[XviD-devel] motion compensation->inter4v->BFRAMES->chroma bug?

Radoslaw 'sysKin' Czyz xvid-devel@xvid.org
Thu, 22 Aug 2002 00:10:34 +0930


Hi

I wrote:

> It seems that there is a bug of some sort. It's in motion compensation
> (I'm pretty sure of it), when it handles chroma components in inter4v
> mode AND BFRAMES is #defined.

> If I force all macroblocks to be inter - no bug.
> If I force all macroblocks to be inter4v - no bug. (!)
> If I mix them in any way (even random) - ugly bugs show up. They are
> in chroma only. They dissappear if I force block-based uv compensation.

It was the no-halfpel fix. Inter blocks always had block-based
compensation (so that no-halfpel mode works) but inter4v had
image-based.

The mix does not mix. Don't ask me why. You have to use block based
for both, or image based for both.

Radek