Audio signal coding/decoding method

摘要

An adaptive transform coding/and decoding arrangement is provided to effectively exploit different redundancies between the bands of a spectrum envelope to effect coding at a low bit rate for an audio signal. In the adaptive transform coding method, the spectrum envelope is divided into bands so that different coding methods may be applied to the spectrum envelopes of the individual bands. By applying the present invention to the adaptive transform coding of an audio signal, the spectrum envelope can be adjusted to the coding/and transmission method which is suitable for the time fluctuation in each frequency band, so that the different redundancies for the individual bands can be effectively exploited to realize a highly efficient audio signal coding/and decoding method which has its bits reduced as required for coding the spectrum envelope.