Audio capture: stop blocking main thread, send raw PCM buffers #8

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opened 2026-10-03 09:24:07 -04:00 by adam · 1 comment

adam commented

2026-10-03 09:24:07 -04:00

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Problem:

Linux: execSync('pw-dump') up to 25× plus execSync('pw-link …') per port on the main process → UI freezes during share start.
Windows: every PCM chunk is converted with Array.from(pcmData) before IPC — huge per-chunk allocation/serialisation.
onAudioPcmData in preload adds an ipcRenderer.on listener per call and returns no unsubscribe, so listeners pile up across shares (pwa side tracked separately).

Fix:

Use async execFile (promisified) for pw-dump/pw-link.
Send the Buffer/Uint8Array directly.
onAudioPcmData returns an unsubscribe function; pwa calls it on teardown.

Where: src/audio.js:32,180-250,262-266, preload.js:12-14

**Problem:** - Linux: `execSync('pw-dump')` up to 25× plus `execSync('pw-link …')` per port on the main process → UI freezes during share start. - Windows: every PCM chunk is converted with `Array.from(pcmData)` before IPC — huge per-chunk allocation/serialisation. - `onAudioPcmData` in preload adds an `ipcRenderer.on` listener per call and returns no unsubscribe, so listeners pile up across shares (pwa side tracked separately). **Fix:** - Use async `execFile` (promisified) for `pw-dump`/`pw-link`. - Send the `Buffer`/`Uint8Array` directly. - `onAudioPcmData` returns an unsubscribe function; pwa calls it on teardown. **Where:** `src/audio.js:32,180-250,262-266`, `preload.js:12-14`

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2026-10-03 09:24:07 -04:00

adam referenced this issue from a pull request that will close it,

2026-10-03 11:52:09 -04:00

Audio capture: async PipeWire calls, raw PCM, unsubscribe (#8) #10

adam referenced this issue from a commit

2026-10-03 11:52:11 -04:00

fix: async pw-dump/pw-link, raw PCM buffers, unsubscribable onAudioPcmData (#8)

adam commented