Patent ID: 8249883
Filing Date: 2012-08-21
Classification: G10L

Abstract:
1. A method of reconstructing multi-channel audio from a compressed bitstream, the method comprising: receiving the compressed bitstream, the compressed bitstream containing a plurality of coded channels and power correlation parameters, the number of coded channels being fewer than a number of physical channels of the multi-channel audio, the power correlation parameters characterizing a full power correlation matrix; decoding a vector of coded audio channel coefficients and power correlation parameters from the received bitstream for a frequency band; forming a virtual audio channel coefficients vector for the frequency band comprising the decoded vector of coded audio channel coefficients and coefficients of decorrelated versions of the coded audio channels; determining the full power correlation matrix for the frequency band from the power correlation parameters; constructing a linear transform for multi-channel audio reconstruction relating the virtual audio channel coefficients vector to a reconstructed multi-channel audio coefficients vector; applying the linear transform to the virtual audio channel coefficients vector to produce the reconstructed multi-channel audio coefficients vector; and with a processing unit, applying an inverse time-frequency transform to the reconstructed multi-channel audio coefficients vector to reproduce the multi-channel audio.