Transform one 4x4 coefficient quadrant in place without adding it to a
pixel destination. This is the transform portion of FFmpeg’s
ff_simple_idct44_add() used by WMV3 Simple/Main when RES_FASTTX=0.
Transform one 4x8 coefficient half in place without adding it to a pixel
destination. This is the transform portion of FFmpeg’s
ff_simple_idct48_add() used by WMV3 Simple/Main when RES_FASTTX=0.
Transform one 8x4 coefficient half in place without adding it to a pixel
destination. This is the transform portion of FFmpeg’s
ff_simple_idct84_add() and is used by WMV3 Simple/Main when RES_FASTTX=0.