【作者】 董志刚；

【导师】 张卫宁； 刘勇；

【作者基本信息】 山东大学 ， 电子与通信工程， 2008， 硕士

【摘要】 数字信号处理是伴随数值计算技术和计算机技术的发展而迅速发展起来的新兴学科,特别是数字信号处理器(DSP)的出现,使其理论得以广泛应用于实际系统之中。MPEG 1-LAYERS是MPEG-1国际标准音频(ISO/IEC 11172)第三层编码/解码算法,它具有压缩比例高,还原音质好等诸多优点。利用这种标准制作的MP3格式音乐,己经在网络上得到极大流行。但是目前市场上的MP3播放器大都是基于专用ASIC,因此存在着功能单一,灵活性不够的特点。基于以上背景,提出了基于定点DSP的MP3解码系统设计与实现的研究课题,本课题的主要目标就是以TI公司的定点DSP为核心,研究MP3硬件解码的快速算法及在定点DSP芯片上的实现。本论文详细叙述了论文作者设计研制的一种基于DSP的数字音频系统。该系统以TMS320C5402(DSP)为中央处理器,可完成MP3音频数字信号的分析和处理,并通过CODEC芯片实现对外界模拟音频信号的采集和发送。该系统配有大容量FLASH和硬盘,用于程序和音频数据的存储,128K字节高速RAM作为数据缓冲区。同时,通过USB控制芯片完成系统与PC机之间的数据通信。论文对ISO/IEC 11172标准中的LayerⅢ音频算法和基本原理进行了介绍。在对关键解压算法技术,如霍夫曼解码,反量化的快速算法进行深入研究的基础上,提出基于DSP汇编语言的快速算法实现方案验证,该系统可实现MPEG-1 LaverⅢ音频解码功能,并获得了良好的音乐质量。说明系统设计合理,算法实现正确。更多还原

【Abstract】 Digital signal processing is a new subject that improves quickly together with numerical computer technology and computer technology. Especially with appearance of Digital Signal Processor (DSP), its theory is applied widely to practical systems.MPEG-1 LAYERS describes the 3th Layers digital audio algorithms of the MPEG organization, and it has high compression and excellent audio ofquality.Themusic that compressed in this audio format has been very polular on the Internet .But most of the mp3 decoder is of defined-used ASIC,so there is lack of flexibility and upgrade.On the basis of above background, we advance that the designing and realizing of Fixed-point DSP Based MP3 Decode System. The goal of the thesis was to establish a hardware system which use a popular digital signal processor to decode the mp3 music.This paper describes on how to design a digital audio system based on TI’TMS 320C 54x DSP series. This system can accomplish analysis and processing of MP3 audio digital signals as well as sampling and transmitting external analog audio signals through CODEC. It also includes Flash and hard disk to store programs and data, 128K-Byte RAM as data buffer, usb controller to realize communication between system and PC.This paper gives a brief explanation of principle and algorithm of Layer III in international standard ISO/IEC11172. Especially give more detailed explanation about the key techniques, such as Huffman decoding and requantize, and bring forward the optimization schemes about them according to DSP assembly language.更多还原