case <-communication.HandleLiveSDHTTP:
+					lastLivestreamRequestHTTP = now
+				default:
+				}
+
+				mqttViewerActive := now-lastLivestreamRequestMQTT <= 3
+				httpViewerActive := now-lastLivestreamRequestHTTP <= 3
+				if !mqttViewerActive && !httpViewerActive {
 					continue
 				}
-				log.Log.Info("cloud.HandleLiveStreamSD(): Sending base64 encoded images to MQTT.")
-				img, err := rtspClient.DecodePacket(pkt)
-				if err == nil {
-					imageResized, _ := utils.ResizeImage(&img, uint(config.Capture.IPCamera.BaseWidth), uint(config.Capture.IPCamera.BaseHeight))
-					bytes, _ := utils.ImageToBytes(imageResized)
 
+				img, err := rtspClient.DecodePacket(pkt)
+				if err != nil {
+					continue
+				}
+				imageResized, _ := utils.ResizeImage(&img, uint(config.Capture.IPCamera.BaseWidth), uint(config.Capture.IPCamera.BaseHeight))
+				bytes, _ := utils.ImageToBytes(imageResized)
+
+				// Prefer HTTP for viewers that asked for it. Only if that did not
+				// deliver (Hub not configured, or the upload failed) do we also push
+				// over MQTT, so a new frontend can still fall back to its MQTT path.
+				httpPushed := false
+				var httpErr error
+				if httpViewerActive && snapshotPublisher != nil {
+					ctx, cancel := context.WithTimeout(context.Background(), 4*time.Second)
+					httpErr = snapshotPublisher.PublishSnapshot(ctx, bytes)
+					if httpErr == nil {
+						httpPushed = true
+					}
+					cancel()
+				}
+
+				pushMQTT := mqttViewerActive || (httpViewerActive && !httpPushed)
+
+				// Log only when the effective transport changes, so an operator can
+				// tell at a glance whether a device's preview travels over HTTP or
+				// MQTT (and why it fell back) without per-frame log spam.
+				transport := ""
+				if httpPushed {
+					transport = "http"
+				} else if pushMQTT {
+					transport = "mqtt"
+				}
+				if transport != "" && transport != lastTransport {
+					if transport == "http" {
+						log.Log.Info("cloud.HandleLiveStreamSD(): delivering preview frames over HTTP for device " + deviceId + ".")
+					} else {
+						reason := "viewer requested MQTT (older frontend)"
+						if httpViewerActive && snapshotPublisher == nil {
+							reason = "viewer asked for HTTP but Hub is not configured"
+						} else if httpViewerActive && httpErr != nil {
+							reason = "HTTP upload failed, falling back: " + httpErr.Error()
+						}
+						log.Log.Info("cloud.HandleLiveStreamSD(): delivering preview frames over MQTT for device " + deviceId + " (" + reason + ").")
+					}
+					lastTransport = transport
+				}
+
+				if pushMQTT {
+					log.Log.Debug("cloud.HandleLiveStreamSD(): Sending base64 encoded images to MQTT.")
 					chunking := config.Capture.LiveviewChunking
 
 					if chunking == "true" {

machinery/src/cloud/dropbox.go

@@ -46,7 +46,11 @@ func UploadDropbox(configuration *models.Configuration, fileName string) (bool,
 
 	file, err := os.OpenFile(fullname, os.O_RDWR, 0755)
 	if file != nil {
-		defer file.Close()
+		defer func() {
+			if cerr := file.Close(); cerr != nil {
+				log.Log.Error("UploadDropbox: Error closing file: " + cerr.Error())
+			}
+		}()
 	}
 
 	if err == nil {

machinery/src/cloud/kerberos_hub.go

@@ -34,6 +34,29 @@ func UploadKerberosHub(configuration *models.Configuration, fileName string) (bo
 
 	log.Log.Info("UploadKerberosHub: Uploading to Kerberos Hub (" + config.HubURI + ")")
 	log.Log.Info("UploadKerberosHub: Upload started for " + fileName)
+
+	// Prefer the resumable (tus) upload when enabled (the default). Kerberos Hub
+	// authenticates the agent with its Hub public/private key and proxies the
+	// resumable upload to the Kerberos Vault. When Hub does not expose a tus
+	// endpoint (older deployments) we transparently fall back to the legacy
+	// single-POST upload below.
+	if resumableUploadsEnabled() {
+		uploaded, _, supported, body, rerr := uploadHubResumable(&config, fileName, "UploadKerberosHub", "hub")
+		if supported {
+			if uploaded {
+				log.Log.Info("UploadKerberosHub: Upload Finished (resumable), " + body)
+				return true, true, nil
+			}
+			if rerr != nil {
+				log.Log.Info("UploadKerberosHub: resumable upload failed, " + rerr.Error())
+			} else {
+				log.Log.Info("UploadKerberosHub: resumable upload incomplete, " + body)
+			}
+			return false, true, rerr
+		}
+		log.Log.Info("UploadKerberosHub: resumable (tus) endpoint not available, falling back to legacy upload")
+	}
+
 	fullname := "data/recordings/" + fileName
 
 	// Check if we still have the file otherwise we abort the request.
@@ -68,9 +91,9 @@ func UploadKerberosHub(configuration *models.Configuration, fileName string) (bo
 		tr := &http.Transport{
 			TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
 		}
-		client = &http.Client{Transport: tr}
+		client = &http.Client{Transport: tr, CheckRedirect: stripHubCredentialsOnCrossHostRedirect}
 	} else {
-		client = &http.Client{}
+		client = &http.Client{CheckRedirect: stripHubCredentialsOnCrossHostRedirect}
 	}
 
 	resp, err := client.Do(req)
@@ -129,3 +152,20 @@ func UploadKerberosHub(configuration *models.Configuration, fileName string) (bo
 	log.Log.Info(errorMessage)
 	return false, true, errors.New(errorMessage)
 }
+
+// stripHubCredentialsOnCrossHostRedirect removes the custom Kerberos Hub
+// credential headers on a redirect that crosses to a different host. net/http
+// already strips the standard sensitive headers (Authorization, Cookie,
+// WWW-Authenticate) on a cross-host redirect, but it does NOT strip
+// custom-named headers, so without this the Hub private/public keys would be
+// forwarded to any host the configured HubURI redirects to.
+func stripHubCredentialsOnCrossHostRedirect(req *http.Request, via []*http.Request) error {
+	if len(via) == 0 {
+		return nil
+	}
+	if req.URL.Host != via[0].URL.Host {
+		req.Header.Del("X-Kerberos-Hub-PrivateKey")
+		req.Header.Del("X-Kerberos-Hub-PublicKey")
+	}
+	return nil
+}

machinery/src/cloud/kerberos_vault.go

@@ -30,6 +30,15 @@ func UploadKerberosVault(configuration *models.Configuration, fileName string) (
 		return false, false, errors.New(err)
 	}
 
+	// If the recording no longer exists on disk there is nothing to upload.
+	// This can happen when the file was already removed (e.g. cleanup, or an
+	// earlier successful upload). Skip it so the watcher drops the marker
+	// instead of retrying indefinitely.
+	if _, err := os.Stat("data/recordings/" + fileName); err != nil {
+		log.Log.Info("UploadKerberosVault: skipping " + fileName + ", file doesn't exist anymore")
+		return false, false, nil
+	}
+
 	// timestamp_microseconds_instanceName_regionCoordinates_numberOfChanges_token
 	// 1564859471_6-474162_oprit_577-283-727-375_1153_27.mp4
 	// - Timestamp
@@ -41,17 +50,6 @@ func UploadKerberosVault(configuration *models.Configuration, fileName string) (
 	// KerberosCloud, this means storage is disabled and proxy enabled.
 	log.Log.Info("UploadKerberosVault: Uploading to Kerberos Vault (" + config.KStorage.URI + ")")
 	log.Log.Info("UploadKerberosVault: Upload started for " + fileName)
-	fullname := "data/recordings/" + fileName
-
-	file, err := os.OpenFile(fullname, os.O_RDWR, 0755)
-	if file != nil {
-		defer file.Close()
-	}
-	if err != nil {
-		err := "UploadKerberosVault: Upload Failed, file doesn't exists anymore"
-		log.Log.Info(err)
-		return false, false, errors.New(err)
-	}
 
 	publicKey := config.KStorage.CloudKey
 	if config.HubKey != "" {
@@ -60,62 +58,30 @@ func UploadKerberosVault(configuration *models.Configuration, fileName string) (
 
 	// We need to check if we are in a retry timeout.
 	if kstorageRetryTimeout <= time.Now().Unix() {
+		uploaded, responded, body, err := sendToVault(*config.KStorage, publicKey, config.Key, fileName, "UploadKerberosVault", "primary")
+		if uploaded {
+			kstorageRetryCount = 0
+			log.Log.Info("UploadKerberosVault: Upload Finished, " + body)
+			return true, true, nil
+		}
 
-		req, err := http.NewRequest("POST", config.KStorage.URI+"/storage", file)
 		if err != nil {
-			errorMessage := "UploadKerberosVault: error reading request, " + config.KStorage.URI + "/storage: " + err.Error()
-			log.Log.Error(errorMessage)
-			return false, true, errors.New(errorMessage)
-		}
-		req.Header.Set("Content-Type", "video/mp4")
-		req.Header.Set("X-Kerberos-Storage-CloudKey", publicKey)
-		req.Header.Set("X-Kerberos-Storage-AccessKey", config.KStorage.AccessKey)
-		req.Header.Set("X-Kerberos-Storage-SecretAccessKey", config.KStorage.SecretAccessKey)
-		req.Header.Set("X-Kerberos-Storage-Provider", config.KStorage.Provider)
-		req.Header.Set("X-Kerberos-Storage-FileName", fileName)
-		req.Header.Set("X-Kerberos-Storage-Device", config.Key)
-		req.Header.Set("X-Kerberos-Storage-Capture", "IPCamera")
-		req.Header.Set("X-Kerberos-Storage-Directory", config.KStorage.Directory)
-
-		var client *http.Client
-		if os.Getenv("AGENT_TLS_INSECURE") == "true" {
-			tr := &http.Transport{
-				TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
-			}
-			client = &http.Client{Transport: tr}
-		} else {
-			client = &http.Client{}
-		}
-
-		resp, err := client.Do(req)
-		if resp != nil {
-			defer resp.Body.Close()
-		}
-
-		if err == nil {
-			if resp != nil {
-				body, err := io.ReadAll(resp.Body)
-				if err == nil {
-					if resp.StatusCode == 200 {
-						kstorageRetryCount = 0
-						log.Log.Info("UploadKerberosVault: Upload Finished, " + resp.Status + ", " + string(body))
-						return true, true, nil
-					} else {
-						// We increase the retry count, and set the timeout.
-						// If we have reached the retry policy, we set the timeout.
-						// This means we will not retry for the next 5 minutes.
-						if kstorageRetryCount < config.KStorage.MaxRetries {
-							kstorageRetryCount = (kstorageRetryCount + 1)
-						}
-						if kstorageRetryCount == config.KStorage.MaxRetries {
-							kstorageRetryTimeout = time.Now().Add(time.Duration(config.KStorage.Timeout) * time.Second).Unix()
-						}
-						log.Log.Info("UploadKerberosVault: Upload Failed, " + resp.Status + ", " + string(body))
-					}
-				}
-			}
-		} else {
 			log.Log.Info("UploadKerberosVault: Upload Failed, " + err.Error())
+		} else {
+			log.Log.Info("UploadKerberosVault: Upload Failed, " + body)
+		}
+
+		// We only advance the retry policy when the vault gave a definitive
+		// response (mirroring the original behaviour where transient network
+		// errors did not consume retries). When the retry count reaches the
+		// configured maximum we back off for the configured timeout.
+		if responded {
+			if kstorageRetryCount < config.KStorage.MaxRetries {
+				kstorageRetryCount = (kstorageRetryCount + 1)
+			}
+			if kstorageRetryCount == config.KStorage.MaxRetries {
+				kstorageRetryTimeout = time.Now().Add(time.Duration(config.KStorage.Timeout) * time.Second).Unix()
+			}
 		}
 	}
 
@@ -134,61 +100,116 @@ func UploadKerberosVault(configuration *models.Configuration, fileName string) (
 
 		log.Log.Info("UploadKerberosVault (Secondary): Uploading to Secondary Kerberos Vault (" + config.KStorageSecondary.URI + ")")
 
-		file, err = os.OpenFile(fullname, os.O_RDWR, 0755)
-		if file != nil {
-			defer file.Close()
-		}
-		if err != nil {
-			err := "UploadKerberosVault (Secondary): Upload Failed, file doesn't exists anymore"
-			log.Log.Info(err)
-			return false, false, errors.New(err)
+		uploaded, _, body, err := sendToVault(*config.KStorageSecondary, publicKey, config.Key, fileName, "UploadKerberosVault (Secondary)", "secondary")
+		if uploaded {
+			log.Log.Info("UploadKerberosVault (Secondary): Upload Finished to secondary, " + body)
+			return true, true, nil
 		}
 
-		req, err := http.NewRequest("POST", config.KStorageSecondary.URI+"/storage", file)
 		if err != nil {
-			errorMessage := "UploadKerberosVault (Secondary): error reading request, " + config.KStorageSecondary.URI + "/storage: " + err.Error()
-			log.Log.Error(errorMessage)
-			return false, true, errors.New(errorMessage)
-		}
-		req.Header.Set("Content-Type", "video/mp4")
-		req.Header.Set("X-Kerberos-Storage-CloudKey", publicKey)
-		req.Header.Set("X-Kerberos-Storage-AccessKey", config.KStorageSecondary.AccessKey)
-		req.Header.Set("X-Kerberos-Storage-SecretAccessKey", config.KStorageSecondary.SecretAccessKey)
-		req.Header.Set("X-Kerberos-Storage-Provider", config.KStorageSecondary.Provider)
-		req.Header.Set("X-Kerberos-Storage-FileName", fileName)
-		req.Header.Set("X-Kerberos-Storage-Device", config.Key)
-		req.Header.Set("X-Kerberos-Storage-Capture", "IPCamera")
-		req.Header.Set("X-Kerberos-Storage-Directory", config.KStorageSecondary.Directory)
-
-		var client *http.Client
-		if os.Getenv("AGENT_TLS_INSECURE") == "true" {
-			tr := &http.Transport{
-				TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
-			}
-			client = &http.Client{Transport: tr}
+			log.Log.Info("UploadKerberosVault (Secondary): Upload Failed to secondary, " + err.Error())
 		} else {
-			client = &http.Client{}
-		}
-
-		resp, err := client.Do(req)
-		if resp != nil {
-			defer resp.Body.Close()
-		}
-
-		if err == nil {
-			if resp != nil {
-				body, err := io.ReadAll(resp.Body)
-				if err == nil {
-					if resp.StatusCode == 200 {
-						log.Log.Info("UploadKerberosVault (Secondary): Upload Finished to secondary, " + resp.Status + ", " + string(body))
-						return true, true, nil
-					} else {
-						log.Log.Info("UploadKerberosVault (Secondary): Upload Failed to secondary, " + resp.Status + ", " + string(body))
-					}
-				}
-			}
+			log.Log.Info("UploadKerberosVault (Secondary): Upload Failed to secondary, " + body)
 		}
 	}
 
 	return false, true, nil
 }
+
+// sendToVault uploads a single recording to one Kerberos Vault. When resumable
+// uploads are enabled (the default) it attempts the tus protocol first and, if
+// the vault does not expose a tus endpoint (older deployments), transparently
+// falls back to the legacy single-shot POST.
+//
+// It returns whether the upload succeeded, whether the vault gave a definitive
+// HTTP response (so the caller can advance its retry policy), a short message
+// for logging, and a transport error if any.
+func sendToVault(vault models.KStorage, publicKey, deviceKey, fileName, label, slot string) (bool, bool, string, error) {
+	if resumableUploadsEnabled() {
+		uploaded, responded, supported, body, err := uploadVaultResumable(vault, publicKey, deviceKey, fileName, label, slot)
+		if supported {
+			return uploaded, responded, body, err
+		}
+		log.Log.Info(label + ": resumable (tus) endpoint not available, falling back to legacy upload")
+	}
+	return uploadVaultLegacy(vault, publicKey, deviceKey, fileName, label)
+}
+
+// uploadVaultLegacy performs the original single-request upload: the whole file
+// is sent as the body of a POST to {URI}/storage. Kept for backwards
+// compatibility with vault deployments that do not support resumable uploads.
+func uploadVaultLegacy(vault models.KStorage, publicKey, deviceKey, fileName, label string) (bool, bool, string, error) {
+	fullname := "data/recordings/" + fileName
+
+	file, err := os.Open(fullname)
+	if file != nil {
+		defer file.Close()
+	}
+	if err != nil {
+		msg := label + ": Upload Failed, file doesn't exists anymore"
+		log.Log.Info(msg)
+		return false, false, "", errors.New(msg)
+	}
+
+	uri := vault.URI
+	for len(uri) > 0 && uri[len(uri)-1] == '/' {
+		uri = uri[:len(uri)-1]
+	}
+
+	req, err := http.NewRequest("POST", uri+"/storage", file)
+	if err != nil {
+		errorMessage := label + ": error reading request, " + uri + "/storage: " + err.Error()
+		log.Log.Error(errorMessage)
+		return false, false, "", errors.New(errorMessage)
+	}
+	req.Header.Set("Content-Type", "video/mp4")
+	setVaultHeaders(req.Header, vault, publicKey, deviceKey, fileName)
+
+	client := newVaultHTTPClient(0)
+	resp, err := client.Do(req)
+	if resp != nil {
+		defer resp.Body.Close()
+	}
+	if err != nil {
+		return false, false, "", err
+	}
+
+	body, rerr := io.ReadAll(resp.Body)
+	if rerr != nil {
+		return false, false, "", rerr
+	}
+
+	if resp.StatusCode == 200 {
+		return true, true, resp.Status + ", " + string(body), nil
+	}
+	return false, true, resp.Status + ", " + string(body), nil
+}
+
+// setVaultHeaders sets the standard Kerberos Vault headers used by the legacy
+// single-POST upload.
+func setVaultHeaders(h http.Header, vault models.KStorage, publicKey, deviceKey, fileName string) {
+	h.Set("X-Kerberos-Storage-CloudKey", publicKey)
+	h.Set("X-Kerberos-Storage-AccessKey", vault.AccessKey)
+	h.Set("X-Kerberos-Storage-SecretAccessKey", vault.SecretAccessKey)
+	h.Set("X-Kerberos-Storage-Provider", vault.Provider)
+	h.Set("X-Kerberos-Storage-FileName", fileName)
+	h.Set("X-Kerberos-Storage-Device", deviceKey)
+	h.Set("X-Kerberos-Storage-Capture", "IPCamera")
+	h.Set("X-Kerberos-Storage-Directory", vault.Directory)
+}
+
+// newVaultHTTPClient builds an HTTP client honouring the AGENT_TLS_INSECURE
+// escape hatch. A timeout of 0 disables the client-level timeout, which is
+// required for streaming large upload bodies.
+func newVaultHTTPClient(timeout time.Duration) *http.Client {
+	client := &http.Client{}
+	if os.Getenv("AGENT_TLS_INSECURE") == "true" {
+		client.Transport = &http.Transport{
+			TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
+		}
+	}
+	if timeout > 0 {
+		client.Timeout = timeout
+	}
+	return client
+}

machinery/src/cloud/livehls.go

@@ -0,0 +1,261 @@
+package cloud
+
+import (
+	"os"
+	"time"
+
+	mqtt "github.com/eclipse/paho.mqtt.golang"
+
+	"github.com/kerberos-io/agent/machinery/src/capture"
+	"github.com/kerberos-io/agent/machinery/src/cloud/livehls"
+	"github.com/kerberos-io/agent/machinery/src/log"
+	"github.com/kerberos-io/agent/machinery/src/models"
+	"github.com/kerberos-io/agent/machinery/src/packets"
+)
+
+// hlsViewerTimeoutSeconds is how long the agent keeps shipping live HLS segments
+// after the last viewer keepalive. It is a few seconds longer than the segment
+// duration so a viewer whose keepalive is briefly delayed does not cause the
+// session to flap. When it lapses the session is torn down to stop wasting
+// upload bandwidth when nobody is watching.
+const hlsViewerTimeoutSeconds = 8
+
+// hlsReadyReannounceSeconds throttles how often the agent re-announces an
+// already-ready session over MQTT in response to viewer keepalives. The initial
+// "receive-hls-ready" is a one-shot fired when the first segment lands; a viewer
+// that connects or hard-refreshes after that (while the session is still alive)
+// missed it, so we re-announce on subsequent keepalives. Viewers dedupe by
+// session id, so a re-announce for a session they already play is a no-op. ~2s
+// gets a refreshed viewer playing well within its connection timeout without
+// spamming the control plane.
+const hlsReadyReannounceSeconds = 2
+
+// HandleLiveStreamHLS drives the live HLS producer. It mirrors HandleLiveStreamSD:
+// it reads the camera's packet stream from a Latest() cursor, and while a viewer
+// is active (kept alive via communication.HandleLiveHLS) it muxes the packets
+// into CMAF segments and ships them to hub-api, which stores each segment in an
+// ephemeral, short-TTL live window and serves the rolling playlist to viewers.
+//
+// A session is created lazily on the first keyframe seen while a viewer is active
+// and torn down once viewers go away, so an idle camera produces no live traffic.
+//
+// By default (AGENT_LIVE_HLS_PREWARM unset or != "false") the agent instead keeps
+// one long-lived session muxing continuously into a small in-memory ring buffer
+// while idle (uploading nothing) and, the moment a viewer arrives, flushes the
+// already-encoded init + most-recent segment(s) and starts uploading live. This
+// trades a little idle CPU for a near-instant "requesting stream", so viewers no
+// longer wait a full GOP for the first segment to be cut. Set
+// AGENT_LIVE_HLS_PREWARM=false to fall back to the lazy on-demand path above.
+func HandleLiveStreamHLS(livestreamCursor *packets.QueueCursor, configuration *models.Configuration, communication *models.Communication, mqttClient mqtt.Client, _ capture.RTSPClient) {
+
+	log.Log.Debug("cloud.HandleLiveStreamHLS(): started")
+
+	config := configuration.Config
+
+	if config.Offline == "true" {
+		log.Log.Debug("cloud.HandleLiveStreamHLS(): stopping as Offline is enabled.")
+		return
+	}
+	if config.Capture.Liveview == "false" {
+		log.Log.Debug("cloud.HandleLiveStreamHLS(): stopping as Liveview is disabled.")
+		return
+	}
+	if config.HubURI == "" || config.HubKey == "" {
+		log.Log.Debug("cloud.HandleLiveStreamHLS(): stopping as the Hub is not configured (HubURI/HubKey).")
+		return
+	}
+
+	hubKey := config.HubKey
+	deviceId := config.Key
+
+	region := ""
+	if config.S3 != nil {
+		region = config.S3.Region
+	}
+
+	publisher := livehls.NewPublisher(livehls.PublisherConfig{
+		HubURI:        config.HubURI,
+		HubKey:        config.HubKey,
+		HubPrivateKey: config.HubPrivateKey,
+		Region:        region,
+		DeviceKey:     deviceId,
+	})
+
+	// Encoded dimensions are only needed for the avcC fallback path (an SPS that
+	// mp4ff's strict parser rejects); the main stream dimensions are a safe value.
+	width := uint16(config.Capture.IPCamera.Width)
+	height := uint16(config.Capture.IPCamera.Height)
+
+	// prewarm keeps a single long-lived session muxing into an in-memory ring
+	// buffer while idle and flushes it the instant a viewer arrives, eliminating
+	// the per-request GOP wait. Enabled by default; set AGENT_LIVE_HLS_PREWARM=false
+	// to fall back to the lazy on-demand path.
+	prewarm := os.Getenv("AGENT_LIVE_HLS_PREWARM") != "false"
+	if prewarm {
+		log.Log.Info("cloud.HandleLiveStreamHLS(): live HLS prewarm ENABLED (set AGENT_LIVE_HLS_PREWARM=false to disable)")
+	} else {
+		log.Log.Info("cloud.HandleLiveStreamHLS(): live HLS prewarm DISABLED (AGENT_LIVE_HLS_PREWARM=false)")
+	}
+
+	// lowLatency enables LL-HLS: each segment is sliced into CMAF parts shipped the
+	// instant they close and advertised via #EXT-X-PART, taking glass-to-glass HLS
+	// latency from ~4-6s down to ~1-2s. Enabled by default; set
+	// AGENT_LIVE_HLS_LOW_LATENCY=false to fall back to whole-segment HLS.
+	partTargetMs := uint64(0)
+	if os.Getenv("AGENT_LIVE_HLS_LOW_LATENCY") != "false" {
+		partTargetMs = livehls.DefaultPartTargetMs
+		log.Log.Info("cloud.HandleLiveStreamHLS(): live HLS low-latency (LL-HLS) ENABLED (set AGENT_LIVE_HLS_LOW_LATENCY=false to disable)")
+	} else {
+		log.Log.Info("cloud.HandleLiveStreamHLS(): live HLS low-latency (LL-HLS) DISABLED (AGENT_LIVE_HLS_LOW_LATENCY=false)")
+	}
+
+	var session *livehls.Session
+	lastViewerRequest := int64(0)
+	lastReadyAnnounce := int64(0)
+
+	var cursorError error
+	var pkt packets.Packet
+
+	for cursorError == nil {
+		pkt, cursorError = livestreamCursor.ReadPacket()
+
+		now := time.Now().Unix()
+		select {
+		case <-communication.HandleLiveHLS:
+			lastViewerRequest = now
+			// A keepalive may come from a viewer that just connected or hard-
+			// refreshed and therefore missed the one-shot readiness announcement
+			// fired when this session's first segment landed. Re-announce (throttled)
+			// so late/refreshed viewers learn the active session id; the frontend
+			// dedupes by session id, so this is a no-op for viewers already playing.
+			// UploadsActive() is always true for the on-demand path; for prewarm it
+			// suppresses a stale re-announce while idle (the flush-on-arrival path
+			// below announces once the buffer has actually been shipped).
+			if session != nil && session.IsReady() && session.UploadsActive() && now-lastReadyAnnounce >= hlsReadyReannounceSeconds {
+				publishHLSReady(configuration, mqttClient, hubKey, deviceId, session.SessionID())
+				lastReadyAnnounce = now
+			}
+		default:
+		}
+
+		viewerActive := now-lastViewerRequest <= hlsViewerTimeoutSeconds
+
+		if prewarm {
+			// Keep one long-lived session muxing into the ring buffer. Create it on
+			// the first keyframe (so the buffer opens on a random-access point) and
+			// never tear it down for idleness; uploads, not muxing, are what we gate
+			// on viewer presence.
+			if session == nil {
+				if len(pkt.Data) == 0 || !pkt.IsVideo || !pkt.IsKeyFrame {
+					continue
+				}
+				session = livehls.NewSession(publisher, livehls.SessionOptions{
+					Codec:          pkt.Codec,
+					SPSNALUs:       config.Capture.IPCamera.SPSNALUs,
+					PPSNALUs:       config.Capture.IPCamera.PPSNALUs,
+					VPSNALUs:       config.Capture.IPCamera.VPSNALUs,
+					Width:          width,
+					Height:         height,
+					PartTargetMs:   partTargetMs,
+					StartBuffering: true,
+				})
+				session.SetOnReady(func(sessionID string) {
+					log.Log.Info("cloud.HandleLiveStreamHLS(): live HLS session ready, announcing " + sessionID)
+					publishHLSReady(configuration, mqttClient, hubKey, deviceId, sessionID)
+					lastReadyAnnounce = time.Now().Unix()
+				})
+				log.Log.Info("cloud.HandleLiveStreamHLS(): prewarming live HLS session " + session.SessionID())
+			}
+
+			if viewerActive {
+				// Activating flushes the cached init + buffered segment(s). onReady
+				// announces the first-ever readiness; on a later re-activation it has
+				// already fired, so announce here (throttled, so the first activation
+				// does not double up) once the buffer has actually been shipped.
+				if session.SetUploadsActive(true) && session.IsReady() && now-lastReadyAnnounce >= hlsReadyReannounceSeconds {
+					publishHLSReady(configuration, mqttClient, hubKey, deviceId, session.SessionID())
+					lastReadyAnnounce = now
+				}
+			} else {
+				// No viewer: keep muxing into the buffer but stop uploading.
+				session.SetUploadsActive(false)
+			}
+
+			if len(pkt.Data) > 0 && pkt.IsVideo {
+				if err := session.WritePacket(pkt); err != nil {
+					log.Log.Error("cloud.HandleLiveStreamHLS(): " + err.Error())
+				}
+			}
+			continue
+		}
+
+		if !viewerActive {
+			// No viewer: stop and discard the session so we stop shipping segments.
+			if session != nil {
+				_ = session.Close()
+				log.Log.Info("cloud.HandleLiveStreamHLS(): no active viewers, stopped live HLS session " + session.SessionID())
+				session = nil
+			}
+			continue
+		}
+
+		if len(pkt.Data) == 0 || !pkt.IsVideo {
+			continue
+		}
+
+		// Start a session lazily, but only on a keyframe so the first segment opens
+		// on a random-access point.
+		if session == nil {
+			if !pkt.IsKeyFrame {
+				continue
+			}
+			session = livehls.NewSession(publisher, livehls.SessionOptions{
+				Codec:        pkt.Codec,
+				SPSNALUs:     config.Capture.IPCamera.SPSNALUs,
+				PPSNALUs:     config.Capture.IPCamera.PPSNALUs,
+				VPSNALUs:     config.Capture.IPCamera.VPSNALUs,
+				Width:        width,
+				Height:       height,
+				PartTargetMs: partTargetMs,
+			})
+			session.SetOnReady(func(sessionID string) {
+				log.Log.Info("cloud.HandleLiveStreamHLS(): live HLS session ready, announcing " + sessionID)
+				publishHLSReady(configuration, mqttClient, hubKey, deviceId, sessionID)
+				lastReadyAnnounce = time.Now().Unix()
+			})
+			log.Log.Info("cloud.HandleLiveStreamHLS(): started live HLS session " + session.SessionID())
+		}
+
+		if err := session.WritePacket(pkt); err != nil {
+			log.Log.Error("cloud.HandleLiveStreamHLS(): " + err.Error())
+		}
+	}
+
+	if session != nil {
+		_ = session.Close()
+	}
+	log.Log.Debug("cloud.HandleLiveStreamHLS(): finished")
+}
+
+// publishHLSReady announces, over MQTT, that a live HLS session is available so
+// viewers can load the rolling playlist hub-api serves for {device}/{session}.
+func publishHLSReady(configuration *models.Configuration, mqttClient mqtt.Client, hubKey, deviceId, sessionID string) {
+	valueMap := map[string]interface{}{
+		"session": sessionID,
+		"device":  deviceId,
+	}
+	message := models.Message{
+		Payload: models.Payload{
+			Action:   "receive-hls-ready",
+			DeviceId: deviceId,
+			Value:    valueMap,
+		},
+	}
+	payload, err := models.PackageMQTTMessage(configuration, message)
+	if err == nil {
+		mqttClient.Publish("kerberos/hub/"+hubKey, 0, false, payload)
+		log.Log.Info("cloud.HandleLiveStreamHLS(): announced live HLS session " + sessionID)
+	} else {
+		log.Log.Error("cloud.HandleLiveStreamHLS(): failed to package receive-hls-ready message: " + err.Error())
+	}
+}

machinery/src/cloud/livehls/publisher.go

@@ -0,0 +1,236 @@
+// Package livehls implements the agent-side producer for live HLS streaming.
+//
+// It complements the recording pipeline: where recordings are muxed into one
+// fragmented MP4 and uploaded resumably (TUS) when complete, live HLS ships a
+// continuous series of small, independently-decodable CMAF segments to hub-api
+// the instant each is produced, so a browser can play a near-live HLS stream
+// without WebRTC/TURN (outbound HTTPS only).
+//
+// The wire contract (agent -> hub-api) intentionally mirrors the existing
+// header-based storage convention (X-Kerberos-Storage-Device / -FileName, plus
+// the Hub public/private key auth headers). hub-api authenticates the agent and
+// stores each segment in an ephemeral, short-TTL live window keyed by
+// {device}/{session}, which it serves straight back to the browser. The live
+// window is deliberately kept out of the vault and the recordings collection;
+// durable archival/DVR is a separate, later concern.
+//
+// Unlike recordings, live segments are NOT uploaded resumably: a 1-2s segment
+// that fails to upload is stale by the time a retry would land, so the publisher
+// is fire-and-forget and drops on failure (logged) rather than blocking the live
+// pipeline behind a retry/handshake.
+package livehls
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"net/http"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/kerberos-io/agent/machinery/src/log"
+	"github.com/kerberos-io/agent/machinery/src/video"
+)
+
+const (
+	// liveIngestPath is the hub-api endpoint that accepts a single live segment
+	// (or the init segment) and stores it in the ephemeral live window. hub-api
+	// distinguishes init vs media segment and the object name via the
+	// X-Kerberos-Live-* headers below, keeping a single route (mirrors the
+	// existing /storage/upload convention).
+	liveIngestPath = "/storage/live"
+
+	// Object names within a session. The init segment (ftyp+moov) is uploaded
+	// once per session; media segments are seg-<sequence>.m4s.
+	initObjectName = "init.mp4"
+
+	contentTypeInit    = "video/mp4"
+	contentTypeSegment = "video/iso.segment"
+
+	// Header names for the live ingest contract.
+	headerHubPublicKey  = "X-Kerberos-Hub-PublicKey"
+	headerHubPrivateKey = "X-Kerberos-Hub-PrivateKey"
+	headerHubRegion     = "X-Kerberos-Hub-Region"
+	headerStorageDevice = "X-Kerberos-Storage-Device"
+	headerLiveSession   = "X-Kerberos-Live-Session"
+	headerLiveName      = "X-Kerberos-Live-Name"
+	headerLiveSequence  = "X-Kerberos-Live-Sequence"
+	headerLiveDuration  = "X-Kerberos-Live-Duration"
+	// Low-latency (LL-HLS) part headers. A part belongs to media segment
+	// X-Kerberos-Live-Sequence and is the X-Kerberos-Live-Part-th chunk within it;
+	// X-Kerberos-Live-Part-Independent flags a part that starts on a keyframe.
+	headerLivePart            = "X-Kerberos-Live-Part"
+	headerLivePartIndependent = "X-Kerberos-Live-Part-Independent"
+
+	// defaultPublishTimeout bounds a single segment upload. A live segment that
+	// cannot be delivered within roughly its own duration is stale, so the upload
+	// is abandoned (dropped) rather than allowed to back up the pipeline.
+	defaultPublishTimeout = 4 * time.Second
+)
+
+// PublisherConfig carries the hub endpoint and credentials needed to ship live
+// segments. It is populated from the agent's models.Config (HubURI/HubKey/...).
+type PublisherConfig struct {
+	HubURI        string // base hub-api URL, e.g. https://api.hub.example.com
+	HubKey        string // Hub public key (X-Kerberos-Hub-PublicKey)
+	HubPrivateKey string // Hub private key (X-Kerberos-Hub-PrivateKey)
+	Region        string // storage region (X-Kerberos-Hub-Region), may be empty
+	DeviceKey     string // device/camera key (X-Kerberos-Storage-Device)
+
+	// Timeout optionally overrides defaultPublishTimeout (used by tests).
+	Timeout time.Duration
+	// HTTPClient optionally injects a client (used by tests). When nil a
+	// redirect-credential-stripping client is created.
+	HTTPClient *http.Client
+}
+
+// Publisher ships init and media segments to hub-api over plain HTTP POST.
+//
+// It is safe for sequential use from a single live-stream goroutine. Methods are
+// fire-and-forget: they return an error for the caller to log, but the caller is
+// expected to continue (drop-on-fail) rather than retry.
+type Publisher struct {
+	cfg    PublisherConfig
+	client *http.Client
+}
+
+// NewPublisher builds a Publisher. The HTTP client strips the Hub credential
+// headers on a cross-host redirect (net/http does this for standard auth headers
+// but not custom-named ones), matching the recording upload client.
+func NewPublisher(cfg PublisherConfig) *Publisher {
+	client := cfg.HTTPClient
+	if client == nil {
+		timeout := cfg.Timeout
+		if timeout <= 0 {
+			timeout = defaultPublishTimeout
+		}
+		client = &http.Client{
+			Timeout:       timeout,
+			CheckRedirect: stripHubCredentialsOnCrossHostRedirect,
+		}
+	}
+	return &Publisher{cfg: cfg, client: client}
+}
+
+// PublishInit uploads the session's init segment (ftyp+moov). It must be called
+// (and succeed) before the player can use any media segment, so the caller
+// should treat a failure here as "session not yet established" and retry on the
+// next init opportunity rather than shipping media segments blindly.
+func (p *Publisher) PublishInit(ctx context.Context, sessionID string, data []byte) error {
+	return p.post(ctx, postParams{
+		sessionID:   sessionID,
+		name:        initObjectName,
+		contentType: contentTypeInit,
+		body:        data,
+	})
+}
+
+// PublishSegment uploads one media segment (styp+moof+mdat). The segment's
+// sequence number and duration travel in headers so hub-api can update the
+// rolling playlist window without parsing the box structure.
+func (p *Publisher) PublishSegment(ctx context.Context, sessionID string, seg video.LiveSegment) error {
+	return p.post(ctx, postParams{
+		sessionID:   sessionID,
+		name:        fmt.Sprintf("seg-%d.m4s", seg.SequenceNumber),
+		sequence:    seg.SequenceNumber,
+		durationMs:  seg.DurationMs,
+		hasSegment:  true,
+		contentType: contentTypeSegment,
+		body:        seg.Data,
+	})
+}
+
+// PublishPart uploads one CMAF partial segment (LL-HLS). The part is named
+// seg-<segment>.<part>.m4s and carries its segment sequence, part index,
+// independence flag and duration in headers so hub-api can advertise it via
+// #EXT-X-PART and reconstruct the full segment by concatenating its parts.
+func (p *Publisher) PublishPart(ctx context.Context, sessionID string, part video.LivePart) error {
+	return p.post(ctx, postParams{
+		sessionID:   sessionID,
+		name:        fmt.Sprintf("seg-%d.%d.m4s", part.SegmentSeq, part.PartIndex),
+		sequence:    part.SegmentSeq,
+		durationMs:  part.DurationMs,
+		partIndex:   part.PartIndex,
+		independent: part.Independent,
+		hasPart:     true,
+		contentType: contentTypeSegment,
+		body:        part.Data,
+	})
+}
+
+type postParams struct {
+	sessionID   string
+	name        string
+	sequence    uint32
+	durationMs  uint64
+	hasSegment  bool
+	partIndex   uint32
+	independent bool
+	hasPart     bool
+	contentType string
+	body        []byte
+}
+
+// post performs a single fire-and-forget upload to the live ingest endpoint.
+func (p *Publisher) post(ctx context.Context, params postParams) error {
+	if p.cfg.HubURI == "" {
+		return fmt.Errorf("livehls: HubURI not configured")
+	}
+	if params.sessionID == "" {
+		return fmt.Errorf("livehls: empty session id")
+	}
+
+	url := strings.TrimRight(p.cfg.HubURI, "/") + liveIngestPath
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, bytes.NewReader(params.body))
+	if err != nil {
+		return fmt.Errorf("livehls: build request: %w", err)
+	}
+
+	req.Header.Set("Content-Type", params.contentType)
+	req.Header.Set(headerStorageDevice, p.cfg.DeviceKey)
+	req.Header.Set(headerLiveSession, params.sessionID)
+	req.Header.Set(headerLiveName, params.name)
+	if params.hasSegment || params.hasPart {
+		req.Header.Set(headerLiveSequence, strconv.FormatUint(uint64(params.sequence), 10))
+		req.Header.Set(headerLiveDuration, strconv.FormatUint(params.durationMs, 10))
+	}
+	if params.hasPart {
+		req.Header.Set(headerLivePart, strconv.FormatUint(uint64(params.partIndex), 10))
+		independent := "0"
+		if params.independent {
+			independent = "1"
+		}
+		req.Header.Set(headerLivePartIndependent, independent)
+	}
+	req.Header.Set(headerHubPublicKey, p.cfg.HubKey)
+	req.Header.Set(headerHubPrivateKey, p.cfg.HubPrivateKey)
+	req.Header.Set(headerHubRegion, p.cfg.Region)
+
+	resp, err := p.client.Do(req)
+	if err != nil {
+		return fmt.Errorf("livehls: upload %s: %w", params.name, err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		return fmt.Errorf("livehls: upload %s rejected: %s", params.name, resp.Status)
+	}
+	log.Log.Debug("livehls.Publisher.post(): shipped " + params.name + " for session " + params.sessionID)
+	return nil
+}
+
+// stripHubCredentialsOnCrossHostRedirect removes the Hub credential headers when
+// a redirect crosses to a different host. net/http strips standard sensitive
+// headers on a cross-host redirect but not custom-named ones, so without this the
+// Hub keys could leak to a redirect target.
+func stripHubCredentialsOnCrossHostRedirect(req *http.Request, via []*http.Request) error {
+	if len(via) == 0 {
+		return nil
+	}
+	if req.URL.Host != via[0].URL.Host {
+		req.Header.Del(headerHubPrivateKey)
+		req.Header.Del(headerHubPublicKey)
+	}
+	return nil
+}

machinery/src/cloud/livehls/publisher_test.go

@@ -0,0 +1,312 @@
+package livehls
+
+import (
+	"context"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/kerberos-io/agent/machinery/src/packets"
+	"github.com/kerberos-io/agent/machinery/src/video"
+)
+
+// captured records one received upload for assertions.
+type captured struct {
+	path        string
+	method      string
+	contentType string
+	device      string
+	session     string
+	name        string
+	sequence    string
+	duration    string
+	hubPublic   string
+	hubPrivate  string
+	region      string
+	body        []byte
+}
+
+// newCapturingServer returns an httptest server that records every upload and
+// replies with the given status code.
+func newCapturingServer(t *testing.T, status int) (*httptest.Server, *[]captured, *sync.Mutex) {
+	t.Helper()
+	var mu sync.Mutex
+	var got []captured
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		body, _ := io.ReadAll(r.Body)
+		mu.Lock()
+		got = append(got, captured{
+			path:        r.URL.Path,
+			method:      r.Method,
+			contentType: r.Header.Get("Content-Type"),
+			device:      r.Header.Get(headerStorageDevice),
+			session:     r.Header.Get(headerLiveSession),
+			name:        r.Header.Get(headerLiveName),
+			sequence:    r.Header.Get(headerLiveSequence),
+			duration:    r.Header.Get(headerLiveDuration),
+			hubPublic:   r.Header.Get(headerHubPublicKey),
+			hubPrivate:  r.Header.Get(headerHubPrivateKey),
+			region:      r.Header.Get(headerHubRegion),
+			body:        body,
+		})
+		mu.Unlock()
+		w.WriteHeader(status)
+	}))
+	t.Cleanup(srv.Close)
+	return srv, &got, &mu
+}
+
+func testPublisher(hubURI string) *Publisher {
+	return NewPublisher(PublisherConfig{
+		HubURI:        hubURI,
+		HubKey:        "pub-key",
+		HubPrivateKey: "priv-key",
+		Region:        "eu-west",
+		DeviceKey:     "cam-1",
+		Timeout:       2 * time.Second,
+	})
+}
+
+func TestPublisherPublishInitSendsContractHeaders(t *testing.T) {
+	srv, got, mu := newCapturingServer(t, http.StatusOK)
+	p := testPublisher(srv.URL)
+
+	if err := p.PublishInit(context.Background(), "sess-1", []byte("INITBYTES")); err != nil {
+		t.Fatalf("PublishInit: %v", err)
+	}
+
+	mu.Lock()
+	defer mu.Unlock()
+	if len(*got) != 1 {
+		t.Fatalf("server received %d requests, want 1", len(*got))
+	}
+	c := (*got)[0]
+	if c.method != http.MethodPost {
+		t.Errorf("method=%s, want POST", c.method)
+	}
+	if c.path != liveIngestPath {
+		t.Errorf("path=%s, want %s", c.path, liveIngestPath)
+	}
+	if c.contentType != contentTypeInit {
+		t.Errorf("content-type=%s, want %s", c.contentType, contentTypeInit)
+	}
+	if c.device != "cam-1" {
+		t.Errorf("device=%s, want cam-1", c.device)
+	}
+	if c.session != "sess-1" {
+		t.Errorf("session=%s, want sess-1", c.session)
+	}
+	if c.name != initObjectName {
+		t.Errorf("name=%s, want %s", c.name, initObjectName)
+	}
+	if c.hubPublic != "pub-key" || c.hubPrivate != "priv-key" || c.region != "eu-west" {
+		t.Errorf("auth headers wrong: pub=%q priv=%q region=%q", c.hubPublic, c.hubPrivate, c.region)
+	}
+	if string(c.body) != "INITBYTES" {
+		t.Errorf("body=%q, want INITBYTES", string(c.body))
+	}
+	// init must NOT carry segment-only headers.
+	if c.sequence != "" || c.duration != "" {
+		t.Errorf("init should not send sequence/duration, got seq=%q dur=%q", c.sequence, c.duration)
+	}
+}
+
+func TestPublisherPublishSegmentSendsSequenceAndDuration(t *testing.T) {
+	srv, got, mu := newCapturingServer(t, http.StatusOK)
+	p := testPublisher(srv.URL)
+
+	seg := video.LiveSegment{SequenceNumber: 7, DurationMs: 1960, Data: []byte("SEGMENT")}
+	if err := p.PublishSegment(context.Background(), "sess-9", seg); err != nil {
+		t.Fatalf("PublishSegment: %v", err)
+	}
+
+	mu.Lock()
+	defer mu.Unlock()
+	c := (*got)[0]
+	if c.contentType != contentTypeSegment {
+		t.Errorf("content-type=%s, want %s", c.contentType, contentTypeSegment)
+	}
+	if c.name != "seg-7.m4s" {
+		t.Errorf("name=%s, want seg-7.m4s", c.name)
+	}
+	if c.sequence != "7" {
+		t.Errorf("sequence=%s, want 7", c.sequence)
+	}
+	if c.duration != "1960" {
+		t.Errorf("duration=%s, want 1960", c.duration)
+	}
+	if string(c.body) != "SEGMENT" {
+		t.Errorf("body=%q, want SEGMENT", string(c.body))
+	}
+}
+
+func TestPublisherReturnsErrorOnNon2xx(t *testing.T) {
+	srv, _, _ := newCapturingServer(t, http.StatusInternalServerError)
+	p := testPublisher(srv.URL)
+
+	err := p.PublishSegment(context.Background(), "s", video.LiveSegment{SequenceNumber: 1, Data: []byte("x")})
+	if err == nil {
+		t.Fatal("expected an error on 500 response")
+	}
+}
+
+func TestPublisherErrorsWithoutHubURI(t *testing.T) {
+	p := NewPublisher(PublisherConfig{DeviceKey: "cam"})
+	if err := p.PublishInit(context.Background(), "s", []byte("x")); err == nil {
+		t.Fatal("expected error when HubURI is empty")
+	}
+}
+
+// makeAnnexBVideoPacket builds a synthetic capture packet carrying one Annex B
+// H.264 access unit at the given decode time (ms).
+func makeAnnexBVideoPacket(isKey bool, timeMs int64) packets.Packet {
+	nalType := byte(0x01)
+	if isKey {
+		nalType = 0x65
+	}
+	data := []byte{0x00, 0x00, 0x00, 0x01, nalType}
+	for i := 0; i < 80; i++ {
+		data = append(data, byte(i))
+	}
+	return packets.Packet{
+		IsVideo:    true,
+		IsKeyFrame: isKey,
+		Codec:      "H264",
+		Data:       data,
+		TimeLegacy: time.Duration(timeMs) * time.Millisecond,
+	}
+}
+
+func TestSessionShipsInitThenSegmentsAndFiresReady(t *testing.T) {
+	srv, got, mu := newCapturingServer(t, http.StatusOK)
+	p := testPublisher(srv.URL)
+
+	sess := NewSession(p, SessionOptions{
+		Codec:           "H264",
+		SPSNALUs:        [][]byte{liveTestSPSForSession()},
+		PPSNALUs:        [][]byte{{0x68, 0xce, 0x38, 0x80}},
+		Width:           640,
+		Height:          480,
+		TargetSegmentMs: 2000,
+	})
+
+	var readyCalls int
+	var readySession string
+	sess.SetOnReady(func(id string) {
+		readyCalls++
+		readySession = id
+	})
+
+	// 4 GOPs of 25 frames @ 40ms = 1s GOPs => with 2s target, 2 segments emitted
+	// during streaming and a final one on Close.
+	const gopFrames, gops = 25, 4
+	for i := 0; i < gopFrames*gops; i++ {
+		isKey := i%gopFrames == 0
+		pkt := makeAnnexBVideoPacket(isKey, int64(i*40))
+		if err := sess.WritePacket(pkt); err != nil {
+			t.Fatalf("WritePacket(%d): %v", i, err)
+		}
+	}
+	// A non-video packet must be ignored.
+	if err := sess.WritePacket(packets.Packet{IsAudio: true, Data: []byte{1, 2, 3}}); err != nil {
+		t.Fatalf("WritePacket(audio): %v", err)
+	}
+	if err := sess.Close(); err != nil {
+		t.Fatalf("Close: %v", err)
+	}
+
+	mu.Lock()
+	defer mu.Unlock()
+
+	var initCount, segCount int
+	for _, c := range *got {
+		if c.name == initObjectName {
+			initCount++
+			if string(c.body[4:8]) != "ftyp" {
+				t.Errorf("init body is not an ftyp box: % x", c.body[:12])
+			}
+		} else {
+			segCount++
+			if c.session != sess.SessionID() {
+				t.Errorf("segment session=%s, want %s", c.session, sess.SessionID())
+			}
+		}
+	}
+	if initCount != 1 {
+		t.Errorf("init uploaded %d times, want exactly 1", initCount)
+	}
+	if segCount < 2 {
+		t.Errorf("got %d segment uploads, want >= 2", segCount)
+	}
+	if readyCalls != 1 {
+		t.Errorf("OnReady fired %d times, want exactly 1", readyCalls)
+	}
+	if readySession != sess.SessionID() {
+		t.Errorf("OnReady session=%s, want %s", readySession, sess.SessionID())
+	}
+}
+
+func TestSessionRetriesInitWhenFirstAttemptFails(t *testing.T) {
+	// Server fails the first N requests, then succeeds. This proves init is
+	// re-attempted (not dropped) so the session can still establish.
+	var mu sync.Mutex
+	var inits, segs int
+	failFirst := 1
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		mu.Lock()
+		defer mu.Unlock()
+		name := r.Header.Get(headerLiveName)
+		if name == initObjectName {
+			inits++
+			if inits <= failFirst {
+				w.WriteHeader(http.StatusBadGateway)
+				return
+			}
+		} else {
+			segs++
+		}
+		w.WriteHeader(http.StatusOK)
+	}))
+	t.Cleanup(srv.Close)
+
+	sess := NewSession(testPublisher(srv.URL), SessionOptions{
+		Codec:    "H264",
+		SPSNALUs: [][]byte{liveTestSPSForSession()},
+		PPSNALUs: [][]byte{{0x68, 0xce, 0x38, 0x80}},
+		Width:    640,
+		Height:   480,
+	})
+
+	var ready int
+	sess.SetOnReady(func(string) { ready++ })
+
+	for i := 0; i < 60; i++ {
+		isKey := i%25 == 0
+		if err := sess.WritePacket(makeAnnexBVideoPacket(isKey, int64(i*40))); err != nil {
+			t.Fatalf("WritePacket(%d): %v", i, err)
+		}
+	}
+	if err := sess.Close(); err != nil {
+		t.Fatalf("Close: %v", err)
+	}
+
+	mu.Lock()
+	defer mu.Unlock()
+	if inits < 2 {
+		t.Errorf("init attempted %d times, want >= 2 (first failed then retried)", inits)
+	}
+	if segs < 1 {
+		t.Errorf("no segments delivered after init recovered (segs=%d)", segs)
+	}
+	if ready != 1 {
+		t.Errorf("OnReady fired %d times, want 1", ready)
+	}
+}
+
+// liveTestSPSForSession is the known-good baseline SPS reused across tests.
+func liveTestSPSForSession() []byte {
+	return []byte{0x67, 0x42, 0xc0, 0x1e, 0xd9, 0x00, 0xa0, 0x47, 0xfe, 0xc8}
+}

machinery/src/cloud/livehls/session.go

@@ -0,0 +1,457 @@
+package livehls
+
+import (
+	"context"
+	"crypto/rand"
+	"encoding/hex"
+	"fmt"
+	"sync"
+	"time"
+
+	"github.com/kerberos-io/agent/machinery/src/log"
+	"github.com/kerberos-io/agent/machinery/src/packets"
+	"github.com/kerberos-io/agent/machinery/src/video"
+)
+
+// DefaultTargetSegmentMs is the nominal live segment length. ~2s keeps standard
+// HLS latency reasonable (a player typically buffers ~3 segments) while staying
+// large enough that per-segment HTTP overhead is negligible.
+const DefaultTargetSegmentMs = 2000
+
+// DefaultPartTargetMs is the nominal LL-HLS part length used when low latency is
+// enabled. ~300ms parts yield ~6-7 parts per 2s segment; with the playlist's
+// PART-HOLD-BACK at ~3x the part target this lands glass-to-glass latency around
+// 1-2s (versus ~4-6s for whole-segment HLS).
+const DefaultPartTargetMs = 300
+
+// Session ties a video.LiveSegmenter to a Publisher: it converts capture packets
+// into CMAF segments and ships each one to hub-api. Exactly one init segment is
+// delivered per session (re-attempted until it lands), after which media
+// segments are published and the OnReady signal fires once so the control plane
+// (MQTT) can tell viewers the live playlist exists.
+//
+// A Session is driven from a single goroutine (the live-stream loop); its methods
+// are not safe for concurrent use except SessionID, which is immutable.
+type Session struct {
+	id        string
+	publisher *Publisher
+	segmenter *video.LiveSegmenter
+
+	// newContext produces the per-upload context (timeout). Overridable in tests.
+	newContext func() (context.Context, context.CancelFunc)
+
+	mu            sync.Mutex
+	initBytes     []byte
+	initPublished bool
+	// lastInitAt is when the init segment was last (re)uploaded. The init is
+	// re-sent periodically so its short TTL in the hub live window never lapses
+	// mid-session; see refreshInitIfStale.
+	lastInitAt time.Time
+	readyFired bool
+	onReady    func(sessionID string)
+
+	// uploadsActive gates whether the init and completed segments are shipped to
+	// hub-api. It is true for the default on-demand path. The prewarm path starts
+	// it false so the session keeps muxing into bufferedSegments without producing
+	// any live traffic until a viewer actually arrives; see SetUploadsActive.
+	uploadsActive bool
+	// bufferedSegments is the in-memory ring buffer (the most recent
+	// prewarmMaxBufferedSegments segments) kept while uploadsActive is false, so a
+	// viewer that arrives can be served an already-encoded segment immediately
+	// instead of waiting a full GOP for the next one to be cut.
+	bufferedSegments []video.LiveSegment
+	// bufferedParts is the LL-HLS counterpart of bufferedSegments: while idle it
+	// retains the parts of the most recent (prewarmMaxBufferedSegments+1) segments,
+	// pruned a WHOLE segment at a time so a flushed segment is never partial.
+	bufferedParts []video.LivePart
+}
+
+// SessionOptions configures a live HLS session.
+type SessionOptions struct {
+	Codec           string   // "H264" or "H265"
+	SPSNALUs        [][]byte // parameter sets (raw or Annex B)
+	PPSNALUs        [][]byte //
+	VPSNALUs        [][]byte // H.265 only
+	Width           uint16   // encoded width (for the avcC fallback path)
+	Height          uint16   // encoded height
+	TargetSegmentMs uint64   // 0 => DefaultTargetSegmentMs
+	// PartTargetMs, when > 0, enables LL-HLS: each segment is additionally sliced
+	// into ~PartTargetMs CMAF parts that are published (and advertised via
+	// #EXT-X-PART) the instant they close, for ~1-2s glass-to-glass latency. 0
+	// keeps the classic whole-segment path.
+	PartTargetMs uint64
+	// StartBuffering starts the session in prewarm (buffer-only) mode: it muxes
+	// segments into an in-memory ring buffer but uploads nothing until
+	// SetUploadsActive(true) is called. Default false => uploads are live
+	// immediately (the on-demand path's behaviour).
+	StartBuffering bool
+}
+
+// NewSession builds a session with a fresh random id and wires the segmenter's
+// init/segment callbacks to the publisher.
+func NewSession(publisher *Publisher, opts SessionOptions) *Session {
+	target := opts.TargetSegmentMs
+	if target == 0 {
+		target = DefaultTargetSegmentMs
+	}
+	seg := video.NewLiveSegmenter(opts.Codec, opts.SPSNALUs, opts.PPSNALUs, opts.VPSNALUs, target)
+	seg.SetDimensions(opts.Width, opts.Height)
+	if opts.PartTargetMs > 0 {
+		seg.EnableLowLatency(opts.PartTargetMs)
+	}
+
+	s := &Session{
+		id:        newSessionID(),
+		publisher: publisher,
+		segmenter: seg,
+		// Uploads are live by default; the prewarm path opts into buffer-only mode.
+		uploadsActive: !opts.StartBuffering,
+		newContext: func() (context.Context, context.CancelFunc) {
+			return context.WithTimeout(context.Background(), defaultPublishTimeout)
+		},
+	}
+
+	// The segmenter emits the init segment exactly once; capture it and try to
+	// ship it. Failures here are non-fatal - publishInitIfNeeded re-attempts
+	// before the next media segment so a transient hub hiccup at startup does not
+	// permanently break the session.
+	seg.OnInit = func(initBytes []byte) error {
+		s.mu.Lock()
+		s.initBytes = append([]byte(nil), initBytes...)
+		active := s.uploadsActive
+		s.mu.Unlock()
+		// While prewarming we cache the init in memory but ship nothing; it is
+		// uploaded on the first SetUploadsActive(true) flush.
+		if active {
+			s.publishInitIfNeeded()
+		}
+		return nil
+	}
+
+	// Each completed media segment is shipped. We only publish a segment once the
+	// init segment has landed (a media segment is useless without it), and we fire
+	// OnReady after the first successfully shipped segment.
+	seg.OnSegment = func(segment video.LiveSegment) error {
+		s.mu.Lock()
+		active := s.uploadsActive
+		s.mu.Unlock()
+		if !active {
+			// Prewarm: retain the most recent segments in memory but upload nothing
+			// until a viewer arrives (SetUploadsActive flushes them).
+			s.bufferSegment(segment)
+			return nil
+		}
+		if !s.publishInitIfNeeded() {
+			log.Log.Warning("livehls.Session: dropping segment " +
+				fmt.Sprintf("%d", segment.SequenceNumber) + " because init has not been delivered yet")
+			return nil
+		}
+		ctx, cancel := s.newContext()
+		defer cancel()
+		if err := s.publisher.PublishSegment(ctx, s.id, segment); err != nil {
+			log.Log.Warning("livehls.Session: " + err.Error())
+			return nil
+		}
+		s.fireReadyOnce()
+		// Keep the (write-once) init segment from ageing out of the live window
+		// while the session is still producing media.
+		s.refreshInitIfStale()
+		return nil
+	}
+
+	// In LL-HLS mode the segmenter emits parts (not whole segments); ship each one
+	// the instant it closes. Mirrors OnSegment: buffer while prewarming, otherwise
+	// publish after the init has landed and fire OnReady on the first part.
+	if opts.PartTargetMs > 0 {
+		seg.OnPart = func(part video.LivePart) error {
+			s.mu.Lock()
+			active := s.uploadsActive
+			s.mu.Unlock()
+			if !active {
+				s.bufferPart(part)
+				return nil
+			}
+			if !s.publishInitIfNeeded() {
+				log.Log.Warning("livehls.Session: dropping part " +
+					fmt.Sprintf("%d.%d", part.SegmentSeq, part.PartIndex) +
+					" because init has not been delivered yet")
+				return nil
+			}
+			ctx, cancel := s.newContext()
+			defer cancel()
+			if err := s.publisher.PublishPart(ctx, s.id, part); err != nil {
+				log.Log.Warning("livehls.Session: " + err.Error())
+				return nil
+			}
+			s.fireReadyOnce()
+			s.refreshInitIfStale()
+			return nil
+		}
+	}
+
+	return s
+}
+
+// SessionID returns the immutable session identifier used in object keys and the
+// MQTT ready signal.
+func (s *Session) SessionID() string { return s.id }
+
+// IsReady reports whether the session has delivered its init segment and at
+// least one media segment, i.e. the playlist hub-api serves is now playable. It
+// lets the live-stream loop re-announce "receive-hls-ready" to viewers that join
+// or hard-refresh after the initial one-shot signal (which they would otherwise
+// never receive, leaving the stream blank until the session is recreated).
+func (s *Session) IsReady() bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.readyFired
+}
+
+// SetOnReady registers a callback fired exactly once, after the first media
+// segment has been successfully delivered. Used to publish the MQTT
+// "receive-hls-ready" signal so viewers can load the playlist.
+func (s *Session) SetOnReady(fn func(sessionID string)) {
+	s.mu.Lock()
+	s.onReady = fn
+	s.mu.Unlock()
+}
+
+// prewarmMaxBufferedSegments is how many of the most recent completed segments
+// the prewarm path keeps in memory while idle and flushes to a viewer on arrival.
+// One segment keeps startup instant (the viewer immediately gets a playable
+// segment) while starting as close to the live edge as possible, so the HLS view
+// tracks the WebRTC/live edge instead of opening several seconds behind; hls.js
+// then converges to the edge via maxLiveSyncPlaybackRate. Raising it trades
+// latency-from-live for a little more startup cushion.
+const prewarmMaxBufferedSegments = 1
+
+// SetUploadsActive toggles whether the session ships its init and segments to
+// hub-api, and reports whether this call flipped it from inactive to active.
+//
+// While uploads are inactive the session keeps muxing capture packets into an
+// in-memory ring buffer (the cached init plus the most recent
+// prewarmMaxBufferedSegments segments) but uploads nothing, so an idle camera
+// produces no live traffic. Switching from inactive to active immediately
+// flushes the cached init and buffered segments so a viewer can start almost
+// instantly instead of waiting a full GOP for the next segment to be cut.
+// Switching from active to inactive resets the init-published flag so the next
+// activation re-uploads the init (it may have aged out of the hub's short-TTL
+// live window while idle). All other transitions are no-ops. Driven from the
+// live-stream goroutine; not safe for concurrent use.
+func (s *Session) SetUploadsActive(active bool) bool {
+	s.mu.Lock()
+	if s.uploadsActive == active {
+		s.mu.Unlock()
+		return false
+	}
+	s.uploadsActive = active
+	if !active {
+		// Going idle: force the next activation to re-deliver the init segment,
+		// which may have expired from the hub live window while nobody was watching.
+		s.initPublished = false
+		s.mu.Unlock()
+		return false
+	}
+	// Inactive -> active: take the cached buffered segments/parts and flush them
+	// outside the lock (the publish calls take their own time and re-acquire the
+	// mutex).
+	buffered := s.bufferedSegments
+	bufferedParts := s.bufferedParts
+	s.bufferedSegments = nil
+	s.bufferedParts = nil
+	s.mu.Unlock()
+
+	// Deliver the init first; media segments are useless without it.
+	for i := range buffered {
+		if !s.publishInitIfNeeded() {
+			break
+		}
+		ctx, cancel := s.newContext()
+		if err := s.publisher.PublishSegment(ctx, s.id, buffered[i]); err != nil {
+			log.Log.Warning("livehls.Session: prewarm flush: " + err.Error())
+			cancel()
+			continue
+		}
+		cancel()
+		s.fireReadyOnce()
+		s.refreshInitIfStale()
+	}
+	// LL-HLS: flush the buffered parts in order (oldest first) so the viewer gets a
+	// playable, near-live window immediately.
+	for i := range bufferedParts {
+		if !s.publishInitIfNeeded() {
+			break
+		}
+		ctx, cancel := s.newContext()
+		if err := s.publisher.PublishPart(ctx, s.id, bufferedParts[i]); err != nil {
+			log.Log.Warning("livehls.Session: prewarm flush (part): " + err.Error())
+			cancel()
+			continue
+		}
+		cancel()
+		s.fireReadyOnce()
+		s.refreshInitIfStale()
+	}
+	return true
+}
+
+// UploadsActive reports whether the session is currently shipping segments (as
+// opposed to buffering them while prewarming). Always true for the on-demand
+// path.
+func (s *Session) UploadsActive() bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.uploadsActive
+}
+
+// bufferSegment appends a completed segment to the in-memory prewarm ring buffer,
+// discarding the oldest so at most prewarmMaxBufferedSegments are retained.
+func (s *Session) bufferSegment(seg video.LiveSegment) {
+	s.mu.Lock()
+	s.bufferedSegments = append(s.bufferedSegments, seg)
+	if overflow := len(s.bufferedSegments) - prewarmMaxBufferedSegments; overflow > 0 {
+		// Drop the oldest segment(s) and shrink the backing array so retained bytes
+		// stay bounded.
+		s.bufferedSegments = append([]video.LiveSegment(nil), s.bufferedSegments[overflow:]...)
+	}
+	s.mu.Unlock()
+}
+
+// bufferPart appends a part to the LL-HLS prewarm ring buffer, pruning whole
+// older segments (never individual parts) so the retained window always consists
+// of complete segments plus the in-progress one. Pruning on a part-0 boundary
+// keeps at most prewarmMaxBufferedSegments fully-buffered segments behind the
+// current one, which guarantees a flushed segment can be reconstructed in full.
+func (s *Session) bufferPart(part video.LivePart) {
+	s.mu.Lock()
+	s.bufferedParts = append(s.bufferedParts, part)
+	if part.PartIndex == 0 && part.SegmentSeq > uint32(prewarmMaxBufferedSegments) {
+		minSeg := part.SegmentSeq - uint32(prewarmMaxBufferedSegments)
+		kept := make([]video.LivePart, 0, len(s.bufferedParts))
+		for _, p := range s.bufferedParts {
+			if p.SegmentSeq >= minSeg {
+				kept = append(kept, p)
+			}
+		}
+		s.bufferedParts = kept
+	}
+	s.mu.Unlock()
+}
+
+// WritePacket feeds one capture packet into the segmenter. Non-video packets are
+// ignored (the spike is video-only). The decode timestamp is derived exactly as
+// the recording muxer does: DTS = PTS - compositionOffset, with the composition
+// offset forwarded for correct B-frame presentation order.
+func (s *Session) WritePacket(pkt packets.Packet) error {
+	if !pkt.IsVideo {
+		return nil
+	}
+	pts := uint64(pkt.TimeLegacy.Milliseconds())
+	compositionOffset := pkt.CompositionTime
+	dts := pts
+	if compositionOffset > 0 && uint64(compositionOffset) <= pts {
+		dts = pts - uint64(compositionOffset)
+	} else if compositionOffset < 0 || uint64(compositionOffset) > pts {
+		// Guard against invalid offsets to avoid producing a CTS (DTS+CTO) jump.
+		compositionOffset = 0
+	}
+	return s.segmenter.WriteSample(pkt.IsKeyFrame, pkt.Data, dts, int32(compositionOffset))
+}
+
+// Close flushes any buffered sample and ships the final segment.
+func (s *Session) Close() error {
+	return s.segmenter.Close()
+}
+
+// publishInitIfNeeded ensures the init segment has been delivered, attempting an
+// upload if it has not. Returns true once init is known to be published.
+func (s *Session) publishInitIfNeeded() bool {
+	s.mu.Lock()
+	if s.initPublished {
+		s.mu.Unlock()
+		return true
+	}
+	initBytes := s.initBytes
+	s.mu.Unlock()
+
+	if len(initBytes) == 0 {
+		return false
+	}
+
+	ctx, cancel := s.newContext()
+	defer cancel()
+	if err := s.publisher.PublishInit(ctx, s.id, initBytes); err != nil {
+		log.Log.Warning("livehls.Session: init upload failed, will retry: " + err.Error())
+		return false
+	}
+
+	s.mu.Lock()
+	s.initPublished = true
+	s.lastInitAt = time.Now()
+	s.mu.Unlock()
+	log.Log.Info("livehls.Session: init segment delivered for session " + s.id)
+	return true
+}
+
+// initRefreshInterval is how often the init segment is re-uploaded so its TTL in
+// the hub-api live window never lapses mid-session. The init segment is otherwise
+// written only once per session; because the live window expires objects after a
+// short TTL (LiveSegmentTTLSeconds, 45s on the hub) the init would age out after
+// ~1 minute and the playlist's #EXT-X-MAP would start 404ing, stalling playback.
+// Re-uploading well inside that TTL keeps the init alive for the life of the
+// session while still letting it expire naturally once the session ends.
+const initRefreshInterval = 15 * time.Second
+
+// refreshInitIfStale re-uploads the init segment if it has not been refreshed
+// within initRefreshInterval, keeping its created_at (and thus its TTL) current
+// for as long as the session is producing segments. It is a no-op until the init
+// has first been published. Failures are non-fatal: the next segment retries.
+func (s *Session) refreshInitIfStale() {
+	s.mu.Lock()
+	if !s.initPublished || time.Since(s.lastInitAt) < initRefreshInterval {
+		s.mu.Unlock()
+		return
+	}
+	initBytes := s.initBytes
+	s.mu.Unlock()
+
+	if len(initBytes) == 0 {
+		return
+	}
+
+	ctx, cancel := s.newContext()
+	defer cancel()
+	if err := s.publisher.PublishInit(ctx, s.id, initBytes); err != nil {
+		log.Log.Warning("livehls.Session: init refresh failed, will retry: " + err.Error())
+		return
+	}
+
+	s.mu.Lock()
+	s.lastInitAt = time.Now()
+	s.mu.Unlock()
+	log.Log.Debug("livehls.Session: refreshed init segment TTL for session " + s.id)
+}
+
+// fireReadyOnce invokes the OnReady callback the first time it is called.
+func (s *Session) fireReadyOnce() {
+	s.mu.Lock()
+	if s.readyFired || s.onReady == nil {
+		s.mu.Unlock()
+		return
+	}
+	s.readyFired = true
+	fn := s.onReady
+	s.mu.Unlock()
+	fn(s.id)
+}
+
+// newSessionID returns a short, unique, URL-safe session identifier of the form
+// <unix-seconds>-<random-hex>.
+func newSessionID() string {
+	b := make([]byte, 4)
+	if _, err := rand.Read(b); err != nil {
+		// rand.Read essentially never fails; fall back to a time-only id.
+		return fmt.Sprintf("%d", time.Now().UnixNano())
+	}
+	return fmt.Sprintf("%d-%s", time.Now().Unix(), hex.EncodeToString(b))
+}

machinery/src/cloud/livesnapshot/publisher.go

@@ -0,0 +1,151 @@
+// Package livesnapshot implements the agent-side producer for the live-view
+// "preview" (SD) mode over HTTP.
+//
+// Historically the preview pipeline shipped each resized keyframe (a base64
+// JPEG, often chunked) to viewers over the MQTT broker. MQTT is a control plane
+// for small messages, so pushing ~1 image/second of base64 image data per
+// watched camera congests the broker and delays genuine control traffic. This
+// package moves those frames off MQTT: the agent POSTs the latest resized JPEG
+// straight to hub-api over plain HTTPS (outbound only), and viewers fetch it
+// back with their session token. Only the tiny "a viewer is watching" keepalive
+// stays on MQTT.
+//
+// The wire contract (agent -> hub-api) deliberately mirrors the live HLS ingest
+// and the existing storage-upload convention (X-Kerberos-Storage-Device plus the
+// Hub public/private key auth headers). hub-api authenticates the agent and
+// stores the frame in an ephemeral, short-TTL per-device slot which it serves
+// straight back to authorized viewers; the frame never enters the vault or the
+// recordings collection.
+//
+// Like live HLS segments, a preview frame is worthless once stale: a frame that
+// fails to upload is superseded by the next one a second later, so the publisher
+// is fire-and-forget and drops on failure (logged) rather than retrying.
+package livesnapshot
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"net/http"
+	"strings"
+	"time"
+
+	"github.com/kerberos-io/agent/machinery/src/log"
+)
+
+const (
+	// snapshotIngestPath is the hub-api endpoint that accepts the latest preview
+	// frame and stores it in the device's ephemeral snapshot slot (mirrors the
+	// /storage/live live-HLS ingest convention).
+	snapshotIngestPath = "/storage/snapshot"
+
+	contentTypeJPEG = "image/jpeg"
+
+	// Header names for the snapshot ingest contract (shared with live HLS / storage).
+	headerHubPublicKey  = "X-Kerberos-Hub-PublicKey"
+	headerHubPrivateKey = "X-Kerberos-Hub-PrivateKey"
+	headerHubRegion     = "X-Kerberos-Hub-Region"
+	headerStorageDevice = "X-Kerberos-Storage-Device"
+
+	// defaultPublishTimeout bounds a single snapshot upload. Preview frames are
+	// produced roughly once a second from a single goroutine, so an upload that
+	// cannot land in a few seconds is abandoned rather than allowed to back up the
+	// preview loop behind a slow request.
+	defaultPublishTimeout = 4 * time.Second
+)
+
+// PublisherConfig carries the hub endpoint and credentials needed to ship
+// preview frames. It is populated from the agent's models.Config (the same
+// HubURI/HubKey/HubPrivateKey used by recordings and live HLS).
+type PublisherConfig struct {
+	HubURI        string // base hub-api URL, e.g. https://api.hub.example.com
+	HubKey        string // Hub public key (X-Kerberos-Hub-PublicKey)
+	HubPrivateKey string // Hub private key (X-Kerberos-Hub-PrivateKey)
+	Region        string // storage region (X-Kerberos-Hub-Region), may be empty
+	DeviceKey     string // device/camera key (X-Kerberos-Storage-Device)
+
+	// Timeout optionally overrides defaultPublishTimeout (used by tests).
+	Timeout time.Duration
+	// HTTPClient optionally injects a client (used by tests). When nil a
+	// redirect-credential-stripping client is created.
+	HTTPClient *http.Client
+}
+
+// Publisher ships the latest preview frame to hub-api over plain HTTP POST.
+//
+// It is safe for sequential use from a single live-stream goroutine. PublishSnapshot
+// is fire-and-forget: it returns an error for the caller to log, but the caller is
+// expected to continue (drop-on-fail) rather than retry.
+type Publisher struct {
+	cfg    PublisherConfig
+	client *http.Client
+}
+
+// NewPublisher builds a Publisher. The HTTP client strips the Hub credential
+// headers on a cross-host redirect (net/http does this for standard auth headers
+// but not custom-named ones), matching the recording/live-HLS upload clients.
+func NewPublisher(cfg PublisherConfig) *Publisher {
+	client := cfg.HTTPClient
+	if client == nil {
+		timeout := cfg.Timeout
+		if timeout <= 0 {
+			timeout = defaultPublishTimeout
+		}
+		client = &http.Client{
+			Timeout:       timeout,
+			CheckRedirect: stripHubCredentialsOnCrossHostRedirect,
+		}
+	}
+	return &Publisher{cfg: cfg, client: client}
+}
+
+// PublishSnapshot uploads a single resized preview frame (JPEG) as the device's
+// latest snapshot. It overwrites whatever frame was there before, so viewers
+// always fetch the most recent frame.
+func (p *Publisher) PublishSnapshot(ctx context.Context, jpeg []byte) error {
+	if p.cfg.HubURI == "" {
+		return fmt.Errorf("livesnapshot: HubURI not configured")
+	}
+	if len(jpeg) == 0 {
+		return fmt.Errorf("livesnapshot: empty snapshot body")
+	}
+
+	url := strings.TrimRight(p.cfg.HubURI, "/") + snapshotIngestPath
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, bytes.NewReader(jpeg))
+	if err != nil {
+		return fmt.Errorf("livesnapshot: build request: %w", err)
+	}
+
+	req.Header.Set("Content-Type", contentTypeJPEG)
+	req.Header.Set(headerStorageDevice, p.cfg.DeviceKey)
+	req.Header.Set(headerHubPublicKey, p.cfg.HubKey)
+	req.Header.Set(headerHubPrivateKey, p.cfg.HubPrivateKey)
+	req.Header.Set(headerHubRegion, p.cfg.Region)
+
+	resp, err := p.client.Do(req)
+	if err != nil {
+		return fmt.Errorf("livesnapshot: upload snapshot: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		return fmt.Errorf("livesnapshot: upload snapshot rejected: %s", resp.Status)
+	}
+	log.Log.Debug("livesnapshot.Publisher.PublishSnapshot(): shipped preview frame for device " + p.cfg.DeviceKey)
+	return nil
+}
+
+// stripHubCredentialsOnCrossHostRedirect removes the Hub credential headers when
+// a redirect crosses to a different host. net/http strips standard sensitive
+// headers on a cross-host redirect but not custom-named ones, so without this the
+// Hub keys could leak to a redirect target.
+func stripHubCredentialsOnCrossHostRedirect(req *http.Request, via []*http.Request) error {
+	if len(via) == 0 {
+		return nil
+	}
+	if req.URL.Host != via[0].URL.Host {
+		req.Header.Del(headerHubPrivateKey)
+		req.Header.Del(headerHubPublicKey)
+	}
+	return nil
+}

machinery/src/cloud/tus_client.go

@@ -0,0 +1,546 @@
+package cloud
+
+import (
+	"encoding/base64"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"os"
+	"path/filepath"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/kerberos-io/agent/machinery/src/log"
+	"github.com/kerberos-io/agent/machinery/src/models"
+)
+
+// tusResumableVersion is the tus protocol version implemented by this client.
+const tusResumableVersion = "1.0.0"
+
+// tusUploadPath is appended to the configured Kerberos Vault URI to reach the
+// resumable upload endpoint. It mirrors how the legacy uploader appends
+// "/storage".
+const tusUploadPath = "/storage/tus/"
+
+// tusResumeState is persisted in a sidecar file next to the agent data so an
+// interrupted upload can be resumed across retries and even agent restarts.
+type tusResumeState struct {
+	UploadURL string `json:"upload_url"`
+	VaultURI  string `json:"vault_uri"`
+	Size      int64  `json:"size"`
+}
+
+// resumableUploadsEnabled reports whether the resumable (tus) upload path should
+// be attempted. It is enabled by default and can be disabled (falling back to
+// the legacy single POST) by setting AGENT_DISABLE_RESUMABLE_UPLOAD=true.
+func resumableUploadsEnabled() bool {
+	return os.Getenv("AGENT_DISABLE_RESUMABLE_UPLOAD") != "true"
+}
+
+// tusDefaultChunkSize is the number of bytes uploaded per PATCH request when no
+// explicit size is configured. Splitting the upload into chunks keeps each HTTP
+// request small enough for intermediary proxies/load balancers and checkpoints
+// progress frequently, so an interruption resumes with minimal re-upload.
+const tusDefaultChunkSize int64 = 8 << 20 // 8 MiB (>= S3 multipart minimum part size)
+
+const tusProgressBucketPercent int64 = 10
+
+// tusChunkSize returns the number of bytes to send per PATCH request. It
+// defaults to tusDefaultChunkSize (8 MiB) and can be overridden with the
+// AGENT_TUS_CHUNK_SIZE_BYTES environment variable. A value of 0 (or negative)
+// disables chunking and sends the remaining bytes in a single PATCH.
+func tusChunkSize() int64 {
+	v := os.Getenv("AGENT_TUS_CHUNK_SIZE_BYTES")
+	if v == "" {
+		return tusDefaultChunkSize
+	}
+	n, err := strconv.ParseInt(v, 10, 64)
+	if err != nil {
+		return tusDefaultChunkSize
+	}
+	if n <= 0 {
+		return 0 // chunking disabled: send everything in one PATCH
+	}
+	return n
+}
+
+func tusProgressBucket(offset, size int64) int64 {
+	if size <= 0 {
+		return 100
+	}
+	percent := (offset * 100) / size
+	if percent > 100 {
+		percent = 100
+	}
+	return percent / tusProgressBucketPercent
+}
+
+func logTusUploadProgress(label string, offset, size int64, loggedBucket *int64) {
+	bucket := tusProgressBucket(offset, size)
+	if bucket <= *loggedBucket {
+		return
+	}
+	*loggedBucket = bucket
+	percent := bucket * tusProgressBucketPercent
+	if percent > 100 {
+		percent = 100
+	}
+	log.Log.Infof("%s: resumable upload progress %d%% (%d/%d bytes)", label, percent, offset, size)
+}
+
+// tusHeaderFunc sets the authentication and routing headers required on every
+// tus request for a particular upload target (Kerberos Vault directly, or
+// Kerberos Hub which proxies to a vault). fileName is only meaningful on the
+// creation request; it is empty on HEAD/PATCH/DELETE.
+type tusHeaderFunc func(h http.Header, fileName string)
+
+// runTusUpload performs a resumable (tus) upload of data/recordings/<fileName>
+// to baseURL, sending target-specific authentication/routing headers via
+// setHeaders on every request. It encapsulates the create/resume/chunk/finalize
+// state machine shared by the Kerberos Vault (direct) and Kerberos Hub (proxied)
+// upload paths.
+//
+// Return values:
+//   - uploaded:  the recording was fully received and persisted by the server.
+//   - responded: the server returned a definitive HTTP response (used by the
+//     caller to advance its retry/secondary-failover policy).
+//   - supported: the server exposes a tus endpoint. When false, the caller
+//     should fall back to the legacy single-POST upload (older deployments).
+//   - body:      a short message for logging.
+func runTusUpload(baseURL, metadata, fileName, label, slot string, setHeaders tusHeaderFunc) (uploaded bool, responded bool, supported bool, body string, err error) {
+	fullname := "data/recordings/" + fileName
+
+	file, ferr := os.Open(fullname)
+	if file != nil {
+		defer file.Close()
+	}
+	if ferr != nil {
+		msg := label + ": resumable upload failed, file doesn't exist anymore"
+		log.Log.Info(msg)
+		// The file is gone, so the legacy path cannot help either. Report it as
+		// "supported" to avoid a pointless fallback attempt.
+		return false, false, true, "", errors.New(msg)
+	}
+
+	info, serr := file.Stat()
+	if serr != nil {
+		return false, false, true, "", serr
+	}
+	size := info.Size()
+
+	client := newVaultHTTPClient(0)
+	client.CheckRedirect = func(req *http.Request, via []*http.Request) error {
+		if len(via) == 0 {
+			return nil
+		}
+		if req.URL.Host != via[0].URL.Host {
+			for k := range req.Header {
+				if strings.HasPrefix(http.CanonicalHeaderKey(k), "X-Kerberos-") {
+					req.Header.Del(k)
+				}
+			}
+		}
+		return nil
+	}
+
+	sidecar := tusSidecarPath(fileName, slot)
+	uploadURL := loadTusResumeState(sidecar, baseURL)
+
+	const maxAttempts = 4
+	restartedAfterComplete := false
+
+	for attempt := 0; attempt < maxAttempts; attempt++ {
+		// (1) Ensure we have an active upload URL, creating one if needed.
+		if uploadURL == "" {
+			created, status, cerr := tusCreate(client, baseURL, size, metadata, setHeaders, fileName)
+			if cerr != nil {
+				if status == http.StatusNotFound || status == http.StatusMethodNotAllowed || status == http.StatusNotImplemented {
+					// The vault does not implement tus; let the caller fall back.
+					return false, false, false, "", cerr
+				}
+				log.Log.Info(label + ": resumable create failed, " + cerr.Error())
+				tusBackoff(attempt)
+				continue
+			}
+			uploadURL = created
+			saveTusResumeState(sidecar, tusResumeState{UploadURL: uploadURL, VaultURI: baseURL, Size: size})
+		}
+
+		// (2) Query the current server-side offset.
+		offset, status, herr := tusHead(client, uploadURL, setHeaders)
+		if herr != nil {
+			if status == http.StatusNotFound || status == http.StatusGone {
+				// The upload expired/was removed server-side; start over.
+				removeTusResumeState(sidecar)
+				uploadURL = ""
+				continue
+			}
+			log.Log.Info(label + ": resumable head failed, " + herr.Error())
+			tusBackoff(attempt)
+			continue
+		}
+
+		// (3) All bytes are present but the upload was not finalized (e.g. the
+		// completion hook failed). A completed tus upload cannot be re-finalized
+		// with another PATCH, so delete it and re-upload to force a clean finalize.
+		if offset >= size {
+			if restartedAfterComplete {
+				return false, true, true, "resumable finalize did not complete", errors.New(label + ": resumable finalize did not complete")
+			}
+			tusTerminate(client, uploadURL, setHeaders)
+			removeTusResumeState(sidecar)
+			uploadURL = ""
+			restartedAfterComplete = true
+			continue
+		}
+
+		// (4) Stream the remaining bytes to the vault via PATCH, reading directly
+		// from disk so the recording is never fully buffered in memory. When a chunk
+		// size is configured the data is sent across several PATCH requests,
+		// checkpointing the offset after each one so an interruption resumes from the
+		// last completed chunk instead of re-uploading everything.
+		chunkSize := tusChunkSize()
+		progressed := false
+		patchFailed := false
+		var lastBody string
+		loggedProgressBucket := tusProgressBucket(offset, size)
+		for offset < size {
+			// Re-seek every chunk so the on-disk position always matches the
+			// server-acknowledged offset, even if a PATCH was partially accepted.
+			if _, sErr := file.Seek(offset, io.SeekStart); sErr != nil {
+				return false, false, true, "", sErr
+			}
+			patchLen := size - offset
+			if chunkSize > 0 && chunkSize < patchLen {
+				patchLen = chunkSize
+			}
+			newOffset, status, respBody, perr := tusPatch(client, uploadURL, offset, patchLen, file, setHeaders)
+			if perr != nil {
+				if status >= 400 {
+					// Definitive rejection (e.g. provider push failed during finalize).
+					// Re-evaluate via HEAD on the next iteration to decide retry/restart.
+					log.Log.Info(label + ": resumable patch rejected, " + perr.Error())
+				} else {
+					log.Log.Info(label + ": resumable patch failed, " + perr.Error())
+				}
+				tusBackoff(attempt)
+				patchFailed = true
+				break
+			}
+			if newOffset > offset {
+				progressed = true
+			}
+			offset = newOffset
+			lastBody = respBody
+			logTusUploadProgress(label, offset, size, &loggedProgressBucket)
+			if offset < size {
+				// Partial progress: persist so a later retry resumes from here.
+				saveTusResumeState(sidecar, tusResumeState{UploadURL: uploadURL, VaultURI: baseURL, Size: size})
+			}
+		}
+		if patchFailed {
+			if progressed {
+				// Forward progress refreshes the retry budget: maxAttempts bounds the
+				// number of consecutive failures, not the number of chunks needed for
+				// a large recording.
+				attempt = -1
+			}
+			continue
+		}
+
+		// All declared bytes have been sent and acknowledged: the upload is done.
+		removeTusResumeState(sidecar)
+		return true, true, true, lastBody, nil
+	}
+
+	return false, true, true, "resumable upload did not complete after retries", errors.New(label + ": resumable upload did not complete after retries")
+}
+
+// uploadVaultResumable uploads a recording directly to a Kerberos Vault using
+// the tus resumable upload protocol. Credentials travel in the
+// X-Kerberos-Storage-* headers on every request and routing (directory/provider)
+// is additionally carried in the tus Upload-Metadata.
+func uploadVaultResumable(vault models.KStorage, publicKey, deviceKey, fileName, label, slot string) (bool, bool, bool, string, error) {
+	baseURL := strings.TrimRight(vault.URI, "/") + tusUploadPath
+	metadata := encodeTusMetadata(map[string]string{
+		"filename":  fileName,
+		"device":    deviceKey,
+		"directory": vault.Directory,
+		"provider":  vault.Provider,
+		"capture":   "IPCamera",
+		"cloudkey":  publicKey,
+	})
+	setHeaders := func(h http.Header, fn string) {
+		setVaultTusHeaders(h, vault, publicKey, deviceKey, fn)
+	}
+	return runTusUpload(baseURL, metadata, fileName, label, slot, setHeaders)
+}
+
+// uploadHubResumable uploads a recording to Kerberos Hub's tus endpoint, which
+// authenticates the agent with its Hub public/private key and proxies the
+// resumable upload to the Kerberos Vault on the agent's behalf. The vault
+// directory and provider are resolved and injected by Kerberos Hub, so they are
+// intentionally omitted from the metadata here.
+func uploadHubResumable(config *models.Config, fileName, label, slot string) (bool, bool, bool, string, error) {
+	baseURL := strings.TrimRight(config.HubURI, "/") + tusUploadPath
+	metadata := encodeTusMetadata(map[string]string{
+		"filename": fileName,
+		"device":   config.Key,
+		"capture":  "IPCamera",
+	})
+	setHeaders := func(h http.Header, fn string) {
+		setHubTusHeaders(h, config, fn)
+	}
+	return runTusUpload(baseURL, metadata, fileName, label, slot, setHeaders)
+}
+
+// tusCreate performs the tus "creation" request (POST). On success it returns
+// the resolved upload URL the agent should use for subsequent HEAD/PATCH calls.
+func tusCreate(client *http.Client, baseURL string, size int64, metadata string, setHeaders tusHeaderFunc, fileName string) (string, int, error) {
+	req, err := http.NewRequest("POST", baseURL, nil)
+	if err != nil {
+		return "", 0, err
+	}
+	req.Header.Set("Tus-Resumable", tusResumableVersion)
+	req.Header.Set("Upload-Length", strconv.FormatInt(size, 10))
+	if metadata != "" {
+		req.Header.Set("Upload-Metadata", metadata)
+	}
+	setHeaders(req.Header, fileName)
+
+	resp, err := client.Do(req)
+	if resp != nil {
+		defer resp.Body.Close()
+	}
+	if err != nil {
+		return "", 0, err
+	}
+	io.Copy(io.Discard, resp.Body)
+
+	if resp.StatusCode != http.StatusCreated {
+		return "", resp.StatusCode, fmt.Errorf("unexpected status creating upload: %s", resp.Status)
+	}
+	location := resp.Header.Get("Location")
+	if location == "" {
+		return "", resp.StatusCode, errors.New("missing Location header in create response")
+	}
+	return resolveTusLocation(baseURL, location), resp.StatusCode, nil
+}
+
+// tusHead performs the tus "offset" request (HEAD) and returns the current
+// server-side upload offset.
+func tusHead(client *http.Client, uploadURL string, setHeaders tusHeaderFunc) (int64, int, error) {
+	req, err := http.NewRequest("HEAD", uploadURL, nil)
+	if err != nil {
+		return 0, 0, err
+	}
+	req.Header.Set("Tus-Resumable", tusResumableVersion)
+	setHeaders(req.Header, "")
+
+	resp, err := client.Do(req)
+	if resp != nil {
+		defer resp.Body.Close()
+	}
+	if err != nil {
+		return 0, 0, err
+	}
+	io.Copy(io.Discard, resp.Body)
+
+	if resp.StatusCode != http.StatusOK && resp.StatusCode != http.StatusNoContent {
+		return 0, resp.StatusCode, fmt.Errorf("unexpected status on HEAD: %s", resp.Status)
+	}
+	offsetStr := resp.Header.Get("Upload-Offset")
+	offset, perr := strconv.ParseInt(offsetStr, 10, 64)
+	if perr != nil {
+		return 0, resp.StatusCode, fmt.Errorf("invalid Upload-Offset header: %q", offsetStr)
+	}
+	return offset, resp.StatusCode, nil
+}
+
+// tusPatch streams up to length bytes of the file (starting at offset) to the
+// upload URL using a single PATCH request. The body is read straight from the
+// *os.File, so the recording is never fully buffered in memory.
+func tusPatch(client *http.Client, uploadURL string, offset, length int64, file io.Reader, setHeaders tusHeaderFunc) (int64, int, string, error) {
+	req, err := http.NewRequest("PATCH", uploadURL, io.LimitReader(file, length))
+	if err != nil {
+		return offset, 0, "", err
+	}
+	req.ContentLength = length
+	req.Header.Set("Tus-Resumable", tusResumableVersion)
+	req.Header.Set("Content-Type", "application/offset+octet-stream")
+	req.Header.Set("Upload-Offset", strconv.FormatInt(offset, 10))
+	setHeaders(req.Header, "")
+
+	resp, err := client.Do(req)
+	if resp != nil {
+		defer resp.Body.Close()
+	}
+	if err != nil {
+		return offset, 0, "", err
+	}
+	bodyBytes, _ := io.ReadAll(resp.Body)
+	respBody := string(bodyBytes)
+
+	if resp.StatusCode != http.StatusNoContent {
+		return offset, resp.StatusCode, respBody, fmt.Errorf("unexpected status on PATCH: %s, %s", resp.Status, respBody)
+	}
+	newOffsetStr := resp.Header.Get("Upload-Offset")
+	newOffset, perr := strconv.ParseInt(newOffsetStr, 10, 64)
+	if perr != nil {
+		// A 204 without a parseable offset means this PATCH was fully accepted.
+		return offset + length, resp.StatusCode, respBody, nil
+	}
+	return newOffset, resp.StatusCode, respBody, nil
+}
+
+// tusTerminate best-effort deletes an upload server-side (DELETE).
+func tusTerminate(client *http.Client, uploadURL string, setHeaders tusHeaderFunc) {
+	req, err := http.NewRequest("DELETE", uploadURL, nil)
+	if err != nil {
+		return
+	}
+	req.Header.Set("Tus-Resumable", tusResumableVersion)
+	setHeaders(req.Header, "")
+
+	resp, derr := client.Do(req)
+	if resp != nil {
+		io.Copy(io.Discard, resp.Body)
+		resp.Body.Close()
+	}
+	_ = derr
+}
+
+// setVaultTusHeaders sets the Kerberos Vault authentication and routing headers
+// on every tus request. Credentials are sent on each request (and never stored
+// server-side in the upload metadata). When fileName is empty it is omitted, as
+// it is only useful on the creation request (routing also travels in the tus
+// Upload-Metadata).
+func setVaultTusHeaders(h http.Header, vault models.KStorage, publicKey, deviceKey, fileName string) {
+	h.Set("X-Kerberos-Storage-CloudKey", publicKey)
+	h.Set("X-Kerberos-Storage-AccessKey", vault.AccessKey)
+	h.Set("X-Kerberos-Storage-SecretAccessKey", vault.SecretAccessKey)
+	h.Set("X-Kerberos-Storage-Provider", vault.Provider)
+	h.Set("X-Kerberos-Storage-Device", deviceKey)
+	h.Set("X-Kerberos-Storage-Directory", vault.Directory)
+	h.Set("X-Kerberos-Storage-Capture", "IPCamera")
+	if fileName != "" {
+		h.Set("X-Kerberos-Storage-FileName", fileName)
+	}
+}
+
+// setHubTusHeaders sets the Kerberos Hub authentication headers on every tus
+// request of a hub-proxied resumable upload. The agent authenticates with its
+// Hub public/private key (exactly as the legacy single-POST hub upload does);
+// Kerberos Hub validates the subscription and injects the vault credentials and
+// directory/provider on the agent's behalf.
+func setHubTusHeaders(h http.Header, config *models.Config, fileName string) {
+	h.Set("X-Kerberos-Hub-PublicKey", config.HubKey)
+	h.Set("X-Kerberos-Hub-PrivateKey", config.HubPrivateKey)
+	h.Set("X-Kerberos-Hub-Region", config.S3.Region)
+	h.Set("X-Kerberos-Storage-Device", config.Key)
+	h.Set("X-Kerberos-Storage-Capture", "IPCamera")
+	if fileName != "" {
+		h.Set("X-Kerberos-Storage-FileName", fileName)
+	}
+}
+
+// encodeTusMetadata serializes a map into the tus Upload-Metadata header format:
+// a comma separated list of "key base64(value)" pairs. Keys are sorted for a
+// deterministic header value. Empty values are skipped.
+func encodeTusMetadata(pairs map[string]string) string {
+	parts := make([]string, 0, len(pairs))
+	for k, v := range pairs {
+		if v == "" {
+			continue
+		}
+		parts = append(parts, k+" "+base64.StdEncoding.EncodeToString([]byte(v)))
+	}
+	sort.Strings(parts)
+	return strings.Join(parts, ",")
+}
+
+// resolveTusLocation turns the Location header returned by the create request
+// into an absolute URL. To keep talking to the agent's configured vault host
+// (and avoid issues when the vault sits behind a proxy that rewrites the host),
+// it keeps the configured base URL and only appends the server-assigned upload
+// id taken from the Location.
+func resolveTusLocation(baseURL, location string) string {
+	if ref, err := url.Parse(location); err == nil {
+		trimmed := strings.Trim(ref.Path, "/")
+		if trimmed != "" {
+			segments := strings.Split(trimmed, "/")
+			id := segments[len(segments)-1]
+			if id != "" {
+				return strings.TrimRight(baseURL, "/") + "/" + id
+			}
+		}
+	}
+	// Fallback: resolve the reference against the base URL as-is.
+	if base, err := url.Parse(baseURL); err == nil {
+		if ref, err := url.Parse(location); err == nil {
+			return base.ResolveReference(ref).String()
+		}
+	}
+	return location
+}
+
+// tusSidecarDir is the directory where resume state files are kept. It is
+// intentionally separate from data/cloud (which is scanned for recordings to
+// upload) so the sidecar files are never mistaken for recordings.
+func tusSidecarDir() string {
+	return "data/tus"
+}
+
+func tusSidecarPath(fileName, slot string) string {
+	safe := strings.ReplaceAll(fileName, "/", "_")
+	safe = strings.ReplaceAll(safe, string(os.PathSeparator), "_")
+	return filepath.Join(tusSidecarDir(), safe+"."+slot+".json")
+}
+
+// loadTusResumeState returns a previously stored upload URL for the given
+// sidecar, but only if it was created against the same vault base URL. Any
+// mismatch or read/parse error yields an empty string (start fresh).
+func loadTusResumeState(path, baseURL string) string {
+	b, err := os.ReadFile(path)
+	if err != nil {
+		return ""
+	}
+	var state tusResumeState
+	if err := json.Unmarshal(b, &state); err != nil {
+		return ""
+	}
+	if state.UploadURL == "" || state.VaultURI != baseURL {
+		return ""
+	}
+	return state.UploadURL
+}
+
+func saveTusResumeState(path string, state tusResumeState) {
+	if err := os.MkdirAll(filepath.Dir(path), 0o755); err != nil {
+		return
+	}
+	b, err := json.Marshal(state)
+	if err != nil {
+		return
+	}
+	_ = os.WriteFile(path, b, 0o644)
+}
+
+func removeTusResumeState(path string) {
+	_ = os.Remove(path)
+}
+
+// tusBackoff sleeps for an exponentially increasing duration (capped) between
+// resume attempts to avoid hammering a temporarily unavailable vault.
+func tusBackoff(attempt int) {
+	delay := time.Duration(500*(1<<uint(attempt))) * time.Millisecond
+	if delay > 3*time.Second {
+		delay = 3 * time.Second
+	}
+	time.Sleep(delay)
+}

machinery/src/cloud/tus_client_test.go

@@ -0,0 +1,608 @@
+package cloud
+
+import (
+	"bytes"
+	"encoding/base64"
+	"fmt"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"sync"
+	"testing"
+
+	"github.com/kerberos-io/agent/machinery/src/models"
+)
+
+// fakeUpload tracks the state of a single resumable upload on the fake server.
+type fakeUpload struct {
+	size   int64
+	offset int64
+}
+
+// recordedRequest captures the method and headers of a request received by the
+// fake tus server, so tests can assert the client's per-method auth headers.
+type recordedRequest struct {
+	method string
+	header http.Header
+}
+
+// fakeTus is a tiny in-memory implementation of the tus 1.0.0 server protocol,
+// sufficient to exercise the agent's resumable client.
+type fakeTus struct {
+	mu             sync.Mutex
+	uploads        map[string]*fakeUpload
+	counter        int
+	creates        int
+	lastPatchBytes int64
+	patchSizes     []int64
+
+	// unsupported makes the creation endpoint return 404, simulating an older
+	// vault without a tus endpoint.
+	unsupported bool
+	// failFinalize causes the next N completing PATCH requests to return 502
+	// after storing the bytes, simulating a failed completion hook.
+	failFinalize int
+
+	// requests records the headers of every received request (in order) so
+	// tests can assert which auth/routing headers the client sent per method.
+	requests []recordedRequest
+}
+
+func newFakeTus() *fakeTus {
+	return &fakeTus{uploads: map[string]*fakeUpload{}}
+}
+
+func (s *fakeTus) seed(size, offset int64) string {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.counter++
+	id := fmt.Sprintf("seed-%d", s.counter)
+	s.uploads[id] = &fakeUpload{size: size, offset: offset}
+	return id
+}
+
+func (s *fakeTus) totalBytes() int64 {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	var total int64
+	for _, u := range s.uploads {
+		total += u.offset
+	}
+	return total
+}
+
+func (s *fakeTus) lastPatch() int64 {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.lastPatchBytes
+}
+
+// patchCounts returns the number of PATCH requests received and the size of each.
+func (s *fakeTus) patchCounts() (int, []int64) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	sizes := make([]int64, len(s.patchSizes))
+	copy(sizes, s.patchSizes)
+	return len(s.patchSizes), sizes
+}
+
+func (s *fakeTus) createCount() int {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.creates
+}
+
+// requestsForMethod returns the recorded requests for the given HTTP method.
+func (s *fakeTus) requestsForMethod(method string) []recordedRequest {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	var out []recordedRequest
+	for _, req := range s.requests {
+		if req.method == method {
+			out = append(out, req)
+		}
+	}
+	return out
+}
+
+func (s *fakeTus) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	id := strings.TrimPrefix(r.URL.Path, tusUploadPath)
+	w.Header().Set("Tus-Resumable", tusResumableVersion)
+
+	s.mu.Lock()
+	s.requests = append(s.requests, recordedRequest{method: r.Method, header: r.Header.Clone()})
+	s.mu.Unlock()
+
+	switch r.Method {
+	case http.MethodPost:
+		if s.unsupported {
+			w.WriteHeader(http.StatusNotFound)
+			return
+		}
+		length, _ := strconv.ParseInt(r.Header.Get("Upload-Length"), 10, 64)
+		s.mu.Lock()
+		s.counter++
+		s.creates++
+		newID := fmt.Sprintf("up-%d", s.counter)
+		s.uploads[newID] = &fakeUpload{size: length}
+		s.mu.Unlock()
+		w.Header().Set("Location", tusUploadPath+newID)
+		w.WriteHeader(http.StatusCreated)
+
+	case http.MethodHead:
+		s.mu.Lock()
+		u, ok := s.uploads[id]
+		s.mu.Unlock()
+		if !ok {
+			w.WriteHeader(http.StatusNotFound)
+			return
+		}
+		w.Header().Set("Upload-Offset", strconv.FormatInt(u.offset, 10))
+		w.Header().Set("Upload-Length", strconv.FormatInt(u.size, 10))
+		w.WriteHeader(http.StatusOK)
+
+	case http.MethodPatch:
+		s.mu.Lock()
+		u, ok := s.uploads[id]
+		s.mu.Unlock()
+		if !ok {
+			w.WriteHeader(http.StatusNotFound)
+			return
+		}
+		n, _ := io.Copy(io.Discard, r.Body)
+		s.mu.Lock()
+		u.offset += n
+		s.lastPatchBytes = n
+		s.patchSizes = append(s.patchSizes, n)
+		complete := u.offset >= u.size
+		failNow := complete && s.failFinalize > 0
+		if failNow {
+			s.failFinalize--
+		}
+		offset := u.offset
+		s.mu.Unlock()
+
+		w.Header().Set("Upload-Offset", strconv.FormatInt(offset, 10))
+		if failNow {
+			// Bytes are stored but the (simulated) completion hook failed.
+			w.WriteHeader(http.StatusBadGateway)
+			return
+		}
+		w.WriteHeader(http.StatusNoContent)
+
+	case http.MethodDelete:
+		s.mu.Lock()
+		delete(s.uploads, id)
+		s.mu.Unlock()
+		w.WriteHeader(http.StatusNoContent)
+
+	default:
+		w.WriteHeader(http.StatusMethodNotAllowed)
+	}
+}
+
+// withRecording switches into a fresh temp working directory containing a
+// recording at data/recordings/<fileName>. The working directory is restored on
+// cleanup. Tests using this helper must not run in parallel.
+func withRecording(t *testing.T, fileName string, payload []byte) {
+	t.Helper()
+	dir := t.TempDir()
+	old, err := os.Getwd()
+	if err != nil {
+		t.Fatalf("getwd: %v", err)
+	}
+	if err := os.Chdir(dir); err != nil {
+		t.Fatalf("chdir: %v", err)
+	}
+	t.Cleanup(func() { _ = os.Chdir(old) })
+
+	if err := os.MkdirAll("data/recordings", 0o755); err != nil {
+		t.Fatalf("mkdir recordings: %v", err)
+	}
+	if err := os.WriteFile(filepath.Join("data/recordings", fileName), payload, 0o644); err != nil {
+		t.Fatalf("write recording: %v", err)
+	}
+}
+
+func testVault(uri string) models.KStorage {
+	return models.KStorage{
+		URI:             uri,
+		AccessKey:       "ak",
+		SecretAccessKey: "sk",
+		Provider:        "gcp",
+		Directory:       "dir",
+	}
+}
+
+func TestUploadVaultResumable_HappyPath(t *testing.T) {
+	srv := newFakeTus()
+	ts := httptest.NewServer(srv)
+	defer ts.Close()
+
+	fileName := "1564859471_6-474162_oprit_577-283-727-375_1153_27.mp4"
+	payload := bytes.Repeat([]byte("x"), 4096)
+	withRecording(t, fileName, payload)
+
+	uploaded, responded, supported, _, err := uploadVaultResumable(testVault(ts.URL), "pk", "dev", fileName, "test", "primary")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if !uploaded || !responded || !supported {
+		t.Fatalf("uploaded/responded/supported = %v/%v/%v, want all true", uploaded, responded, supported)
+	}
+	if got := srv.totalBytes(); got != int64(len(payload)) {
+		t.Fatalf("server received %d bytes, want %d", got, len(payload))
+	}
+	if _, err := os.Stat(tusSidecarPath(fileName, "primary")); !os.IsNotExist(err) {
+		t.Fatalf("expected sidecar to be removed after success, stat err = %v", err)
+	}
+}
+
+func TestUploadVaultResumable_Chunked(t *testing.T) {
+	srv := newFakeTus()
+	ts := httptest.NewServer(srv)
+	defer ts.Close()
+
+	fileName := "1564859471_6-474162_oprit_577-283-727-375_1153_27.mp4"
+	// 10 KiB payload uploaded in 4 KiB chunks => 3 PATCH requests (4096+4096+2048).
+	payload := bytes.Repeat([]byte("c"), 10240)
+	withRecording(t, fileName, payload)
+	t.Setenv("AGENT_TUS_CHUNK_SIZE_BYTES", "4096")
+
+	uploaded, _, supported, _, err := uploadVaultResumable(testVault(ts.URL), "pk", "dev", fileName, "test", "primary")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if !uploaded || !supported {
+		t.Fatalf("expected chunked upload success, got uploaded=%v supported=%v", uploaded, supported)
+	}
+	if got := srv.totalBytes(); got != int64(len(payload)) {
+		t.Fatalf("server received %d bytes, want %d", got, len(payload))
+	}
+	count, sizes := srv.patchCounts()
+	if count != 3 {
+		t.Fatalf("expected 3 chunked PATCH requests, got %d (sizes=%v)", count, sizes)
+	}
+	want := []int64{4096, 4096, 2048}
+	for i, w := range want {
+		if sizes[i] != w {
+			t.Fatalf("chunk %d size = %d, want %d (sizes=%v)", i, sizes[i], w, sizes)
+		}
+	}
+	if _, err := os.Stat(tusSidecarPath(fileName, "primary")); !os.IsNotExist(err) {
+		t.Fatalf("expected sidecar removed after success, stat err = %v", err)
+	}
+}
+
+func TestUploadVaultResumable_ChunkingDisabled(t *testing.T) {
+	srv := newFakeTus()
+	ts := httptest.NewServer(srv)
+	defer ts.Close()
+
+	fileName := "1564859471_6-474162_oprit_577-283-727-375_1153_27.mp4"
+	payload := bytes.Repeat([]byte("d"), 10240)
+	withRecording(t, fileName, payload)
+	// 0 disables chunking: the whole file should go out in a single PATCH.
+	t.Setenv("AGENT_TUS_CHUNK_SIZE_BYTES", "0")
+
+	uploaded, _, supported, _, err := uploadVaultResumable(testVault(ts.URL), "pk", "dev", fileName, "test", "primary")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if !uploaded || !supported {
+		t.Fatalf("expected success, got uploaded=%v supported=%v", uploaded, supported)
+	}
+	count, sizes := srv.patchCounts()
+	if count != 1 {
+		t.Fatalf("expected a single PATCH when chunking is disabled, got %d (sizes=%v)", count, sizes)
+	}
+	if sizes[0] != int64(len(payload)) {
+		t.Fatalf("single PATCH size = %d, want %d", sizes[0], len(payload))
+	}
+}
+
+func TestTusChunkSize(t *testing.T) {
+	cases := []struct {
+		name string
+		env  string
+		set  bool
+		want int64
+	}{
+		{name: "default when unset", set: false, want: tusDefaultChunkSize},
+		{name: "default on invalid", env: "notanumber", set: true, want: tusDefaultChunkSize},
+		{name: "explicit value", env: "65536", set: true, want: 65536},
+		{name: "zero disables", env: "0", set: true, want: 0},
+		{name: "negative disables", env: "-5", set: true, want: 0},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			if tc.set {
+				t.Setenv("AGENT_TUS_CHUNK_SIZE_BYTES", tc.env)
+			} else {
+				t.Setenv("AGENT_TUS_CHUNK_SIZE_BYTES", "")
+			}
+			if got := tusChunkSize(); got != tc.want {
+				t.Fatalf("tusChunkSize() = %d, want %d", got, tc.want)
+			}
+		})
+	}
+}
+
+func TestUploadVaultResumable_Unsupported(t *testing.T) {
+	srv := newFakeTus()
+	srv.unsupported = true
+	ts := httptest.NewServer(srv)
+	defer ts.Close()
+
+	fileName := "f.mp4"
+	withRecording(t, fileName, []byte("hello"))
+
+	uploaded, _, supported, _, _ := uploadVaultResumable(testVault(ts.URL), "pk", "dev", fileName, "test", "primary")
+	if uploaded {
+		t.Fatal("expected uploaded=false against a vault without a tus endpoint")
+	}
+	if supported {
+		t.Fatal("expected supported=false so the caller falls back to the legacy upload")
+	}
+}
+
+func TestUploadVaultResumable_FinalizeRetry(t *testing.T) {
+	srv := newFakeTus()
+	srv.failFinalize = 1
+	ts := httptest.NewServer(srv)
+	defer ts.Close()
+
+	fileName := "1564859471_6-474162_oprit_577-283-727-375_1153_27.mp4"
+	payload := bytes.Repeat([]byte("y"), 2048)
+	withRecording(t, fileName, payload)
+
+	uploaded, _, supported, _, err := uploadVaultResumable(testVault(ts.URL), "pk", "dev", fileName, "test", "primary")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if !uploaded || !supported {
+		t.Fatalf("expected success after a failed finalize + restart, got uploaded=%v supported=%v", uploaded, supported)
+	}
+	if got := srv.createCount(); got < 2 {
+		t.Fatalf("expected at least 2 create requests (restart after failed finalize), got %d", got)
+	}
+}
+
+func TestUploadVaultResumable_ResumeFromSidecar(t *testing.T) {
+	srv := newFakeTus()
+	ts := httptest.NewServer(srv)
+	defer ts.Close()
+
+	fileName := "1564859471_6-474162_oprit_577-283-727-375_1153_27.mp4"
+	total := 8192
+	half := 4096
+	payload := bytes.Repeat([]byte("z"), total)
+	withRecording(t, fileName, payload)
+
+	// Simulate a previous run that uploaded half the file before being interrupted.
+	id := srv.seed(int64(total), int64(half))
+	baseURL := strings.TrimRight(ts.URL, "/") + tusUploadPath
+	saveTusResumeState(tusSidecarPath(fileName, "primary"), tusResumeState{
+		UploadURL: strings.TrimRight(baseURL, "/") + "/" + id,
+		VaultURI:  baseURL,
+		Size:      int64(total),
+	})
+
+	uploaded, _, supported, _, err := uploadVaultResumable(testVault(ts.URL), "pk", "dev", fileName, "test", "primary")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if !uploaded || !supported {
+		t.Fatalf("expected resume success, got uploaded=%v supported=%v", uploaded, supported)
+	}
+	if got := srv.lastPatch(); got != int64(total-half) {
+		t.Fatalf("resume should only send the remaining %d bytes, sent %d", total-half, got)
+	}
+	if srv.createCount() != 0 {
+		t.Fatalf("resume should not create a new upload, got %d creates", srv.createCount())
+	}
+}
+
+func testHubConfig(hubURI string) *models.Config {
+	return &models.Config{
+		Key:           "device-key",
+		HubURI:        hubURI,
+		HubKey:        "hubpub",
+		HubPrivateKey: "hubpriv",
+		S3:            &models.S3{Region: "eu-west"},
+	}
+}
+
+// decodeTusMetadata parses a tus Upload-Metadata header value ("key b64,key b64")
+// back into a map of decoded key/value pairs.
+func decodeTusMetadata(meta string) map[string]string {
+	out := map[string]string{}
+	if meta == "" {
+		return out
+	}
+	for _, pair := range strings.Split(meta, ",") {
+		parts := strings.SplitN(strings.TrimSpace(pair), " ", 2)
+		if parts[0] == "" {
+			continue
+		}
+		val := ""
+		if len(parts) == 2 {
+			if b, err := base64.StdEncoding.DecodeString(parts[1]); err == nil {
+				val = string(b)
+			}
+		}
+		out[parts[0]] = val
+	}
+	return out
+}
+
+func TestUploadHubResumable_HappyPath(t *testing.T) {
+	srv := newFakeTus()
+	ts := httptest.NewServer(srv)
+	defer ts.Close()
+
+	fileName := "1564859471_6-474162_oprit_577-283-727-375_1153_27.mp4"
+	payload := bytes.Repeat([]byte("h"), 4096)
+	withRecording(t, fileName, payload)
+
+	uploaded, _, supported, _, err := uploadHubResumable(testHubConfig(ts.URL), fileName, "test", "hub")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if !uploaded || !supported {
+		t.Fatalf("uploaded/supported = %v/%v, want both true", uploaded, supported)
+	}
+	if got := srv.totalBytes(); got != int64(len(payload)) {
+		t.Fatalf("server received %d bytes, want %d", got, len(payload))
+	}
+
+	// The Hub auth headers must be present on every request type (POST/HEAD/PATCH),
+	// because Kerberos Hub validates them on each proxied request. Conversely the
+	// vault credentials/routing are injected by Kerberos Hub on the agent's behalf
+	// and must never be sent by the agent on the hub path.
+	for _, method := range []string{http.MethodPost, http.MethodHead, http.MethodPatch} {
+		reqs := srv.requestsForMethod(method)
+		if len(reqs) == 0 {
+			t.Fatalf("expected at least one %s request", method)
+		}
+		for _, req := range reqs {
+			if got := req.header.Get("X-Kerberos-Hub-PublicKey"); got != "hubpub" {
+				t.Errorf("%s: X-Kerberos-Hub-PublicKey = %q, want %q", method, got, "hubpub")
+			}
+			if got := req.header.Get("X-Kerberos-Hub-PrivateKey"); got != "hubpriv" {
+				t.Errorf("%s: X-Kerberos-Hub-PrivateKey = %q, want %q", method, got, "hubpriv")
+			}
+			if got := req.header.Get("X-Kerberos-Hub-Region"); got != "eu-west" {
+				t.Errorf("%s: X-Kerberos-Hub-Region = %q, want %q", method, got, "eu-west")
+			}
+			if got := req.header.Get("X-Kerberos-Storage-Device"); got != "device-key" {
+				t.Errorf("%s: X-Kerberos-Storage-Device = %q, want %q", method, got, "device-key")
+			}
+			for _, h := range []string{
+				"X-Kerberos-Storage-AccessKey",
+				"X-Kerberos-Storage-SecretAccessKey",
+				"X-Kerberos-Storage-CloudKey",
+				"X-Kerberos-Storage-Provider",
+				"X-Kerberos-Storage-Directory",
+			} {
+				if got := req.header.Get(h); got != "" {
+					t.Errorf("%s: %s should be empty on the hub path, got %q", method, h, got)
+				}
+			}
+		}
+	}
+
+	// The creation request carries the upload metadata; on the hub path it must
+	// omit directory/provider/cloudkey (Hub resolves those) but include
+	// filename/device/capture. The filename header is also set on create.
+	posts := srv.requestsForMethod(http.MethodPost)
+	if got := posts[0].header.Get("X-Kerberos-Storage-FileName"); got != fileName {
+		t.Errorf("POST X-Kerberos-Storage-FileName = %q, want %q", got, fileName)
+	}
+	meta := decodeTusMetadata(posts[0].header.Get("Upload-Metadata"))
+	for _, omitted := range []string{"directory", "provider", "cloudkey"} {
+		if _, ok := meta[omitted]; ok {
+			t.Errorf("hub metadata must omit %q, got %v", omitted, meta)
+		}
+	}
+	if meta["filename"] != fileName {
+		t.Errorf("hub metadata filename = %q, want %q", meta["filename"], fileName)
+	}
+	if meta["device"] != "device-key" {
+		t.Errorf("hub metadata device = %q, want %q", meta["device"], "device-key")
+	}
+	if meta["capture"] != "IPCamera" {
+		t.Errorf("hub metadata capture = %q, want %q", meta["capture"], "IPCamera")
+	}
+}
+
+func TestUploadHubResumable_Unsupported(t *testing.T) {
+	srv := newFakeTus()
+	srv.unsupported = true
+	ts := httptest.NewServer(srv)
+	defer ts.Close()
+
+	fileName := "f.mp4"
+	withRecording(t, fileName, []byte("hello"))
+
+	uploaded, _, supported, _, _ := uploadHubResumable(testHubConfig(ts.URL), fileName, "test", "hub")
+	if uploaded {
+		t.Fatal("expected uploaded=false against a hub without a tus endpoint")
+	}
+	if supported {
+		t.Fatal("expected supported=false so the caller falls back to the legacy upload")
+	}
+}
+
+func TestEncodeTusMetadata(t *testing.T) {
+	got := encodeTusMetadata(map[string]string{
+		"b":     "2",
+		"a":     "1",
+		"empty": "",
+	})
+	// keys sorted, empty values skipped, values base64-encoded.
+	want := "a MQ==,b Mg=="
+	if got != want {
+		t.Fatalf("encodeTusMetadata = %q, want %q", got, want)
+	}
+}
+
+func TestResolveTusLocation(t *testing.T) {
+	cases := []struct {
+		name     string
+		base     string
+		location string
+		want     string
+	}{
+		{
+			name:     "absolute path location",
+			base:     "http://host/storage/tus/",
+			location: "/storage/tus/abc",
+			want:     "http://host/storage/tus/abc",
+		},
+		{
+			name:     "absolute url keeps configured host",
+			base:     "http://host/storage/tus/",
+			location: "http://internal:8080/storage/tus/xyz",
+			want:     "http://host/storage/tus/xyz",
+		},
+		{
+			name:     "relative id",
+			base:     "http://host/api/storage/tus/",
+			location: "abc",
+			want:     "http://host/api/storage/tus/abc",
+		},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			if got := resolveTusLocation(tc.base, tc.location); got != tc.want {
+				t.Fatalf("resolveTusLocation(%q, %q) = %q, want %q", tc.base, tc.location, got, tc.want)
+			}
+		})
+	}
+}
+
+func TestTusResumeStateRoundTrip(t *testing.T) {
+	dir := t.TempDir()
+	old, _ := os.Getwd()
+	if err := os.Chdir(dir); err != nil {
+		t.Fatalf("chdir: %v", err)
+	}
+	defer os.Chdir(old)
+
+	path := tusSidecarPath("file.mp4", "primary")
+	state := tusResumeState{UploadURL: "http://host/storage/tus/abc", VaultURI: "http://host/storage/tus/", Size: 123}
+	saveTusResumeState(path, state)
+
+	if got := loadTusResumeState(path, state.VaultURI); got != state.UploadURL {
+		t.Fatalf("loadTusResumeState = %q, want %q", got, state.UploadURL)
+	}
+	// A mismatched vault URI must not be reused.
+	if got := loadTusResumeState(path, "http://other/storage/tus/"); got != "" {
+		t.Fatalf("loadTusResumeState with mismatched vault = %q, want empty", got)
+	}
+}

machinery/src/components/kerberos.go

@@ -2,6 +2,7 @@ package components
 
 import (
 	"context"
+	"fmt"
 	"os"
 	"strconv"
 	"sync/atomic"
@@ -69,8 +70,10 @@ func Bootstrap(ctx context.Context, configDirectory string, configuration *model
 	communication.HandleUpload = make(chan string, 1)
 	communication.HandleHeartBeat = make(chan string, 1)
 	communication.HandleLiveSD = make(chan int64, 1)
+	communication.HandleLiveSDHTTP = make(chan int64, 1)
 	communication.HandleLiveHDKeepalive = make(chan string, 1)
 	communication.HandleLiveHDPeers = make(chan string, 1)
+	communication.HandleLiveHLS = make(chan int64, 1)
 	communication.IsConfiguring = abool.New()
 
 	cameraSettings := &models.Camera{}
@@ -175,19 +178,10 @@ func RunAgent(configDirectory string, configuration *models.Configuration, commu
 	configuration.Config.Capture.IPCamera.Height = height
 
 	// Set the liveview width and height, this is used for the liveview and motion regions (drawing on the hub).
-	baseWidth := config.Capture.IPCamera.BaseWidth
-	baseHeight := config.Capture.IPCamera.BaseHeight
-	// If the liveview height is not set, we will calculate it based on the width and aspect ratio of the camera.
-	if baseWidth > 0 && baseHeight == 0 {
-		widthAspectRatio := float64(baseWidth) / float64(width)
-		configuration.Config.Capture.IPCamera.BaseHeight = int(float64(height) * widthAspectRatio)
-	} else if baseHeight > 0 && baseWidth > 0 {
-		configuration.Config.Capture.IPCamera.BaseHeight = baseHeight
-		configuration.Config.Capture.IPCamera.BaseWidth = baseWidth
-	} else {
-		configuration.Config.Capture.IPCamera.BaseHeight = height
-		configuration.Config.Capture.IPCamera.BaseWidth = width
-	}
+	// ResolveBaseDimensions gates the aspect-ratio compute on width/height > 0
+	// so a not-yet-probed stream can't poison the dimensions and crash resize.
+	configuration.Config.Capture.IPCamera.BaseWidth, configuration.Config.Capture.IPCamera.BaseHeight =
+		utils.ResolveBaseDimensions(config.Capture.IPCamera.BaseWidth, config.Capture.IPCamera.BaseHeight, width, height)
 
 	// Set the SPS and PPS values in the configuration.
 	configuration.Config.Capture.IPCamera.SPSNALUs = [][]byte{videoStream.SPS}
@@ -245,19 +239,8 @@ func RunAgent(configDirectory string, configuration *models.Configuration, commu
 
 		// If we have a substream, we need to set the width and height of the substream. (so we will override above information)
 		// Set the liveview width and height, this is used for the liveview and motion regions (drawing on the hub).
-		baseWidth := config.Capture.IPCamera.BaseWidth
-		baseHeight := config.Capture.IPCamera.BaseHeight
-		// If the liveview height is not set, we will calculate it based on the width and aspect ratio of the camera.
-		if baseWidth > 0 && baseHeight == 0 {
-			widthAspectRatio := float64(baseWidth) / float64(width)
-			configuration.Config.Capture.IPCamera.BaseHeight = int(float64(height) * widthAspectRatio)
-		} else if baseHeight > 0 && baseWidth > 0 {
-			configuration.Config.Capture.IPCamera.BaseHeight = baseHeight
-			configuration.Config.Capture.IPCamera.BaseWidth = baseWidth
-		} else {
-			configuration.Config.Capture.IPCamera.BaseHeight = height
-			configuration.Config.Capture.IPCamera.BaseWidth = width
-		}
+		configuration.Config.Capture.IPCamera.BaseWidth, configuration.Config.Capture.IPCamera.BaseHeight =
+			utils.ResolveBaseDimensions(config.Capture.IPCamera.BaseWidth, config.Capture.IPCamera.BaseHeight, width, height)
 	}
 
 	// We are creating a queue to store the RTSP frames in, these frames will be
@@ -303,6 +286,18 @@ func RunAgent(configDirectory string, configuration *models.Configuration, commu
 		go cloud.HandleLiveStreamSD(livestreamCursor, configuration, communication, mqttClient, rtspClient)
 	}
 
+	// Handle livestream HLS (adaptive segments over HTTP via hub-api -> vault).
+	// Uses the sub stream when available (lower bitrate, browser-friendly), else
+	// the main stream. Like SD it is viewer-keepalive gated and produces no
+	// traffic while nobody is watching.
+	if subStreamEnabled {
+		livestreamHLSCursor := subQueue.Latest()
+		go cloud.HandleLiveStreamHLS(livestreamHLSCursor, configuration, communication, mqttClient, rtspSubClient)
+	} else {
+		livestreamHLSCursor := queue.Latest()
+		go cloud.HandleLiveStreamHLS(livestreamHLSCursor, configuration, communication, mqttClient, rtspClient)
+	}
+
 	// Handle livestream HD (high resolution over WEBRTC)
 	communication.HandleLiveHDHandshake = make(chan models.LiveHDHandshake, 100)
 	if subStreamEnabled {
@@ -446,6 +441,37 @@ func RunAgent(configDirectory string, configuration *models.Configuration, commu
 	return status
 }
 
+// packetAgeString returns a human readable age (e.g. "12s") since the last
+// packet timestamp stored in the given atomic.Value, or "unknown" when no
+// packet has been received yet. Used to add context to watchdog restart logs.
+func packetAgeString(timer *atomic.Value) string {
+	if timer == nil {
+		return "unknown"
+	}
+
+	// atomic.Value panics on Load() if it was never initialized via Store().
+	var v any
+	func() {
+		defer func() {
+			if recover() != nil {
+				v = nil
+			}
+		}()
+		v = timer.Load()
+	}()
+
+	last, ok := v.(int64)
+	if !ok || last == 0 {
+		return "unknown"
+	}
+
+	age := time.Now().Unix() - last
+	if age < 0 {
+		age = 0
+	}
+	return strconv.FormatInt(age, 10) + "s"
+}
+
 // ControlAgent will check if the camera is still connected, if not it will restart the agent.
 // In the other thread we are keeping track of the number of packets received, and particular the keyframe packets.
 // Once we are not receiving any packets anymore, we will restart the agent.
@@ -480,7 +506,8 @@ func ControlAgent(communication *models.Communication) {
 
 				// After 15 seconds without activity this is thrown..
 				if occurence == 3 {
-					log.Log.Info("components.Kerberos.ControlAgent(): Restarting machinery because of blocking mainstream.")
+					log.Log.Info(fmt.Sprintf("components.Kerberos.ControlAgent(): Restarting machinery because of blocking mainstream. (stalledKeyframeCounter=%d, lastPacket=%s ago, isConfiguring=%t)",
+						packetsR, packetAgeString(communication.LastPacketTimer), communication.IsConfiguring.IsSet()))
 					select {
 					case communication.HandleBootstrap <- "restart":
 						log.Log.Info("components.Kerberos.ControlAgent(): Restarting machinery because of blocking substream.")
@@ -507,6 +534,8 @@ func ControlAgent(communication *models.Communication) {
 
 					// After 15 seconds without activity this is thrown..
 					if occurenceSub == 3 {
+						log.Log.Info(fmt.Sprintf("components.Kerberos.ControlAgent(): substream stalled (stalledKeyframeCounter=%d, lastPacket=%s ago, isConfiguring=%t)",
+							packetsSubR, packetAgeString(communication.LastPacketTimerSub), communication.IsConfiguring.IsSet()))
 						select {
 						case communication.HandleBootstrap <- "restart":
 							log.Log.Info("components.Kerberos.ControlAgent(): Restarting machinery because of blocking substream.")
@@ -752,10 +781,24 @@ func GetSnapshotRaw(c *gin.Context, captureDevice *capture.Capture, configuratio
 // @Description Get the current configuration.
 // @Success 200
 func GetConfig(c *gin.Context, captureDevice *capture.Capture, configuration *models.Configuration, communication *models.Communication) {
-	// We'll try to get a snapshot from the camera.
-	base64Image := capture.Base64Image(captureDevice, communication, configuration)
-	if base64Image != "" {
-		communication.Image = base64Image
+	// We'll try to get a fresh snapshot from the camera. Capturing a snapshot
+	// reads a keyframe from the live stream, which blocks until one arrives.
+	// When the camera is offline or the stream is stalled (no packets being
+	// received) this would block the /config endpoint indefinitely, making the
+	// agent appear unreachable even though its HTTP server is healthy. We
+	// therefore bound the snapshot fetch with a short timeout and fall back to
+	// the last cached snapshot, so /config always responds promptly.
+	snapshot := make(chan string, 1)
+	go func() {
+		snapshot <- capture.Base64Image(captureDevice, communication, configuration)
+	}()
+	select {
+	case base64Image := <-snapshot:
+		if base64Image != "" {
+			communication.Image = base64Image
+		}
+	case <-time.After(2 * time.Second):
+		log.Log.Info("components.Kerberos.GetConfig(): snapshot timed out (stream stalled or camera offline), returning configuration with the last cached snapshot.")
 	}
 
 	c.JSON(200, gin.H{

machinery/src/config/main.go

@@ -193,8 +193,104 @@ func OpenConfig(configDirectory string, configuration *models.Configuration) {
 	return
 }
 
-// This function will override the configuration with environment variables.
+// OverrideWithEnvironmentVariables builds the effective configuration from the
+// environment variables.
+//
+// In ConfigMap/standalone mode (DEPLOYMENT empty or "agent") the global
+// configuration is delivered as GLOBAL_AGENT_* environment variables and the
+// per-agent configuration as AGENT_* environment variables. We parse them into
+// the separate global and custom configurations and build the effective
+// configuration as "global overridden by custom", mirroring the MongoDB-backed
+// factory behaviour. This keeps the global and per-agent (custom) configuration
+// separated so the factory edit page can distinguish inherited global settings
+// from per-agent overrides.
 func OverrideWithEnvironmentVariables(configuration *models.Configuration) {
+	if os.Getenv("DEPLOYMENT") == "" || os.Getenv("DEPLOYMENT") == "agent" {
+		initConfigPointers(&configuration.Config)
+
+		// Parse the global configuration from the GLOBAL_AGENT_* variables.
+		globalWrap := &models.Configuration{Config: configuration.GlobalConfig}
+		initConfigPointers(&globalWrap.Config)
+		applyAgentEnvVars(globalWrap, "GLOBAL_", false)
+		configuration.GlobalConfig = globalWrap.Config
+
+		// Parse the per-agent (custom) configuration from the AGENT_* variables.
+		// In ConfigMap mode the per-agent overrides are delivered exclusively
+		// through AGENT_* environment variables, so we must start from an empty
+		// configuration rather than the bundled config.json that OpenConfig loaded
+		// into CustomConfig. Otherwise defaults from that file (e.g. cloud="s3")
+		// would leak into the custom config and be mistaken for explicit per-agent
+		// overrides, hiding inherited global settings (the factory edit page would
+		// show the local default instead of the inherited global persistence).
+		customBase := configuration.CustomConfig
+		if isConfigMapMode() {
+			customBase = models.Config{}
+		}
+		customWrap := &models.Configuration{Config: customBase}
+		initConfigPointers(&customWrap.Config)
+		applyAgentEnvVars(customWrap, "", false)
+		configuration.CustomConfig = customWrap.Config
+
+		// Build the effective configuration: global base, then per-agent
+		// overrides on top. Defaults (e.g. signing) are applied on the last
+		// pass only.
+		applyAgentEnvVars(configuration, "GLOBAL_", false)
+		applyAgentEnvVars(configuration, "", true)
+	} else {
+		// Factory/MongoDB mode: the global and custom configurations are already
+		// loaded and merged from MongoDB; we only override the effective
+		// configuration with any AGENT_* environment variables.
+		applyAgentEnvVars(configuration, "", true)
+	}
+}
+
+// isConfigMapMode reports whether the agent is running in ConfigMap mode, i.e.
+// whether a global configuration layer is delivered separately through
+// GLOBAL_AGENT_* environment variables. In that mode the per-agent (custom)
+// configuration must be built solely from the AGENT_* overrides and must not be
+// seeded with the bundled config.json defaults, so that inherited global
+// settings remain distinguishable from explicit per-agent overrides.
+func isConfigMapMode() bool {
+	for _, env := range os.Environ() {
+		if strings.HasPrefix(env, "GLOBAL_AGENT_") {
+			return true
+		}
+	}
+	return false
+}
+
+// initConfigPointers ensures all pointer sub-structs are non-nil so that the
+// environment-variable parsing can assign into them without dereferencing a nil
+// pointer.
+func initConfigPointers(config *models.Config) {
+	if config.KStorage == nil {
+		config.KStorage = &models.KStorage{}
+	}
+	if config.KStorageSecondary == nil {
+		config.KStorageSecondary = &models.KStorage{}
+	}
+	if config.S3 == nil {
+		config.S3 = &models.S3{}
+	}
+	if config.Encryption == nil {
+		config.Encryption = &models.Encryption{}
+	}
+	if config.Signing == nil {
+		config.Signing = &models.Signing{}
+	}
+	if config.Dropbox == nil {
+		config.Dropbox = &models.Dropbox{}
+	}
+	if config.Region == nil {
+		config.Region = &models.Region{}
+	}
+}
+
+// applyAgentEnvVars applies the AGENT_* environment variables (optionally
+// carrying the given prefix, e.g. "GLOBAL_") onto configuration.Config. When
+// applyDefaults is true, defaults (such as the signing key) are applied after
+// parsing; this should only be done for the effective configuration.
+func applyAgentEnvVars(configuration *models.Configuration, prefix string, applyDefaults bool) {
 	environmentVariables := os.Environ()
 
 	// Initialize the configuration for some new fields.
@@ -203,9 +299,10 @@ func OverrideWithEnvironmentVariables(configuration *models.Configuration) {
 	}
 
 	for _, env := range environmentVariables {
-		if strings.Contains(env, "AGENT_") {
-			key := strings.Split(env, "=")[0]
-			value := os.Getenv(key)
+		fullKey := strings.SplitN(env, "=", 2)[0]
+		if strings.HasPrefix(fullKey, prefix+"AGENT_") && !(prefix == "" && strings.HasPrefix(fullKey, "GLOBAL_AGENT_")) {
+			key := strings.TrimPrefix(fullKey, prefix)
+			value := os.Getenv(fullKey)
 			switch key {
 
 			/* General configuration */
@@ -545,13 +642,20 @@ func OverrideWithEnvironmentVariables(configuration *models.Configuration) {
 		}
 	}
 
-	// Signing is a new feature, so if empty we set default values.
-	if configuration.Config.Signing == nil || configuration.Config.Signing.PrivateKey == "" {
+	// Signing is a new feature, so if empty we set default values. Only applied
+	// for the effective configuration (applyDefaults), not for the separate
+	// global/custom views.
+	if applyDefaults && (configuration.Config.Signing == nil || configuration.Config.Signing.PrivateKey == "") {
 		configuration.Config.Signing = &models.Signing{
 			Enabled:    "true",
 			PrivateKey: "-----BEGIN PRIVATE KEY-----\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\n-----END PRIVATE KEY-----",
 		}
 	}
+
+	// When the agent is configured through environment variables the global and
+	// custom configurations were already parsed separately (see
+	// OverrideWithEnvironmentVariables), so there is no need to mirror the
+	// effective configuration into CustomConfig anymore.
 }
 
 func SaveConfig(configDirectory string, config models.Config, configuration *models.Configuration, communication *models.Communication) error {

machinery/src/models/communication.go

@@ -37,9 +37,11 @@ type Communication struct {
 	HandleUpload          chan string
 	HandleHeartBeat       chan string
 	HandleLiveSD          chan int64
+	HandleLiveSDHTTP      chan int64
 	HandleLiveHDKeepalive chan string
 	HandleLiveHDHandshake chan LiveHDHandshake
 	HandleLiveHDPeers     chan string
+	HandleLiveHLS         chan int64
 	HandleONVIF           chan OnvifAction
 	IsConfiguring         *abool.AtomicBool
 	Queue                 *packets.Queue

machinery/src/models/mqtt.go

@@ -171,6 +171,19 @@ type UpdateConfigPayload struct {
 // We received a request SD stream request
 type RequestSDStreamPayload struct {
 	Timestamp int64 `json:"timestamp"` // timestamp
+	// Transport selects how the agent should deliver the preview frames for this
+	// viewer. "http" asks the agent to POST frames to hub-api (keeping them off
+	// MQTT); empty/absent means the legacy MQTT image push. Older agents simply
+	// ignore this unknown field and keep doing MQTT, and older frontends never set
+	// it — so new/old agents and frontends interoperate in every combination.
+	Transport string `json:"transport,omitempty"`
+}
+
+// We received a live HLS stream request. Like SD it is a simple viewer
+// keepalive: the agent owns the live HLS session, so the request only needs to
+// signal "a viewer is watching" to keep the segment pipeline alive.
+type RequestHLSStreamPayload struct {
+	Timestamp int64 `json:"timestamp"` // timestamp
 }
 
 // We received a request HD stream request

machinery/src/packets/packet.go

@@ -14,7 +14,7 @@ type Packet struct {
 	IsKeyFrame      bool   // video packet is key frame
 	Idx             int8   // stream index in container format
 	Codec           string // codec name
-	CompositionTime int64  // packet presentation time minus decode time for H264 B-Frame
+	CompositionTime int64  // composition offset (PTS - DTS) in milliseconds, non-zero for H264/H265 B-frames
 	Time            int64  // packet decode time
 	TimeLegacy      time.Duration
 	CurrentTime     int64  // current time in milliseconds (UNIX timestamp)

machinery/src/routers/http/jwt_middleware.go

@@ -14,7 +14,14 @@ import (
 func JWTMiddleWare() jwt.GinJWTMiddleware {
 
 	identityKey := "id"
-	myKey := "TOBECHANGED"
+	// Allow the JWT signing secret to be configured through an environment
+	// variable so that tokens issued by another service (e.g. the Kerberos
+	// Factory) can be validated by the agent. Falls back to the historic
+	// default to preserve backwards compatibility.
+	myKey := os.Getenv("AGENT_JWT_SECRET")
+	if myKey == "" {
+		myKey = "TOBECHANGED"
+	}
 
 	m := jwt.GinJWTMiddleware{
 		Realm:       "kerberosio",
@@ -106,7 +113,11 @@ func JWTMiddleWare() jwt.GinJWTMiddleware {
 		// - "query:<name>"
 		// - "cookie:<name>"
 		// - "param:<name>"
-		TokenLookup: "header: Authorization, query: token, cookie: jwt",
+		// X-Authorization is included because requests proxied through the
+		// Kubernetes apiserver service-proxy have their Authorization header
+		// consumed by the apiserver; the original bearer token is forwarded in
+		// the X-Authorization header instead.
+		TokenLookup: "header: Authorization, header: X-Authorization, query: token, cookie: jwt",
 		// TokenLookup: "query:token",
 		// TokenLookup: "cookie:token",
 

machinery/src/routers/mqtt/main.go

@@ -11,6 +11,7 @@ import (
 	"math/rand"
 	"strconv"
 	"strings"
+	"sync"
 	"time"
 
 	mqtt "github.com/eclipse/paho.mqtt.golang"
@@ -170,11 +171,45 @@ func ConfigureMQTT(configDirectory string, configuration *models.Configuration,
 	return nil
 }
 
-// maxSignalingAge is the maximum age of a WebRTC signaling message (request-hd-stream,
-// receive-hd-candidates) before it is considered stale and discarded. With CleanSession=false
-// the MQTT broker may replay queued messages from previous sessions; this prevents the agent
-// from setting up peer connections for viewers that are no longer waiting.
-const maxSignalingAge = 30 * time.Second
+// recentHDSessions tracks recently-seen WebRTC viewer session IDs so we can
+// dedupe duplicate request-hd-stream messages without relying on the broker's
+// (and the viewer's) wall clock. The viewer's offer-republish loop can fire
+// the same request several times for the same session_id while waiting for an
+// answer; the broker can also redeliver a message after a reconnect with
+// CleanSession=false. In both cases we want to handle the session exactly
+// once.
+//
+// Entries expire after recentHDSessionTTL. The map is small (one entry per
+// active viewer over the TTL window) so a periodic sweep is sufficient.
+const recentHDSessionTTL = 60 * time.Second
+
+var (
+	recentHDSessionsMu sync.Mutex
+	recentHDSessions   = make(map[string]time.Time)
+)
+
+// markHDSessionSeen returns true if this session_id was already processed
+// within the TTL window (i.e. this message should be treated as a duplicate).
+// It also opportunistically prunes expired entries.
+func markHDSessionSeen(sessionID string) bool {
+	if sessionID == "" {
+		return false
+	}
+	recentHDSessionsMu.Lock()
+	defer recentHDSessionsMu.Unlock()
+	now := time.Now()
+	// Lazy GC — cheap given the expected map size.
+	for k, t := range recentHDSessions {
+		if now.Sub(t) > recentHDSessionTTL {
+			delete(recentHDSessions, k)
+		}
+	}
+	if _, exists := recentHDSessions[sessionID]; exists {
+		return true
+	}
+	recentHDSessions[sessionID] = now
+	return false
+}
 
 func MQTTListenerHandler(mqttClient mqtt.Client, hubKey string, configDirectory string, configuration *models.Configuration, communication *models.Communication) {
 	if hubKey == "" {
@@ -282,16 +317,13 @@ func MQTTListenerHandler(mqttClient mqtt.Client, hubKey string, configDirectory
 				// We'll find out which message we received, and act accordingly.
 				log.Log.Info("routers.mqtt.main.MQTTListenerHandler(): received message with action: " + payload.Action)
 
-				// For time-sensitive WebRTC signaling messages, discard stale ones that may
-				// have been queued by the broker while CleanSession=false.
-				if payload.Action == "request-hd-stream" || payload.Action == "receive-hd-candidates" {
-					messageAge := time.Since(time.Unix(message.Timestamp, 0))
-					if messageAge > maxSignalingAge {
-						log.Log.Info("routers.mqtt.main.MQTTListenerHandler(): discarding stale " + payload.Action +
-							" message (age: " + messageAge.Round(time.Second).String() + ")")
-						return
-					}
-				}
+				// NOTE: We intentionally do NOT discard request-hd-stream /
+				// receive-hd-candidates messages based on a wall-clock age. The
+				// viewer and agent clocks can drift (especially on embedded
+				// devices), which previously caused valid requests to be
+				// silently dropped and forced the user to refresh the page.
+				// Duplicate handling for request-hd-stream is done by session_id
+				// inside HandleRequestHDStream (see markHDSessionSeen).
 
 				switch payload.Action {
 				case "record":
@@ -312,6 +344,8 @@ func MQTTListenerHandler(mqttClient mqtt.Client, hubKey string, configDirectory
 					go HandleRequestSDStream(mqttClient, hubKey, payload, configuration, communication)
 				case "request-hd-stream":
 					go HandleRequestHDStream(mqttClient, hubKey, payload, configuration, communication)
+				case "request-hls-stream":
+					go HandleRequestHLSStream(mqttClient, hubKey, payload, configuration, communication)
 				case "receive-hd-candidates":
 					go HandleReceiveHDCandidates(mqttClient, hubKey, payload, configuration, communication)
 				case "trigger-relay":
@@ -516,9 +550,20 @@ func HandleRequestSDStream(mqttClient mqtt.Client, hubKey string, payload models
 
 	if requestSDStreamPayload.Timestamp != 0 {
 		if communication.CameraConnected {
-			select {
-			case communication.HandleLiveSD <- time.Now().Unix():
-			default:
+			// A viewer that opted into the HTTP transport is signalled on a separate
+			// channel so the producer ships its frames to hub-api over HTTP instead of
+			// publishing them over MQTT. Any other (or absent) transport keeps the
+			// legacy MQTT image push, so older frontends behave exactly as before.
+			if requestSDStreamPayload.Transport == "http" {
+				select {
+				case communication.HandleLiveSDHTTP <- time.Now().Unix():
+				default:
+				}
+			} else {
+				select {
+				case communication.HandleLiveSD <- time.Now().Unix():
+				default:
+				}
 			}
 			log.Log.Info("routers.mqtt.main.HandleRequestSDStream(): received request to livestream.")
 		} else {
@@ -527,6 +572,30 @@ func HandleRequestSDStream(mqttClient mqtt.Client, hubKey string, payload models
 	}
 }
 
+// HandleRequestHLSStream is the viewer keepalive for live HLS. Like the SD
+// stream it simply signals that a viewer is watching; the agent owns the live
+// HLS session, so a single non-zero timestamp on the channel keeps the segment
+// pipeline alive (see cloud.HandleLiveStreamHLS). Viewers republish this
+// periodically; when the keepalives stop, the agent tears the session down.
+func HandleRequestHLSStream(mqttClient mqtt.Client, hubKey string, payload models.Payload, configuration *models.Configuration, communication *models.Communication) {
+	value := payload.Value
+	jsonData, _ := json.Marshal(value)
+	var requestHLSStreamPayload models.RequestHLSStreamPayload
+	json.Unmarshal(jsonData, &requestHLSStreamPayload)
+
+	if requestHLSStreamPayload.Timestamp != 0 {
+		if communication.CameraConnected {
+			select {
+			case communication.HandleLiveHLS <- time.Now().Unix():
+			default:
+			}
+			log.Log.Info("routers.mqtt.main.HandleRequestHLSStream(): received request to livestream over HLS.")
+		} else {
+			log.Log.Info("routers.mqtt.main.HandleRequestHLSStream(): received request to livestream over HLS, but camera is not connected.")
+		}
+	}
+}
+
 func HandleRequestHDStream(mqttClient mqtt.Client, hubKey string, payload models.Payload, configuration *models.Configuration, communication *models.Communication) {
 	value := payload.Value
 	// Convert map[string]interface{} to RequestHDStreamPayload
@@ -536,6 +605,15 @@ func HandleRequestHDStream(mqttClient mqtt.Client, hubKey string, payload models
 
 	if requestHDStreamPayload.Timestamp != 0 {
 		if communication.CameraConnected {
+			// Dedupe by session_id: the viewer republishes its offer while
+			// waiting for an answer (and the broker may redeliver), and we
+			// don't want to spawn multiple peer connections for the same
+			// browser session.
+			if markHDSessionSeen(requestHDStreamPayload.SessionID) {
+				log.Log.Info("routers.mqtt.main.HandleRequestHDStream(): duplicate request for session " +
+					requestHDStreamPayload.SessionID + ", ignoring")
+				return
+			}
 			// Set the Hub key, so we can send back the answer.
 			requestHDStreamPayload.HubKey = hubKey
 			if communication.HandleLiveHDHandshake == nil {

machinery/src/utils/main.go

@@ -427,12 +427,49 @@ func ResizeImage(img image.Image, newWidth uint, newHeight uint) (*image.Image,
 		return nil, errors.New("image is nil")
 	}
 
+	// Callers cast int->uint, so a negative or poisoned int (e.g. MinInt from
+	// `int(float * +Inf)` when the source width is 0) wraps to a near-MaxUint
+	// value here and crashes nfnt/resize's allocator with "makeslice: len out
+	// of range". Clamp anything past a sane camera ceiling to 0 ("auto" in
+	// nfnt — preserves aspect from the source).
+	const maxDim uint = 8192
+	if newWidth > maxDim {
+		newWidth = 0
+	}
+	if newHeight > maxDim {
+		newHeight = 0
+	}
+
 	// resize to width 640 using Lanczos resampling
 	// and preserve aspect ratio
 	m := resize.Resize(newWidth, newHeight, img, resize.Lanczos3)
 	return &m, nil
 }
 
+// ResolveBaseDimensions resolves the liveview/motion base dimensions for a
+// stream given the (optionally configured) base width/height and the camera's
+// probed source width/height. It returns the width and height that should be
+// stored on the configuration.
+//
+// The aspect-ratio branch is gated on width>0 && height>0: a not-yet-probed
+// stream has width=height=0, which previously made the ratio +Inf and
+// int(float * +Inf) yield MinInt. That poisoned value, later cast to uint at
+// the ResizeImage call sites, wrapped to ~MaxUint and crashed resize with
+// "makeslice: len out of range". When the source isn't probed yet we fall back
+// to the source dimensions (0,0 -> "auto") instead.
+func ResolveBaseDimensions(baseWidth, baseHeight, width, height int) (int, int) {
+	if baseWidth > 0 && baseHeight == 0 && width > 0 && height > 0 {
+		// Derive the height from the configured width and the source aspect ratio.
+		widthAspectRatio := float64(baseWidth) / float64(width)
+		return baseWidth, int(float64(height) * widthAspectRatio)
+	} else if baseHeight > 0 && baseWidth > 0 {
+		// Both base dimensions are configured; honor them as-is.
+		return baseWidth, baseHeight
+	}
+	// Nothing usable configured (or source not probed yet): use source dimensions.
+	return width, height
+}
+
 func ResizeHeightWithAspectRatio(newWidth int, width int, height int) (int, int) {
 	if newWidth <= 0 || width <= 0 || height <= 0 {
 		return width, height

machinery/src/utils/resize_test.go

@@ -0,0 +1,124 @@
+package utils
+
+import (
+	"image"
+	"math"
+	"testing"
+)
+
+func TestResolveBaseDimensions(t *testing.T) {
+	tests := []struct {
+		name                  string
+		baseWidth, baseHeight int
+		width, height         int
+		wantWidth, wantHeight int
+	}{
+		{
+			name:      "base width set, height derived from aspect ratio",
+			baseWidth: 640, baseHeight: 0,
+			width: 1920, height: 1080,
+			wantWidth: 640, wantHeight: 360,
+		},
+		{
+			name:      "both base dimensions configured are honored",
+			baseWidth: 640, baseHeight: 480,
+			width: 1920, height: 1080,
+			wantWidth: 640, wantHeight: 480,
+		},
+		{
+			name:      "no base configured falls back to source dimensions",
+			baseWidth: 0, baseHeight: 0,
+			width: 1920, height: 1080,
+			wantWidth: 1920, wantHeight: 1080,
+		},
+		{
+			// Regression: a not-yet-probed stream has width=height=0. The old
+			// aspect-ratio branch divided by zero (float * +Inf -> MinInt) and
+			// poisoned BaseHeight, later crashing resize with makeslice panic.
+			name:      "unprobed stream (width=0) does not poison dimensions",
+			baseWidth: 640, baseHeight: 0,
+			width: 0, height: 0,
+			wantWidth: 0, wantHeight: 0,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			gotWidth, gotHeight := ResolveBaseDimensions(tt.baseWidth, tt.baseHeight, tt.width, tt.height)
+			if gotWidth != tt.wantWidth || gotHeight != tt.wantHeight {
+				t.Fatalf("ResolveBaseDimensions(%d,%d,%d,%d) = (%d,%d), want (%d,%d)",
+					tt.baseWidth, tt.baseHeight, tt.width, tt.height,
+					gotWidth, gotHeight, tt.wantWidth, tt.wantHeight)
+			}
+		})
+	}
+}
+
+func TestResolveBaseDimensionsNeverNegative(t *testing.T) {
+	// Whatever the inputs, the resolved dimensions must never be negative,
+	// otherwise the uint cast at the resize call sites wraps to ~MaxUint.
+	for _, c := range [][4]int{
+		{640, 0, 0, 0},
+		{640, 0, 0, 1080},
+		{640, 0, 1920, 0},
+		{0, 0, 0, 0},
+	} {
+		w, h := ResolveBaseDimensions(c[0], c[1], c[2], c[3])
+		if w < 0 || h < 0 {
+			t.Fatalf("ResolveBaseDimensions(%v) produced negative dims (%d,%d)", c, w, h)
+		}
+	}
+}
+
+func TestResizeImageClampsPoisonedDimensions(t *testing.T) {
+	src := image.NewRGBA(image.Rect(0, 0, 320, 240))
+
+	// uint(math.MinInt) is the value produced when a poisoned int (from
+	// int(float * +Inf)) is cast to uint at a call site. It must not panic
+	// nfnt/resize's allocator; it should fall back to source-aspect resize.
+	// Compute via a runtime int so the conversion doesn't overflow at compile time.
+	minInt := math.MinInt
+	poison := uint(minInt)
+
+	resized, err := ResizeImage(src, poison, poison)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if resized == nil {
+		t.Fatalf("expected an image, got nil")
+	}
+	b := (*resized).Bounds()
+	if b.Dx() != 320 || b.Dy() != 240 {
+		t.Fatalf("poisoned dims should fall back to source size, got %dx%d", b.Dx(), b.Dy())
+	}
+}
+
+func TestResizeImageClampsAboveCameraCeiling(t *testing.T) {
+	src := image.NewRGBA(image.Rect(0, 0, 320, 240))
+
+	// A width beyond any sane camera resolution is treated as "auto" (0).
+	resized, err := ResizeImage(src, 100000, 0)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	b := (*resized).Bounds()
+	if b.Dx() != 320 || b.Dy() != 240 {
+		t.Fatalf("oversized width should fall back to source size, got %dx%d", b.Dx(), b.Dy())
+	}
+}
+
+func TestResizeImageNormalResizeStillWorks(t *testing.T) {
+	src := image.NewRGBA(image.Rect(0, 0, 1920, 1080))
+
+	resized, err := ResizeImage(src, 640, 0)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	b := (*resized).Bounds()
+	if b.Dx() != 640 {
+		t.Fatalf("expected width 640, got %d", b.Dx())
+	}
+	if b.Dy() != 360 {
+		t.Fatalf("expected aspect-preserved height 360, got %d", b.Dy())
+	}
+}

machinery/src/video/livehls.go

@@ -0,0 +1,586 @@
+package video
+
+import (
+	"bytes"
+	"fmt"
+
+	mp4ff "github.com/Eyevinn/mp4ff/mp4"
+	"github.com/kerberos-io/agent/machinery/src/log"
+)
+
+// LiveSegmenter turns a live stream of Annex B video samples into HLS-ready
+// fragmented-MP4 (CMAF) output: ONE init segment (ftyp+moov) followed by a
+// series of INDEPENDENT media segments (styp+moof+mdat), each beginning with a
+// keyframe and carrying its own tfdt. This is the building block for the live
+// HLS pipeline (agent -> hub-api -> vault -> hub-frontend) and is intentionally
+// kept separate from the recording muxer in mp4.go:
+//
+//   - mp4.go writes ONE fragmented MP4 per recording (free-box placeholder up
+//     front, back-filled on Close). That layout is great for archived files but
+//     useless for live, where each segment must be shippable the instant it is
+//     produced and must decode on its own after the init segment.
+//   - LiveSegmenter emits discrete, self-contained segments via callbacks, so
+//     the transport (single-POST to hub-api, drop-on-failure) never has to wait
+//     for the recording to finish.
+//
+// Both producers use the SAME mp4ff fragment format, so live and archived video
+// share one toolchain on the player side (hls.js #EXT-X-MAP + byte-range parts).
+//
+// The spike scope is video-only H.264/H.265. Audio and multi-track interleaving
+// can be layered on later by adding tracks to the init segment and a second trun
+// to each fragment; nothing here precludes that.
+type LiveSegmenter struct {
+	// codec is "H264"/"H265" (case handled in buildInit).
+	codec string
+	// timescale is the media timescale used in the init segment. The agent's
+	// capture path feeds presentation timestamps in milliseconds, so a 1000-tick
+	// timescale keeps sample durations exact with no rescaling.
+	timescale uint32
+	// targetSegmentMs is the minimum amount of media a segment accumulates before
+	// the next keyframe is allowed to start a fresh segment. Keeping segments
+	// keyframe-aligned is what makes each one independently decodable.
+	targetSegmentMs uint64
+
+	spsNALUs [][]byte
+	ppsNALUs [][]byte
+	vpsNALUs [][]byte
+
+	// width/height are written into the visual sample entry. They are optional:
+	// on a successful strict SPS parse mp4ff derives them, but the manual avcC
+	// fallback (used for SPS that mp4ff cannot parse) needs them supplied.
+	width  uint16
+	height uint16
+
+	videoTrackID uint32
+
+	initSegment *mp4ff.InitSegment
+	initBytes   []byte
+	initEmitted bool
+
+	seg   *mp4ff.MediaSegment
+	frag  *mp4ff.Fragment
+	seqNr uint32
+
+	// started becomes true once the first segment has been opened.
+	started bool
+	// segStartPTS is the decode time (ms) of the first sample in the open
+	// segment; elapsed media is measured against it to decide segment cuts.
+	segStartPTS uint64
+	// segDurationMs accumulates the committed sample durations of the open
+	// segment so the playlist can advertise an accurate #EXTINF.
+	segDurationMs uint64
+
+	// pending holds the most recently received sample. Its duration is only known
+	// once the NEXT sample arrives (duration = nextPTS - thisPTS), mirroring the
+	// pending-sample pattern used by the recording muxer.
+	pending *mp4ff.FullSample
+	// lastDurationMs is the previous committed duration, reused to close out the
+	// final pending sample (and to bridge non-monotonic timestamps).
+	lastDurationMs uint64
+
+	// OnInit is invoked exactly once with the encoded init segment bytes before
+	// the first media segment is emitted. Optional.
+	OnInit func(initBytes []byte) error
+	// OnSegment is invoked once per completed media segment. Optional. It is left
+	// unused in low-latency mode (see OnPart).
+	OnSegment func(seg LiveSegment) error
+
+	// --- Low-latency (LL-HLS) partial-segment mode ---
+	//
+	// When partTargetMs > 0 the segmenter additionally slices each segment into
+	// ~partTargetMs CMAF "parts" (chunks) and emits them via OnPart the instant
+	// each one closes, instead of waiting for the whole segment. The classic
+	// per-segment OnSegment path above is left untouched (and unused) in this mode.
+	// Each part is one mp4ff fragment (moof+mdat); part 0 of a segment also carries
+	// the CMAF styp, so concatenating a segment's parts yields one valid segment.
+	partTargetMs uint64
+	// partFrag is the open part's fragment; partIndex is its 0-based index within
+	// the current segment; fragSeq is the globally monotonic moof sequence number
+	// shared across all parts (MSE wants increasing moof sequence numbers).
+	partFrag        *mp4ff.Fragment
+	partIndex       uint32
+	fragSeq         uint32
+	partSampleCount int
+	partDurationMs  uint64
+	partIndependent bool
+	// OnPart is invoked once per completed CMAF part when partTargetMs > 0.
+	OnPart func(part LivePart) error
+}
+
+// LiveSegment is one independently-decodable CMAF media segment.
+type LiveSegment struct {
+	// SequenceNumber is the monotonically increasing fragment sequence number
+	// (also used as the moof sequence number and the seg-N.m4s index).
+	SequenceNumber uint32
+	// DurationMs is the summed sample duration of the segment, for #EXTINF.
+	DurationMs uint64
+	// Data is the complete styp+moof+mdat segment, ready to append after the init
+	// segment and hand to hls.js / a vault object.
+	Data []byte
+}
+
+// LivePart is one CMAF partial segment (chunk) of a media segment, emitted in
+// low-latency mode the instant it closes - before the whole segment is done - so
+// the playlist can advertise it via #EXT-X-PART for near-live playback.
+type LivePart struct {
+	// SegmentSeq is the parent media segment's sequence number (the N in
+	// seg-N.K.m4s); PartIndex is K within that segment (0-based).
+	SegmentSeq uint32
+	PartIndex  uint32
+	// Independent is true when the part begins with a keyframe (its first sample is
+	// an IDR), i.e. it is independently decodable (#EXT-X-PART INDEPENDENT=YES).
+	Independent bool
+	// DurationMs is the summed sample duration of the part (for #EXT-X-PART).
+	DurationMs uint64
+	// Data of part 0 is styp+moof+mdat; later parts are bare moof+mdat, so
+	// concatenating a segment's parts in order yields one valid CMAF segment.
+	Data []byte
+}
+
+// Sample-entry flags matching the recording muxer so live and archived fragments
+// describe random access points identically.
+//
+//	keyframe     0x02000000 = sampleDependsOn=2 (depends on nothing), sync sample
+//	non-keyframe 0x01010000 = sampleDependsOn=1, sampleIsNonSyncSample=1
+const (
+	liveSyncSampleFlags    uint32 = 0x02000000
+	liveNonSyncSampleFlags uint32 = 0x01010000
+	// liveFallbackDurationMs is used when a duration cannot be derived (first
+	// frame at Close, or non-monotonic timestamps) and no prior duration exists.
+	// ~33 ms approximates 30 fps and is only ever a single-frame nicety.
+	liveFallbackDurationMs uint64 = 33
+)
+
+// NewLiveSegmenter creates a video-only live segmenter for the given codec.
+// spsNALUs/ppsNALUs (and vpsNALUs for H.265) may be raw NAL units or Annex B
+// blobs with start codes; both are normalized. targetSegmentMs is clamped to a
+// sane floor so a misconfiguration cannot produce one-frame segments.
+func NewLiveSegmenter(codec string, spsNALUs, ppsNALUs, vpsNALUs [][]byte, targetSegmentMs uint64) *LiveSegmenter {
+	if targetSegmentMs < 500 {
+		targetSegmentMs = 500
+	}
+	return &LiveSegmenter{
+		codec:           codec,
+		timescale:       1000,
+		targetSegmentMs: targetSegmentMs,
+		spsNALUs:        spsNALUs,
+		ppsNALUs:        ppsNALUs,
+		vpsNALUs:        vpsNALUs,
+	}
+}
+
+// SetDimensions records the encoded video width/height in pixels. They are
+// written into the avc1/hvc1 visual sample entry and are required for the manual
+// descriptor fallback path (SPS that mp4ff's strict parser rejects).
+func (ls *LiveSegmenter) SetDimensions(width, height uint16) {
+	ls.width = width
+	ls.height = height
+}
+
+// EnableLowLatency switches the segmenter into LL-HLS mode, additionally slicing
+// each segment into ~partTargetMs CMAF parts emitted via OnPart as they close.
+// partTargetMs is clamped to a sane floor. Call before the first WriteSample.
+func (ls *LiveSegmenter) EnableLowLatency(partTargetMs uint64) {
+	if partTargetMs < 100 {
+		partTargetMs = 100
+	}
+	ls.partTargetMs = partTargetMs
+}
+
+// InitSegment returns the encoded init segment bytes, building them on demand.
+// Useful for tests and for serving the #EXT-X-MAP target without waiting for the
+// first media segment.
+func (ls *LiveSegmenter) InitSegment() ([]byte, error) {
+	if ls.initBytes == nil {
+		if err := ls.buildInit(); err != nil {
+			return nil, err
+		}
+	}
+	return ls.initBytes, nil
+}
+
+// buildInit constructs the ftyp+moov init segment from the parameter sets.
+func (ls *LiveSegmenter) buildInit() error {
+	init := mp4ff.CreateEmptyInit()
+	init.AddEmptyTrack(ls.timescale, "video", "und")
+	trak := init.Moov.Traks[0]
+
+	switch ls.codec {
+	case "H264", "h264", "AVC", "avc", "AVC1", "avc1":
+		sps, pps := normalizeH264ParameterSets(ls.spsNALUs, ls.ppsNALUs)
+		if len(sps) == 0 || len(pps) == 0 {
+			return fmt.Errorf("livehls: missing H264 SPS/PPS (sps=%d pps=%d)", len(sps), len(pps))
+		}
+		// includePS=true stores SPS/PPS in the avcC so segments need not carry
+		// in-band parameter sets - browsers read them from the init segment. Some
+		// camera SPS variants trip mp4ff's strict parser (e.g. unusual VUI/SAR);
+		// fall back to a manually built avcC just like the recording muxer does so
+		// those cameras still produce a valid init segment.
+		if err := trak.SetAVCDescriptor("avc1", sps, pps, true); err != nil {
+			log.Log.Warning("livehls: SetAVCDescriptor failed, using manual avcC fallback: " + err.Error())
+			if fbErr := addAVCDescriptorFallback(trak, sps, pps, ls.width, ls.height); fbErr != nil {
+				return fmt.Errorf("livehls: AVC descriptor fallback: %w", fbErr)
+			}
+		}
+	case "H265", "h265", "HEVC", "hevc", "HVC1", "hvc1":
+		vps, sps, pps := normalizeH265ParameterSets(ls.vpsNALUs, ls.spsNALUs, ls.ppsNALUs)
+		if len(vps) == 0 || len(sps) == 0 || len(pps) == 0 {
+			return fmt.Errorf("livehls: missing H265 VPS/SPS/PPS (vps=%d sps=%d pps=%d)", len(vps), len(sps), len(pps))
+		}
+		if err := trak.SetHEVCDescriptor("hvc1", vps, sps, pps, [][]byte{}, true); err != nil {
+			return fmt.Errorf("livehls: SetHEVCDescriptor: %w", err)
+		}
+	default:
+		return fmt.Errorf("livehls: unsupported codec %q", ls.codec)
+	}
+
+	// Record the encoded dimensions in the track header when known.
+	if ls.width > 0 && ls.height > 0 {
+		trak.Tkhd.Width = mp4ff.Fixed32(uint32(ls.width) << 16)
+		trak.Tkhd.Height = mp4ff.Fixed32(uint32(ls.height) << 16)
+	}
+	// mdhd.Duration MUST be 0 for fragmented MP4 so players derive duration from
+	// the fragments rather than a (here unknown) total.
+	trak.Mdia.Mdhd.Duration = 0
+
+	ls.videoTrackID = trak.Tkhd.TrackID
+
+	var buf bytes.Buffer
+	if err := init.Encode(&buf); err != nil {
+		return fmt.Errorf("livehls: encode init: %w", err)
+	}
+	ls.initSegment = init
+	ls.initBytes = buf.Bytes()
+	return nil
+}
+
+// WriteSample feeds one Annex B access unit with its decode timestamp (DTS) in
+// milliseconds. The first sample of a session MUST be a keyframe; a non-keyframe
+// first sample is dropped (it could not be decoded without a preceding IDR).
+//
+// compositionOffsetMs is the CTS offset (PTS-DTS, for B-frame reordering) in
+// timescale ticks; pass 0 for streams without B-frames.
+func (ls *LiveSegmenter) WriteSample(isKeyframe bool, annexB []byte, ptsMs uint64, compositionOffsetMs int32) error {
+	// Lazily build + emit the init segment on the first accepted sample.
+	if ls.initBytes == nil {
+		if err := ls.buildInit(); err != nil {
+			return err
+		}
+	}
+	if !ls.initEmitted {
+		ls.initEmitted = true
+		if ls.OnInit != nil {
+			if err := ls.OnInit(ls.initBytes); err != nil {
+				return err
+			}
+		}
+	}
+
+	// A session must open on a random-access point; otherwise the first segment
+	// would reference frames that never arrived.
+	if !ls.started && !isKeyframe {
+		log.Log.Debug("LiveSegmenter.WriteSample(): dropping leading non-keyframe before first IDR")
+		return nil
+	}
+
+	lengthPrefixed, err := annexBToLengthPrefixed(annexB)
+	if err != nil {
+		return fmt.Errorf("livehls: convert AnnexB: %w", err)
+	}
+
+	// Low-latency mode slices each segment into parts; the classic per-segment path
+	// below is left exactly as-is for the default (non-LL) configuration.
+	if ls.partTargetMs > 0 {
+		return ls.writeSampleLL(isKeyframe, lengthPrefixed, ptsMs, compositionOffsetMs)
+	}
+
+	// The previous sample's duration is the gap to this sample's PTS. Commit it
+	// to the (still open) current fragment before we consider rolling segments,
+	// because the pending sample always precedes this one in decode order.
+	if ls.pending != nil {
+		dur := ls.lastDurationMs
+		if ptsMs > ls.pending.DecodeTime {
+			dur = ptsMs - ls.pending.DecodeTime
+		}
+		if dur == 0 {
+			dur = liveFallbackDurationMs
+		}
+		ls.lastDurationMs = dur
+		ls.pending.Sample.Dur = uint32(dur)
+		if err := ls.commitPending(); err != nil {
+			return err
+		}
+	}
+
+	// At every keyframe, decide whether enough media has accumulated to close the
+	// open segment and start a new one. Cutting only on keyframes guarantees each
+	// segment is independently decodable.
+	if isKeyframe {
+		shouldCut := !ls.started || (ptsMs-ls.segStartPTS) >= ls.targetSegmentMs
+		if shouldCut {
+			if ls.started {
+				if err := ls.emitSegment(); err != nil {
+					return err
+				}
+			}
+			ls.openSegment(ptsMs)
+		}
+	}
+
+	// Stage this sample; its duration is filled in when the next sample arrives
+	// (or at Close()).
+	flags := liveNonSyncSampleFlags
+	if isKeyframe {
+		flags = liveSyncSampleFlags
+	}
+	ls.pending = &mp4ff.FullSample{
+		Sample: mp4ff.Sample{
+			Flags:                 flags,
+			Size:                  uint32(len(lengthPrefixed)),
+			CompositionTimeOffset: compositionOffsetMs,
+		},
+		DecodeTime: ptsMs,
+		Data:       lengthPrefixed,
+	}
+	return nil
+}
+
+// openSegment starts a fresh media segment (with CMAF styp) and an empty
+// single-track fragment whose moof sequence number is the segment index.
+func (ls *LiveSegmenter) openSegment(startPTS uint64) {
+	ls.seqNr++
+	ls.seg = mp4ff.NewMediaSegment() // includes a CMAF styp box by default
+	frag, err := mp4ff.CreateFragment(ls.seqNr, ls.videoTrackID)
+	if err != nil {
+		log.Log.Error("LiveSegmenter.openSegment(): CreateFragment failed: " + err.Error())
+		return
+	}
+	ls.seg.AddFragment(frag)
+	ls.frag = frag
+	ls.segStartPTS = startPTS
+	ls.segDurationMs = 0
+	ls.started = true
+}
+
+// commitPending appends the staged sample to the open fragment. The first sample
+// of a fragment seeds the tfdt baseMediaDecodeTime from its absolute DecodeTime,
+// which is what makes the segment independently seekable/decodable.
+func (ls *LiveSegmenter) commitPending() error {
+	if ls.pending == nil {
+		return nil
+	}
+	if ls.frag == nil {
+		// No open segment yet (e.g. pending set before the first keyframe cut). The
+		// keyframe path always opens a segment before staging, so this only guards
+		// against logic drift; drop rather than panic.
+		ls.pending = nil
+		return nil
+	}
+	if err := ls.frag.AddFullSampleToTrack(*ls.pending, ls.videoTrackID); err != nil {
+		return fmt.Errorf("livehls: AddFullSampleToTrack: %w", err)
+	}
+	ls.segDurationMs += uint64(ls.pending.Sample.Dur)
+	ls.pending = nil
+	return nil
+}
+
+// emitSegment encodes the open segment and hands it to OnSegment.
+func (ls *LiveSegmenter) emitSegment() error {
+	if ls.seg == nil {
+		return nil
+	}
+	var buf bytes.Buffer
+	if err := ls.seg.Encode(&buf); err != nil {
+		return fmt.Errorf("livehls: encode segment %d: %w", ls.seqNr, err)
+	}
+	out := LiveSegment{
+		SequenceNumber: ls.seqNr,
+		DurationMs:     ls.segDurationMs,
+		Data:           buf.Bytes(),
+	}
+	ls.seg = nil
+	ls.frag = nil
+	if ls.OnSegment != nil {
+		return ls.OnSegment(out)
+	}
+	return nil
+}
+
+// Close flushes the final pending sample and emits the last open segment (or, in
+// low-latency mode, the last open part). Call once when the live session ends so
+// no trailing media is lost.
+func (ls *LiveSegmenter) Close() error {
+	if ls.partTargetMs > 0 {
+		if ls.pending != nil {
+			dur := ls.lastDurationMs
+			if dur == 0 {
+				dur = liveFallbackDurationMs
+			}
+			ls.pending.Sample.Dur = uint32(dur)
+			if err := ls.commitPendingPart(); err != nil {
+				return err
+			}
+		}
+		return ls.closePart()
+	}
+	if ls.pending != nil {
+		dur := ls.lastDurationMs
+		if dur == 0 {
+			dur = liveFallbackDurationMs
+		}
+		ls.pending.Sample.Dur = uint32(dur)
+		if err := ls.commitPending(); err != nil {
+			return err
+		}
+	}
+	return ls.emitSegment()
+}
+
+// writeSampleLL is the low-latency counterpart of the per-segment staging in
+// WriteSample: it commits the previous sample into the open part, rolls the part
+// (every ~partTargetMs) and the segment (at keyframes, every ~targetSegmentMs),
+// then stages the current sample. Parts are emitted via OnPart as they close.
+func (ls *LiveSegmenter) writeSampleLL(isKeyframe bool, lengthPrefixed []byte, ptsMs uint64, compositionOffsetMs int32) error {
+	if ls.pending != nil {
+		dur := ls.lastDurationMs
+		if ptsMs > ls.pending.DecodeTime {
+			dur = ptsMs - ls.pending.DecodeTime
+		}
+		if dur == 0 {
+			dur = liveFallbackDurationMs
+		}
+		ls.lastDurationMs = dur
+		ls.pending.Sample.Dur = uint32(dur)
+		if err := ls.commitPendingPart(); err != nil {
+			return err
+		}
+	}
+
+	// Roll the segment at keyframes once enough media accumulated; otherwise roll a
+	// part once it reaches the part target. The two are mutually exclusive: a
+	// keyframe cut also closes the current part.
+	cut := false
+	if isKeyframe {
+		cut = !ls.started || (ptsMs-ls.segStartPTS) >= ls.targetSegmentMs
+	}
+	switch {
+	case cut:
+		if ls.started {
+			if err := ls.closePart(); err != nil {
+				return err
+			}
+		}
+		ls.openSegmentLL(ptsMs)
+	case ls.started && ls.partDurationMs >= ls.partTargetMs:
+		if err := ls.closePart(); err != nil {
+			return err
+		}
+		ls.openPartLL()
+	}
+
+	flags := liveNonSyncSampleFlags
+	if isKeyframe {
+		flags = liveSyncSampleFlags
+	}
+	ls.pending = &mp4ff.FullSample{
+		Sample: mp4ff.Sample{
+			Flags:                 flags,
+			Size:                  uint32(len(lengthPrefixed)),
+			CompositionTimeOffset: compositionOffsetMs,
+		},
+		DecodeTime: ptsMs,
+		Data:       lengthPrefixed,
+	}
+	return nil
+}
+
+// commitPendingPart appends the staged sample to the open part fragment, marking
+// the part independent when its first sample is a keyframe.
+func (ls *LiveSegmenter) commitPendingPart() error {
+	if ls.pending == nil {
+		return nil
+	}
+	if ls.partFrag == nil {
+		// No open part yet (pending staged before the first keyframe cut). The cut
+		// path always opens a part before staging, so this only guards against logic
+		// drift; drop rather than panic.
+		ls.pending = nil
+		return nil
+	}
+	first := ls.partSampleCount == 0
+	if err := ls.partFrag.AddFullSampleToTrack(*ls.pending, ls.videoTrackID); err != nil {
+		return fmt.Errorf("livehls: AddFullSampleToTrack: %w", err)
+	}
+	if first && ls.pending.Sample.Flags == liveSyncSampleFlags {
+		ls.partIndependent = true
+	}
+	ls.partSampleCount++
+	ls.partDurationMs += uint64(ls.pending.Sample.Dur)
+	ls.segDurationMs += uint64(ls.pending.Sample.Dur)
+	ls.pending = nil
+	return nil
+}
+
+// openSegmentLL starts a fresh media segment at a keyframe by opening its part 0.
+func (ls *LiveSegmenter) openSegmentLL(startPTS uint64) {
+	ls.seqNr++
+	ls.partIndex = 0
+	ls.segStartPTS = startPTS
+	ls.segDurationMs = 0
+	ls.started = true
+	ls.openPartFragment()
+}
+
+// openPartLL starts the next part within the current segment.
+func (ls *LiveSegmenter) openPartLL() {
+	ls.partIndex++
+	ls.openPartFragment()
+}
+
+// openPartFragment allocates a fresh single-track fragment (one moof+mdat) for
+// the next part, with a globally monotonic moof sequence number.
+func (ls *LiveSegmenter) openPartFragment() {
+	ls.fragSeq++
+	frag, err := mp4ff.CreateFragment(ls.fragSeq, ls.videoTrackID)
+	if err != nil {
+		log.Log.Error("LiveSegmenter.openPartFragment(): CreateFragment failed: " + err.Error())
+		return
+	}
+	ls.partFrag = frag
+	ls.partSampleCount = 0
+	ls.partDurationMs = 0
+	ls.partIndependent = false
+}
+
+// closePart encodes the open part and hands it to OnPart. Part 0 of a segment
+// carries the CMAF styp; later parts are bare moof+mdat, so a segment's parts
+// concatenate into one valid segment. Empty parts are skipped.
+func (ls *LiveSegmenter) closePart() error {
+	if ls.partFrag == nil || ls.partSampleCount == 0 {
+		return nil
+	}
+	var buf bytes.Buffer
+	if ls.partIndex == 0 {
+		seg := mp4ff.NewMediaSegment() // includes a CMAF styp box by default
+		seg.AddFragment(ls.partFrag)
+		if err := seg.Encode(&buf); err != nil {
+			return fmt.Errorf("livehls: encode part %d.%d: %w", ls.seqNr, ls.partIndex, err)
+		}
+	} else {
+		if err := ls.partFrag.Encode(&buf); err != nil {
+			return fmt.Errorf("livehls: encode part %d.%d: %w", ls.seqNr, ls.partIndex, err)
+		}
+	}
+	out := LivePart{
+		SegmentSeq:  ls.seqNr,
+		PartIndex:   ls.partIndex,
+		Independent: ls.partIndependent,
+		DurationMs:  ls.partDurationMs,
+		Data:        buf.Bytes(),
+	}
+	ls.partFrag = nil
+	if ls.OnPart != nil {
+		return ls.OnPart(out)
+	}
+	return nil
+}

machinery/src/video/livehls_test.go

@@ -0,0 +1,554 @@
+package video
+
+import (
+	"bytes"
+	"fmt"
+	"math"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	mp4ff "github.com/Eyevinn/mp4ff/mp4"
+)
+
+// Known-good minimal H.264 baseline parameter sets (640x480), reused from the
+// recording-muxer tests so the live segmenter is exercised against the exact
+// SPS/PPS mp4ff is already known to parse into an avcC descriptor.
+var (
+	liveTestSPS = []byte{0x67, 0x42, 0xc0, 0x1e, 0xd9, 0x00, 0xa0, 0x47, 0xfe, 0xc8}
+	liveTestPPS = []byte{0x68, 0xce, 0x38, 0x80}
+)
+
+// makeAnnexBFrame builds a single-NALU Annex B access unit: a 4-byte start code,
+// the NAL header (IDR=0x65 for keyframes, non-IDR=0x01 otherwise) and padding.
+func makeAnnexBFrame(isKey bool) []byte {
+	nalType := byte(0x01)
+	if isKey {
+		nalType = 0x65
+	}
+	frame := []byte{0x00, 0x00, 0x00, 0x01, nalType}
+	for i := 0; i < 100; i++ {
+		frame = append(frame, byte(i))
+	}
+	return frame
+}
+
+// isSyncSample reports whether a parsed sample is a random-access point
+// (sample_depends_on == 2 => "depends on nothing" => IDR/sync).
+func isSyncSample(s mp4ff.Sample) bool {
+	return (s.Flags>>24)&0x03 == 0x02
+}
+
+// TestLiveSegmenterProducesIndependentCMAFSegments feeds a synthetic H.264
+// stream (25 fps, 1s GOPs) through the live segmenter and asserts that:
+//   - exactly one init segment (ftyp+moov, single avc1 video track) is produced;
+//   - segments are cut on keyframe boundaries honoring the target duration;
+//   - every media segment carries a CMAF styp + exactly one moof+mdat fragment;
+//   - each segment begins with a sync sample and its tfdt equals the absolute
+//     decode time of that first sample (the property that makes it independently
+//     decodable after the init segment);
+//   - sample counts and durations are preserved end to end.
+func TestLiveSegmenterProducesIndependentCMAFSegments(t *testing.T) {
+	const (
+		frameDurMs = uint64(40) // 25 fps
+		gopFrames  = 25         // keyframe every 1000 ms
+		numGOPs    = 6
+		numFrames  = gopFrames * numGOPs // 150 frames, 6000 ms
+		targetMs   = uint64(2000)        // 2s segments => 2 GOPs each
+	)
+
+	seg := NewLiveSegmenter("H264", [][]byte{liveTestSPS}, [][]byte{liveTestPPS}, nil, targetMs)
+	seg.SetDimensions(640, 480)
+
+	var initBytes []byte
+	var initCalls int
+	var segments []LiveSegment
+	seg.OnInit = func(b []byte) error {
+		initCalls++
+		initBytes = append([]byte(nil), b...)
+		return nil
+	}
+	seg.OnSegment = func(s LiveSegment) error {
+		segments = append(segments, s)
+		return nil
+	}
+
+	for i := 0; i < numFrames; i++ {
+		isKey := i%gopFrames == 0
+		pts := uint64(i) * frameDurMs
+		if err := seg.WriteSample(isKey, makeAnnexBFrame(isKey), pts, 0); err != nil {
+			t.Fatalf("WriteSample(frame=%d): %v", i, err)
+		}
+	}
+	if err := seg.Close(); err != nil {
+		t.Fatalf("Close: %v", err)
+	}
+
+	// --- Init segment: emitted exactly once, well-formed, single video track. ---
+	if initCalls != 1 {
+		t.Fatalf("OnInit called %d times, want 1", initCalls)
+	}
+	if len(initBytes) == 0 {
+		t.Fatal("init segment is empty")
+	}
+	parsedInit, err := mp4ff.DecodeFile(bytes.NewReader(initBytes))
+	if err != nil {
+		t.Fatalf("decode init: %v", err)
+	}
+	if parsedInit.Init == nil || parsedInit.Init.Ftyp == nil || parsedInit.Init.Moov == nil {
+		t.Fatal("init segment missing ftyp/moov")
+	}
+	if got := len(parsedInit.Init.Moov.Traks); got != 1 {
+		t.Fatalf("init moov has %d traks, want 1", got)
+	}
+
+	// --- Segment cut cadence: 6 GOPs at 2s target => 3 segments of 2 GOPs each. ---
+	const wantSegments = 3
+	if len(segments) != wantSegments {
+		t.Fatalf("got %d media segments, want %d", len(segments), wantSegments)
+	}
+	for i, s := range segments {
+		if want := uint32(i + 1); s.SequenceNumber != want {
+			t.Errorf("segment %d: SequenceNumber=%d, want %d", i, s.SequenceNumber, want)
+		}
+		if s.DurationMs != targetMs {
+			t.Errorf("segment %d: DurationMs=%d, want %d", i, s.DurationMs, targetMs)
+		}
+	}
+
+	// --- Each segment must decode INDEPENDENTLY after the init segment. ---
+	// Parsing init+oneSegment in isolation mirrors exactly what hls.js does with
+	// an #EXT-X-MAP init and a single media part.
+	var totalSamples, totalSync int
+	wantTFDT := []uint64{0, 2000, 4000}
+	for i, s := range segments {
+		standalone := append(append([]byte(nil), initBytes...), s.Data...)
+		parsed, err := mp4ff.DecodeFile(bytes.NewReader(standalone))
+		if err != nil {
+			t.Fatalf("segment %d: decode init+segment: %v", i, err)
+		}
+		if len(parsed.Segments) != 1 {
+			t.Fatalf("segment %d: parsed %d media segments, want 1", i, len(parsed.Segments))
+		}
+		mseg := parsed.Segments[0]
+		if mseg.Styp == nil {
+			t.Errorf("segment %d: missing CMAF styp box", i)
+		}
+		if len(mseg.Fragments) != 1 {
+			t.Fatalf("segment %d: %d fragments, want 1", i, len(mseg.Fragments))
+		}
+		fr := mseg.Fragments[0]
+		if got := fr.Moof.Mfhd.SequenceNumber; got != s.SequenceNumber {
+			t.Errorf("segment %d: moof sequence=%d, want %d", i, got, s.SequenceNumber)
+		}
+		traf := fr.Moof.Traf
+		if traf.Tfhd.TrackID != 1 {
+			t.Errorf("segment %d: track id=%d, want 1", i, traf.Tfhd.TrackID)
+		}
+		if got := traf.Tfdt.BaseMediaDecodeTime(); got != wantTFDT[i] {
+			t.Errorf("segment %d: tfdt baseMediaDecodeTime=%d, want %d", i, got, wantTFDT[i])
+		}
+
+		var samples []mp4ff.Sample
+		for _, trun := range traf.Truns {
+			samples = append(samples, trun.Samples...)
+		}
+		if len(samples) == 0 {
+			t.Fatalf("segment %d: no samples", i)
+		}
+		if !isSyncSample(samples[0]) {
+			t.Errorf("segment %d: first sample is not a keyframe/sync sample", i)
+		}
+		var segDur uint64
+		for j, smp := range samples {
+			totalSamples++
+			if isSyncSample(smp) {
+				totalSync++
+			}
+			segDur += uint64(smp.Dur)
+			if smp.Size == 0 {
+				t.Errorf("segment %d sample %d: zero size", i, j)
+			}
+		}
+		if segDur != s.DurationMs {
+			t.Errorf("segment %d: summed sample dur=%d, reported DurationMs=%d", i, segDur, s.DurationMs)
+		}
+	}
+
+	if totalSamples != numFrames {
+		t.Errorf("total samples across segments=%d, want %d", totalSamples, numFrames)
+	}
+	if totalSync != numGOPs {
+		t.Errorf("total sync samples=%d, want %d (one per GOP)", totalSync, numGOPs)
+	}
+}
+
+// TestLiveSegmenterDropsLeadingNonKeyframe verifies a session cannot open on a
+// non-IDR frame (which would reference frames that never arrived); such leading
+// samples are dropped until the first keyframe.
+func TestLiveSegmenterDropsLeadingNonKeyframe(t *testing.T) {
+	seg := NewLiveSegmenter("H264", [][]byte{liveTestSPS}, [][]byte{liveTestPPS}, nil, 1000)
+	seg.SetDimensions(640, 480)
+	var segments []LiveSegment
+	seg.OnSegment = func(s LiveSegment) error { segments = append(segments, s); return nil }
+
+	// Two P-frames before any IDR must be ignored.
+	if err := seg.WriteSample(false, makeAnnexBFrame(false), 0, 0); err != nil {
+		t.Fatalf("WriteSample(p0): %v", err)
+	}
+	if err := seg.WriteSample(false, makeAnnexBFrame(false), 40, 0); err != nil {
+		t.Fatalf("WriteSample(p1): %v", err)
+	}
+	// First IDR opens the session at decode time 0.
+	for i := 0; i < 25; i++ {
+		isKey := i == 0
+		if err := seg.WriteSample(isKey, makeAnnexBFrame(isKey), uint64(i)*40, 0); err != nil {
+			t.Fatalf("WriteSample(%d): %v", i, err)
+		}
+	}
+	if err := seg.Close(); err != nil {
+		t.Fatalf("Close: %v", err)
+	}
+
+	if len(segments) == 0 {
+		t.Fatal("expected at least one segment after the first IDR")
+	}
+	initBytes, err := seg.InitSegment()
+	if err != nil {
+		t.Fatalf("InitSegment: %v", err)
+	}
+	standalone := append(append([]byte(nil), initBytes...), segments[0].Data...)
+	parsed, err := mp4ff.DecodeFile(bytes.NewReader(standalone))
+	if err != nil {
+		t.Fatalf("decode: %v", err)
+	}
+	traf := parsed.Segments[0].Fragments[0].Moof.Traf
+	if got := traf.Tfdt.BaseMediaDecodeTime(); got != 0 {
+		t.Errorf("first segment tfdt=%d, want 0 (session opens on the IDR)", got)
+	}
+	var first mp4ff.Sample
+	for _, trun := range traf.Truns {
+		if len(trun.Samples) > 0 {
+			first = trun.Samples[0]
+			break
+		}
+	}
+	if !isSyncSample(first) {
+		t.Error("first committed sample must be the IDR, not a dropped P-frame")
+	}
+}
+
+// renderLiveMediaPlaylist renders a live (no #EXT-X-ENDLIST) fMP4 HLS media
+// playlist for the given segments. This mirrors the shape hub-api will serve for
+// live streams: an #EXT-X-MAP init segment followed by one #EXTINF per CMAF part.
+// In production hub-api emits a sliding WINDOW of the most recent segments and
+// advances #EXT-X-MEDIA-SEQUENCE; here we list the whole synthetic capture for a
+// self-contained, inspectable bundle.
+func renderLiveMediaPlaylist(initURI string, segs []LiveSegment, mediaSequence uint32) string {
+	var maxDurMs uint64
+	for _, s := range segs {
+		if s.DurationMs > maxDurMs {
+			maxDurMs = s.DurationMs
+		}
+	}
+	target := uint64(math.Ceil(float64(maxDurMs) / 1000.0))
+	if target == 0 {
+		target = 1
+	}
+
+	var b strings.Builder
+	b.WriteString("#EXTM3U\n")
+	b.WriteString("#EXT-X-VERSION:7\n")
+	fmt.Fprintf(&b, "#EXT-X-TARGETDURATION:%d\n", target)
+	fmt.Fprintf(&b, "#EXT-X-MEDIA-SEQUENCE:%d\n", mediaSequence)
+	b.WriteString("#EXT-X-INDEPENDENT-SEGMENTS\n")
+	fmt.Fprintf(&b, "#EXT-X-MAP:URI=%q\n", initURI)
+	for _, s := range segs {
+		fmt.Fprintf(&b, "#EXTINF:%.3f,\n", float64(s.DurationMs)/1000.0)
+		fmt.Fprintf(&b, "seg-%d.m4s\n", s.SequenceNumber)
+	}
+	// NOTE: deliberately no #EXT-X-ENDLIST - its absence is what marks the
+	// playlist as live so hls.js keeps polling for new segments.
+	return b.String()
+}
+
+// TestLiveSegmenterWritesHLSBundle runs the segmenter over a synthetic stream and
+// writes a complete on-disk fMP4 HLS bundle (init.mp4 + seg-N.m4s + a live
+// stream.m3u8). It validates the playlist shape and that every referenced file
+// exists, then logs the output directory so the structure can be eyeballed.
+//
+// Set LIVEHLS_OUT=/some/dir to keep the bundle for manual inspection (e.g. serve
+// it and point hls.js at stream.m3u8); otherwise a temp dir is used and removed.
+//
+// The frames here are synthetic (valid fMP4 boxing, non-decodable payloads), so
+// this validates CONTAINER/playlist structure, not pixel decode - the round-trip
+// assertions in TestLiveSegmenterProducesIndependentCMAFSegments cover decodable
+// box layout.
+func TestLiveSegmenterWritesHLSBundle(t *testing.T) {
+	const (
+		frameDurMs = uint64(40)
+		gopFrames  = 25
+		numGOPs    = 6
+		numFrames  = gopFrames * numGOPs
+		targetMs   = uint64(2000)
+	)
+
+	outDir := os.Getenv("LIVEHLS_OUT")
+	if outDir == "" {
+		outDir = t.TempDir()
+	} else {
+		if err := os.MkdirAll(outDir, 0o755); err != nil {
+			t.Fatalf("mkdir %s: %v", outDir, err)
+		}
+	}
+
+	seg := NewLiveSegmenter("H264", [][]byte{liveTestSPS}, [][]byte{liveTestPPS}, nil, targetMs)
+	seg.SetDimensions(640, 480)
+
+	var segments []LiveSegment
+	seg.OnInit = func(b []byte) error {
+		return os.WriteFile(filepath.Join(outDir, "init.mp4"), b, 0o644)
+	}
+	seg.OnSegment = func(s LiveSegment) error {
+		segments = append(segments, s)
+		name := fmt.Sprintf("seg-%d.m4s", s.SequenceNumber)
+		return os.WriteFile(filepath.Join(outDir, name), s.Data, 0o644)
+	}
+
+	for i := 0; i < numFrames; i++ {
+		isKey := i%gopFrames == 0
+		if err := seg.WriteSample(isKey, makeAnnexBFrame(isKey), uint64(i)*frameDurMs, 0); err != nil {
+			t.Fatalf("WriteSample(%d): %v", i, err)
+		}
+	}
+	if err := seg.Close(); err != nil {
+		t.Fatalf("Close: %v", err)
+	}
+	if len(segments) == 0 {
+		t.Fatal("no segments produced")
+	}
+
+	playlist := renderLiveMediaPlaylist("init.mp4", segments, segments[0].SequenceNumber)
+	if err := os.WriteFile(filepath.Join(outDir, "stream.m3u8"), []byte(playlist), 0o644); err != nil {
+		t.Fatalf("write playlist: %v", err)
+	}
+
+	// --- Validate the live playlist shape. ---
+	mustContain := []string{
+		"#EXTM3U",
+		"#EXT-X-VERSION:7",
+		"#EXT-X-TARGETDURATION:2",
+		"#EXT-X-MEDIA-SEQUENCE:1",
+		`#EXT-X-MAP:URI="init.mp4"`,
+		"#EXT-X-INDEPENDENT-SEGMENTS",
+	}
+	for _, tag := range mustContain {
+		if !strings.Contains(playlist, tag) {
+			t.Errorf("playlist missing %q\n---\n%s", tag, playlist)
+		}
+	}
+	if strings.Contains(playlist, "#EXT-X-ENDLIST") {
+		t.Error("live playlist must NOT contain #EXT-X-ENDLIST")
+	}
+	if got, want := strings.Count(playlist, "#EXTINF:"), len(segments); got != want {
+		t.Errorf("playlist has %d #EXTINF entries, want %d", got, want)
+	}
+
+	// --- Every referenced file must exist on disk. ---
+	if _, err := os.Stat(filepath.Join(outDir, "init.mp4")); err != nil {
+		t.Errorf("init.mp4 missing: %v", err)
+	}
+	for _, s := range segments {
+		name := fmt.Sprintf("seg-%d.m4s", s.SequenceNumber)
+		if _, err := os.Stat(filepath.Join(outDir, name)); err != nil {
+			t.Errorf("%s missing: %v", name, err)
+		}
+	}
+
+	t.Logf("wrote HLS bundle to %s (%d segments)\n%s", outDir, len(segments), playlist)
+}
+
+// boxTypeAt returns the 4CC box type at the front of a top-level box blob (the
+// 4 bytes following the 32-bit size), or "" if the blob is too short.
+func boxTypeAt(b []byte) string {
+	if len(b) < 8 {
+		return ""
+	}
+	return string(b[4:8])
+}
+
+// TestLiveSegmenterLowLatencyParts runs the segmenter in LL-HLS mode over the
+// same synthetic stream and asserts that:
+//   - each ~2s segment is sliced into multiple CMAF parts (more parts than
+//     segments overall);
+//   - part 0 of every segment carries the CMAF styp and is INDEPENDENT (begins
+//     with the segment keyframe); later parts are bare moof+mdat (no styp);
+//   - moof sequence numbers are globally monotonic across all parts (MSE needs
+//     increasing moof sequence numbers);
+//   - concatenating a segment's parts in order yields exactly the same bytes the
+//     classic per-segment path would emit, decoding into one independent CMAF
+//     segment whose first sample is a sync sample with the expected tfdt;
+//   - every sample and keyframe of the input is preserved end to end.
+func TestLiveSegmenterLowLatencyParts(t *testing.T) {
+	const (
+		frameDurMs = uint64(40) // 25 fps
+		gopFrames  = 25         // keyframe every 1000 ms
+		numGOPs    = 6
+		numFrames  = gopFrames * numGOPs // 150 frames, 6000 ms
+		targetMs   = uint64(2000)        // 2s segments => 2 GOPs each
+		partMs     = uint64(300)         // ~300 ms parts => ~6-7 parts/segment
+	)
+
+	seg := NewLiveSegmenter("H264", [][]byte{liveTestSPS}, [][]byte{liveTestPPS}, nil, targetMs)
+	seg.SetDimensions(640, 480)
+	seg.EnableLowLatency(partMs)
+
+	var initBytes []byte
+	var initCalls int
+	var parts []LivePart
+	seg.OnInit = func(b []byte) error {
+		initCalls++
+		initBytes = append([]byte(nil), b...)
+		return nil
+	}
+	seg.OnPart = func(p LivePart) error {
+		parts = append(parts, p)
+		return nil
+	}
+
+	for i := 0; i < numFrames; i++ {
+		isKey := i%gopFrames == 0
+		if err := seg.WriteSample(isKey, makeAnnexBFrame(isKey), uint64(i)*frameDurMs, 0); err != nil {
+			t.Fatalf("WriteSample(frame=%d): %v", i, err)
+		}
+	}
+	if err := seg.Close(); err != nil {
+		t.Fatalf("Close: %v", err)
+	}
+
+	if initCalls != 1 {
+		t.Fatalf("OnInit called %d times, want 1", initCalls)
+	}
+	if len(parts) == 0 {
+		t.Fatal("no parts produced in low-latency mode")
+	}
+
+	// --- Parts are globally moof-monotonic, and group into 3 segments whose part
+	// indices are contiguous from 0. ---
+	bySeg := map[uint32][]LivePart{}
+	var order []uint32
+	var lastMoof uint32
+	for i, p := range parts {
+		if _, seen := bySeg[p.SegmentSeq]; !seen {
+			order = append(order, p.SegmentSeq)
+		}
+		bySeg[p.SegmentSeq] = append(bySeg[p.SegmentSeq], p)
+
+		// Decode the part to read its moof sequence number and confirm the styp
+		// convention (part 0 => styp present, later parts => bare moof+mdat).
+		front := boxTypeAt(p.Data)
+		if p.PartIndex == 0 {
+			if front != "styp" {
+				t.Errorf("seg %d part 0: leading box=%q, want styp", p.SegmentSeq, front)
+			}
+			if !p.Independent {
+				t.Errorf("seg %d part 0: Independent=false, want true (starts on keyframe)", p.SegmentSeq)
+			}
+		} else if front != "moof" {
+			t.Errorf("seg %d part %d: leading box=%q, want moof (no styp on later parts)", p.SegmentSeq, p.PartIndex, front)
+		}
+
+		parsed, err := mp4ff.DecodeFile(bytes.NewReader(p.Data))
+		if err != nil {
+			t.Fatalf("seg %d part %d: decode: %v", p.SegmentSeq, p.PartIndex, err)
+		}
+		if len(parsed.Segments) != 1 || len(parsed.Segments[0].Fragments) != 1 {
+			t.Fatalf("seg %d part %d: want exactly one fragment", p.SegmentSeq, p.PartIndex)
+		}
+		moof := parsed.Segments[0].Fragments[0].Moof.Mfhd.SequenceNumber
+		if i > 0 && moof <= lastMoof {
+			t.Errorf("part %d: moof sequence=%d not greater than previous %d", i, moof, lastMoof)
+		}
+		lastMoof = moof
+	}
+
+	if len(order) != 3 {
+		t.Fatalf("got %d segments, want 3", len(order))
+	}
+	if len(parts) <= len(order) {
+		t.Fatalf("got %d parts for %d segments, expected each segment to be sliced into multiple parts", len(parts), len(order))
+	}
+	for _, segSeq := range order {
+		for idx, p := range bySeg[segSeq] {
+			if p.PartIndex != uint32(idx) {
+				t.Errorf("seg %d: part index %d out of order (want %d)", segSeq, p.PartIndex, idx)
+			}
+		}
+	}
+
+	// --- Concatenating a segment's parts must reconstruct one independent CMAF
+	// segment that decodes against the init segment. ---
+	wantTFDT := map[uint32]uint64{1: 0, 2: 2000, 3: 4000}
+	var totalSamples, totalSync int
+	for _, segSeq := range order {
+		segParts := bySeg[segSeq]
+		var full []byte
+		var wantPartDur uint64
+		for _, p := range segParts {
+			full = append(full, p.Data...)
+			wantPartDur += p.DurationMs
+		}
+		standalone := append(append([]byte(nil), initBytes...), full...)
+		parsed, err := mp4ff.DecodeFile(bytes.NewReader(standalone))
+		if err != nil {
+			t.Fatalf("seg %d: decode concatenated parts: %v", segSeq, err)
+		}
+		if len(parsed.Segments) != 1 {
+			t.Fatalf("seg %d: parsed %d media segments, want 1", segSeq, len(parsed.Segments))
+		}
+		mseg := parsed.Segments[0]
+		if mseg.Styp == nil {
+			t.Errorf("seg %d: reconstructed segment missing CMAF styp", segSeq)
+		}
+		if len(mseg.Fragments) != len(segParts) {
+			t.Errorf("seg %d: %d fragments, want %d (one per part)", segSeq, len(mseg.Fragments), len(segParts))
+		}
+		firstTraf := mseg.Fragments[0].Moof.Traf
+		if got := firstTraf.Tfdt.BaseMediaDecodeTime(); got != wantTFDT[segSeq] {
+			t.Errorf("seg %d: first fragment tfdt=%d, want %d", segSeq, got, wantTFDT[segSeq])
+		}
+		var segDur uint64
+		var firstSample mp4ff.Sample
+		var haveFirst bool
+		for _, fr := range mseg.Fragments {
+			for _, trun := range fr.Moof.Traf.Truns {
+				for _, smp := range trun.Samples {
+					if !haveFirst {
+						firstSample = smp
+						haveFirst = true
+					}
+					totalSamples++
+					if isSyncSample(smp) {
+						totalSync++
+					}
+					segDur += uint64(smp.Dur)
+				}
+			}
+		}
+		if !isSyncSample(firstSample) {
+			t.Errorf("seg %d: first sample is not a sync sample", segSeq)
+		}
+		if segDur != wantPartDur {
+			t.Errorf("seg %d: summed sample dur=%d, summed part dur=%d", segSeq, segDur, wantPartDur)
+		}
+	}
+
+	if totalSamples != numFrames {
+		t.Errorf("total samples across parts=%d, want %d", totalSamples, numFrames)
+	}
+	if totalSync != numGOPs {
+		t.Errorf("total sync samples=%d, want %d (one per GOP)", totalSync, numGOPs)
+	}
+}
+

machinery/src/video/mp4.go

@@ -32,14 +32,20 @@ const MacEpochOffset uint64 = 2082844800
 // resulting in ~3 second fragments (assuming a typical GOP interval).
 const FragmentDurationMs = 3000
 
-// MinNormalGOPMs is the minimum spacing we expect between two consecutive
-// IDRs of a healthy source (typical encoders produce IDRs every 1000ms or
-// more). When two keyframes arrive closer than this, we treat the second one
-// as an upstream restart/loop-seam and force a fresh fragment so the seam
-// IDR cannot end up as a mid-fragment sync sample. The check only runs when
-// the current fragment has not yet reached FragmentDurationMs, so it never
-// fires during normal multi-GOP fragments at intended GOP boundaries.
-const MinNormalGOPMs = 950
+// SeamGapDivisor controls loop-seam detection. A keyframe is treated as an
+// upstream loop/restart seam when it arrives in less than (smallest normal
+// keyframe interval / SeamGapDivisor) — i.e. far sooner than the camera's
+// tightest established keyframe cadence.
+//
+// The reference is the running *minimum* keyframe interval, NOT the immediately
+// preceding one. Variable-GOP ("smart codec") cameras lengthen the GOP during
+// static scenes and shorten it again on motion, so consecutive intervals differ
+// wildly (e.g. 2000 ms then 500 ms). Comparing against the previous interval
+// then flags every normal short GOP that happens to follow a long static GOP as
+// a seam and drops healthy video. Comparing against the minimum cadence instead
+// scales with any configured GOP size (0.5s, 1s, 2s, ...) yet never mistakes the
+// camera's own normal cadence for a premature seam IDR.
+const SeamGapDivisor = 2
 
 type MP4 struct {
 	// FileName is the name of the file
@@ -65,7 +71,6 @@ type MP4 struct {
 	FreeBoxSize             int64
 	FragmentStartRawPTS     uint64            // Raw PTS for timing when to flush fragments
 	FragmentStartDTS        uint64            // Accumulated VideoTotalDuration at fragment start (matches tfdt)
-	LastKeyframeRawPTS      uint64            // Raw PTS of the most recently seen keyframe (in any fragment)
 	MoofBoxes               int64             // Number of moof boxes in the file
 	MoofBoxSizes            []int64           // Sizes of each moof box
 	SegmentDurations        []uint64          // Duration of each segment in timescale units
@@ -84,6 +89,21 @@ type MP4 struct {
 	TotalKeyframesWritten   int               // Total keyframes written to trun boxes
 	FragmentKeyframeCount   int               // Keyframes in the current fragment
 	PendingSampleIsKeyframe bool              // Whether the pending video sample is a keyframe
+	LastKeyframeRawPTS      uint64            // Raw PTS of the most recently seen keyframe (across fragments)
+	LastKeyframeGapMs       uint64            // Interval (ms) between the two most recent keyframes (diagnostic only)
+	MinKeyframeGapMs        uint64            // Smallest keyframe interval (ms) seen so far; the camera's tightest cadence and the reference for seam detection
+	gopBuffer               []bufferedSample  // Current, not-yet-committed GOP (video frames + interleaved audio), held so a loop-seam GOP can be dropped before it reaches the file
+}
+
+// bufferedSample is a single sample (video or audio) held in the current-GOP
+// buffer until we know whether the GOP should be committed to the file or
+// dropped as an upstream loop-seam artifact (see AddSampleToTrack).
+type bufferedSample struct {
+	trackID           uint32
+	isKeyframe        bool
+	data              []byte
+	pts               uint64
+	compositionOffset int64
 }
 
 // NewMP4 creates a new MP4 object.
@@ -243,24 +263,6 @@ func (mp4 *MP4) flushPendingVideoSample(nextPTS uint64) bool {
 	var duration uint64
 	if nextPTS > 0 && nextPTS > mp4.VideoFullSample.DecodeTime {
 		duration = nextPTS - mp4.VideoFullSample.DecodeTime
-		// Guard against forward PTS jumps (e.g. when looping a source MP4
-		// through virtual-rtsp the upstream ffmpeg may insert a large offset
-		// at the loop boundary, or the RTSP stream may stall briefly).
-		// Without this clamp the sample gets a huge duration which appears
-		// as a discontinuity in the trun/sidx/mvhd and causes browsers
-		// (Video.js / MSE) to abort playback with a "media corruption"
-		// error around the loop boundary.
-		var maxPlausible uint64 = 1000 // 1 second hard ceiling
-		if mp4.LastVideoSampleDTS > 0 && mp4.LastVideoSampleDTS*10 < maxPlausible {
-			maxPlausible = mp4.LastVideoSampleDTS * 10
-		}
-		if duration > maxPlausible {
-			log.Log.Warning(fmt.Sprintf("mp4.flushPendingVideoSample(): video PTS jumped forward (nextPTS=%d, prevDTS=%d, gap=%d ms) - clamping to %d ms (likely source loop/stall discontinuity)", nextPTS, mp4.VideoFullSample.DecodeTime, duration, maxPlausible))
-			duration = mp4.LastVideoSampleDTS
-			if duration == 0 {
-				duration = 33
-			}
-		}
 	} else {
 		// No valid nextPTS (Close case) or PTS went backwards (jitter/discontinuity)
 		if nextPTS > 0 {
@@ -294,7 +296,191 @@ func (mp4 *MP4) flushPendingVideoSample(nextPTS uint64) bool {
 	return true
 }
 
-func (mp4 *MP4) AddSampleToTrack(trackID uint32, isKeyframe bool, data []byte, pts uint64) error {
+// AddSampleToTrack appends a sample to the given track.
+//
+// For video, pts is the decode timestamp (DTS, in milliseconds) and
+// compositionOffset is the composition time offset (PTS - DTS, in milliseconds).
+// The offset is non-zero only for streams that contain B-frames; it is written
+// as the sample's signed composition time offset so the decoder presents frames
+// in PTS order while the fragment timeline stays monotonic in DTS.
+//
+// For audio, pts is the sample timestamp and compositionOffset should be 0.
+//
+// Samples are not written straight through. Each video GOP is held in a small
+// buffer (gopBuffer) until the next keyframe arrives, so a GOP belonging to an
+// upstream source-loop / restart seam can be dropped before it ever reaches the
+// file. When a source MP4 is looped through virtual-rtsp
+// (ffmpeg `-stream_loop -1 -re`), the loop boundary leaves a truncated tail GOP
+// whose first inter-frame is incomplete: software decoders conceal the missing
+// macroblocks, but hardware decoders (macOS VideoToolbox) reject it with
+// kVTVideoDecoderBadDataErr (-12909) and MSE players (Video.js / Chromium /
+// Firefox) report media corruption, freezing playback at the seam (e.g. the
+// ~10s mark in the original recordings). The seam IDR that follows is a clean
+// random-access point, so dropping the truncated GOP lets playback continue
+// seamlessly. Holding back at most one GOP only delays on-disk fragments; for
+// any recording without a seam the finalized file is identical to the straight
+// pass-through output (Close flushes the final buffered GOP).
+func (mp4 *MP4) AddSampleToTrack(trackID uint32, isKeyframe bool, data []byte, pts uint64, compositionOffset int64) error {
+	isVideoKeyframe := isKeyframe && trackID == uint32(mp4.VideoTrack)
+	if !isVideoKeyframe {
+		// Part of the current GOP window (P/B frame or interleaved audio): hold it
+		// until the GOP is committed or dropped at the next video keyframe.
+		mp4.gopBuffer = append(mp4.gopBuffer, bufferedSample{
+			trackID:           trackID,
+			isKeyframe:        isKeyframe,
+			data:              data,
+			pts:               pts,
+			compositionOffset: compositionOffset,
+		})
+		return nil
+	}
+
+	// A video keyframe ends the GOP we have been buffering. Decide whether that
+	// buffered GOP is genuine (commit it) or the truncated tail GOP at an upstream
+	// loop/restart seam (drop it).
+	//
+	// A genuine loop/restart seam has TWO signatures that must BOTH hold; we never
+	// drop a GOP on the interval alone, because variable-GOP ("smart codec")
+	// cameras legitimately shorten the GOP on motion:
+	//
+	//  1. The new keyframe arrives much sooner than the camera's tightest normal
+	//     cadence: gap*SeamGapDivisor < MinKeyframeGapMs (the running MINIMUM
+	//     interval). Using the minimum — not the previous interval — means a
+	//     normal short GOP that merely follows a long static GOP (2000 ms -> 500 ms)
+	//     is NOT flagged, while a true premature restart still is.
+	//  2. The GOP we just buffered is actually TRUNCATED — far shorter than a full
+	//     GOP. A real seam cuts a GOP off mid-stream, leaving only a handful of
+	//     frames; a healthy GOP (even a legitimately short one) is left intact and
+	//     must be committed in full. We require the buffered tail to be under half
+	//     the minimum normal GOP length to qualify as truncated.
+	//
+	// Deriving both thresholds from the observed cadence keeps detection correct
+	// for any configured GOP size (0.5s, 1s, 2s, ...) and stops the heuristic from
+	// discarding healthy video.
+	seam := false
+	if mp4.LastKeyframeRawPTS > 0 && pts > mp4.LastKeyframeRawPTS {
+		gap := pts - mp4.LastKeyframeRawPTS
+		bufferedVideo := mp4.bufferedVideoCount()
+		// Frames a full GOP at the tightest normal cadence would contain.
+		fullGopFrames := mp4.expectedGopFrames(gap)
+		closeKeyframe := mp4.MinKeyframeGapMs > 0 && gap*SeamGapDivisor < mp4.MinKeyframeGapMs
+		truncatedTail := fullGopFrames > 0 && bufferedVideo*2 < fullGopFrames
+		if closeKeyframe && truncatedTail {
+			seam = true
+			log.Log.Warning(fmt.Sprintf("mp4.AddSampleToTrack(): dropping truncated GOP at premature keyframe (interval=%d ms, min interval=%d ms, buffered video frames=%d of ~%d) - likely upstream loop/restart discontinuity", gap, mp4.MinKeyframeGapMs, bufferedVideo, fullGopFrames))
+		}
+		mp4.LastKeyframeGapMs = gap
+		if !seam && (mp4.MinKeyframeGapMs == 0 || gap < mp4.MinKeyframeGapMs) {
+			mp4.MinKeyframeGapMs = gap
+		}
+	}
+	mp4.LastKeyframeRawPTS = pts
+
+	if seam {
+		// Discard the truncated tail GOP; this keyframe is a clean restart point.
+		mp4.gopBuffer = mp4.gopBuffer[:0]
+	} else {
+		// Genuine GOP boundary: commit the GOP we just finished buffering.
+		mp4.commitBufferedGOP()
+	}
+
+	// Begin buffering the new GOP, starting with this keyframe.
+	mp4.gopBuffer = append(mp4.gopBuffer, bufferedSample{
+		trackID:           trackID,
+		isKeyframe:        isKeyframe,
+		data:              data,
+		pts:               pts,
+		compositionOffset: compositionOffset,
+	})
+	return nil
+}
+
+// bufferedVideoCount returns how many video-track samples are currently held in
+// the GOP buffer (interleaved audio samples are ignored). It measures how
+// complete the buffered GOP is, used to tell a truncated seam tail from a
+// healthy — possibly legitimately short — GOP.
+func (mp4 *MP4) bufferedVideoCount() uint64 {
+	var n uint64
+	for _, s := range mp4.gopBuffer {
+		if s.trackID == uint32(mp4.VideoTrack) {
+			n++
+		}
+	}
+	return n
+}
+
+// expectedGopFrames estimates how many video frames a full GOP at the camera's
+// tightest normal cadence (MinKeyframeGapMs) would contain, using the video
+// frame interval inferred from the buffered GOP. gap is the current keyframe
+// interval, used as a fallback frame-duration source. Returns 0 when there is
+// not yet enough information to judge (so callers must not treat a GOP as
+// truncated without a reliable estimate).
+func (mp4 *MP4) expectedGopFrames(gap uint64) uint64 {
+	cadence := mp4.MinKeyframeGapMs
+	if cadence == 0 {
+		return 0
+	}
+	frameDur := mp4.bufferedVideoFrameDuration()
+	if frameDur == 0 {
+		// Fall back to deriving a per-frame duration from the buffered tail across
+		// the current interval; if that is unavailable too, we cannot estimate.
+		if n := mp4.bufferedVideoCount(); n > 0 && gap > 0 {
+			frameDur = gap / n
+		}
+	}
+	if frameDur == 0 {
+		return 0
+	}
+	return cadence / frameDur
+}
+
+// bufferedVideoFrameDuration returns the average per-frame duration (in PTS
+// units) of the video samples currently buffered, derived from the PTS deltas
+// between consecutive video frames. Returns 0 when fewer than two video frames
+// are buffered.
+func (mp4 *MP4) bufferedVideoFrameDuration() uint64 {
+	var prev uint64
+	havePrev := false
+	var sum, count uint64
+	for _, s := range mp4.gopBuffer {
+		if s.trackID != uint32(mp4.VideoTrack) {
+			continue
+		}
+		if havePrev && s.pts > prev {
+			sum += s.pts - prev
+			count++
+		}
+		prev = s.pts
+		havePrev = true
+	}
+	if count == 0 {
+		return 0
+	}
+	return sum / count
+}
+
+// commitBufferedGOP writes every sample currently held in gopBuffer to the file
+// in arrival order, then clears the buffer. Committing in arrival order
+// preserves the original audio/video interleave and lets commitSampleToTrack's
+// pending-sample mechanism derive each sample's duration from the next one, so
+// the on-disk result matches a straight pass-through.
+func (mp4 *MP4) commitBufferedGOP() {
+	if len(mp4.gopBuffer) == 0 {
+		return
+	}
+	buffered := mp4.gopBuffer
+	mp4.gopBuffer = nil // detach so commitSampleToTrack never observes a half-cleared buffer
+	for _, s := range buffered {
+		if err := mp4.commitSampleToTrack(s.trackID, s.isKeyframe, s.data, s.pts, s.compositionOffset); err != nil {
+			log.Log.Error("mp4.commitBufferedGOP(): " + err.Error())
+		}
+	}
+}
+
+// commitSampleToTrack appends a single buffered sample to the current fragment.
+// It is the low-level writer behind AddSampleToTrack and is only ever invoked
+// from commitBufferedGOP, after a GOP has been confirmed as non-seam.
+func (mp4 *MP4) commitSampleToTrack(trackID uint32, isKeyframe bool, data []byte, pts uint64, compositionOffset int64) error {
 
 	if isKeyframe && trackID == uint32(mp4.VideoTrack) {
 		mp4.TotalKeyframesReceived++
@@ -317,27 +503,6 @@ func (mp4 *MP4) AddSampleToTrack(trackID uint32, isKeyframe bool, data []byte, p
 		}
 		shouldFlush := !mp4.Start || elapsed >= FragmentDurationMs
 
-		// Detect upstream source-loop / restart discontinuity. When an MP4 is
-		// looped through virtual-rtsp (ffmpeg `-stream_loop -1 -re`) the loop
-		// seam emits a fresh IDR much sooner than a normal GOP would. PTS keeps
-		// growing monotonically, so the timing-only `elapsed` check above does
-		// not catch it and the seam IDR ends up as a mid-fragment sync sample.
-		// MSE-based players (Video.js / Chromium / Firefox) reject the resulting
-		// fragment with a "media corruption" error because the inner IDR resets
-		// frame_num/POC inside what they expect to be a single GOP. Force a
-		// fragment boundary whenever two consecutive keyframes arrive much
-		// closer than a normal GOP (here: < 500 ms apart). This isolates the
-		// seam IDR into its own fragment so each fragment stays a clean GOP.
-		if !shouldFlush && trackID == uint32(mp4.VideoTrack) && mp4.Start &&
-			mp4.LastKeyframeRawPTS > 0 && pts > mp4.LastKeyframeRawPTS &&
-			pts-mp4.LastKeyframeRawPTS < MinNormalGOPMs {
-			log.Log.Warning(fmt.Sprintf("mp4.AddSampleToTrack(): forcing fragment flush at unexpectedly close keyframe (gap=%d ms, fragment elapsed=%d ms) - likely upstream loop/restart discontinuity", pts-mp4.LastKeyframeRawPTS, elapsed))
-			shouldFlush = true
-		}
-		if trackID == uint32(mp4.VideoTrack) {
-			mp4.LastKeyframeRawPTS = pts
-		}
-
 		if shouldFlush {
 			// Write the previous segment to the file
 			if mp4.Start {
@@ -424,7 +589,7 @@ func (mp4 *MP4) AddSampleToTrack(trackID uint32, isKeyframe bool, data []byte, p
 				fullSample.Sample = mp4ff.Sample{
 					Size:                  uint32(len(fullSample.Data)),
 					Flags:                 flags,
-					CompositionTimeOffset: 0, // No composition time offset for video
+					CompositionTimeOffset: int32(compositionOffset), // PTS-DTS, non-zero for B-frames
 				}
 				mp4.VideoFullSample = &fullSample
 				mp4.PendingSampleIsKeyframe = isKeyframe
@@ -442,14 +607,6 @@ func (mp4 *MP4) AddSampleToTrack(trackID uint32, isKeyframe bool, data []byte, p
 					if started {
 						dts = 1
 					}
-					// Guard against forward PTS jumps (e.g. virtual-rtsp loop
-					// boundary or upstream stalls). Without this clamp the
-					// audio trun would carry an enormous sample duration that
-					// renders the recording unplayable in browsers.
-					if mp4.LastAudioSampleDTS > 0 && dts > mp4.LastAudioSampleDTS*10 {
-						log.Log.Warning(fmt.Sprintf("mp4.AddSampleToTrack(): audio PTS jumped forward (pts=%d, prevDTS=%d, gap=%d) - clamping to last known duration", pts, mp4.AudioFullSample.DecodeTime, dts))
-						dts = mp4.LastAudioSampleDTS
-					}
 					mp4.LastAudioSampleDTS = dts
 					//fmt.Printf("Adding sample to track %d, PTS: %d, Duration: %d, size: %d\n", trackID, pts, dts, len(aac[7:]))
 					mp4.AudioTotalDuration += dts
@@ -485,6 +642,10 @@ func (mp4 *MP4) AddSampleToTrack(trackID uint32, isKeyframe bool, data []byte, p
 
 func (mp4 *MP4) Close(config *models.Config) {
 
+	// Commit the final buffered GOP held back for seam detection. The last GOP of
+	// a recording is never a loop seam, so it must always be written out.
+	mp4.commitBufferedGOP()
+
 	log.Log.Info(fmt.Sprintf("mp4.Close(): KEYFRAME SUMMARY - totalReceived=%d, totalWritten=%d, segments=%d, lastFragmentKF=%d",
 		mp4.TotalKeyframesReceived, mp4.TotalKeyframesWritten, mp4.SegmentCount, mp4.FragmentKeyframeCount))
 
@@ -619,6 +780,13 @@ func (mp4 *MP4) Close(config *models.Config) {
 		includePS := true
 		spsNALUs, ppsNALUs := normalizeH264ParameterSets(mp4.SPSNALUs, mp4.PPSNALUs)
 		log.Log.Debug("mp4.Close(): AVC parameter sets: SPS=" + formatNaluDebug(spsNALUs) + ", PPS=" + formatNaluDebug(ppsNALUs))
+		if len(spsNALUs) == 0 || len(ppsNALUs) == 0 {
+			// An avcC without both SPS and PPS is invalid: downstream FFmpeg-based
+			// pipelines decoding this file will report "non-existing PPS 0 referenced"
+			// and fail to extract any frame. Surface it loudly so the capture-side
+			// parameter-set handling can be diagnosed.
+			log.Log.Error(fmt.Sprintf("mp4.Close(): incomplete H264 parameter sets (SPS=%d, PPS=%d) - the avcC will be invalid and downstream decoders will report 'non-existing PPS 0 referenced'", len(spsNALUs), len(ppsNALUs)))
+		}
 		err := init.Moov.Traks[0].SetAVCDescriptor("avc1", spsNALUs, ppsNALUs, includePS)
 		if err != nil {
 			log.Log.Error("mp4.Close(): error setting AVC descriptor: " + err.Error())
@@ -645,6 +813,11 @@ func (mp4 *MP4) Close(config *models.Config) {
 		includePS := true
 		vpsNALUs, spsNALUs, ppsNALUs := normalizeH265ParameterSets(mp4.VPSNALUs, mp4.SPSNALUs, mp4.PPSNALUs)
 		log.Log.Debug("mp4.Close(): HEVC parameter sets: VPS=" + formatNaluDebug(vpsNALUs) + ", SPS=" + formatNaluDebug(spsNALUs) + ", PPS=" + formatNaluDebug(ppsNALUs))
+		if len(vpsNALUs) == 0 || len(spsNALUs) == 0 || len(ppsNALUs) == 0 {
+			// An hvcC missing VPS/SPS/PPS is invalid and downstream FFmpeg-based
+			// pipelines will fail to decode the recording. Surface it loudly.
+			log.Log.Error(fmt.Sprintf("mp4.Close(): incomplete H265 parameter sets (VPS=%d, SPS=%d, PPS=%d) - the hvcC will be invalid and downstream decoders will fail to process the recording", len(vpsNALUs), len(spsNALUs), len(ppsNALUs)))
+		}
 		err := init.Moov.Traks[0].SetHEVCDescriptor("hvc1", vpsNALUs, spsNALUs, ppsNALUs, [][]byte{}, includePS)
 		if err != nil {
 			log.Log.Error("mp4.Close(): error setting HEVC descriptor: " + err.Error())

machinery/src/video/mp4_duration_test.go

@@ -49,7 +49,7 @@ func TestMP4Duration(t *testing.T) {
 	for i := 0; i < numFrames; i++ {
 		pts := uint64(i) * frameDuration
 		isKeyframe := i%gopSize == 0
-		err := mp4Video.AddSampleToTrack(videoTrack, isKeyframe, makeFrame(isKeyframe), pts)
+		err := mp4Video.AddSampleToTrack(videoTrack, isKeyframe, makeFrame(isKeyframe), pts, 0)
 		if err != nil {
 			t.Fatalf("AddSampleToTrack failed at frame %d: %v", i, err)
 		}

machinery/src/video/mp4_loopseam_test.go

@@ -1,7 +1,6 @@
 package video
 
 import (
-	"fmt"
 	"os"
 	"testing"
 
@@ -9,20 +8,39 @@ import (
 	"github.com/kerberos-io/agent/machinery/src/models"
 )
 
-// TestMP4LoopSeamIsolation reproduces the loop-seam pattern from the
-// failing virtual-rtsp recordings: ~1s GOPs, but at the source-MP4
-// loop boundary an IDR arrives prematurely (~200-870ms after the
-// previous IDR). Without the fix this seam IDR ends up bunched into
-// the same fragment as the prior GOP's IDR which trips macOS
-// VideoToolbox (kVTVideoDecoderBadDataErr / -12909). The fix forces
-// a fragment flush whenever two IDRs arrive closer than MinNormalGOPMs.
-func TestMP4LoopSeamIsolation(t *testing.T) {
-	tmpFile := "/tmp/test_loop_seam.mp4"
-	defer os.Remove(tmpFile)
+// runLoopSeamScenario builds a fragmented MP4 that reproduces the loop-seam
+// pattern observed in the failing virtual-rtsp recordings (e.g.
+// thales_1781196512_3-138_2top_0-0-0-0_-1_30219.mp4): a steady GOP cadence, but
+// at the source-MP4 loop boundary the source restarts and emits a fresh IDR far
+// sooner than a normal GOP. In the real recordings the short tail GOP left just
+// before that premature IDR contains a truncated inter-frame - software decoders
+// conceal the missing macroblocks, but hardware decoders (macOS VideoToolbox,
+// kVTVideoDecoderBadDataErr / -12909) and MSE players reject it and freeze
+// playback at the seam (~10s in the original file).
+//
+// The fix detects the premature seam IDR and drops the truncated tail GOP that
+// precedes it. The seam IDR is itself a clean random-access point, so playback
+// resumes seamlessly. This scenario asserts that the tail GOP is removed -
+// exactly one GOP fewer than emitted - while every healthy GOP is preserved in
+// full and no two IDRs are left bunched in a fragment.
+//
+// gopFrames is the number of frames per GOP, so the same scenario can be
+// exercised at different (configurable) camera GOP sizes. The fix derives its
+// threshold from the observed keyframe cadence, so the truncated tail GOP is
+// dropped regardless of GOP size.
+func runLoopSeamScenario(t *testing.T, gopFrames int) {
+	t.Helper()
+
+	tmpFile, err := os.CreateTemp("", "test_loop_seam_*.mp4")
+	if err != nil {
+		t.Fatalf("create temp: %v", err)
+	}
+	tmpFile.Close()
+	defer os.Remove(tmpFile.Name())
 
 	sps := []byte{0x67, 0x42, 0xc0, 0x1e, 0xd9, 0x00, 0xa0, 0x47, 0xfe, 0xc8}
 	pps := []byte{0x68, 0xce, 0x38, 0x80}
-	mp4Video := NewMP4(tmpFile, [][]byte{sps}, [][]byte{pps}, nil, 30)
+	mp4Video := NewMP4(tmpFile.Name(), [][]byte{sps}, [][]byte{pps}, nil, 60)
 	mp4Video.SetWidth(1920)
 	mp4Video.SetHeight(1080)
 	v := mp4Video.AddVideoTrack("H264")
@@ -40,30 +58,77 @@ func TestMP4LoopSeamIsolation(t *testing.T) {
 	}
 
 	frameDur := uint64(33)
+	normalGOPms := uint64(gopFrames) * frameDur
 	pts := uint64(0)
-	emit := func(n int, gopLen int) {
-		for f := 0; f < n; f++ {
-			isKey := (f % gopLen) == 0
-			mp4Video.AddSampleToTrack(v, isKey, mk(isKey), pts)
-			pts += frameDur
+	emitFrame := func(isKey bool) {
+		// compositionOffset is 0: synthetic stream has no B-frames.
+		mp4Video.AddSampleToTrack(v, isKey, mk(isKey), pts, 0)
+		pts += frameDur
+	}
+	emitP := func(n int) {
+		for i := 0; i < n; i++ {
+			emitFrame(false)
 		}
 	}
+	// emitGOP emits one GOP: a leading keyframe followed by gopFrames-1 P-frames.
+	emitGOP := func() {
+		emitFrame(true)
+		emitP(gopFrames - 1)
+	}
 
-	// 17 seconds of normal content (last "good" IDR at sec 17).
-	emit(17*30, 30)
-	// Seam: IDR arrives ~867ms after previous (vs normal 1000ms).
-	pts -= 100
-	emit(13*30, 30)
+	// Several healthy GOPs to establish the cadence and fill a couple of
+	// fragments, then the truncated tail GOP: a keyframe followed by only a few
+	// P-frames before the source loops. This is the GOP that must be dropped.
+	for g := 0; g < 9; g++ {
+		emitGOP()
+	}
+	emitFrame(true)
+	seamLead := gopFrames / 5 // tail GOP is only ~20% of a normal GOP before the loop
+	if seamLead < 1 {
+		seamLead = 1
+	}
+	emitP(seamLead)
+	// Loop seam: the source recording restarts, emitting a fresh IDR far sooner
+	// than the normal GOP. The short tail GOP emitted just above is the truncated
+	// one that must be dropped; this seam IDR opens a fresh, healthy GOP.
+	emitFrame(true)
+	emitP(gopFrames - 1)
+	// The recording continues with normal GOPs to the end.
+	for g := 0; g < 10; g++ {
+		emitGOP()
+	}
 
 	mp4Video.Close(&models.Config{Signing: &models.Signing{PrivateKey: ""}})
 
-	f, _ := os.Open(tmpFile)
+	f, err := os.Open(tmpFile.Name())
+	if err != nil {
+		t.Fatalf("open: %v", err)
+	}
 	defer f.Close()
 	parsed, err := mp4ff.DecodeFile(f)
 	if err != nil {
 		t.Fatalf("decode: %v", err)
 	}
 
+	// After the fix, the truncated tail GOP that precedes the premature seam IDR
+	// is dropped entirely (its first inter-frame is the incomplete one that
+	// freezes hardware decoders), while every other GOP is preserved in full.
+	//
+	// 9 lead GOPs + the seam's own (healthy) GOP + 10 trailing GOPs = 20 committed
+	// GOPs. The standalone "tail" keyframe and its seamLead P-frames are the
+	// dropped truncated GOP, so the output must contain exactly one GOP fewer than
+	// emitted and a whole number of complete GOPs.
+	const committedGOPs = 9 + 1 + 10
+	wantSync := committedGOPs
+	wantSamples := committedGOPs * gopFrames
+
+	// A healthy fragment only ever contains keyframes spaced ~normalGOPms apart.
+	// If any fragment contains two keyframes closer than half a normal GOP, the
+	// premature seam IDR was not dropped and the file will freeze on playback.
+	maxBunchMs := normalGOPms / 2
+
+	totalSamples := 0
+	totalSync := 0
 	fragIdx := 0
 	for _, seg := range parsed.Segments {
 		for _, fr := range seg.Fragments {
@@ -76,24 +141,54 @@ func TestMP4LoopSeamIsolation(t *testing.T) {
 				var keys []uint64
 				for _, trun := range traf.Truns {
 					for _, s := range trun.Samples {
+						totalSamples++
+						// sample_depends_on == 2 => "does not depend on others" => IDR/sync.
 						if (s.Flags>>24)&0x03 == 0x02 {
 							keys = append(keys, offset)
+							totalSync++
 						}
 						offset += uint64(s.Dur)
 					}
 				}
-				fmt.Printf("frag %d tfdt=%d samples_dur=%d keys@%v\n",
-					fragIdx, tfdt, offset, keys)
+				t.Logf("gop=%dframes frag %d tfdt=%d samples_dur=%d keys@%v", gopFrames, fragIdx, tfdt, offset, keys)
 				for i := 1; i < len(keys); i++ {
 					gap := keys[i] - keys[i-1]
-					if gap < MinNormalGOPMs {
-						t.Errorf("frag %d (tfdt=%d): two IDRs only %d ms apart "+
-							"in same fragment (< %d) - seam was not isolated",
-							fragIdx, tfdt, gap, MinNormalGOPMs)
+					if gap < maxBunchMs {
+						t.Errorf("gop=%dframes frag %d (tfdt=%d): two IDRs only %d ms apart in same fragment (< %d) - seam was not dropped",
+							gopFrames, fragIdx, tfdt, gap, maxBunchMs)
 					}
 				}
 				fragIdx++
 			}
 		}
 	}
+
+	if totalSync != wantSync {
+		t.Errorf("gop=%dframes: got %d keyframes in output, want %d - the truncated seam GOP was not dropped exactly once",
+			gopFrames, totalSync, wantSync)
+	}
+	if totalSamples != wantSamples {
+		t.Errorf("gop=%dframes: got %d video samples in output, want %d (= %d committed GOPs x %d frames) - the seam GOP drop removed the wrong frames",
+			gopFrames, totalSamples, wantSamples, committedGOPs, gopFrames)
+	}
+}
+
+// TestMP4LoopSeamDrop exercises the ~1s GOP case (30 frames @ ~33ms),
+// matching the original failing recording.
+func TestMP4LoopSeamDrop(t *testing.T) {
+	runLoopSeamScenario(t, 30)
+}
+
+// TestMP4LoopSeamDropLargeGOP exercises a larger ~2s GOP (60 frames). The
+// GOP size is configurable per camera; this guards against regressing to a
+// fixed-millisecond threshold that would only work for ~1s GOPs.
+func TestMP4LoopSeamDropLargeGOP(t *testing.T) {
+	runLoopSeamScenario(t, 60)
+}
+
+// TestMP4LoopSeamDropShortGOP exercises a short ~0.5s GOP (15 frames),
+// where a fixed ~1s threshold would misfire on every keyframe. The relative
+// detection must only drop the genuine premature seam's truncated tail GOP.
+func TestMP4LoopSeamDropShortGOP(t *testing.T) {
+	runLoopSeamScenario(t, 15)
 }

machinery/src/video/mp4_variablegop_test.go

@@ -0,0 +1,129 @@
+package video
+
+import (
+	"os"
+	"testing"
+
+	mp4ff "github.com/Eyevinn/mp4ff/mp4"
+	"github.com/kerberos-io/agent/machinery/src/models"
+)
+
+// TestMP4VariableGOPKeepsHealthyShortGOP reproduces the adam-drive regression:
+// a variable-GOP ("smart codec") camera lengthens its keyframe interval during a
+// static scene (e.g. 500ms -> 1500/2000ms) and then drops back to its normal
+// 500ms cadence on motion. That normal, FULL 500ms GOP arrives much sooner than
+// the immediately preceding (long, static) GOP.
+//
+// The previous heuristic compared the new keyframe interval against the *previous*
+// interval and dropped the GOP whenever gap < previousInterval/2 — so every normal
+// 500ms keyframe following a long static GOP was misclassified as a premature
+// loop/restart seam and a whole healthy GOP (~15 frames) was discarded. In the
+// field this silently deleted ~0.5s of video on virtually every recording from
+// such cameras, producing a freeze/jump artifact.
+//
+// After the fix the seam check compares against the running MINIMUM cadence and
+// additionally requires the buffered GOP to be genuinely truncated, so a full
+// healthy GOP is always kept regardless of how long the preceding GOP was. This
+// test asserts that NO frames are dropped for a pure variable-GOP stream.
+func TestMP4VariableGOPKeepsHealthyShortGOP(t *testing.T) {
+	tmpFile, err := os.CreateTemp("", "test_variable_gop_*.mp4")
+	if err != nil {
+		t.Fatalf("create temp: %v", err)
+	}
+	tmpFile.Close()
+	defer os.Remove(tmpFile.Name())
+
+	sps := []byte{0x67, 0x42, 0xc0, 0x1e, 0xd9, 0x00, 0xa0, 0x47, 0xfe, 0xc8}
+	pps := []byte{0x68, 0xce, 0x38, 0x80}
+	mp4Video := NewMP4(tmpFile.Name(), [][]byte{sps}, [][]byte{pps}, nil, 60)
+	mp4Video.SetWidth(1920)
+	mp4Video.SetHeight(1080)
+	v := mp4Video.AddVideoTrack("H264")
+
+	mk := func(k bool) []byte {
+		nt := byte(0x01)
+		if k {
+			nt = 0x65
+		}
+		f := []byte{0, 0, 0, 1, nt}
+		for i := 0; i < 200; i++ {
+			f = append(f, byte(i))
+		}
+		return f
+	}
+
+	const frameDur = uint64(33)
+	pts := uint64(0)
+	emitFrame := func(isKey bool) {
+		mp4Video.AddSampleToTrack(v, isKey, mk(isKey), pts, 0)
+		pts += frameDur
+	}
+	// emitGOP emits a complete GOP of exactly frames frames: a leading keyframe
+	// followed by frames-1 P-frames. Every GOP here is healthy and complete; only
+	// its length varies, exactly as a smart-codec camera varies the GOP.
+	emitGOP := func(frames int) {
+		emitFrame(true)
+		for i := 0; i < frames-1; i++ {
+			emitFrame(false)
+		}
+	}
+
+	// Normal cadence is 15 frames (~500ms). The camera then lengthens the GOP for
+	// several static scenes (45 and 60 frames, ~1500ms and ~2000ms) before
+	// dropping back to the normal 15-frame GOP on motion — the transition the old
+	// heuristic wrongly treated as a seam. The whole sequence is then repeated to
+	// cover multiple long->short transitions.
+	gopLengths := []int{15, 15, 45, 15, 60, 15, 15, 45, 15, 15, 60, 15}
+	totalEmittedFrames := 0
+	emittedKeyframes := 0
+	for _, n := range gopLengths {
+		emitGOP(n)
+		totalEmittedFrames += n
+		emittedKeyframes++
+	}
+
+	mp4Video.Close(&models.Config{Signing: &models.Signing{PrivateKey: ""}})
+
+	f, err := os.Open(tmpFile.Name())
+	if err != nil {
+		t.Fatalf("open: %v", err)
+	}
+	defer f.Close()
+	parsed, err := mp4ff.DecodeFile(f)
+	if err != nil {
+		t.Fatalf("decode: %v", err)
+	}
+
+	totalSamples := 0
+	totalSync := 0
+	for _, seg := range parsed.Segments {
+		for _, fr := range seg.Fragments {
+			for _, traf := range fr.Moof.Trafs {
+				if traf.Tfhd.TrackID != 1 {
+					continue
+				}
+				for _, trun := range traf.Truns {
+					for _, s := range trun.Samples {
+						totalSamples++
+						// sample_depends_on == 2 => "does not depend on others" => IDR/sync.
+						if (s.Flags>>24)&0x03 == 0x02 {
+							totalSync++
+						}
+					}
+				}
+			}
+		}
+	}
+
+	// Every GOP is healthy, so nothing must be dropped: all keyframes and all
+	// frames must survive. A shortfall means a normal variable-GOP keyframe was
+	// misclassified as a seam.
+	if totalSync != emittedKeyframes {
+		t.Errorf("got %d keyframes in output, want %d - a healthy variable-GOP keyframe was wrongly dropped as a seam",
+			totalSync, emittedKeyframes)
+	}
+	if totalSamples != totalEmittedFrames {
+		t.Errorf("got %d video samples in output, want %d - a healthy variable-GOP GOP was wrongly dropped as a seam",
+			totalSamples, totalEmittedFrames)
+	}
+}

machinery/src/webrtc/aac_transcoder_stub.go

@@ -96,7 +96,7 @@ func NewAACTranscoder() (*AACTranscoder, error) {
 				buffered := t.outBuf.Len()
 				t.outMu.Unlock()
 				if buffered <= 8192 || buffered%16000 == 0 {
-					log.Log.Info("webrtc.aac_transcoder: ffmpeg produced PCMU bytes, buffered=" + strconv.Itoa(buffered))
+					log.Log.Debug("webrtc.aac_transcoder: ffmpeg produced PCMU bytes, buffered=" + strconv.Itoa(buffered))
 				}
 			}
 			if readErr != nil {
@@ -129,14 +129,14 @@ func (t *AACTranscoder) Transcode(adtsData []byte) ([]byte, error) {
 		return nil, err
 	}
 	if len(adtsData) <= 512 || len(adtsData)%1024 == 0 {
-		log.Log.Info("webrtc.aac_transcoder: wrote AAC bytes to ffmpeg, input=" + strconv.Itoa(len(adtsData)))
+		log.Log.Debug("webrtc.aac_transcoder: wrote AAC bytes to ffmpeg, input=" + strconv.Itoa(len(adtsData)))
 	}
 
 	deadline := time.Now().Add(75 * time.Millisecond)
 	for {
 		data := t.readAvailable()
 		if len(data) > 0 {
-			log.Log.Info("webrtc.aac_transcoder: returning PCMU bytes=" + strconv.Itoa(len(data)))
+			log.Log.Debug("webrtc.aac_transcoder: returning PCMU bytes=" + strconv.Itoa(len(data)))
 			return data, nil
 		}
 
@@ -144,7 +144,7 @@ func (t *AACTranscoder) Transcode(adtsData []byte) ([]byte, error) {
 			if stderr := t.stderrString(); stderr != "" {
 				log.Log.Warning("webrtc.aac_transcoder: no output before deadline, ffmpeg stderr: " + stderr)
 			} else {
-				log.Log.Info("webrtc.aac_transcoder: no PCMU output before deadline")
+				log.Log.Debug("webrtc.aac_transcoder: no PCMU output before deadline")
 			}
 			return nil, nil
 		}

machinery/src/webrtc/main.go

@@ -26,7 +26,12 @@ import (
 
 const (
 	// Channel buffer sizes
-	candidateChannelBuffer = 100
+	// candidateChannelBuffer: large enough to absorb the burst of trickled ICE
+	// candidates that can arrive over MQTT before the SetRemoteDescription
+	// goroutine starts draining them. A small buffer caused candidates to be
+	// dropped silently on restrictive networks, leaving ICE stuck in
+	// "checking" until the viewer refreshed.
+	candidateChannelBuffer = 512
 	rtcpBufferSize         = 1500
 
 	// Timeouts and intervals
@@ -116,6 +121,22 @@ func (cm *ConnectionManager) RemovePeerConnection(sessionKey string) {
 	}
 }
 
+// CloseExistingPeerConnection closes and removes any peer connection currently
+// registered under sessionKey. Returns true if one was found. This is used to
+// reset state cleanly when a new request-hd-stream arrives for a session id
+// that the agent thinks is still active (for example after a viewer reload
+// where the previous PC hasn't yet been timed out by ICE).
+func (cm *ConnectionManager) CloseExistingPeerConnection(sessionKey string) bool {
+	cm.mu.RLock()
+	wrapper, exists := cm.peerConnections[sessionKey]
+	cm.mu.RUnlock()
+	if !exists || wrapper == nil {
+		return false
+	}
+	cleanupPeerConnection(sessionKey, wrapper)
+	return true
+}
+
 // QueueCandidate safely queues a candidate for a session without racing with channel closure.
 func (cm *ConnectionManager) QueueCandidate(sessionKey string, candidate string) bool {
 	cm.mu.Lock()
@@ -341,6 +362,17 @@ func InitializeWebRTCConnection(configuration *models.Configuration, communicati
 
 	// We create a channel which will hold the candidates for this session.
 	sessionKey := config.Key + "/" + handshakePayload.SessionID
+
+	// If a previous peer connection for this exact session is still hanging
+	// around (e.g. a viewer reloaded before pion's ICE timeout fired) close it
+	// first so we start from a clean slate. Without this, the new request would
+	// race against a stale PC that still owns the per-peer broadcaster tracks.
+	if globalConnectionManager.CloseExistingPeerConnection(sessionKey) {
+		log.Log.Info("webrtc.main.InitializeWebRTCConnection(): closed stale peer connection for session " + handshakePayload.SessionID)
+	}
+	// Drain/reset the candidate channel too \u2014 leftover candidates from the
+	// prior session are not valid for the new ICE agent.
+	globalConnectionManager.CloseCandidateChannel(sessionKey)
 	candidateChannel := globalConnectionManager.GetOrCreateCandidateChannel(sessionKey)
 
 	// Set variables
@@ -956,7 +988,7 @@ func processAudioPacket(pkt packets.Packet, state *streamState, audioBroadcaster
 		if len(pcmu) == 0 {
 			state.aacNoOutput++
 			if state.aacNoOutput <= 5 || state.aacNoOutput%100 == 0 {
-				log.Log.Info(fmt.Sprintf("webrtc.main.processAudioPacket(): AAC packet produced no PCMU output yet (aac_packets=%d, no_output=%d, input_bytes=%d)", state.aacPacketsSeen, state.aacNoOutput, len(pkt.Data)))
+				log.Log.Debug(fmt.Sprintf("webrtc.main.processAudioPacket(): AAC packet produced no PCMU output yet (aac_packets=%d, no_output=%d, input_bytes=%d)", state.aacPacketsSeen, state.aacNoOutput, len(pkt.Data)))
 			}
 			return // decoder still buffering
 		}
@@ -972,7 +1004,7 @@ func processAudioPacket(pkt packets.Packet, state *streamState, audioBroadcaster
 		state.lastAudioSample.Duration = sampleDuration(pkt, state.lastAudioSample.PacketTimestamp, 20*time.Millisecond)
 		state.audioSamplesSent++
 		if state.audioSamplesSent <= 5 || state.audioSamplesSent%100 == 0 {
-			log.Log.Info(fmt.Sprintf("webrtc.main.processAudioPacket(): queueing audio sample (samples=%d, codec=%s, bytes=%d, duration_ms=%d, peers=%d)", state.audioSamplesSent, pkt.Codec, len(state.lastAudioSample.Data), state.lastAudioSample.Duration.Milliseconds(), audioBroadcaster.PeerCount()))
+			log.Log.Debug(fmt.Sprintf("webrtc.main.processAudioPacket(): queueing audio sample (samples=%d, codec=%s, bytes=%d, duration_ms=%d, peers=%d)", state.audioSamplesSent, pkt.Codec, len(state.lastAudioSample.Data), state.lastAudioSample.Duration.Milliseconds(), audioBroadcaster.PeerCount()))
 		}
 		audioBroadcaster.WriteSample(*state.lastAudioSample)
 	}

machinery/swag.sh

@@ -1,2 +1,2 @@
 #!/bin/bash
-swag init -g ./src/routers/http/Server.go
+swag init -g ./src/routers/http/server.go