1. Field of the Invention
The invention relates to a decoding apparatus, more particularly to a Context-based Adaptive Binary Arithmetic Coding (CABAC) decoding apparatus and a decoding method thereof.
2. Description of the Related Art
H.264/AVC is a recently developed video signal compression standard, which employs advanced encoding techniques to provide superior compression efficiency compared to other existing video signal compression standards such as MPEG-1, MPEG-2, H.263, etc.
H.264/AVC adopts Context-based Adaptive Variable Length Coding (CAVLC) technology or CABAC technology for entropy encoding to increase the coding efficiency. While the coding efficiency of CABAC technology is about 10% higher than that of CAVLC technology, encoding/decoding calculations in CABAC are more complex than those in CAVLC. During the CABAC decoding process, an input bit stream must at least go through an initialization step and an arithmetic decoding step before the decoding procedure can be completed. The total amount of time required by the initialization step and the arithmetic decoding step, which is actually relatively long, has a critical affect on the efficiency of a decoding system. As such, it is highly desired to reduce latency during the CABAC decoding process so as to improve the overall efficiency of the decoding system.