Audio data compression manner and audio data compression circuit and audio data extension circuit

摘要

Digital audio data are divided into a plurality of frames, each of which includes a desired number of sub-band samples and which are gradually increased in a range between “ 16” and “ 1024” And are then compressed by way of psychoacoustics analysis and quantization and whereby compressed data are realized with a high compression ratio and small tone-generation latency. The compressed data are decoded by way of inverse quantization and sub-band synthesis and so that decoded data are sequentially written into a memory (e.g., a FIFO memory). Decoding is appropriately turned ON or OFF in response to a presently vacant capacity of the memory.