use extradata for stuff which is in the keyframes now?
the MV median predictor is patented IIRC
implement per picture halfpel interpolation
-compare the 6 tap and 8 tap hpel filters (psnr/bitrate and subjective quality)
try different range coder state transition tables for different contexts
Not Important:
+compare the 6 tap and 8 tap hpel filters (psnr/bitrate and subjective quality)
spatial_scalability b vs u (!= 0 breaks syntax anyway so we can add a u later)