Low complexity intra prediction algorithm for MPEG-2 to H.264/AVC transcoder

Transcoding MPEG-2 video into H.264/AVC format is highly necessary for the broad distribution of digital video contents to mobile terminals. Since H.264/AVC achieves great coding efficiency by employing computationally demanding algorithms, the computational complexity of the transcoder is one of technically challenging issues. The empirical results show that DCT energy trend in the decoded MB of MPEG-2 bitstream has strong correlation with the Intra prediction modes of H.264/AVC. Based on the relationship, the mode skipping rule of intra prediction mode decision in the H.264/AVC encoder part of the transcoder is proposed in this paper. The simulation results show that the proposed algorithm can achieve on average 72.36% reduction in computational complexity, compared with that of the conventional transcoder.