Patent ID: 8295493

Claim:
Method to generate multiple output audio channels (y 1 , . . . , yM) from multiple input audio channels (x 1 , . . . , xL), in which the number of output channels is equal or higher than the number of input channels, this method comprising the steps of: by means of linear combinations of input subbands X 1 (i), . . . , XL(i), computing one or more independent sound subbands representing signal components, by removing from an input subband signal components which are also present in one or more of the other input subbands, the independent sound subbands representing signal components which are independent between the input subbands, by means of linear combinations of the input subbands X 1 (i), . . . , XL(i), computing one or more localized direct sound subbands representing signal components which are contained in more than one of the input subbands, and computing corresponding direction factors representing the ratios of the localized direct sound subbands representing signal components contained in two or more input subbands, generating the output subbands, Y 1 (i) . . . YM(i), comprising the steps of: for each independent sound subband, selecting a subset of the output subbands, and scaling the corresponding independent sound subband, for each direction factor, selecting the subset of output subbands, and scaling the corresponding localized direct sound subband, and adding the scaled corresponding independent sound subband to the scaled corresponding localized direct sound subband, and converting the output subbands, Y 1 (i) . . . YM(i), to time domain audio signals, y 1 . . . yM.