[XviD-devel] XVID Bframe AVIs and ffmpeg decoding

[Michael Niedermayer]

Hi

On Monday 13 January 2003 13:54, Christoph Lampert wrote:
> On Mon, 13 Jan 2003, Michael Niedermayer wrote:
> > Hi
> >
> > On Monday 13 January 2003 12:33, Christoph Lampert wrote:
> > > On Mon, 13 Jan 2003, Christoph Lampert wrote:
> > > > errors and image distorsion (or other values, often 0,00000).
> > > > When I create a raw M4V stream and embed them  into MP4 container, I
> > > > _don't_ get these messages when playing, and the image is fine.
> > >
> > > Oh, great! Now it happens with raw encoding, mp4creator and .MP4, too.
> > > Still no ideas what causes it... :(
> >
> > at first quick look, its wrong stuffing bits, combined with bad luck
> > (normally ffmpeg/lavc detects & works around it)
> >
> > u can try mplayer with "-lavdopts bug=0" to force bugfree type decoding,
> > it fails
> > or try mplayer with "-lavdopts bug=16" to force padding/stuffing bug type
> > decoding, it works
> >
> > btw, could it be that xvid doesnt add stuffing bits if the last bit ends
> > at byte aligned boudary?
>
> Yes, that's it! I'll a commit a patch... It has to be done just before
> VOP/VOL/VO startcodes, not between other structures, am I right?
dunno about VOP /VOL/VO perhaps its not needed there but it certainly is 
needed at the end of slices & end of the picture

if its not done then detecting the end of slices is somewhat tricky and 
reverse decoding of RVLC would be impossible but noone uses RVLC so the later 
doesnt matter ...

[...]

Michael