[Libav-user] High CPU load for parsing MPEG-TS

[Michael Niedermayer]

On Thu, Nov 17, 2011 at 08:48:15PM +0000, Andrea3000 wrote:
> I use latest git version of FFmpeg API as parser in my 
> media player app (not as decoder).
> It works great with every format/codec/muxer/ecc..
> 
> The only annoying thing is that with around 50%-60% of 
> MPEG-TS file that I've tested, CPU stays over 60% just 
> for parsing data.
> If I remux the movie file with tsMuxer 
> (without re-encoding and using the same container), 
> the problem disappears and CPU usage is below 5%.
> 
> I've never seen this issue with FFmpeg-mt versions 
> prior to 0.6. I don't know about versions in beetwen 
> because I jumped from FFmpeg-mt 0.5.x to latest
> FFmpeg git repository.
> And this is not the only strange thing. If I don't allow 
> FFmpeg to seek through the file to correctly allocate 
> AVFormatContext and to identify all the available 
> streams, it does find only the first streams 
> (main video track and audio tracks) and not all the PGS
> subtitles tracks and secondary video track, but the 
> high CPU usage problem does not appear!
> 
> What is going on here? Am I missing something? 

well, if you can find out (with git bisect) which revission introduced
the cpu load problem then its likely it can be fixed

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

I have never wished to cater to the crowd; for what I know they do not
approve, and what they approve I do not know. -- Epicurus
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