AUDIO CODING SYSTEM, AUDIO CODING METHOD, AUDIO CODER USING THE METHOD, RECORDING MEDIUM, AND MUSIC DISTRIBUTION SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide an audio coding system with which the high-quality audio coding can be realized with a small amount of calculation when the audio is coded by an MPEG 2 audio coding system AAC system etc. SOLUTION: The audio coding system is constituted so that a frequency band to be coded can be adaptively computed according to coding conditions, such as the frequency response characteristics and the bit rate of the incoming signal, and the sampling frequency, by initializing two or more scale factor bands and threshold information based on designation information of frame length and coding mode and computing the maximum scale factor band which specifies the frequency band to be coded among the scale factor bands based on a result of analyzing the frequency distribution of the incoming signal and the psyco-acoustic model.