Abstract: This article first specifies the process of G.729A standard. Then, it optimizes the larger operational quantity modules of the source code, according to the characteristics of low power loss and high-performance 16-bit fixed-point digital signal processing chip TMS320DM642. Finally, the performance is tested and evaluated and the optimized programs have met with the expectation in data storage and operational complexity. The distortion of the decoded speech is rather small. Key Words: G.729A; speech coding; DSP

摘要： 本文首先阐述了G.729A音编解码标准的流程。根据低功耗、高性能的16位定点的数字信号处理芯片TMS320DM642的特点对源代码中运算量较大的模块进行了代码优化。最后，在DSP硬件平台上对实现后的编解码器的复杂度和编解码的性能进行了测试。从实验结果看，经改进优化后的程序在内存占用和运算复杂度方面都达到了预期目标，语音信号经编码器编码解码之后失真很小。