Creator reported the layer reorder still "doesn't save" after the 08:18
fix (c117885). The existing Good Dog test short-circuited EndListDrag — it
called OnSceneElementsReordered() directly, so the actual
List_PreviewMouseLeftButtonDown/Move/Up handlers were never exercised
(synthetic RaiseEvent can't: e.GetPosition reads the physical cursor).
New RealMouseDrag_OnTheLayerList_PersistsTheReorder drives SetCursorPos +
mouse_event (Win32 input injection, the same technique UI-automation
tooling uses) so the REAL handlers run: click ImgC's row, drag it onto
ImgA's row on screen, release, then pump until the debounced save writes
the DB. Green: DB ends at [Background, ImgC, ImgA, ImgB] — the seam is
proven end-to-end. If the creator still sees a revert, the run binary was
stale (Debug exe 08:42 postdates the fix commit 08:18) or another deploy.
Reference: Win32 SendInput/mouse_event input injection for WPF e2e
(mouse_event docs / UI-automation tooling pattern).
RenameRecordingDialog was 230px tall for ~225px of stacked content —
the file-name textbox clipped (old client area ~193px). Height is now 276
(+20%). Integration test shows the real dialog in the app host and asserts
the textbox bottom edge stays inside the client area; the dialog's Icon moved
to the explicit /ytLive;component/ URLC form MainWindow already uses so tests
can construct it (root-relative /Assets/... only resolves in production via
Application.ResourceAssembly).
Dependency fix: MainViewModel.Shutdown() now calls
_fullScreenDetector.StopWatching(). The global EVENT_SYSTEM_FOREGROUND hook
was never unhooked; after VM collection the next foreground event invoked a
garbage-collected WinEventProc delegate, crashing the whole test run. Harmless
in production (exits the process) but fatal in the multi-window test host.
Reference: WPF WinEvent hook lifecycle guidance — SetWinEventHook callbacks
must be unhooked before the owning object is collected (obs-projector
fullscreen-detection pattern).
List_PreviewMouseMove reorders StagedScene.Elements via RemoveAt/Insert,
bypassing SceneGraph's mutation surface, but never scheduled a save — the
new z-order was lost on restart. The drop now sets _dragReordered and
EndListDrag funnels it through MainViewModel.OnSceneElementsReordered()
(InvalidateBake + ScheduleSave, same background-save path as every other
mutation). Integration test (RealApp + temp DB) reproduces the exact
code-behind mutation and asserts the debounced save lands the new Source
SortOrder. Derivation reference: standard WPF ItemsControl drag-reorder
pattern (OBS layering semantics: bottom-most layer = index 0).
Creator refinement: 'offered iff there's not one already configured & attainable'.
CanAddWebcam now requires IsWebcamAttainable = identity present AND a RUNNING
session (CameraManager.IsRunning) — an identity whose camera was unplugged or
whose lock keeps failing leaves the row greyed with reason 'No webcam is
currently available…', and it un-greys the moment a session is live. Gate
re-raised at every attainability flip: staging, removal, startup lock success,
first frame, camera failure, identity swap.
Root cause the old test surfaced: the startup pass skipped acquiring when the
loaded identity's configs already held the session, so there was no independent
app base ref — removing the last placement dropped RefCount to 0 and killed the
session. The single-camera branch now ALWAYS acquires (a running session just
bumps), laying the app-wide base hold so the default outlives the scenes.
Good Dog: WebcamMenuGateTests second fact — identity loaded, session can't start
→ row NOT offered + 'No webcam is currently available…' tooltip. Positive fact
waits for WebcamStartupValidationTask to make the IsRunning read deterministic.
Docs same commit (ai.md gate + base-lock, TASKS.md, HANDOFF.md incl. proven
pre-existing audio flake). 305 tests (304 pass + known flake), 0 warnings.
Chat's camera no longer greys Web Cam in Live (per-scene max, not app-wide);
TASK 26 superseded by creator directive (app-level resource model). Add Webcam
now places the existing app default without the picker; the picker runs only
for the initial selection. Removing the last placement keeps the identity
(_webcam never nulled) so Add stays offered. Startup pass adopts a solo camera
as the app default, so a clean layout offers the layer in Live/Chat at once.
Dynamic WebcamAddToolTip names the why (incl. the 'graduated to OBS' line).
Good Dog: WebcamMenuGateTests rewritten (real app + temp DB + camera seams) —
identity in Chat does not gray Live; Add in Live places same wc-1 no picker;
scene-with-placement stays gray; identity survives both removals (DB row 1).
WebcamStartupResourceTests single-lock fact asserts CanAddWebcam after adoption.
Docs same commit (ai.md supersession, TASKS.md, HANDOFF.md). 304/304, 0 warnings.
The creator couldn't add a webcam to Live (grayed app-wide) and nothing in the
app explained why. Ground truth from the live DB: one Webcam identity AND one
WebcamSceneConfig in the Chat scene — so the gray was the single-identity rule
working, but the reason was unobservable. This slice makes the webcam a
resource the app validates and locks, mirroring how OBS reserves its devices.
At startup we enumerate the OS once (ValidateWebcamResourceStartupAsync, fired
after LoadLayout, stored as WebcamStartupValidationTask for tests to await):
- 0 webcams -> app runs on, layer inactive, no alarm
- exactly 1 -> attempt CameraManager.AcquireAsync as an app-wide lock; on
failure show a persistent red alert at the bottom of the Layers panel
(WebcamLockAlert + Retry) that re-polls every 5s and clears itself the
moment the camera locks, or on any first real frame
- >=2 -> deliberately no auto-lock; camera selection belongs to the App
Settings dialog (gear) — next slice
CameraManager.IsRunning(deviceId) tells the pass a session already exists
(started OR still starting) so loaded identity configs count as the lock and
the pass never double-acquires. Test seams mirror LayoutPathOverride:
CameraEnumeratorOverride / CameraFrameSourceFactoryOverride so the startup
probe never touches real hardware under test.
Good Dog test: WebcamStartupResourceTests x3 — single-cam locked + app runs on,
zero-cams no-alarm/no-lock, lock-fails -> red alert -> Retry -> clears. Full
suite 304/304, build 0 warnings, scope-check passed.
Docs in-commit: TASKS Open items + ai.md Webcam section + HANDOFF rewrite.
Also corrects the record: 'NVIDIA Broadcast opens the webcam exclusively' was a
suspect-list claim (CameraConflictProbe reads process names only, no handles)
— not restated as fact.
A browser grabbing the C920 kills our reader startup: the camera stays in
MJPG 1920x1080@30 (another app's format) and our OBS-refusal to re-negotiate
under SharedReadOnly contention (`SetMediaStreamPropertiesAsync` throws
'file in use / CaptureMode is SharedReadOnly') leaves it there.
CreateFrameReaderAsync(.., Bgra8) + StartAsync then refuses with
OutputFormatNotSupported — the MJPG-active source only exposes NV12 at the
reader level (clue: startup.log 19:01/19:05 sessions, same hardware that
started YUY2 640x480 fine at 08:52). Fresh launches showed no webcam and
'Add Webcam' failed.
Reader creation is now a per-candidate ladder (ReaderSubtypeCandidates):
Bgra8 for uncompressed cameras (unchanged fast path); NV12 then the
source-default for MJPG cameras — converted in OnFrameArrived like any
non-BGRA frame. Each candidate is allocated AND started under its OWN
catch: WinRT answers an unsupported subtype with a throw (E_INVALIDARG),
not a status, so a single rejected format must degrade to the next
candidate instead of aborting acquisition (creator rule — see MyMistakes
WINRT resource-allocation recipe). Rejections are logged and collected
into the final error.
Good Dog: 4 unit tests lock the candidate ordering (MJPG never Bgra8,
case-insensitive, uncompressed keeps Bgra8 first, unknown/null -> Bgra8).
301/301 green, 0 warnings. [no push]
ty-1841: capture fixed (band ~20 updates/s, no tears) but FramePump stalls
on EVERY iteration (totalMs 21-44, render=full-render split=0 elements=6
dynamic=4) — the render ceiling, ~22-28 composites/s, caps the desktop in a
60fps file. SceneGraph can't help: the live backdrop is element 0 and cannot
be baked (a cached capture goes stale), so the cache lives at the pump.
RenderFull wraps both full-render call sites: BuildFullRenderSignature hashes
the full input identity (options rect, social bar, per-element layout/visual
bits + the frame each element would resolve through the SAME resolver seam,
using array identity + Epoch + CropBounds); unchanged identity reuses the last
composite with one Buffer.BlockCopy (~3ms) instead of a ~30ms re-composite.
Cache buffer is a separate long-lived array, written pre-burn/pre-recycle
(the caller burns the frame counter and recycles scratch AFTER render).
Engagement gated on the 1:1 config (the only deployed tier). Telemetry
surfaces `cache NR/WH` on the 5s stats line.
Same shape as OBS (sources cache their surface, the scene blits on update) —
docs.obsproject.com/backend-design, the pattern this repo cites since the
2026-09-04 paste-cache slice.
Good Dog: FullRenderCache_StaticInputs_RenderOnce_Then_Reuse_UntilInputChanges
(static scene renders ONCE + byte-identical reuse; new frame+Epoch invalidates).
297/297 green, 0 warnings, verify.sh scope-locked (FramePump.cs, FramePumpTests.cs
+ ai.md/HANDOFF/MyMistakes). No push — device re-verify next.
Measure take ty-1824 on the slice-16 build: the downscale fix worked (conv
~47ms, ring allocs 0) but desktop band was still 88% frozen at 6.8 updates/s.
Telemetry isolated the real wall — CreateCopyFromSurfaceAsync readback ~45ms
of each conversion, serialized one-in-flight => ~17/s capture cap. Docs fact:
pool-sized surfaces CLIP, not scale (Microsoft Learn), so readback stays
native; the lever is concurrency.
- MaxConcurrentConversions=3 with pool 2->5 buffers (in-flight frames fit)
- new MonotonicGate (Interlocked compare-exchange): stale OLDER completions
are dropped, never overwrite a newer LatestFrame (mirror of 1742 tear)
- FrameRingBuffer.Rent/ConsumeAllocations now lock; downscale row scratch is
per-conversion locals
- Good Dog test PublishGate_TryPublish_OnlyStrictlyNewerWins; 296/296 green,
0 warnings; docs cited Microsoft screen-capture page + libyuv fixed-point.
Local only, no push.
The 240Hz monitor delivery + one-in-flight conversions + naive double-per-pixel
DownscaleBgra (~150ms/frame under load) froze the desktop layer 90% of take
ty-1742 (6.1 fresh content updates/s, freeze runs to 2.8s; decoded raw-frame
audit). The render stat (33-36ms) was real but moot — the capture CONVERSION was
the wall, and the one torn frame was a ring slot rewritten under the consumer's
read. Reference: WGC delivers at DWM/monitor cadence
(https://learn.microsoft.com/en-us/windows/apps/develop/media-authoring-processing/screen-capture)
and libyuv row-simple/fixed-point scaling
(https://chromium.googlesource.com/libyuv/libyuv/) — the repo's own take-4 rule.
- DownscaleBgra: integer 8.8 fixed-point, shift-only-at-the-end (same two-stage
math as SceneCompositor.Bilinear). ~150ms -> ~5ms per 2.5K->1080p frame.
- 10ms MinConvertInterval: the ~4.2ms 240Hz tail stopped queuing ~150ms of
serialized conversion/s; capacity sits just above the 60/s the pump can use.
- FrameRingBuffer (depth 8, redLine 4): reuse-DISTANCE ring — a buffer is only
rewritten >=4 rents after its last hand-out else fresh-allocated, so a frame a
consumer still holds (session.LatestFrame survives conversions, dispatcher
preview lags) is never read-while-overwritten. Needs no consumer Release API.
- 2s startup.log telemetry: frames/s, conv avg/max ms, skip busy/cadence, ring
allocs — the device take is judgeable numerically.
Good Dog test: Ring_NoLap_ReusesOnlyAfterRedLineRents. 295/295 green, 0 warnings.
C4 (composite Epoch-cached downscale) deferred pending the device re-measure.
Local only, no push.
ty-1723/1726 device takes showed accelerated playback + audio tail cut-off:
a render overrun (~35ms vs the 16.6ms slot) SKIPPED the missed slots (slice 10's
freshness choice), so a 60fps-authoring pump wrote one frame per 35ms into a
60fps container — 1723: 697 frames/11.62s vs 11.84s audio; 1726: 163/2.72s vs
2.93s, video ending 0.21-0.24s early.
OBS never leaves a wall-time hole: the video thread emits one frame per tick and
a lagging producer DUPLICATES the newest frame ("lagged frames due to rendering
lag/stalls" — obs-output.c; "If the video frame queue is full, it will duplicate
the last frame" — docs.obsproject.com/backend-design). The pump's submit is now a
bounded catch-up over the missed slots (while now >= nextTick), fresh on the first,
repeated after — duration == wall, judder not fast-forward. Safe because Channel.
TryWrite never blocks (the take-9 smear was the blocking pipe-write; each emit is
nanoseconds). Burned frame index moved inside the loop: every emitted slot carries
its own +1 (also fixes the old unconditional pre-gate bump that gapped the judge
sequence on non-submitting fast-render iterations).
Good Dog test: Pump_Overrun_Renders_EmitsEverySlot_NotSkipped (60fps, 35ms render
cost, asserts >=0.65 of the wall slots emitted). 294/294 green, 0 warnings.
No push — web/A/V work is commit-local until greenlight.
The ~30Hz CapturePreviewAsync PNG poll capped real cadence at ~20Hz
(35–165ms full-HD encode+decode), so a 60fps widget still juddered at ~1/6
speed. Replaced polling with frame-driven capture of the composition
controller's root visual — the mechanism WebView2CompositionControl and
Flutter's webview_windows use (graphics_context.cc captures the root
surface_ visual via CreateGraphicsCaptureItemFromVisual; reference:
github.com/microsoft/Windows.UI.Composition.WinUI / flutter-internal
webview_windows). Frames now arrive at the renderer's own pace; capture
memory is epoch'd ring reuse + one crop-sized shared WriteableBitmap.
New Services/WebCaptureFrameSource.cs owns GraphicsCaptureItem + free-
threaded Direct3D11CaptureFramePool + session (Straight alpha readback,
per-frame FindContentBounds → CropBounds). WebView2Manager reworked around
per-session composition controllers + one UI-thread Compositor created via
the CoreMessaging CreateDispatcherQueueController P/Invoke (the 19041
projection lacks CreateOnCurrentThread); internal seam ctor
(Dispatcher, Func<string,IScreenCaptureSource>?) for hermetic tests.
CaptureScheduler.cs deleted; the three SetCaptureInterval cadence hooks
removed; InitWebView2() moved from MainWindow ctor to Loaded (a parent
HWND must exist for the composition controller); the hidden WebViewHostPanel
overlay deleted. TransparentBackgroundScript unchanged.
Tests: WebView2ManagerTests reworked — 4 control-size + scheduler tests
dropped, FindContentBounds tests moved to WebCaptureFrameSource, ONE
integration test (Frames_PublishCroppedPreview_And_CoalesceToLatest_CarryingCropBounds)
drives the seam with a FakeWebSource + background-STA DispatcherPump.
Suite 293/293, 0 warnings.
NOTE: composition path NOT yet verified on a device — the take is the
next step. Web work committed locally only (no push per standing rule).
Docs same-commit: ai.md Slice 14 + supersede marker on Slice 11, HANDOFF,
MyMistakes (CoreMessaging DQ + namespace-landmine recipe), TASK 17,
Controls/ViewModels/Services indexes.
Positive offsets still delay the whole mix via the delay line (lip-sync fix);
negative offsets now ARM once at StartLive and drop |N| ms off the pipe's write
head so audio events land earlier when audio runs BEHIND video. Slider relabeled
AUDIO SYNC, Min −500, locked while live/recording (IsEditMode). LayoutStore and
VM clamp to −500..500.
OBS reference for eat-the-head negative sync: https://obsproject.com/kb/obs-studio/buffering-time (negative sync values pull audio earlier by discarding buffered player audio).
Test: StartLive_NegativeOffset_AdvancesAudio_ByDroppingTheStreamHead (6x0.9 head
must be eaten before 0.2 bed reaches the wire).
AudioMixer.Start() begins mic/loopback capture at app startup to feed the
level meters, so both 2s ring buffers fill with pre-live audio. StartLive()
drained from the oldest tail sample, putting every recorded event ~2.2s late
in the audio track (confirmed by clap analysis + cross-correlation on two
takes: +2.11 to +2.22s).
Fix: AudioMixer.StartLive() now runs _micBuffer.Clear() + _loopbackBuffer.Clear()
immediately after the pipe starts, before the drain task runs. Recording now
begins at go-live; the <=10ms in-flight chunk evicted by Clear() is imperceptible.
Regression test: StartLive_DiscardsPreLiveBacklog_SoFirstAudioIsCurrent
saturates the loopback ring with stale 0.8 pre-live audio, then asserts the
wire carries fresh post-live 0.2 (max < 0.3).
Reference (external, per derivative-work rule): OBS 'Audio mixer' keeps its
buffers fed continuously and syncs the stream start timestamp at record time
rather than replaying pre-live capture; a go-live flush of the capture buffer
is the accepted pattern for live tools restarting a stream.
Docs: HANDOFF.md (fix shipped), MyMistakes.md (A/V sync measurement recipe).
silencedetect audio word times cross-correlated with per-frame video motion
(tblend=difference + signalstats) peaks at +22 frames: the 300ms TASK-22
offset plus ~70ms pipeline lag. 370ms reads as one full beat behind during
the ~2.3s pauses. Zeroing the offset targets the residual ~70ms.
- AudioSyncDelay.Configure reallocated/zeroed its buffer every ~10ms tick
(AudioMixer re-reads the UI setting each mix), so any non-zero sync offset
erased the just-written audio -> total silence. Now early-returns when the
delay samples are unchanged. Regression test proven both ways.
- SceneCompositor.BlitContentRaw defaulted cbW/cbH=0 when CropBounds is null
(regression from ed9d7c1) -> webcam blit to an empty rect = gray block.
Default to src.Width/Height. Regression test proven both ways.
- Truncated recordings: rawvideo mux stamps frames at declared 60fps by
arrival; a scene whose first layer is dynamic (hidden elements still count)
kills the bake cache -> full render ~35ms -> ~27fps submitted -> halved
file length. Static scenes bake once (246ms cold, then <1ms) -> 60fps,
full-length (probe + 13:53 take, 301/300 per 5s, 12.46s file from 12.3s
wall). FramePump.ProbeRender names the hot render path on slow frames.
The element-space raster builds on a TRANSPARENT base but BlitContentRaw's
partial-alpha branch applied the opaque-dst source-over blend: color premultiplied
by the sampled alpha, then alpha forced to 255. Pasting that raster saw a==255 and
straight-copied darkened ink over the scene — a recording box that the raw-bitmap
preview (correct alpha) never showed. Transparent margins and opaque content were
unaffected, which is why every take looped on the page/CSS while the capture was
transparent all along (15:51 dumps: alpha max 255, mean ~19, zero 57%).
BlitContentRaw now takes transparentDst; the raster call passes true and writes
straight color + straight alpha so the paste rows (BlendRowOpaque/Weighted) do the
real source-over onto the opaque master. Master paths byte-identical.
ONE integration test PasteCache_SemiTransparentLayer_RevealsBackdrop_NotOpaqueInk:
50%-blue over red reads (127,0,128) fixed vs (0,0,128) buggy — proven both ways
(verified by stashing the fix: fails before, passes after). Clean build, 0 warnings;
22/23 compositor-class tests pass, the sole failure the documented pre-existing
Composite_FullScene_MasterPixels pixel (1380,700).
Alpha-compositing model: standard source-over with producer-cached surfaces, the
OBS/libyuv paste model already cited in ai.md/MyMistakes (rawvideo recipe, row-blit
BLEND_NONE / straight-alpha branches); full story in MyMistakes (RESOLVED entry).
Per the good-dog rule: one integration test, memory updates (MyMistakes/ai.md/
HANDOFF) in the same commit.
The 15:34 take's box interior is the widget's OWN full-canvas opaque paint — a
black void with wide content strips at the top/bottom and a right-edge bar —
arriving AFTER the first-second blank-transparent dumps. A background-color-only
!important wipe (b4bba4b) can't touch it because CSS gradients/backdrops are
background-IMAGE, not background-color.
OBS's fix for this exact symptom is background-image:none (obsproject/obs-studio#6659:
"set the CSS for html and body to background: none !important"). Injection now wipes
background-image:none!important on html,body,html * alongside the color wipe; HTML
overlay art (<img>/DOM/CSS shapes) survives — that is browser-source semantics.
Also re-arms WidgetDumpRemaining=5 ~30s after nav so the next take dumps the real
document INSIDE the recording window (the previous dumps proved blank at +1s and
missed the later backdrop paint).
9/9 WebView2Manager tests, 0 warnings.
The real-widget dumps (12:54/13:50) proved the OLD inline
element.style.background='transparent' injection holds only while the page has
nothing to paint: the capture was alpha-transparent, yet the recording showed a
black opaque box over the whole element rect (1231,679 705x396) once the widget
connected and repainted a container background-COLOR — CapturePreviewAsync always
honors page CSS (MicrosoftEdge/WebView2Feedback specs/BackgroundColor.md), so any
page-painted background wins over DefaultBackgroundColor.
This is the OBS-solved class (all web-uri resources paint their own background):
browser sources use a Custom CSS override, and the decade-validated formula for
arbitrary pages is a pre-parse <style> with 'background-color: transparent
!important' — https://obsproject.com/forum/threads/translucent-transparent-browser-source.59549/
('body { background-color: rgba(0,0,0,0) !important }') plus the div-level variant
for stubborn widgets (woahtech.com OBS custom-CSS guide).
Injection is now an idempotent pre-parse style element wiping background-color on
html,body,html * with !important (outranks every page rule, runs before page parse
via AddScriptToExecuteOnDocumentCreatedAsync). Only background-COLOR is targeted —
background images and widget art survive. Regression test asserts the element-wide
!important form and that the losing inline form is gone.
9/9 WebView2Manager tests, 0 warnings.
The one-shot dump + alpha log was bound to the FIRST capture ever = the initial
about:blank placeholder (alpha=0, rgb=0, 5/5 sessions) — a blind instrument. The
pre-parse transparency injection (1a39b09) is intact but was NEVER verified
(MyMistakes '? VERIFY'), and the 2026-09-10 take still shows a black, opaque
block. Stop guessing: NavigationCompleted for a non-about:blank document now
arms WidgetDumpRemaining=5; the next 5 post-paint captures dump
%TEMP%\ytLive-web-<id>-w1..5.png + shared AlphaStats(min/max/mean/zero%) +
FindContentBounds to startup.log.
The stats line alone names the branch: zero%≈opaque ⇒ the injection did not hold
for this widget's CSS (fix: !important stylesheet / chroma-key); large zero% +
tight bounds ⇒ capture IS transparent and the black lives in the compositor
blend. No new test: WebView2 runtime is not instantiable in the suite and the
re-point is log-only; 8/8 WebView2 tests still pass.
The recorded audio is full-length silent AAC (−91dB, 1124 frames/23.95s) —
the named pipe carried ~9.1MB of zeros the entire take. The mixer's loop
ran, the pipe connected, ffmpeg read it, and the file is full-length
silence. Sources started fine ('Audio: using system default mic...' logged),
no failure callbacks fired, and the existing integration test
(Mix_WithFiltersDuckAndGain_Lands_On_AudioPipe) proves the loop→pipe path
carries real audio when fed — the fault is capture-side.
Added permanent per-5s live-loop telemetry to startup.log so the next take
names the exact stage without new code:
Audio live: pipe connected= dropped writes= micLevel= loopLevel= drained
N/N samples peakMix N (per 5s)
- AudioMixer.FillAndMix now returns (MicRms, MicDrained, LoopDrained) for
the accumulation; StartLive/StopLive log start/stop lines.
- NamedPipeAudioWriter.DroppedWrites: nonzero = audio dropped before ffmpeg
connected (names 'pipe never connected' stage).
Likely root cause: WASAPI loopback captures the default render endpoint —
if audio plays on a non-default device the recording is silently silent.
The fix requires device enumeration + selection (slice 13 candidate).
Suite 290/291 — same sole pre-existing compositor pixel failure.
The recording is 60fps but WebView2 capture was a blind 100ms DispatcherTimer = 10Hz;
each captured web frame repeated ~6x into the file caps web animation at the capture
rate, not the page's (user: 'the animation appears to be too slow').
- New CaptureScheduler (Services/CaptureScheduler.cs): per-session dispatcher timer
that DROPS a tick while a capture is in flight (latest-wins, never queues) — the
guard that makes a higher cadence safe: concurrent full-HD PNG CapturePreviewAsync
calls (~10-30ms each, slow per WebView2Feedback#20) would stack CPU and publish
stale-after-fresh. Effective cadence = max(interval, capture duration).
- Cadence: SetCaptureInterval(33) on record/stream start, (200) idle — applied via
MainViewModel.Streaming.Operations.cs.
- De-throttle the hidden page: shared CoreWebView2Environment created BEFORE
EnsureCoreWebView2Async with --disable-backgrounding-occluded-windows
--disable-renderer-backgrounding --disable-features=CalculateNativeWinOcclusion.
Off-screen WebView2 is a hidden page when the host window is unfocused/covered and
Chromium then parks rAF and clamps timers to ~1s (WebView2Feedback#1172/#3070,
Chrome-88 timer-throttling blog).
- Telemetry: first 30 captures per session log elapsed ms (PNG encode + decode) to
startup.log — that decides whether ~30Hz stays or drops to ~20Hz; the FramePump
drops frames (never time-lapses, slice 10) if UI-thread GC churn starves it.
- ONE test: CaptureScheduler_Drops_Ticks_While_Capture_InFlight_And_Resumes
(deterministic TCS-driven, no WebView2 runtime). Suite 290/291 — sole failure the
pre-existing compositor pixel test.
- Docs same-commit: ai.md slice 11, MyMistakes.md, HANDOFF.
References: https://github.com/MicrosoftEdge/WebView2Feedback/issues/1172https://github.com/MicrosoftEdge/WebView2Feedback/issues/3070https://github.com/MicrosoftEdge/WebView2Feedback/issues/20https://developer.chrome.com/blog/timer-throttling-in-chrome-88
slice 9 made the DURATION right but content still hiccuped; aggregates (301/300, uniform
file PTS) could not see it. Measured root cause: FfmpegEncoder.SubmitFrameAsync BLOCKED
on WriteAsync(8.3MB)+FlushAsync when ffmpeg lagged the pipe, and the burst while-loop
re-wrote that same stale composite per crossed slot — frozen runs.
OBS shape (derivative, wrapped pre-1.0): the encoder queue in libobs/obs-encoder.c —
encoder thread never couples back into the video thread; overflow = dropped data, never
a frozen producer. https://github.com/obsproject/obs-studio/blob/master/libobs/obs-encoder.c
- FfmpegEncoder: SubmitFrameAsync is now an enqueue (ArrayPool copy) into a bounded
Channel (cap 120) drained by its own task; drop-newest + count when full;
StopAsync flushes the queue then EOF (TryComplete). IFfmpegEncoder.DroppedFrames.
- FramePump: ONE fresh composite per iteration (burst loop deleted); worst-submit stat,
stall logger (>2x interval names the stage), dropped/stalls in stats.
- Burned-in 6-digit dot-matrix frame counter (white box, bottom-right) on every composite
— the clock-independent judge replacing the WSL ticker: +1/frame, jumps = counted drops.
- ONE new test Backpressure_QueueOverflow_DropsFrames_AndNeverBlocks (slow-sink fake:
submit never blocks, drops counted, stop flushes exactly submitted-minus-dropped).
- Full suite 290 tests, 289 pass — sole failure the pre-existing compositor pixel test.
- Docs same-commit: ai.md slice 10 (+ encoder/stop-note corrections), MyMistakes point 8,
HANDOFF.
Audio untouched (queued follow-up); web overlay still frozen pending timing closure.
Root cause (measured, not guessed): the take-3 'rebase on overrun' reset
nextTick to wall-now, erasing every missed slot. Pump delivered 215-219/300
per 5s (~43fps) but rawvideo carries no timestamps — ffmpeg muxes by frame
count at -framerate 60, so every recording played fast with honest-looking
stats. A second pacer, ffmpeg -re, throttled the demux separately
('Resumed reading ... after a lag' 0.79s->4.82s).
Fix follows libobs video-io.c (https://github.com/obsproject/obs-studio)
- the video thread never resets its deadline; one frame per interval slot,
a late render repeats content (judder), never skips time:
1. FramePump: count-based emission, while(now>=nextTick){Submit; nextTick+=I}
2. FfmpegArgs: -re removed - the pump is the pacer
Muxed duration is now frame-count/fps == wall time by construction. Covers
game background + webcam (one shared pump). 0 warnings; suite 288/289 -
the one failure (Composite_FullScene_MasterPixels 1380,700) also fails with
this change stashed: pre-existing, untouched, recorded as follow-up.
The widget page paints html/body opaque, so CapturePreviewAsync output had
zero alpha-0 margins — every take since bccdb48 built the crop on 'the
capture is transparent' and never verified it. WebView2 spec is explicit:
'WebView will always honor a webpage's background content' and
DefaultBackgroundColor only shows through pages with no background style
(MicrosoftEdge/WebView2Feedback specs/BackgroundColor.md). The late
ExecuteScriptAsync injection (NavStarting/NavCompleted) ran after page CSS
and lost the fight.
Fix via CoreWebView2.AddScriptToExecuteOnDocumentCreatedAsync — the
documented pre-parse hook ('before the HTML document has been parsed and
before any other script included by the HTML document is run'), the same
mechanism OBS user.css uses. Nav handlers kept as post-load re-assertion.
Restores the take-23/24 stride-correct crop path (my take-25 removal was
wrong — it regressed the bounding box into a solid black box).
Adds one-shot diagnostics: raw capture PNG -> %TEMP%/ytLive-web-<id>.png
plus alpha min/max/mean/%zero and FindContentBounds result in startup.log,
so the next run proves the capture is transparent instead of guessing.
Build 0 warnings, 289/289 tests pass. MyMistakes.md records the full chain.
Slice 10 from today-slices (d1126dd): UVC cameras default MediaFrameReader to their
FIRST media type (YUY2 at crippled fps — C920 720p = 5fps). A 60fps container
then shows a 5-20fps face cam as "every few frames cut out". Fix:
VideoDeviceController.SetMediaStreamPropertiesAsync negotiated to best MJPEG
>=640x360 @>=30fps (<=1280 wide) BEFORE creating the frame reader, with
device-default fallback. Plus a startup.log truth line of the actual agreed media
type so the next diagnosis starts from facts (no more re-deriving the fps).
Build 0 warnings, 289 tests.
Slice 10 from today-slices (d1126dd): the paste cache minted a fresh raster
array per new source frame (webcam ~30 keys/s ≈ 18MB/s LOH churn →
gen2 pauses that ate camera frames). Fix: _elementRasters — re-rasterize
INTO the element's existing array when geometry holds, so steady-state
allocation ≈ 0. The paste cache keys on (array+epoch) still protect correctness;
_elementRasters[element] tracks the element's current raster so stale keys can
never paste a mid-update array. MaxPasteEntries 48→256 (was a leak guard,
not an allocation stream). Regression test:
PasteCache_RingRecycledSources_ReRasterInPlace_WithoutAllocationChurn.
Build 0 warnings, 289 tests.
TASKS.md is now the index (status table, open items, research pointer).
33 files: 32 task files + 1 research facts file. The full take-saga
narrative and all design decisions are preserved verbatim; the catalog
makes the queue readable without opening every task body. Schema and
AGENTS.md updated to reflect the new layout.
User tested: 'didn't work at all, and broke additional crap.' Second failed remedy for
web-source-over-webcam dark composite -> AGENTS.md spin guard: no third guess; next attempt
requires external research (OBS/CEV browser-source transparency in recorded output, cited URL)
plus the blank-page falsifier. HANDOFF OPEN list updated: research-first step added, #11 noted
landed as d35823a.
take-19-2/take-20 'webcam black square under the web widget': the capture was
alpha-cropped (FindContentBounds) and that CROP was fed to the compositor, whose
UniformToFill zoomed the opaque content box to cover the whole element rect the
moment the widget drew any content (idle transparent page = full-frame crop = the
correct viewport, hence take-1-good/take-2-bad). OBS model verified: the page is a
fixed 1920x1080 canvas and the element rect is a viewport onto it — measure with the
alpha crop (preview/selection), hand the composite the FULL canvas on an 8-deep ring
+ Epoch (same identity discipline as camera/screen). Regression test:
Composite_FullCanvasWebSource_TransparentMarginsRevealWebcam (the reveal contract:
margin pixel = webcam, badge pixel = widget).
Roll-forward of today-slices 6fd1d9c onto the slice-8 base, two-loop hunk dropped.
Release counter (per-build GUID read as noise; +1 per commit from git rev-list,
baseline 241 -> #13, generated by GenerateBuildStamp; GUID demotes to startup.log).
Tests pinned to Label/#N >= 13; wordmark display test asserts the Label.
Flash fix (take 14 finding): consumer holds must never outlive depth x source
period — 4 slots at high refresh lap ~27ms vs a <=50ms compositor read, so a
recycled slot flashed its new frame over the lagged old one. All shared rings 4->8
(OBS/overlay precedent for ring discipline).
Camera producer now rotates an 8-deep ring + Epoch instead of a fresh ~3.7MB
array per device frame (110-220MB/s LOH churn); WebView2 capture reuses a canvas
scratch + 8-deep output ring + a reused WriteableBitmap instead of two fresh
arrays + a fresh bitmap per 10Hz tick. Paste cache stays identity-keyed (Epoch).