Enhanced transform domain intra prediction for MPEG-2 to H.264/AVC transcoding

In this paper, we proposed an enhanced transform-domain intra prediction method for H.264/AVC. In the proposed scheme, H.264/AVC intra prediction can be described by generalized linear operation after defining both H-filter and V-filter. Since intra prediction operation can be decomposed into some sparse matt-ices, we can reduce computational complexity for intra prediction. Our scheme can reduce the number of multiplication and addition operations more than Chen's by 22.4% and 21.6%, respectively, in each 4 x 4 block. Furthermore, we show that matrix multiplication can be simply processed using a look-up table which consists of 9 types of 4 x 4 constant matrices corresponding to 9 prediction modes in H.264. Consequently, we can insist that the proposed scheme in this paper can be used foe fast transform domain intra prediction in the area of transcoding MPEG-2 streams into H.264/AVC streams.