[FFmpeg-devel] MPEG-2 Acceleration Refactor

Ivan Kalvachev ikalvachev
Sun Jun 17 12:59:59 CEST 2007

2007/6/17, Michael Niedermayer <michaelni at gmx.at>:
> Hi
> On Sat, Jun 16, 2007 at 06:44:21PM -0700, Greg Hulands wrote:
> > Based on the START/STOP_TIMER stuff showing the patch is actually
> > faster I have tidied the patch a little more and removed the function
> > prototypes to the _fast functions at the top of the file.
> >
> > If there are any other problems from stopping this getting committed,
> > please let me know.
> yes, why is it faster now and was slower before?

I think nothing has changed. The functions alone are faster, the
decoding as whole is slower ;) It's just one of the miracles of

My guess is that placing START/STOP_TIMER inside the functions in
question changed the way they are optimized.

As of why the new vs. old is slower, I think that assembler output
would give us more clues.

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