一种新的AVS指数哥伦布码算法

AVS Exponential-Golomb Code Algorithm

指数哥伦布码是AVS视频压缩标准中熵编码的重要组成部分。在研究指数哥伦布码的特点及其编解码算法的基础上,利用哥伦布码码字的二进制大小与编码码值的数学关系,提出一种新的指数哥伦布编解码算法。尤其是在指数哥伦布解码方面,摒弃变长码只能逐位读取、逐位判断计算的思路,采用32 bit读取并用设定公式计算的方法。实验结果表明,该算法比AVS参考代码中的指数哥伦布编、解码方法所用时间分别缩短约10%和30%。

The exponential-Golomb code is a important part of entropy encoding in AVS video compression standard. This paper investigates the characteristics, encoding and decoding algorithm of exponential-Golomb code, and presents a new algorithm for Exponential-Golomb encoding and decoding according to the mathematic relation between binary value of exponential-Golomb code. Especially in exponential-Golomb decoding, the algorithm discards the idea of reading and judgement bit-by-bit, uses the method of 32 bit reading and given formula. Experimental result shows that the exponential-Golomb code algorithm shortens the encoding time by about 10% than the algorithm applied in AVS reference software, and shortens the decoding time by about 30% than the algorithm applied in AVS reference software.