[MPlayer-dev-eng] Make ffmpeg MPEG1/2 decoder the default?

[Rich Felker]

On Mon, Feb 18, 2008 at 10:20:24PM +0100, Diego Biurrun wrote:
> On Mon, Feb 18, 2008 at 12:47:52PM -0500, Rich Felker wrote:
> > On Mon, Feb 18, 2008 at 06:17:42PM +0100, Diego Biurrun wrote:
> > > On Mon, Feb 18, 2008 at 06:12:29PM +0100, Reimar Döffinger wrote:
> > > > On Mon, Feb 18, 2008 at 10:18:38AM +0100, Diego Biurrun wrote:
> > > > > On Sat, Feb 16, 2008 at 03:38:36PM +0100, Reimar Döffinger wrote:
> > > > > > libmpeg2 may be still slightly faster (though probably not on the newer CPUs),
> > > > > > but it is quite crash-happy and otherwise buggy (see also 34582.mxf in
> > > > > > incoming).
> > > > > > Thus I am for making FFmpeg decoder the default, any objections?
> > > > > 
> > > > > I'm not too convinced of this since libmpeg2 was still faster the last
> > > > > time I tried and now we have a pending patch with further speedup.  I
> > > > > propose running benchmarks on many different CPUs instead.  Let's find
> > > > > out which one really is the fastest.  Maybe we can motivate somebody to
> > > > > try making FFmpeg speedier...
> > > > 
> > > > My benchmarks say it completely depends on the CPU, though the speed on
> > > > the old Athlon would be more relevant in practice (though I doubt that many
> > > > are still in use).
> > > 
> > > Why aren't you using -vo null like we have always done for these
> > > benchmarks?
> > 
> > Because it hides all sorts of performance data which is relevant. I
> > care about the performance difference between decoders when memcpy to
> > video memory and execution of vo code is contending for the cache, not
> > in some idealized-but-irrelevant environment with no vo.
> 
> OK, so let's do this properly: We need a standard command line that
> everybody uses for testing, a set of sample files that exercise
> different parts of the decoders and some testing methodology.
> 
> I propose the following command lines:
> 
> -vc ffmpeg12 -benchmark -nosound -quiet -vo null
> -vc ffmpeg12 -benchmark -nosound -quiet -vo x11
> -vc mpeg12 -benchmark -nosound -quiet -vo null
> -vc mpeg12 -benchmark -nosound -quiet -vo x11

x11 is a very bad choice. It will invoke vf_scale which is extremely
unusual to have loaded and NOT the norm for watching video. The vo
should be something sane yuv-based, or even a dummy yuv vo driver
which memcpy's the data to a fixed buffer in system memory and
supports slices and dr..

Rich