On weighted B-Frames

[SirDavidGuy]

I'm not sure in which forum this belongs, but I think it's here.

B-Frames have a weighted interpolation, but it does not have anything to do with the distance from the anchor frames (eg. For fades).

Why?

Would it help with encoding a noisy source?

[-h]

Goodness.

I can't check the spec right now, but from memory B-frame interpolation in MPEG-4 isn't weighted at all, it's just the rounded average between two reference values.

It might help fades if it was, but if a fade is correctly encoded by the motion estimation engine it will hardly increase bitrate at all, since the fade can be completely described by the DC values and thus take few bits to store.

-h

[SirDavidGuy]

Mpeg-1 B-Frames (which I was talking about, in a series of revisions, I guess I deleted it [or maybe only thought I had it]) are weighted.

I couldn't see any good reason for it.