Low-Complexity SNR Transcoding for H.264/AVC

J. De Cock, S. Notebaert, P. Lambert, K. De Wolf, and R. Van de Walle (Belgium)


Transcoding, Selective transmission, Rate reduction, H.264/AVC


Selective removal of residual coefficients is a fast method for SNR transcoding. In this paper, we extend the archi tecture for selective transmission that existed for MPEG-1 and MPEG-2 Video, and apply it to bitstreams coded using the state-of-the-art H.264/AVC video coding standard. We analyze the effect of coefficient dropping on CAVLC en tropy coding, by using a traditional frequency-based and a less prevalent level-based criterium for rate reduction. Test results show that in H.264/AVC the latter technique pro vides a better trade-off between rate reduction and visual quality of the transcoded bitstreams. As a special case, we introduce trailing one dropping, which reduces the bitrate up to 30%. Because of its improved rate reduction perfor mance for higher quantization parameters, these methods are highly suitable for rate control algorithms.

Important Links:

Go Back