[Ffmpeg-devel] Threading in libavcodec

[Guillaume POIRIER]

Hi,

On 1/23/06, Michael Niedermayer <michaelni at gmx.at> wrote:
> Hi
>
> On Mon, Jan 23, 2006 at 10:34:35AM +0100, Mathieu Monnier wrote:
> > >>> Libavcodec can optionally be compiled to use multiple threads.
> > >>> This improves encoding speed on multiprocessor machines.
> >
> > >> And lowers quality.
> >
> > > Or increases bitrate.
> >
> > >> XviD implements multithreading without losing any efficiency, and
> > >> scales well, while lavc, from what you're saying, doesn't.
> >
> > > I didn't say it, Rich did. Rich is, as we all know, obsessed with
> > > image quality.
> >
> > Anyway, I rather wanted to put the emphasis on the fact that threading
> > can be implemented in a way that doesn't reduce the coding efficiency,
> > as XviD proved it.
>
> wait, you can always implement anything with 2 threads what can be done
> with 1 binary identically, the question is how fast it is
>
> its always a tradeoff between speed, quality and complexity
> now i wanted to look at xvid, but i cant find any multithreaded code in cvs
> am i blind? IIRC there was some patch for multithreaded motion estimation
> on the xvid-dev list, is that what you are talking about?

Yes, that's the one you can find here:
http://forum.doom9.org/showthread.php?p=756173

Guillaume
--
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MPlayer's doc is offline. Find some fresh one here:
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