[XviD-devel] GMC committed

[Christoph Lampert]

Hi,

I just commited basic GME/GMC encoding support to dev-api-3 branch.
It's far from finished, but I thought maybe some of you wanted to have a
look. 

There is a new general flag XVID_GMC to switch it one. At the moment, 
the global motion (translational only) is calculated from glocal motion
vector (thanks to sysKin for the routine) and all MBs with this vector are
encoded as GMC instead of local motion. This is far from optimal of
course, and in fact it doesn't seem to save us any bits. In all my tests,
GMC files came out larger than non-GMC. 

GMC can be combined with everything else, i.e. inter4v and quarterpel.
GMC files can be decoded with ffmpeg or Divx5 (or reference) at the
moment (note that DivX5 doesn't support qpel+inter4v). I haven't
started on XVID GMC decoding maybe somebody else volunteers?

GMC+Bframes will most likely not work yet, because I didn't do any tests.
However, without GMC, behaviour should be identical to earlier versions,
including working Bframes. 

Have fun and test! And if you find any clip which gets smaller with GMC
than without, please tell me, too. 

gruel 

-- 
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