[Ffmpeg-devel] Re: [RFC] mpeg2 422 encoding.

Michael Niedermayer michaelni
Sat Apr 1 04:32:50 CEST 2006


Hi

On Fri, Mar 31, 2006 at 08:37:43PM -0500, Rich Felker wrote:
> On Sat, Apr 01, 2006 at 03:03:37AM +0200, Baptiste COUDURIER wrote:
> > Baptiste COUDURIER wrote:
> > >[...]
> > 
> > Ok, a bit more. It works correctly for intra. It produces picture for P
> > and B frames, though containing artifacts like blue/red blocks.
> > Bistream is correct.
> > 
> > Im digging more into the code. It may be related to motion estimation.
> > Michael, does motion estimation work in 422 chroma format ? If it is,
> > then Im a bit lost here.
> 
> AFAIK motion estimation ignores chroma channels unless you override it
> with a special option.

exactly

also motion estimation doesnt matter, set all MVs to arbitrary valid vectors
and it should still work, i mean quality and bitrate will suck but there
shouldnt be any blue or red blocks

here are a few random ideas ...
try -debug 16384 it will vissually show MB types
try -vismv ... it will show motion vectors
try to force vectors or MB types to specific ones
try valgrind
do P frames with just intra blocks work?
do P frames with just inter blocks with MV 0,0 work?
....


[...]
-- 
Michael





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