[XviD-devel] Changes to get_pmv2

Radek Czyz syskin at ihug.com.au
Tue Oct 5 16:23:13 CEST 2004

Tom Jacobs wrote:

> I'm back to threading xvid after a week or so writing reports and have a few
> (probably basic) questions about the variables and bitstream.
> I'm kinda confused by mv16, mvs[] and pmvs[]. which one of these are the
> differential prediction that is written to the bitstream and thus the one i
> will need to recalculate? are all 4 values of the array written or just a
> specific one?

pmvs are the ones written to the bitstream. As for how many, that
depends on macroblock mode:
if mode==MODE_INTER4V, all four are written
if mode=MODE_INTER and mb->mcsel==0 (normal inter block), it's only
pmv[0] that is written
otherwise, (MODE_INTRA or mcsel==1), nothing is written.

That's for p-frames and s-frames.


More information about the XviD-devel mailing list