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.
- 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.
ai.md: Key patterns gains the 'true decomposition beats partial-shuffling'
rule + the glue-vs-component diagnostic (count OnPropertyChanged/SetProperty;
extract only zero/low-glue cohesive state blobs like chat's; leave binding glue
over already-extracted services alone; line count is a guideline not a goal).
ViewModels table row notes Chat.cs is now a thin facade over ChatOverlayLayer.
HANDOFF: everything through Commit G is pushed (origin/main=85893ea); the
remaining big decomposition is the scene-graph segment, flagged as design-needed
(not an unsupervised peel).
Rewrite HANDOFF.md: Phase 2 is pushed at 1f4624c (stale claim corrected);
Phase 3 commit rows A-E + Controls/index.md listed as local-only, push pending
on explicit approval. Records the re-structuring principle (split by concern,
500-line count is a ceiling not the goal) and the session's truncation-accident
lesson. MyMistakes.md gains the never-awk-into-the-source-you-read rule.
Working tree clean. Phase 1 (pushed) + Phase 2 (local-only, commits 12-18 with
tags) both complete. Push checkpoint reached: next step is 'git push origin main
&& git push --tags' on explicit user approval. Landmines updated with the XAML
extraction gotchas (control xmlns, name-looked-up host stubs, window-resources
converter rule).
Zero behavior change: \`public class\` -> \`public partial class\`. Each functional area
(Scenes, Background, Webcam, Audio, Trax, Socials, Streaming, Chat, Overlays,
Account, License) will move to its own file next, one commit per partial — each
a roll-back point. Docs updated in the same commit: ViewModels/index.md (split
map), ai.md (architecture table), HANDOFF.md (state). verify.sh: build 0 warnings,
only the 2 known pre-existing test failures.
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).
Project lesson cited (the 2026-08 web-box saga, 9 commits): browser sources are fixed canvases
per OBS convention — the 'gap' was a widget CSS glow, not a bug.
Root-cause note: the apparent remaining gap was a WIDGET GLOW EFFECT (the widget's own CSS glow pushed
out its perceived borders), not a code bug — the alpha-bbox already hugged the glow halo. Verified
perfect with a second widget without the effect.
- FindContentBounds already trimmed the bitmap; the grid/box still rendered at the uncropped user
size, so Fill stretched the tight widget into a bigger frame = dead-between-content-and-border.
- ContentCanvasSize maps the crop rect to canvas units (1920/pixW per axis, DPI-correct) and the
preview event now carries (bitmap, canvasW, canvasH).
- OnWebView2PreviewBitmapChanged sets the element Width/Height to that size; the grid and the
SelectionOverlay (both bound to the element's Width/Height) now equal the widget exactly.
- IsPreviewDragging (set in MainWindow drag/resize) suppresses auto-fit mid-gesture.
- Tests 10/10 (alpha bounds, canvas-size mapping incl. DPI, control size); 0 warnings.
- FindContentBounds scans the Bgra32 capture for the bounding box of non-transparent pixels
(background is injected transparent, so alpha = widget extent). Crop to that rect + Stretch=Fill
maps the widget flush under the selection box: full-canvas widgets fall through to the full frame
(identical to the confirmed-good image); floating widgets get tight-fitted with no dead space.
- Removes QueryContentBoundsAsync + the JS script entirely — the DOM-union attempt (a5b9952) broke
rendering by measuring an unsettled layout on NavigationCompleted; alpha measurement is immune.
- 3 new unit tests: tight box, no-alpha no-crop, full-alpha no-crop. 7/7 pass, 0 warnings.
- QueryContentBoundsAsync now returns a real JS object (not JSON.stringify — ExecuteScriptAsync
double-encodes strings, which silently killed the old crop) and measures the union of every
visible body element's getBoundingClientRect: the widget's actual rect, top-left offset included.
- CaptureFrame crops AT that offset (x,y) instead of from (0,0), so the widget anchors at origin
and the box is flush on right/bottom. Fill maps the frame flush under the box.
Bundle exception (2026-08-27): this lands prior-session work plus today's
transparency fix as one commit per creator instruction.
WebView2Manager (new): off-screen WebView2 control parked at -5000/-5000 in
the window's visual tree, captures via CapturePreviewAsync every 100 ms into
a BGRA8 VideoFrame. Source Width/Height sync to the control via
PropertyChanged. JS transparent-background injection runs on every
NavigationStarting/NavigationCompleted so the page's own CSS does not paint
white over the capture.
Transparency fix: DefaultBackgroundColor = System.Drawing.Color.Transparent
set on the WPF control before EnsureCoreWebView2Async. The WPF SDK doc says
the value is forwarded to the controller on init; the IDL (ICoreWebView2-
Controller2) confirms alpha=0 makes the capture alpha-preserving. The
prior-session 'CoreWebView2.BackgroundColor' path was the wrong property
name and has been replaced.
LayoutStore: WebUri column added (idempotent ALTER TABLE) and round-tripped
on save/load (schema v11).
MainViewModel: WebView2Manager constructed on Loaded; loaded web sources
re-registered; Source.WebUri PropertyChanged forwards to manager.
MainWindow: off-screen host Canvas added to visual tree.
Tests: 3 scale-sync + WebView2_DefaultBackgroundColor_Is_Transparent +
LayoutStorePersistenceTests.WebSource_WebUri_Persists. 234/236 pass
(2 pre-existing failures unchanged).
Scale bug (DPI/physical-pixel mismatch) still open.
gramps