A Fast Intra MB Mode Decision Method for the MPEG-2 to H.264 Transcoder

In this paper we propose an Intra mode decision method for the MPEG-2 to H.264/AVC transcoders to reduce the huge computational complexity. The DCT coefficients from the MPEG-2 decoder are used for the intra mode decision of H.264/AVC encoder. Based on the spatial activity analysis with the coefficients, early mode decision method between Intra16x16 and Intra4x4 modes and the Intra prediction direction are proposed. The empirical results show that the proposed method reduces about 70% computational complexity reduction compared with conventional method at the slight reduction in PSNR.