Motion Compensation

Copy8x8QP_MPEG4, Copy16x8QP_MPEG4, Copy16x16QP_MPEG4
Copy fixed size blocks with quarter-pixel accuracy.
OBMC8x8HP_MPEG4, OBMC16x16HP_MPEG4, OBMC8x8QP_MPEG4
Perform overlapped block motion compensation (OBMC) for one luminance block.