DSP audio compression system based on G.723.1

This paper introduces an audio compression system based on G.723.1 algorithm. The system is able to work in full duplex pattern as it can compress and decompress the received data at the same time. The system works on TI´s TMS320C5509A which is a fixed-point digital signal processor. The DSP chip uses MCBSP (Multi-Channel Buffered Serial Port) to receive and transfer data between codec chip AIC23 and DMA (Direct Memory Access). G.723.1 algorithm is transplanted to DSP chip and optimized in order to meet the requirement of the system. Four methods are introduced in this paper to optimize the algorithm. After optimization, the time of compression and decompression is reduced from more than 310ms to 11ms. This system use RS232 to communicate with other upper monitor.