摘要
传统的模拟语音PCM采用等长折叠二进制编码,其数码率较高,传输和处理所需系统资源较大。文章从语音信号抽样值的概率分布情况出发,在PCM编码的非均匀量化基础上,对13折线A律压扩特性采用变长编码,使信源的熵冗余得以减小,实现了语音MOS值不变情况下的压缩编码,同时,又运用EDA技术对压缩电路进行了基于CPLD的硬件设计。
For the traditional analog voice PCM using equal-length binary code of folding￡-its band rate is higher than others and system resources of transmission and processing required is greater. Based on the non-uniform quantification of PCM and the probability distribution of voice sampling signals, The variable-length encoding is used in 13 line A Law characteristic of pressure and expansion to decrease the entropy redundancy of information source. In turn ,the compression coding of digital voice is obtained about MOS 4.0, and the circuit of compression is designed using the EDA technology based on CPLD.
出处
《自动化与仪器仪表》
2010年第2期121-122,共2页
Automation & Instrumentation
关键词
PCM调制
压扩特性
HUFFMAN编码
信源熵
VHDL
PCM modulation
Characteristic of pressure and expansion
Huffman codingin
Information source entropy
VHDL
