[XviD-devel] Decoder performance

[Edouard Gomez]

Hello,

I am  working hard on making  good xvid devapi4 support  for linux apps.
Elcabesa released his  sources for mencoder/mplayer a long  time ago and
i'm actually working  on the mplayer decoder module  (the encoder module
is already finished and fully functional).

I  must admit  i had  a very  bad surprise  looking at  XviD performance
compared to libavcodec... 

I ran mplayer with this cmd line:
mplayer (-vc xvid) -vo null -nosound -benchmark matrix-trailer.avi

XviD CSP YV12/I420:
BENCHMARKs: VC: 77,105s VO: 0,020s A: 0,000s Sys: 1,529s = 78,654s

XviD CSP INTERNAL Buffers (that's a bit faster):
BENCHMARKs: VC: 68,771s VO: 0,018s A: 0,000s Sys: 1,732s = 70,520s

libavcodec (that's a lot faster):
BENCHMARKs: VC: 27,239s VO: 0,014s A: 0,000s Sys: 3,127s = 30,380s

I  remember  XviD not  being  so  slow in  the  near  past,  is there  a
significant change  in the  decoder that  could make it  so slow  now (2
times slower than libavcodec) ? 

I'm probably  going to  do some profiling  to spot the  bottlenecks, but
giz, two times slower...

--
Edouard Gomez (surprised)