Coding Mode Decision for High Quality MPEG-2 to H.264 Transcoding

This paper proposes a high quality coding mode decision method for MPEG-2 to H.264 transcoding. Here, we evaluate the coding modes of MPEG-2 stream in order to specify whether they should be inherited or changed in H.264 coding since many new coding schemes such as intra prediction have been introduced in H.264. By adaptively determining suitable intra/inter modes according to DCT coefficients, motion vectors (MVs), and neighboring macroblock (MB) modes of input MPEG-2 stream, high quality transcoding has been realized. In the experiment, we observed that the proposed method can improve a peak signal to noise ratio (PSNR) up to 0.29 dB at the cost of 22% more processing time compared with the conventional transcoding method.