[MPlayer-users] ffmpeg mpeg1 encoding test

[Fabio Papa]

On Saturday 20 September 2003 00:38, Michael Niedermayer wrote:
> [Automatic answer: RTFM (read DOCS, FAQ), also read DOCS/bugreports.html]
> Hi
>
> On Friday 19 September 2003 11:50, Fabio Papa wrote:
> > [Automatic answer: RTFM (read DOCS, FAQ), also read DOCS/bugreports.html]
> > Hi all,
> > could someone with encoding experience try a little experiment, just to
> > make sure I'm not the only one with this problem?
> > Try compressing any video you wish to mpeg1video using lavc, whatever
> > parameters you think is necessary, to an avi file using mencoder.
> > It should play correctly and should output something like:
> >
> > VIDEO:  [mpg1]  480x576  24bpp  25.000 fps  779.5 kbps (95.2 kbyte/s)
> > VIDEO:  MPEG1  480x576  (aspect 1)  25.000 fps  779.5 kbps (97.4 kbyte/s)
> >
> > Then try to extract the video stream using ffmpeg, since it's the only
> > way (at least that I know of):
> >
> > ffmpeg -i avifile -vcodec copy -f rawvideo mpgfile
> >
> > then play that file. What I see is this:
> >
> > MPEG-ES file format detected.
> > VIDEO:  MPEG1  480x576  (aspect 1)  25.000 fps    0.0 kbps ( 0.0 kbyte/s)
> >
> > Obviously something is very wrong here. This behaviour has started since
> > after 0.4.7 ffmpeg got out. Needless to say I cannot use those videos in
> > any DVD author app. It seems to me like mpeg1video is relying on the avi
> > container for the kbps/sec value, and doesn't have one of its own.
> > Can somebody throw some light in this?
>
> try to set -lavcopts vrc_maxrate=...
> (and yes feedback is welcome ...)
Yes! That was it! FFmpeg from 0.4.7 on pretends the maximum bitrate to be set, 
otherwise it produces handicapped files. I must say that they could have done 
it in a thousand other ways other than producing a bad file, but I don't 
care, since now it is working.
Many, many thanks!


>
> [...]

-- 
Fabio Papa
Engineering division
Machining Centers Manufacturing S.p.A.
viale F. e G. Celaschi 19 - Vigolzone (PC) Italy