[XviD-devel] DivX5.03 rounding?

[Christoph Lampert]

On Thu, 6 Feb 2003, Christoph Lampert wrote:
> > 
> > That's OK, we do it in 8x8 as well. MODE_DIRECT_NO4V is not set in
> > qpel mode, so motion compensation to be performed on 8x8 blocks.
> 
> Ahhh... that's tricky! Of course I just read the "switch" and thought 
> DIRECT_NO4V was set. 
> 
> Is decoder doing this as well? There is a call in bf_interpolate_mbinter()
> 
> if(dec->quarterpel) {
>                 if((pMB->mode == MODE_INTER || pMB->mode == MODE_INTER_Q))
>                         interpolate16x16_quarterpel(dec->cur.y,forwar...)
>                 else {
>                         interpolate8x8_quarterpel(...)
>                         interpolate8x8_quarterpel(...)
>                         ...
>                 }

Okay, I found it. For pMB->mode is never MODE_INTER, because it's
hardcoded to MODE_INTER4V before calling of the routine. 

So once again, XVID does it right, and the other ones don't.

gruel