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.
Specs index
Feature specs for JellyTau. Start a new one from SPEC-TEMPLATE.md and run it past SPEC-REVIEW-CHECKLIST.md before accepting it.
What lives here
Only work that has not shipped. Once a spec is fully implemented its design is folded into the architecture docs — which are the maintained description of the build — and the spec file is deleted. Git history keeps the original, including its rejected alternatives and acceptance criteria; the architecture docs keep the reasoning that a future change still needs.
So: a file in this directory is a promise, not a description. If you want to know how something works, read docs/architecture/. If you want to know what is planned, read here.
Status vocabulary
| Status | Meaning |
|---|---|
| Proposed | Written, not accepted. Nothing built. |
| Accepted | Agreed as the design; implementation not started or not finished. |
| Partially implemented | Some parts shipped; the spec names what is left. |
| Design authority | No code of its own — it records a decision later specs act on. |
Next free requirement ids (always re-check requirements.md before allocating): UR-079, IR-033, DR-231. Three specs below suggested ids that have since been taken by other work; each carries a ⚠️ note at the top.
Partially implemented
| Spec | What landed | What is left |
|---|---|---|
| frontend-domain-model.md | Catalog surface: MediaKind, from_jellyfin isolated, ticks → ms |
primaryImageTag → imageId (~30 sites); player/session/reporting tick math; stream.type |
| libmpv2-migration.md | LICENSE |
The libmpv → libmpv2 crate swap |
| read-through-media-cache.md | DR-126…128, DR-133…138 — cache entries are download rows; local playback of downloads | DR-122/124/125 — the read-through capture. DR-121 shipped as backend-owned stream selection and left this spec |
| scoped-search-boundary-implementation.md | Stage 1: SearchScope owned by Rust (DR-063…067) |
Stage 2: result-side grouping (GROUP_ITEM_TYPES still in searchScope.ts) |
Not started
| Spec | Blocked on / note |
|---|---|
| desktop-native-video.md | mpv draws video on every desktop platform, then the webview <video> path and hls.js are deleted. Converts a measured 7% direct-play rate toward Android's 85%. Stacked on backend-owned stream selection. |
| build-provenance.md | build.rs is still bare. ⚠️ suggested id DR-093 is taken. |
| player-facade-enforcement.md | ~60 commands.player* sites still outside the facade; no lint rule. ⚠️ suggested id DR-095 is taken. |
| windows-native-audio-backend.md | Blocked on the libmpv2 swap. ⚠️ suggested id IR-030 is taken. |
| linux-native-video-spike.md | Spike run 2026-08-21: compositing works on Linux, X11 and Wayland. G1-G6 green bar the Tauri default_vbox() half of G1. The adaptive-bitrate question it was waiting on is answered: the server publishes one EXT-X-STREAM-INF, so there is no ladder for mpv to lose (DR-228). StreamSelection (DR-224) is the contract to consume. |
Design authority
| Spec | Role |
|---|---|
| playback-backend-unification.md | Why video cannot unify onto one native engine and audio can. The audio half has since shipped on Android; Windows has not. |
| scoped-search-boundary.md | The boundary design the check:boundary rule came from. Stage 1 built. |
| scoped-search.md | Superseded in part — its "frontend only, no Rust changes" decision is the leak the boundary spec reversed. UX still current. |
Where the shipped specs went
Sixteen specs were folded into the architecture docs and deleted (2026-08-21). Where to look for each:
| Shipped work | Now documented in |
|---|---|
| Account menu & global chrome | 02-svelte-frontend.md — App Shell and Chrome |
| Library mosaic | 02-svelte-frontend.md — Library Mosaic |
| Series current-episode navigation | 02-svelte-frontend.md — Series and Episode Navigation |
| Downloads as an offline library | 02-svelte-frontend.md — Downloaded Browse |
| Favourites browsing | 01-rust-backend.md — Favorites System |
| Streaming bitrate cap | 01-rust-backend.md — Streaming quality ladder |
| Locally-indexed search | 03-data-flow.md — Search Flow; 01-rust-backend.md — Background workers |
| Offline downloaded-only filter | 06-downloads-and-offline.md — Offline Catalog Visibility |
| Audio equalizer · Android audio settings parity | 05-platform-backends.md — Audio settings on ExoPlayer |
| Android native video spike | 05-platform-backends.md — Native Video Compositing |
| Video background audio | 05-platform-backends.md — Background Audio Handoff |
| Traceability gate repair | traceability-ci.md |
| Boundary tripwire hardening | scripts/check-frontend-boundary.sh (its header is the spec) |
| Playback docs corrections · req-coverage script removal | Nothing to document — both were corrections that have been applied |