[MEncoder-users] Encodes for slow laptop

[Diogo Franco]

Em Qua, 2008-06-11 às 10:24 -0700, Stella-Terra Clemens escreveu:
> Yeah, unfortunately, though the drivers are TECHNICALLY accelerated, it's an
> onboard video card and I get 60 FPS from glxgears.  I can try the different
> VOs later, but I'm fairly confident anything GL related is going to go up in
> smoke.
> I'll check out the stuff with the adapters, but, again, support for this
> video card isn't that great, so I have low confidence of improvement.
> I have "-lavdopts skiploopfilter=all" in my .mplayer/config file.
> As for libavcodec and xvid being the same: that puzzles me.  So, as I
> understand it, they're both just different applications that encode video
> into MPEG-4 Part 2, wheras x.264 encodes into MPEG-4 part 10.  In which
> case, why were people earlier saying there would be a difference in the
> speed of decoding libavcodec encoded files?  Also, are there any other
> encodings (aside from MPEG-4 Parts 2 and 10) that I should try?  Obviously
> there's MPEG-1 and MPEG-2, but those are the only 4 encodings I know of.
> Thank you,
> Stella

Well, mplayer always uses 'ffodivx' to decode MPEG-4 part 2 video so I
think that the decoding speed only changes if it has to do more
corrections on one than on the other.

For the codecs, there is SNOW, but the format isn't fixed yet and the
videos may stop working anytime. Also, to use it you have to pass
':vstrict=-2' to lavcopts. There is H.263, a very light codec used on
cellphones but it forces you to use some fixed resolutions. Sorenson
Video 1 (svq1), Windows Media Video 7 and 8 (wmv1 wmv2) are other
options. I did not test any of those video formats except for snow, so I
can't recommend any of them.

Don't try theora, at least not now. The video quality is horrible even
with a very low fixed quantizer. Dirac is broken too and you don't have
a container to put it.

For the container, prefer mkv or nut. mkv has a better compatibility.
Maybe mp4 if you stick with MPEG codecs. The performance that is related
to containers is just disk speed and space; but some containers like avi
or ogg have a big overhead and sometimes that may lower disk
performance. You are stuck with avi when using mencoder with b-frames,
but you can re-mux the files later with ffmpeg or any other good tool
like mkvmerge or MP4Box.

Also, as your CPU is a bit slow, did you benchmark audio performance
too? Try vorbis, flac, mp2, mp3, wmav1, wmav2 and aac; if disk space is
a problem use Nero's encoder to encode AAC because faac's encoding is
kinda bad.