Efficient inter/intra mode decision for H.264/AVC inter frame transcoding

In this paper, we propose an efficient inter/intra mode decision for H.264/AVC inter frame transcoding. A zero-block decision scheme is first employed to select some candidate inter and intra modes for prediction. Soon afterward, we incorporate a fast multi-reference frame motion estimation with adaptive search window into inter mode decision. For intra mode decision we suggest a mode refinement scheme to eliminate improbable modes for RDO calculations to a greater extent. The experimental results reveal that average 93% of computation time can be saved for the proposed H.264 inter frame transcoding algorithm, when compared with fully decoding/encoding procedure. The degradation in the rate-distortion performance is fairly small.