[MPlayer-users] libavcodec - encoding with bframes

[Michael Niedermayer]

Hi

On Wednesday 05 June 2002 09:59, Michal Seliga wrote:
> [Automatic answer: RTFM (read DOCS, FAQ), also read DOCS/bugreports.html]
> I uploaded testfile&outputs to ftp.mplayerhq.hu/MPlayer/incoming/,
> find file named:
>
> libavcodec-broken_divx_encoding_with_bframes.tar.bz2
>
> complete bugreport included in archive
>
> Mplayer is CVS version from 4.6.2002
> libavcodec is CVS version from 4.6.2002
> Mandrake 8.2
> gcc 3.0.4
>
> problem: when I compress test.mpg with libavcodec to divx with no B frames
> it looks good. If I use B frames there is green stripe at the left side of
> image. It always worked well with mplayer version 0.90pre4 and libavcodec
> included in its archive...
what -vo do u use, i cant see any green stripe and the width is not a 
multiple of 16, some vo drivers have problems with that ...

>
> btw. is it possible to generate divx video stream with B frames compatible
> with windows divx? Because almost everyone has divx5 installed and it is
> hard to persuade people to install ffdshow codecs... (Once I got reply that
> divx5 is buggy but maybe it is possible to workaround its bugs somehow...).
for decoding we do workaround divx5 bugs, but for encoding we dont, it would 
be foolish imho to support creating more broken mpeg4 files

>
> And if divx video stream has B frames, shouldn't it have DX50 code in avi?
dunno, mpeg4 is mpeg4, it shouldnt matter

>
> And can someone tell me what does this strange divx features mean, what is
> their advantages (speed, size, quality...) and if they are supported by
> libavcodec (both encodeing and decoding)? I mean Quarter Pixel and GMC.
qpel & gmc decoding is supported in libavcodec, encoding is not

[...]

Michael