Patent ID: 8498876

Claim:
Method for reducing or eliminating intermodulation introduced by aliasing in a real-valued filterbank used for spectral envelope adjustment, comprising: analysing an input signal to obtain information; and using the obtained information to restrain envelope adjustment capabilities of the real-valued filterbank by grouping gain-values of adjacent channels of the real-valued filterbank, wherein the real-valued filterbank is configured for generating a plurality of subband signals generated by filtering a signal using an analysis filterbank, the real-valued filterbank having subband filters, adjacent subband filters of the filterbank having transition bands overlapping in an overlapping range, and wherein the analysing comprises examining a subband signal originating from a subband filter and an adjacent subband signal originating from an adjacent subband filter to determine, whether the subband signal and the adjacent subband signal have aliasing generating signal components in the overlapping range to obtain grouped subband signals in response to a specific result of the examination, the specific result of the examination indicating that the subband signal and the adjacent subband signal have aliasing generating signal components in the overlapping range.