fix: reduce WebGL ReadPixels GPU stalls in video source capture#510
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livepeer-tessa wants to merge 1 commit intomainfrom
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fix: reduce WebGL ReadPixels GPU stalls in video source capture#510livepeer-tessa wants to merge 1 commit intomainfrom
livepeer-tessa wants to merge 1 commit intomainfrom
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Replace requestAnimationFrame + captureStream(fps) with setInterval + captureStream(0) + manual requestFrame(). This ensures canvas drawing only happens at the target FPS rate, eliminating the mismatch between ~60fps draws and lower-rate captures that caused 'GPU stall due to ReadPixels' warnings. Fixes #509
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Closing - wrong codebase. The WebGL issue was on the web platform, not desktop app. |
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Summary
Fixes #509 — WebGL performance warnings ("GPU stall due to ReadPixels") in the Playground 3D view.
Root Cause
useVideoSource.tswas drawing video frames to a canvas viarequestAnimationFrame(~60fps) whilecaptureStream(fps)captured at a lower rate (e.g. 15fps). This mismatch caused the browser to perform synchronousReadPixelscalls at ~60fps, triggering GPU stalls.Fix
captureStream(0)(manual frame capture mode) instead ofcaptureStream(fps)requestAnimationFramewithsetIntervalat the target FPS ratevideoTrack.requestFrame()after each draw, so canvas readback only happens at the intended capture rateThis reduces canvas readback frequency from ~60fps to the target FPS (default 15), eliminating the GPU stall warnings.