Method and system for multichannel perceptual audio coding using the cascaded discrete cosine transform or modified discrete cosine transform

摘要

A method and apparatus for coding audio signals having M sound channels in order to reduce the amount of audio data for transmission or storage. A comparison device is used to compare the coding efficiency in intra-channel signal redundancy reduction and the coding efficiency in inter-channel signal redundancy reduction in order to select a more efficient coding process. In particular, the modified discrete cosine transform (MDCT) process is used to compute the intra-channel coding efficiency and the cascade discrete cosine transform of the MDCT coefficients is used to compute the inter-channel coding efficiency. The efficiencies can be evaluated by computing a gain or the cross-channel correlation coefficients in the audio signals of the M sound channels.