Application of large macroblocks in H.264/AVC to wavelet-based scalable video transcoding

In this paper an efficient transcoder from H.264/AVC to a wavelet-based scalable video (W-SVC) codec is proposed. It exploits the advantage of using large sizes of prediction blocks in the W-SVC codec, and it is flexible in the sense that it is able to cope with any prediction structure in H.264/AVC stream, such as IPP or IBBP configuration with multiple reference frames. The reference frame mismatch between the source and target codecs is solved by a novel framework for motion vector approximation and refinement. The transcoder performance benefits from the use of block sizes larger than 16 × 16, especially for higher resolution content. Experimental results show a very good performance in terms of decoded video quality and system complexity.