C声音压缩及应用实例设计.doc

周全华：声音压缩技术及应用实例 42 - 声音压缩及应用实例设计学 生：学 号：专 业：软件工程班 级指导教师： 二O 一0年五月 PAGE III声音压缩及应用实例设计摘 要在MPEG标准中根据不同的业务需要定义了3种不同的语音编码技术：先进音频编码AAC、码激励线性预测CELP和谐波矢量激励编码HVXC。对于12/24khz和8/16khz采样的语音信号，编码速率高于4kb/s的中高速率编码，MPEG标准分别采用AAC和CELP算法。对于8khz采用的语音信号，当编码速率低于4kb/s的甚低速率编码时，MPEG标准采用了谐波矢量激励编码算法HVXC来进行语音的参数编码。从严格意义上说，HVXC是综合音频数据统计特性的波形编码和音频声学参数的参数编码两种方法的混合编码。关键词：语音信号处理；语音压缩编码；谐波矢量激励编码Sound compression and Application designABSTRACTIn MPEG parametric speech coding,the harmonic vector excition coding(HVXC) algorithm is used for very low bit rate coding.Parameter analyzing and synthesizing proved algorithm is obtained based on HVXC.To the speech signal of Sampling with 12/24 kHz and 8/16 kHz,the encoding rate Highter than the middle-high rate encoding with 4 kb/s.In MPEG parametric speech coding Using the ACC and CELP lgorithm. To the speech signal of Sampling with 8 kHz,When the encoding rate low than lower rating of 4 kb/s,MPEG parametric using the harmonic vector excitation coding(HVCX) for speech of parameter encoding.From a strict sense ,HVCX is a mixed encoding with Comparehensive audio data statistical characteristics of the waveform coding and Audio acoustics parameter endoding.Keywords: speech signal processing; speech coding; harmonic vector exciation coding(HVXC)目录 TOC \o 1-3 \h \z \u HYPERLINK \l _Toc262954150 第一章 综述 PAGEREF _Toc262954150 \h - 1 - HYPERLINK \l _Toc262954151 1.1 课题的研究意义与现状 PAGEREF _Toc262954151 \h - 1 - HYPERLINK \l _Toc262954152 1.2 课题的研究目的及内容 PAGEREF _Toc262954152 \h 3 HYPERLINK \l _Toc262954153 第二章 宽带音频压缩的技术基础 PAGEREF _Toc262954153 \h 4 HYPERLINK \l _Toc262954154 2.1 人耳的掩蔽效应 PAGEREF _Toc262954154 \h 4 HYPERLINK \l _Toc262954155 2.2 子带编码 PAGEREF _Toc262954155 \h 5 HYPERLINK \l _Toc262954156 2.3 修正的离散余弦变换(MDCT) PAGEREF _Toc262954156 \h 6 HYPERLINK \l _Toc262954157 2.4 音响信号压缩的分析模型 PAGEREF _Toc262954157 \h 7 HYPERLINK \l _Toc262954158 2.5 动态码位分配 PAGEREF _Toc262954158 \h 8 HYPERLINK \l _Toc262954159 第三章 MPEG-1宽