Patent ID: 8144783

Claim:
A method for transcoding from an H.264 format to an MPEG-2 format, comprising the steps of: (A) decoding an input video stream in said H.264 format to generate a picture having a plurality of macroblocks with a plurality of H.264 motion vectors pointing to at least three of a plurality of H.264 reference frames; (B) scaling said H.264 motion vectors of said picture to generate a plurality of seed motion vectors of said picture that point to at most two of a plurality of MPEG-2 reference frames, (C) adjusting an MPEG-2 group of pictures to utilize a least number of lowest priority frames among said MPEG-2 reference frames; and (D) coding said macroblocks of said picture into an output video stream in said MPEG-2 format based on said seed motion vectors.