摘要： MP3采用MPEG-1 LayerⅢ音频压缩编码标准，数据压缩率高、失真小，同时解码需要占用较大的内存空间。针对以上问题，在16 bit定点数字信号处理器芯片实现MP3解码算法时，对一些复杂算法进行优化，并且通过合理分配内部动态和静态存储空间，对动态存储器进行直接存储器存取操作，将动态数据临时存储在外存中，对静态存储器通过空间混用和压缩冗余数据等方法缩减内存占用空间。在解码速度提高的情况下，内存占用从大于40 KB降至15.9 KB。

关键词: MPEG-1 LayerⅢ解码, 数字信号处理器, 直接存储器存取

Abstract: MP3 uses MPEG-1 Layer Ⅲ audio codec standard, as its high compression ratio and low distortion, the on time decoding algorithm is complex and needs more internal memory. Aiming at the above problem, this paper optimizes some complex algorithms, when 16 bit fix point Digital Signal Processor(DSP) implements MP3 decoding algorithm. It appropriately allocates the static and dynamic memory, transfers the dynamic data to external memory by Direct Memory Access(DMA) for dynamic memory. By overlap memory and removing redundant data, the storage of static memoryoan be reduced. With the improvement of decoding rate, the storage of internal memory decreases to 15.9 KB from more than 40 KB.

Key words: MPEG-1 Layer Ⅲ decoding, Digital Signal Processor(DSP), Direct Memory Access(DMA)

中图分类号: 

• TP37