dtourolle
156b9e3684
Four bugs, one cause. "What can this device decode" was answered in five
places, four of which assumed the webview was decoding:
- the device profile's direct-play codecs (cfg per platform, inline)
- the transcoding targets (hardcoded "h264,hevc")
- the direct-play audio narrowing (webview list, all platforms)
- the client-side audio override (webview list, all platforms)
- get_video_stream_url's VideoCodec (hardcoded "h264")
On Android the decoder is ExoPlayer, so four of those were simply wrong there,
and the costs were invisible without a device:
- dts is in the tablet's own codec list, gets stripped from the profile, and
is then forced to transcode by a rule about a renderer that is not playing
it.
- An hevc source whose *audio* is eac3 had its **picture fully re-encoded**.
The server's own transcoding URL got this right — VideoCodec=h264,hevc,
TranscodeReasons=AudioCodecNotSupported, video copied — but the moment a
quality change or track switch re-opened the stream through our builder,
the hardcoded h264 turned a cheap audio remux into a full transcode. That
is a quality change silently making playback more expensive, on the exact
path a viewer uses when playback is already struggling.
`renderer_codecs()` and `renderer_can_decode_audio()` are now the single
source, and all five sites read them. On the webview path every value resolves
exactly as before, so desktop behaviour is unchanged by construction; on
Android the profile becomes the device's own.
The list is also what lets the server *copy* rather than re-encode: naming
every codec the renderer can decode is what turns a transcode into a
passthrough when the source is already playable. That is the whole of "use the
best format available".
Also corrects this branch's headline number where it is asserted — the
architecture doc, the desktop-native-video spec and the spike. The measured 85%
Android direct-play rate used a profile containing ac3/eac3; the device it was
later verified on reports neither, so eac3 content correctly transcodes there.
It is a ceiling for an ExoPlayer-appropriate profile, not what the app achieves,
and realising any of it depends on this change. Left in place with the caveat
rather than deleted, because the measurement is real — it just measures
something narrower than it was quoted as measuring.
Unverified: this changes what Android negotiates and has not been exercised on
the tablet yet. Desktop is unchanged by construction but also unre-tested.
JellyTau
A cross-platform Jellyfin client built with Tauri, SvelteKit, and TypeScript.
Business logic lives in a Rust backend; a UI-rich Svelte frontend handles presentation and talks to it over Tauri's IPC. Targets Linux (libmpv) and Android (ExoPlayer).
Getting Started
This project uses bun as its package manager.
# Activate the Rust environment (fish shell)
source "$HOME/.cargo/env.fish"
# Install dependencies
bun install
# Run in development
bun run tauri dev
# Type-check the frontend
bun run check
# Build for Linux
bun run tauri build
# Build for Android
bun run tauri android build
For the full set of build, test, and Android helper scripts, see scripts/README.md.
Documentation
| Topic | Location |
|---|---|
| Architecture overview & subsystem docs | docs/architecture/ |
| Requirements, traceability & technical debt | docs/requirements.md |
| Build & release process | docs/build/build-release.md |
| Docker builds | docs/build/docker.md |
| Traceability tooling & CI | docs/traceability.md, docs/traceability-ci.md |
| Release checklist | docs/release-checklist.md |
| UX flows | docs/ux-flows.md |
| CI operations (builder image, secrets, runner) | docs/build/ci-operations.md |
Contributing
CONTRIBUTING.md covers the setup, the gates a change has to pass, and the two rules that catch people out (bug fixes start with a failing test; Jellyfin's taxonomy stays in Rust). Please also read the Code of Conduct.
Found a security problem? Do not open an issue — see SECURITY.md.
Verifying a download
Every release publishes SHA256SUMS covering all of its artifacts, plus an SBOM
of what went into the build:
sha256sum -c SHA256SUMS
Desktop builds update themselves from Settings → Updates, verifying each payload against JellyTau's signing key before installing. Android installs are handled by the system installer, so the app links to the releases page instead.
Recommended IDE Setup
VS Code + Svelte + Tauri + rust-analyzer.
License
MIT