[MPlayer-dev-eng] audio & video encoding (stream problems?) very slow

[D Richard Felker III]

On Sun, Feb 17, 2002 at 12:20:07AM -0800, Charles Henrich wrote:
> Okay, so I have audio/video capture working with this brooktree driver on
> *bsd.  If I capture just straight video I cn capture to disk w/ 384x288 at 25fps
> divx with no frame loss, no issues.  At 768x576 I can get about 24fps to disk
> if I do -ovc copy.
> 
> This is great.  However, If I enable audio capturing, the performance goes
> into the toilet.  I can only get 2-5fps, I see DEMUXER errors (that I dont
> really understand), and I get all sorts of headaches.  This happens with lame
> encoding, as well as -oac copy and -oac pcm.  This tells me there is something
> "Wrong" in the stream handling code.  Anyone have any ideas/suggestions?

are you using -oac copy, or mp3 encoding? if it's mp3, my first guess
would be that lame is JUST THAT SLOW. it's really quite bad in terms
of speed. try -lameopts br=128:cbr:q=9 (constant bitrate, lowest
quality, which is still considerably better quality that most mp3
encoders) and see if that helps. alternatively, use -oac copy.

if you still have problems, it's probably your audio capture code. in
any case, i would experiment with -oac copy -- that way you don't have
as many unpredictable factors coming in.

rich