AMR-WB固定码本快速搜索新方法  

Novel fast fixed codebook search method for AMR-WB.

作　　者：唐骏[1,2] 袁江南[1,2] 

机构地区：[1]厦门理工学院电子与电气工程系,福建厦门361024 [2]厦门大学信息科学与技术学院,福建厦门361004

出　　处：《计算机工程与应用》2012年第36期14-18,共5页Computer Engineering and Applications

基　　金：福建省教育厅科技计划(No.JB10148);厦门市科技计划(No.3502Z20103038)

摘　　要：在AMR-WB中,固定码本搜索是影响性能和复杂度的关键模块,约占总复杂度的40%。为了降低计算量,提出了一种码字分裂、子码字脉冲取代的高效码本搜索算法。该算法包括四步:一个初始码字分裂为两个或更多的子码字;每个子码字通过最不重要脉冲取代法进行更新;更新后的子码字合成一个候选的码字;比较初始码字和候选码字,选择优者作为最后的码字。实验表明,与传统方法相比,编码时间减小约16%。In AMR-WB, the fixed codebook search is the crucial part in both performance and complexity, and it takes up about 40% of total complexity. To reduce the computational load, this paper proposes an efficient codebook search algorithm based on sub-codeword pulse replacement. The proposed algorithm consists of four steps. Firstly, an initial codeword is divided into two or more sub-codewords. Secondly, each sub-codeword is updated using the least important pulse replacement method. Thirdly, the updated sub-codewords are combined as a candidate code- word. Finally, by comparing the candidate codeword and the initial codeword, better one is selected as the final codeword. Experimental results show that the proposed algorithm reduces the overall complexity by about 16% with minor degradation in speech quality, when compared to the traditional algorithms.

关 键 词：语音编码 固定码本搜索 码字分裂 宽带自适应多码率 

分 类 号：TN912.3[电子电信—通信与信息系统]