An Improved Rate-Quantization Model for CABAC-Based Entropy Coding in H.264/AVC

• Main Authors: Chi-Chun Chao, 趙祈鈞
• Other Authors: Cheng-Fu Chou
• Format: Others
• Language: en_US
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/36386863445947563918

碩士 === 國立臺灣大學 === 資訊工程學研究所 === 102 === Rate-distortion optimization (RDO) is an efficient technique to improve coding performance in H.264/AVC, but the process also incurs a considerable complexity increase of the encoder. To reduce the computational cost, a fast rate estimation method is needed to avoid heavy computations of entropy coding during mode decision process. In this work, we attempt to adopt the coding behaviors of customized residuals that are extracted from part of RDO, to further estimate the output bit-rate of RDO with different quantization parameters (QPs). After the features are extracted by our dedicated rate-quantization (R-Q) model, we then analyze the characteristics of the syntax elements of context-adaptive binary arithmetic coding (CABAC) to construct our rate estimation scheme. Experiments show that the proposed method is able to efficiently provide a more accurate estimation of the actual output bit-rate than existing works.