[FFmpeg-devel] [PATCH] More H.264 decoding speed tweaks

[Loren Merritt]

On Fri, 20 Jun 2008, Jason Garrett-Glaser wrote:

> Interesting--I will have to do more benchmarks since I'm reverting
> Loren here ;)  Its possible the dc_add may be more useful for some MB
> types than for others.

Not sure about MB types, but it does depend on bitrate. Not only the % 
but also the absolute amount of time saved by dc_add increases at low bpp.
dct size didn't measurably affect the results.

(decoding times in seconds, stddev of 10 runs)
1280x528 qp12 10153kbit  svn: 135.70 +/- .13  patched: 137.65 +/- .15
1280x528 qp18  3672kbit  svn: 104.53 +/- .12  patched: 107.37 +/- .15
1280x528 qp24  1408kbit  svn:  68.98 +/- .09  patched:  72.50 +/- .10
1280x528 qp30   653kbit  svn:  54.68 +/- .07  patched:  58.57 +/- .07

--Loren Merritt