TASK 64 slices D and E: the feature is usable end to end.
- Add a video file → one frame is probed (new `IChromaProbe`/`FfmpegChromaProbe`, one ffmpeg
pass at 160x90, off the UI thread) and the layer gets an offer: "Looks like a green screen —
Remove it", with the measured colour as a swatch.
- Accepting it turns the offer into settings (Amount / Softness / Fringe) that reach ffmpeg as
`colorkey` + `despill` + `format=bgra`, so the key is computed in the pipe and both consumers
(the shared preview bitmap and the compositor's frame) carry the same alpha.
- Media sessions are now keyed by **path + look** (`MainViewModel.MediaSessionKey`), so two
layers with the same settings still share one decoder, and changing the look releases the old
session and starts the new one. Removal, load reconciliation, loop and audio settings all move
to the same key.
- Settings persist on the `Source` row (six ALTER TABLE guards + SELECT/INSERT), so a keyed layer
comes back keyed.
- Panel section is plain creator words: Green/Blue Screen, Amount, Softness, Fringe.
Test: `ChromaKeyApplyTests` — the pipe asks ffmpeg to key (and does not when off); a green-screen
clip is offered, accepting it starts a keyed session, the layer's resolver then reads that session
rather than the old one; the setting survives a save.
Docs: TASK 64 D/E ticked with slice F (auto-apply setting + alert clips) left open; frame-pipeline
records the decode-option design; HANDOFF rewritten. verify.sh: 544 passed, 0 failed, 0 warnings.
A video file was picture-only: the decode pipe passed `-an`, so a starting-soon
or BRB clip with music played silent everywhere. Adds sound to every clip and
collapses the two decoders into one.
- `Services/VideoClipPipe.cs`: the shared pipe behind `MediaVideoSource` (TASK 21)
and `AlertClipDecoder` (TASK 47) — video (`rawvideo bgra`, scaled) + audio
(`f32le -ac 2 -ar 48000`, 50 ms chunks, byte-carry across reads), both paced to
real time, loop restarts both so picture and sound stay together. Alert
behaviour is unchanged.
- `MediaVideoSourceManager` applies the layer's Level/Mute per session and raises
`AudioAvailable`; `MainViewModel` feeds it to the new
`AudioMixer.EnqueueDesktopMediaAudio`, which joins the DESKTOP/GAME ring so the
desktop fader and the mic auto-ducker apply exactly as they do for game audio
and TRAX (creator ruling 2026-11-05: audio joins the group).
- Per-layer `MediaMuted` + existing `MediaVolume` surfaced as Mute/Level in the
properties panel; `MediaMuted` persisted (ALTER TABLE guard + SELECT/INSERT).
- Level/mute are per SESSION because one decoder is shared per file path — the
last layer touched wins; one decoder per layer would play the file twice.
Test: `MediaSourceAudioTests` — the pipe emits 50 ms chunks at 48k stereo, the
manager scales by level and drops when muted, and a media layer's sound moves the
desktop meter. Alert/decode suites unchanged and green.
Docs: task-21 closed on item 10, the "silent soundtrack" facts corrected in
frame-pipeline/output/overlays, HANDOFF rewritten. verify.sh green (529 passed;
the two documented pre-existing failures only).
- IMediaFrameSource gains bool Looping.
- MediaVideoSource ctor takes Func<IDecodeProcess> processFactory instead of a
single IDecodeProcess: a System.Diagnostics.Process can't be re-Start()ed, so
each loop pass creates a fresh decoder. Decode wrapped in do-while(Looping):
restart on natural EOF instead of raising Completed.
- Production wiring (MainViewModel media factory): passes the process factory
AND FfmpegFrameRateProbe -- closes the slice-2b gap where production had no
probe and therefore no pacing.
- Tests: loop test (single frame re-emits across passes, Completed only when
loop cleared); fakes updated for the new interface member. Media tests 12/12,
build 0 warnings.
Wiring Source.MediaIsLooping into the flag needs a manager-level per-path loop
provider -> lands with the UI-picker (acquisition) slice.
Derivative reference: looping media by restarting decode on EOF, standard in
playback/overlay tooling (OBS media source repeat).
- MediaVideoSource takes optional IFrameRateProbe? + Func<TimeSpan,CancellationToken,Task>? delay
seams (default Task.Delay); probes FPS once in RunAsync, delays by 1/fps after each
emitted frame. No probe/unknown fps -> no pacing (ffmpeg pipe backpressure throttles).
- Test: MediaVideoSource_PacesFramesByProbedFps (fake probe returns 1000fps + recording
delay; one delay per frame ~= 1ms). Media tests 5/5, build 0 warnings.
Derivative reference: per-frame delay pacing of decoded output, standard in media playback.
Adds the codec-agnostic decoder half of the media source. Spawns ffmpeg
with -f rawvideo -pix_fmt bgra (reusing the already-shipped ffmpeg via
IFfmpegLocator) and drains the raw BGRA stdout pipe into VideoFrames.
- Services/RawVideoFrameReader.cs: pure rawvideo BGRA stream -> frames
(partial reads kept across Feed; no ffmpeg needed to test)
- Services/IDecodeProcess.cs + FfmpegDecodeProcess.cs: binary-stdout
subprocess seam, mirror of the encoder's IEncoderProcess
- Services/MediaVideoSource.cs: owns the decode, raises FrameReady/Completed
- MediaVideoSourceTests: 3 pure reader + 1 integration (fake decode
process through the real source loop, frames in order)
Reference (external scan): ffmpeg rawvideo pipe decode is the canonical
codec-agnostic frame feeds pattern (ffmpeg docs -f rawvideo; how OBS/media
pipelines push frames to a compositor). Verified: 4/4 tests, build 0 warnings.
Native-FPS pacing + resolver/compositor wiring are the next slice.
gramps