An Enhanced Robust Entropy Coder for Video Codecs Based on Context-Adaptive Reversible VLC

This paper proposes an enhanced RVLC coder, context-adaptive reversible variable length coder (CRVLC), for DCT coefficients by using the techniques of data sub-partitioning and context modeling. The data sub-partitioning means that the data part of DCT coefficients is split into several small sub-partitions. As each sub-partition can be reversibly decoded by RVLC, more data as well as higher error resilience can be obtained. The context modeling exploits the correlation of DCT coefficients for further compression. This modeling defines the contexts by hierarchical-dependent information. The information is also available in the backward decoding, so that it supports the reversible decoding. And with it the data outputted by CRVLC can be naturally placed into multiple sub-partitions.