改进的分布式算术码及其在生物认证中的应用

Improved distributed arithmetic coding and its application in biometric authentication

为解决解码过程中存在误删正确解码路径概率较高、解码速度较慢的问题,提出一种基于深度优先搜索的分布式算术码(distributed arithmetic coding,DAC)解码算法。综合考虑码流内在特性、码流外在特性及解码路径长度等因素对解码路径权重的影响,得到新的路径权重计算公式;用部分搜索代替全局搜索,减少算法的搜索量。将该算法用于生物信息安全认证系统,仿真结果表明,该算法比传统基于宽度优先搜索的算法具有明显的优越性。

To solve the problems of the higher probability of mis-pruning the correct decoding paths and the slower decoding speed during the decoding process,an improved decoding algorithm of distributed arithmetic coding（DAC）based on depth-first search was proposed.The effects of the intrinsic,extrinsic feature of the bitstream and the length of decoding paths on path metric were comprehensively considered,and the new computing expression of the path metric was obtained.The search volume was reduced using partial search instead of global search.The proposed algorithm was applied to biometric authentication system.The simulation results indicate that the developed algorithm is superior to the traditional decoding algorithm based on breadth-first search.