[XviD-devel] API3 -- hinted mv & bframes

[Radoslaw Czyz]

Hi

> 2. extend the hint bitstream to support bframes.

I'm not really sure it's going to work - a bit different reference
picture of the second pass has a high chances of affecting mode
decision, so hinted me can look _really_ much worse for b-frames.
I can't be sure, of course.

>    gruel,syskin, what mb[x]->fields do we need for bframes??

In the current ME code:
pMB->mode
pMB->mvs[4] //for motion compensation only, all modes except
            MODE_BACKWARD.
pMB->b_mvs[4] //for motion compensation only, all modes except
            MODE_FORWARD
pMB->pmvs[4] // only the first vector of the array, only forward and
             interpolate modes
pMB->b_pmvs[4] // only the first vector of the array, only backward and
             interpolate modes. note that b_pmvs[1..3] is NEVER used
pMB->deltamv // only for direct mode

In my ME code:
pMB->mode, pMB->mvs[] and pMB->b_mvs[] as above
pMB->pmvs[4] for all modes
the end

Please also note that in my HintedME search (which is a simple search
based on a hinted motion vector) pMB->pmvs[] are not used, but
computed just like in normal ME search.

Radek