[FFmpeg-cvslog] r22773 - trunk/libavcodec/motion_est.c

Jason Garrett-Glaser darkshikari
Fri Apr 2 13:42:49 CEST 2010


On Fri, Apr 2, 2010 at 4:06 AM, michael <subversion at mplayerhq.hu> wrote:
> Author: michael
> Date: Fri Apr ?2 13:06:29 2010
> New Revision: 22773
>
> Log:
> Reduce the size of the bidir refine hashtable from 4096 to 256 and
> change the hash function to something more sane and simple.
> about 1/3 faster, no meassureable change in psnr or size and i gues
> its even same md5 with my test file but i forgot testing that.

x264 uses a bitfield (one bit per slot) for [8][8][8] instead of
[8][8][8][8], which should be enough to provide these gains without
introducing costly multiplies.

Maybe try that instead?

Also, I hereby LGPL the memzero_aligned_mmx and memzero_aligned_sse
functions in x264 if you want to use those for faster zeroing of the
hashtable.  They're utterly trivial though.

Dark Shikari



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