[Libav-user] Noise while seeking in mp3 files.

[Prunk Dump]

2011/8/26 Ole Dittmann <ole at madhat.de>:
> I found the same thing with aac and wmv.
> Already reported it a few months ago.
> But that was during the whole ffmpeg/libav incident so it probably got
> wasted.
> Just took your post as reason to repeat the ticket:
>
> https://ffmpeg.org/trac/ffmpeg/ticket/420
>
>
> Am 25.08.2011 13:04, schrieb Prunk Dump:
>
> When seeking in a mp3 file, the decoder produce a noise depending of
> when the seek is done. This is illustrated in the attached file
> "audioBitStream.jpg".
>
> ->If I seek to timestamp 0 while playing “hight” sound, a noise is
> clearly visible when I restart decoding (see first stereo stream :
> dump10noise.raw)
>
> ->If I seek to timestamp 0 while playing “silence”, no noise is
> produced (see second stereo stream : dump10clear.raw)
>
> So it seems that  avcodec_flush_buffers doesn't completely flush all
> the buffers of the codec. We see that it keep track of the last
> decoded sound.
>
> So is this a bug ? Or it's me that have I missed something?
>
>
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I have updated the ticket with my own demonstration program. This bug
is really annoying. It's strange that it appears in the widely used
mp3 codec !