Frigate Android

A native Android port of the Frigate NVR — live RTSP camera viewing, motion‑triggered recording, and configuration, built to mirror the look and behavior of the desktop/Linux Frigate web UI.

Package: com.zektopic.frigate · Kotlin + Jetpack Compose · min SDK 26 (Android 8.0) · target/compile SDK 34.

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Features

Live

• Multi‑camera wall — adaptive grid (LazyVerticalGrid) with 16:9 tiles; a NavigationRail on tablets/landscape and a bottom bar on phones.
• Real RTSP playback via Media3/ExoPlayer, including H.265/HEVC streams.
• Honest per‑camera connection state — LIVE / CONNECTING / RETRYING / OFFLINE, with exponential‑backoff reconnect. No fake or simulated feeds, ever.
• Tap a tile for a fullscreen single‑camera view.
• Per‑camera Detect / Record / Snapshots toggles that actually gate behavior (see below).

Review

• Motion events with snapshot thumbnails, relative timestamps, and camera filter chips.
• In‑app playback of the recorded MP4 clip once it finalizes.

System

• Real device metrics (app CPU, memory, storage) and a per‑camera status/FPS/resolution table.

Settings

• Camera manager + 3‑step wizard (add/edit/delete) with a live RTSP connection test (DESCRIBE probe reporting reachability + codec).
• Global configuration — MQTT host/port, detection defaults, tracked objects.
• Notifications — master switch, alert‑on‑motion, and per‑camera mute (backed by DataStore, enforced by the service).
• Storage — recordings count / on‑disk size and a "clear all recordings" action.
• About — app/config version, camera & event counts, device info, storage path.
• Advanced — a raw YAML editor for the full Frigate‑style config.

Recording

• Motion‑triggered MP4 clips encoded on‑device (MediaCodec AVC via an EGL/GLES input surface), attached to their event for playback.

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How it works

• NvrService — a foreground service that owns the camera streams. It observes the config from Room, starts a StreamIngester per enabled camera, runs motion detection, records clips, and posts notifications (gated by the user's preferences).
• StreamIngester — drives an ExoPlayer RTSP session, extracts frames via an offscreen EGL pipeline, and manages the connection state machine + reconnect. For H.265 streams whose SDP omits the parameter sets, it sniffs the VPS/SPS/PPS in‑band and self‑heals on reconnect (see H.265 notes).
• Config is YAML‑first. The Frigate‑style YAML in Room is the single source of truth; the UI (wizard, global form, live toggles) edits that YAML and the service hot‑reloads from it. The per‑camera Detect/Record/Snapshots switches map to cameras.<id>.{detect,record,snapshots}.enabled and are consumed by the service to gate event logging, recording, and snapshots independently — toggling one does not restart the stream.
• Embedded web server — a Ktor server runs inside the service for local API access.

Cameras go through go2rtc

Point the app at your go2rtc restreamer, not directly at cameras. Direct camera URLs exhaust the cameras' 1–2 RTSP session slots (already held by Frigate/birdseye), so DESCRIBE succeeds but no RTP ever flows. Example seeded URL: rtsp://<go2rtc-host>:8554/<stream_name>.

H.265 notes & known limitation

H.265 cameras that omit sprop-vps/sps/pps from their SDP are handled by in‑band parameter‑set sniffing. Very high‑resolution HEVC streams from some vendors may still fail to decode on a given Android device even when they play on a desktop (which uses ffmpeg/browser decoding). The robust fix, mirroring real Frigate, is to expose a lower‑resolution or H.264 substream in go2rtc and point that camera's URL at it.

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Tech stack

Jetpack Compose · Hilt (DI) · Room · Media3/ExoPlayer 1.3.1 (RTSP) · Ktor (embedded server) · SnakeYAML · DataStore · MediaCodec/EGL (recording).

Toolchain: AGP 8.5.1 · Gradle 8.7 · Kotlin 1.9.22 · JDK 17.

Build & run

./gradlew assembleDebug          # build the debug APK
./gradlew testDebugUnitTest      # run unit tests
./gradlew installDebug           # install on a connected device

CI (.github/workflows/android-build.yml) runs lint, unit tests, and packages the debug APK on every push.

First run

The app seeds a default config on first launch only (gated on the real DB, so your edits are never overwritten on restart). Open Settings → Cameras to add your own cameras with the wizard, or edit the YAML under Advanced.

Project layout

app/src/main/java/com/zektopic/frigate/
├── MainActivity.kt              # Compose host, service binding, first-run seeding
├── service/NvrService.kt        # foreground service: streams, detection, recording, alerts
├── media/
│   ├── StreamIngester.kt        # RTSP ingest, frame extraction, H.265 sprop sniffing, state machine
│   ├── ClipRecorder.kt          # motion-triggered recording sessions
│   └── VideoClipEncoder.kt      # MediaCodec AVC + EGL MP4 encoder
├── ui/
│   ├── dashboard/DashboardScreen.kt   # Live / Review / System / Settings
│   └── settings/                # camera wizard, YAML editing, settings sections
└── data/                        # Room entities, DAO, YAML parser, preferences