COMPLEX-TRANSFORM CHANNEL CODING WITH EXTENDED-BAND FREQUENCY CODING Russian patent published in 2011 - IPC H03M7/30 

FIELD: information technology.

SUBSTANCE: in the method of encoding multi-channel audio data, multi-channel audio data comprising a group of plural source channels is received and channel extension coding is performed on said multi-channel audio data: forming a combined channel from said group of plural source channels, encoding the combined channel and determining plural parameters for representing individual source channels of the group as modified versions of the encoded combined channel which contains a parameter representing an imaginary-to-real ratio of cross-correlation between the individual source channels. Multi-channel audio data then undergo frequency extension coding: partitioning frequency bands in the multi-channel audio data into a baseband group and an extended band group, and coding audio coefficients in the extended band group based on audio coefficients in the baseband group.

EFFECT: high efficiency of processing digital sound while maintaining quality of the sound.

20 cl, 42 dwg