ITU-T G.723.1语音编码器中自适应码本搜索算法分析  

The Analysis of Adaptive Codebook Searching Algorithm in ITU-T G.723.1 Speech Encoder

作　　者：张浩[1] 官骏鸣[2] 孙恩昌[3] 

机构地区：[1]电信科学技术第四研究所,西安710061 [2]黄山学院计算机系,安徽黄山245021 [3]西安电子科技大学,西安710071

出　　处：《无线通信技术》2005年第3期28-30,共3页Wireless Communication Technology

摘　　要：本文先对ITU-T G.723.1语音编解码器结构、工作方式做了简单的描述,然后对其中的基音预测模块做了算法上的具体分析,对输入、输出给该模块的参数做了明确说明,指出搜索过程是按照目标矢量(原始语音经过一系列处理后)与自适应码本贡献(用过去的激励重建语音)差值的平方最小化准则进行的。The excitation consists of two components. The adaptive codebook contribution is taken from a segment of the past excitation. This supplies the pitch-like components by placing repetitions of past pitch pulses into the correct position in the excitation. The second excitation component is the fixed codebook contribution. The search procedure for the best excitation is done sequentially. First an adaptive codebook contribution （pitch contribution） is determined assuming the fixed codebook contribution is zero. Then, given the adaptive codebook contribution, the appropriate fixed codebook contribution is found.

关 键 词：线性预测 自适应码本 基音贡献 

分 类 号：TN912.3[电子电信—通信与信息系统]