[FFmpeg-trac] #1049(undetermined:new): bad sound (clicks + low pitch / slower speed)
FFmpeg
trac at avcodec.org
Sat Mar 10 13:45:36 CET 2012
#1049: bad sound (clicks + low pitch / slower speed)
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Reporter: goblin | Owner:
Type: defect | Status: new
Priority: normal | Component:
Version: git-master | undetermined
Keywords: aac | Resolution:
Blocking: | Blocked By:
Analyzed by developer: 0 | Reproduced by developer: 0
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Comment (by goblin):
Uploaded a sample to incoming/tkt_1049_low_pitch_sound.mkv
Couple of extra things to note:
* I have two sound cards, the built-in HDA Nvidia, and a PCI Sound Blaster
Audigy
* The order of them is random after each boot - so yesterday when I tried
ffplay I had the buggy sound OK out of the Nvidia card, but after today's
boot it was all quiet because it chose the Audigy - even though I always
have default as Audigy in my ~/.asoundrc. So today to reproduce the bug I
had to use AUDIODEV=hw:0 envvar to force SDL to use the Nvidia card.
* Again please note that the low pitch sound / clicks occur only on the
Nvidia card when using ffplay - the Audigy card is all silent (no sound).
This doesn't happen with mplayer: with mplayer, I can use any card and
still hear the bug occur on both. Unless I use mplayer -ac faad, in which
case the sound is fine on both cards.
* Please also note that the mkv has 6-channel audio in 5.1 - both of my
cards are only doing stereo (as I only have stereo speakers connected). It
might be trying to play all 6 channels together through only 2 channels,
which might explain why there's extra data and why the sound appears
"slower".
--
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/1049#comment:2>
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