Software Realization Of MPEG4-AAC Real-time Playing Based On AT76C120

AAC ( Advanced Audio Coding ) is a kind of audio coder using psychoacoustic mode which has the most high efficient and best quality. This thesis describes the theory of AAC encoder and decoder, and discusses the its specially encoder tools. According to the standard of AAC, the thesis realizes a real-time software AAC decoder based on ATMLE' s multimedia chip AT76C120, and combining with the MPEG decoder on chip, the thesis implements a MPEG-4 player with AAC audio format. AT76C120 is based on ARM7TDMI, and extends some peripheral hardware such as MPEG decoder and Audio data interface. In the process of realization, according to the characteristic of ARM7TDMI, the thesis does optimization on the key part of decoding, so that it can meet the requirements of system and memory.This thesis researches the method of realizing AAC real-time software decode on a single ARM processor without additional DSP. It is a creative action and will push the implementation of AAC to practice more quickly.