位平面算术编码的编码分离与MQ编码器改进

为了降低图像压缩中位平面算术编码的计算复杂度,提出了将算术编码从位平面扫描中分离,方便编码的并行计算。以JPEG2000的位平面编码为例,实现了位平面扫描和MQ编码的分离,然后根据编码分离后的算法特点,设计了一种改进的MQ编码器。对该算法在TMS320C6000系列DSP中的实现进行了研究,通过软件流水、循环展开、条件操作和优化选项等方法提高处理速度。编码独立和编码器改进相结合,使重建图像质量稍有提高,编码速度提高了8倍以上。

Isolation Coding of Bit Plane Scanning Arithmetic Coding and Modified MQ-coder

To lower the complexity of bit plane scanning arithmetic coding in image compression,arithmetic coding can be isolated from bit plane scanning for the purpose of parallel computing.The MQ-coding in JPEG2000 is isolated from the bit plane scanning.Based on the characteristic of coding algorithm after isolated coding,a modified MQ-coder is designed.Also,this paper studies the implementation in TMS320C6000 DSP of the modified algorithm.The processing speed is improved through software pipelining,loop unrolling,conditional instruction and complier options.The coding performance of arithmetic coding is superior and its speed is improved by eight times due to the implementation of isolation coding and modified MQ-coder.