First real recording (2026-09-01): ffmpeg died at ~0.9s mid-session with ZERO log
lines while the pump fed a corpse for 9 more seconds. Three blind spots closed:
- OnStderrLine discarded everything non-progress: ffmpeg's actual words (startup
config, warnings, the reason it quit) now go to AppLog prefixed 'ffmpeg:' (400-char
cap so a \r-choked blob can't flood).
- Unexpected exit only fired ProcessFailed when code != 0 — a CLEAN exit vanished
silently. Any exit we didn't request is now logged and fired, any code.
- ExitCode read raced StopAsync's Dispose (tonight's 'No process is associated'
line) — guarded.
- VM output resolver logs once/5s when a webcam element resolves to a null frame
(preview showed the cam, recording didn't — the layer skip was invisible).
FfmpegEncoderTests + FramePumpTests 21/21 against the new code, 0 warnings.
The 2026-08-09 pin was a DAILY build; BtbN retention aged it out and the cold-cache
download 404'd on the creator's first native recording attempt (2026-09-01,
startup.log). Re-pinned to the MONTH-END build autobuild-2026-08-31-13-27
(N-126342, lgpl-shared win64 — 2-year retention; tag+variant recorded in TASKS.md
per the licensing rule). Verified alive: HEAD 200 + zip contents (bin/ffmpeg.exe,
bin/ffprobe.exe, 7 libav DLLs) match the name-agnostic extractor.
Also closes the wrap-gap: HttpRequestException escaped the locator untouched,
surfacing a raw 'Response status code... 404' from the frame pump; now wrapped in
IOException with the refresh-pin-or-install-ffmpeg message. FfmpegLocatorTests 7/7
(one updated, one added for the 404 case).
- FfmpegFrameRateParser (pure): prefers avg_frame_rate= then r_frame_rate=,
rational N/N/M, unknown/0 -> null.
- IFrameRateProbe + FfmpegFrameRateProbe: derives sibling ffprobe.exe from the
located ffmpeg dir, reuses the IDecodeProcess seam for the ffprobe subprocess
text; null if ffprobe absent.
- FfmpegLocator now also extracts ffprobe.exe (ProbeFileName) from the pinned
archive, conditional so old caches without it degrade to no pacing.
- Tests: 6 pure parser units + 1 probe integration via fake locator/process;
FfmpegLocatorTests still green. 15/15, 0 warnings.
Pacing (probe->delay) is slice 2b. Derivative reference: standard ffprobe
avg_frame_rate probing used across OBS/media tooling.
- Add ElementKind (Static/Dynamic) to SceneElement base; Source/WebcamSceneConfig classify
- Services/SceneGraph.cs: owns the Scenes collection (ViewModel's Scenes delegates to it),
the element mutation surface (Add/Insert/Remove/Move, each invalidating the bake), and the
queries that were scattered LINQ (GetBackground/GetWebcam/GetChatBoxes/GetSplitPoint/IsStatic)
- SceneCompositor: split-aware BakeStaticBase + CompositeLayers + Render(.., staticBase, split);
builds/caches the static base below the split point in source-rect space
- FramePump: optional SceneGraph -> optimized bake+composite path; falls back to full render
- MainViewModel: routes element mutations through the graph; invalidates the bake on static
layout/opacity/visibility/useDefaultBackground changes and after background heal/Ensure
- Integration test SceneGraphTests.BakedStaticBase_WithDynamicLayer_CompositesCorrectly
Derivative survey (mandated): tried before writing — OBS does per-source opacity/visibility
caching and static-scene baking; this mirrors OBS's 'cached static source' optimization.
3 documented defensive deviations from the spec (ChatOverlayLayer stays decoupled;
background helpers stay VM-static for direct testability; full facade peel deferred post-1.0)
in TASKS.md + ai.md. Scope check passed; clean build 0 warnings.
Encoder dual-output: StreamEnabled/RecordEnabled/RecordPath options; per-output
ffmpeg block (stream ->flv, record ->mp4); throw unless at least one output.
RecordingFile: auto-name ty-<yyyymmdd>-<start hhmm>-0000.mp4, rename-on-stop to
ty-...-<len hhmmss>.mp4 with numeric-suffix on collision. LayoutStore persists
record folder. MainViewModel: REC/ON-AIR pills, status light, single Start<->End
button (replaces Start/Stop variants), StopStream no longer signs out, explicit
session timer. About overlay widened. Sign In label + spacing before Start.
Tests: 244 passed / 246 (2 pre-existing: AudioPipeline gains-mute, RoundClip).
Build 0 warnings. Scope check clean.
Memory-map correction (derived-solution rule, 2026-08-29): image-shrink recipe was
never recorded when first done, so it was re-derived. Added Derived-solution/recipes
rule to AGENTS.md; MyMistakes.md now a permanent recipes registry (records the
verified WPF-imaging shrink recipe); schema.md rows MyMistakes as registry; ai.md
points to the rule. README hero image replaced: 3.2MB screenshot -> 1400x794 ->
188KB docs/ytLlive-preview.jpg (JPEG q82).
IFfmpegLocator seam that resolves ffmpeg.exe (PATH -> cache -> pinned download),
plus the licensing compliance that makes a paid GA product defensible.
NOTE FOR USERS: this change shows NO difference in the app's behavior except a
new top-bar "About" button (opens THIRD-PARTY-NOTICES.txt). It is scaffolding
for the encoder/streaming work.
- Services/Encoder/: IFfmpegLocator + FfmpegLocator. Pin is BtbN lgpl-shared
autobuild-2026-08-09-13-03 (NOT gyan.dev/GPL or static: LGPLv2.1 §6 static
relink material avoided by dynamic linking); extracts ffmpeg.exe + libav*.dll
via a staging dir so a crash never leaves a partial cache
- THIRD-PARTY-NOTICES.txt: LGPL/BSD/MIT notices + source offer, copied to the
build output, surfaced by the About button; v1 gate = bundle full license
texts (TASK 4 requirement 9)
- ai.md "Licensing - do not violate" guardrails (never GPL/nonfree/static/latest-
tag, never link FFmpeg in, never drop notices); TASKS.md + Services/index.md
updated
- Tests: FfmpegLocatorTests - hermetic decision-ladder integration test + shared-
build DLL extraction + edge cases; docs updated (78 tests passing, 0 warnings)
gramps