【作者】 杨艳；

【导师】 刘教瑜；

【作者基本信息】 武汉理工大学 ， 控制理论与控制工程， 2006， 硕士

【摘要】 近年来,随着多媒体信息技术和网络技术的高速发展,数字语音压缩技术的应用领域越来越广泛,尤其在可视电话、IP网络电话、数字蜂窝移动通信、综合业务数字网、公共交换电话网和话音存储转发系统等领域中,目的是在保证语音一定质量的前提下尽可能降低其编码比特率,便于在有限的传输带宽内让出更多的信道来传送图像、文档、计算机文件和其他数据流。为此,国际电信联盟(ITU)于1996年分别推出了G.729标准,即共轭结构代数码激励线性预测编码(CS-ACELP)方案,以及G.723.1标准,即具有6.3kbps和5.3kbps两个编码速率的低码率编码算法,两者具有语音质量高、低延时和稳定性好的优点,可用于数字语音通信领域,具有很高的研究价值。 本文首先简要的介绍了语音压缩编码算法的发展进程,以及发展趋势。在着重分析和研究了G.729标准与G.723.1标准的算法原理的基础上,详细说明了基于高性能DSP(TMS320VC5509)的语音压缩编解码系统的实现方法,并针对算法的实时实现出现的运算量大的问题,提出了算法实现的代码优化方法。通过将优化后的算法加载到TMS320VC5509中,进行仿真,分析两种算法的压缩性能。 全文共分为五章,第一章概述语音压缩编码算法的分类、标准、发展趋势等;第二章详细分析G.729标准与G.723.1标准的算法原理;第三章、第四章介绍了基于TMS320VC5509的语音编解码系统的硬件、软件设计;最后一章对全文的工作总结。更多还原

【Abstract】 With the rapid development of Multimedia communication technology and Internet technology, Application of Digital speech Coding is more widely in recent years, especially in the area of Visible telephone, IP Internet telephone、 Digital cellular mobile communication、 Integrated server digital network、 Public Switched Telephone Network and packet transfer Voice System, etc. Digital speech Coding can reduce rate of bits, for the purpose of provided more channels to transfer image, document、 computer files and other Data stream, but the operation must assure quality of speech. So ITU introduce G729, a voice compressing criterion, Conjugate-Structure Algebraic- Code-Excited Linear -Prediction (CS-ACELP) and G723.1 criterion, 6.3kbps 和 5.3kbps rate speech Coding in 1996. Two criterions have the advantages of high speech quality, low time delay and good stability, which can be applied in the area of digital speech communication and be worth researching highly.First of all, the development course and tendency of Speech Compress Coding has been introduced. On the basis of analysis and research to theory of G.729 criterion, G.723.1 criterion arithmetic, realization of the algorithm of speech coding’s system based on TMS320VC5509 is narrated. Due to large operation when arithmetic is run in real-time, several methods of optimized codes was put forward. Loaded optimized codes in TMS320VC5509 and simulated, two arithmetic’s performance was compared.Whole paper is made up of five chapters. In the first chapter, summarizes the classification、 standard and tendency of Speech Coding;in the second chapter, theories of G729 criterion, G723.1 criterion arithmetic are analyzed;design of hardware and software speech coding’s system based on TMS320VC5509 is given in the third and forth chapter;in the last chapter, the main conclusions of the design are summarized.更多还原