[Ffmpeg-cvslog] CVS: ffmpeg/libavcodec snow.c, 1.68, 1.69 avcodec.h, 1.436, 1.437

[Jeff Clagg]

On Wed, Dec 28, 2005 at 03:32:11PM -0800, Corey Hickey wrote:

> Besides that, what is *cmp=12? It doesn't seem to be documented.

Quoth mplayer's DOCS/tech/snow.txt:

 * cmp, subcmp, mbcmp
   Set the comparison function, default: 0 (SAD).
   useful values = 0 (SAD), 1 (SSD), 11 (5/3 wavelet), 12 (9/7 wavelet).
   Experience shows that SSD is the best most of the time, while SAD is
   slightly better the remainder of the time.

[snip]

Then, at the end of that document:

   v4mv and the wavelet cmp functions are theoretically good, but in
   practice won't work well until we get OBMC-aware motion estimation.

   In short:
   The best options in almost all cases are
   vcodec=snow:vstrict=-2:vqscale=$N:pred=0:cmp=1:subcmp=1:mbcmp=1:qpel