[XviD-devel] Buggy Divx5?

[Christoph Lampert]

On Wed, 6 Nov 2002, Michael Militzer wrote:

> > Btw. do you know what causes it (what the bug is)? Then we might add a
> > "workaround" mode. I think compatability to DivX5 (even if that is
> > buggy) is still important to many users.
> 
> I don't really know why DivX5 cannot correctly decode INTER4V+qpel vids, but
> anyway it makes no sense at all to imitate DivX bugs (and generate
> non-compliant videos then) just to make XVID output playable with DivX (and
> I hope you weren't really considering this option). Simple solution is to
> not use 4MV mode, but those videos still won't play correctly with DivX5
> because of DivX's wrong chroma rounding...

No, I wasn't considering creating buggy MPEG-4, but creating valid MPEG-4 
files that only use that subset that DivX5 handles correctly. 
Completely switching of INTER4V+Qpel is one way for that, but maybe 
inter4v at halfpel/fullpel works correctly, only at qpel it doesn't or
vice versa. Something like that...

But it's not very important, of course... I was just curious about DivX5
internals...

gruel