[Ffmpeg-devel] [PATCH] Snow mc_block mmx optimization
Sun Mar 26 23:58:51 CEST 2006
On Sun, Mar 26, 2006 at 11:21:08PM +0200, Oded Shimon wrote:
> On Sun, Mar 26, 2006 at 11:13:37PM +0200, Michael Niedermayer wrote:
> > first comes the spec/algo then comes the optimiation
> > whats the speed & PSNR/bitrate of the common test videos like forman if we
> > would always use the mc_block() code and never the h.264 code?
> No idea. How do I test this, remove all if's there and use mc_block ?
By a quick hack attempt of just removing everything and leaving only
mc_block in pred_block, I got about 10% speed loss in yblock (with my
optimized mc_block) :
(old is h264 and mc_block, new is pure mc_block)
old: 29762 dezicycles, 261510 runs, 634 skips ( 778322746 total) in add_yblock
new: 38523 dezicycles, 261584 runs, 560 skips ( 1007706523 total) in add_yblock
old: 47347 dezicycles, 1048264 runs, 312 skips ( 4963238600 total) in add_yblock
new: 55883 dezicycles, 1048303 runs, 273 skips ( 5858310153 total) in add_yblock
old: 55193 dezicycles, 523788 runs, 500 skips ( 2890955984 total) in add_yblock
new: 65341 dezicycles, 523849 runs, 439 skips ( 3422894211 total) in add_yblock
as for psnr vs. bitrate:
old: 2369047 bytes PSNR: Y:44.64, Cb:46.19, Cr:46.30, All:45.11
new: 2372830 bytes PSNR: Y:44.62, Cb:46.15, Cr:46.28, All:45.09
This is all about as quick and dirty a test as possible, just a single
file test, and maybe mc_block can be optimized further, I dunno.
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