Application And Realization Of MPEG-1/Audio Lay3 Decoder

With the development of Internet technology, IPTV(TV over Internet Protocol) appears. It will become one of the main service of telecommunication in the future. The paper mainly researches the Audio system of IPTV. In the Audio system, the encoding/decoding algorithm of Audio chooses the MPEG-1/Audio Lay3(MP3). The algorithm has the advantage of high compressing ratio, excellent audio quality and moderate algorithm complexity . So it is widely used in the digital audio store and the multimedia data transmission over Internet ,etc.So , the project is put forward to design the MP3 decoder and apply the decoder to the Audio system of IPTV. The goal of the thesis is to research the fast algorithm of MP3 decoder and realize it on the digital signal processor (DSP) of the ADI's Blackfin533 which can be applied to decode the real time data stream of MP3 in the Audio system of IPTV. In the thesis, Chapter One introduces the development of the digital Audio technology and the main work of the paper. Chapter Two in detail researches the encoding/decoding theory of MP3 and analyzes the MP3 algorithm. Chapter Three states the software and hardware development environment of the MP3 decoder and the applied skill of its function models. Chapter Four is the content of design and realization. Firstly in the chapter the real time MP3's decoder is realized on the Blackfin533 chip. Since the decoding algorithm of MP3 is a very complicated system with a high requirement in both the computing ability and the memory, in order to realize the MP3 decoder on the Blackfin533 chip, we have to do some algorithm and code optimization on some core modules. We apply a fast algorithm to the IMDCT of the IMDCT and subband synthesis module, as reduces the consumption of memory and computing. Then the test result of the real time MP3 decoder is presented. It indicates that the performance of the decoder confirms to the requirements of the Audio system. At the end , the MP3 decoder is applied to the Audio system of IPTV. the effect of the decoder's application in the Audio system of IPTV indicates that the decoder can decode the real time data stream of MP3.