DSP-based Digital Audio Processing System Design And Implementation

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.