[FFmpeg-user] Bug in FFMPEG Alsa?

[christina zou]

Hello,

I have two alsa commands:

1. ffmpeg -f alsa -acodec pcm_s32le -i mic_sv temp.wav

2. arecord -Dmic_sv -c2 -r48000 -fS32_LE -twav temp.wav

Command 1 takes 95% CPU and produces stuttery, clicky unusable audio.

Command 2 takes 5% CPU and produces perfect audio.

I'm on a Pi Zero. I compiled FFMPEG with ALSA support.

After a long chat in FFMPEG IRC, we believe there is something wrong with
the way FFMPEG waits for ALSA packets. At the very least, FFMPEG waits for
ALSA packets differently than arecord does.

How should I proceed?

Report logs for both commands are attached.

Thanks very much,
Christina
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