Re[2]: [XviD-devel] direct mode predictor error

[Radoslaw Czyz]

Hey

>> >There also is no 132 frame i-frame rule. There is a "132 frame INTRA-block
>> >rule". Every macroblock must not be INTER encoded for more than 131 blocks
>> >in a row. Then it has to be INTRA coded. But if the INTRA block is in
>> >INTER or INTRA frame doesn't matter. At least that's how I read the
>> >standard:
>> 
>> okay, okay, a minor typo.

> Yes, but with consequences... unfortunately it would be quite a lot of
> (two-pass) work to distribute the INTRA-blocks cleverly, and a simple
> counter in a still scene would indeed lead to 90% INTRA-blocks within one
> frame after 132 frames. :(
> Maybe lets support this "feature" (flag XVID_REFRESH132) for a
> "hardware compatability" mode and apart from that ignore it?

Hey, I've been thinking - is it difficult to have less than 132 inter
frames before intra? If a movie is 25fps and we put only one B frame
between every P frame, that gives us an effective rate of INTER blocks
of 12.5 fps. You'll need more than 10 seconds before you reach 132
inter blocks one after one... All we need to do is to put some B
frames to comply with the limitation.

Radek