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).
Add independent AppLog message types and explicit Class 1/2 severity. Wrap and color log rows, pin Class 1 above Class 2, and let acknowledgement return entries to the current-launch timeline without changing file format or rotation.
Ref: https://logtape.org/manual/levels
Routing and ruling both good: 'procs in the chat windows but nothing in the alert box'
with zero exceptions — every failure stage was silent by design (Debug.WriteLine-only
preview catch, bare catch{} in RunAsync firing Completed regardless). A decode run that
starts but yields neither a frame nor an audio chunk left _clip != null with
_latestClipFrame == null, so RenderClipFrame returned null forever: the box stayed
transparent for the whole alert and the six-animation fallback (which only ran on
setup-time throws) never fired.
Fix: AlertOverlayLayer.Advance gives a started clip a NoFrameFallbackSeconds (1.0s)
grace — produce no frame AND no audio inside it and the clip is torn down, _elapsed
resets, and the SAME alert continues as the animation branch (never blank, never drained
early). Diagnostics stop the lying silence: BeginClip logs box id/path/size + setup
failures; AlertClipDecoder.RunAsync logs frame/chunk end-state and the exception it used
to swallow.
Good Dog test: SilentDecoder_FallsBackToTheAnimationAfterTheNoFrameGrace (transparent
inside grace, disposed past it, animation renders, drains to idle).
Reference: alert playback must degrade to its fallback on dead-air, never vanish —
same contract as every player/booth failure budget (e.g. OBS source fallbacks).
https://obsproject.com/forum/threads/source-visibility-fallback.187383/
TASK 43's alert box grows a real video celebration. Per-alert IAlertClipDecoder
(ffmpeg bgra + f32le pipes, real-time paced, disposed at drain) plays the shipped
Assets/alert-default.mp4 (stamped into the Asset table at startup) unless the
creator picks their own file — path reference only, never stored in the DB; the
six AlertRenderer animations stay the fallback. ~0.3s fade rides the alpha
envelope on straight-source copies (EOF freeze-frames then fades out); audio
forwards to a new AudioMixer alert ring (8s, 48k stereo) drained at unity — no
duck, creator ruling — scaled by volume × fade. An auto-composed marquee ticker
('Funder — Super Chat · $10.00', 140px/s) scrolls top-of-frame via a
FramePump._alertTicker seam through Render/CompositeLayers, mixed into the cache
signature (dynamic overlay, never baked). New Stream Alerts section in LeftPanel.
Derivative-work references (how OBS/Streamlabs alert boxes do per-alert video):
- https://support.streamlabs.com/hc/en-us/articles/217741147-Setting-Up-Your-Streamlabs-Alerts (custom image/video per alert type + variations)
- https://obsproject.com/kb/stream-tutorial-2-alerts (alert overlay as an on-screen zone)
- https://streamlabs.com/content-hub/widgets/alert-box (per-event alert playback)
Good Dog: AlertLayerVideoTests drives a fake IAlertClipDecoder through the whole
lifecycle in one pass (custom path wins, decoder spawns/disposes, fade envelope
0→127→255, audio volume×fade, ticker scrolls, EOF fade-drain to idle). It caught
the clip branch of Advance not clearing _current before AdvanceToNext — the layer
stayed IsPlaying after drain (MyMistakes post-mortem).
Full vstest 319/319; clean build 0 warnings; scope check green.
gramps