Subband-domain filtering of MPEG audio signals
Christopher A. Lanciani, Ronald W. Schafer · 1999
The cosine modulated filter bank is commonly used for the time-frequency decomposition of audio signals. For example, it is a basic element of the MPEG-1 and MPEG-2 audio coding standards. While this filter bank is not perfectly-reconstructing, it does provide for the cancelation of aliasing components that are introduced during the analysis decomposition. If the subband signals are to be processed, care must be taken to preserve the properties of the subband signals such that the aliased terms will be canceled successfully in the synthesis filter bank despite the modification of the subband signals. In this paper, a framework is provided for the generation and application of arbitrary FIR filters to signals that have been decomposed using the MPEG filter bank.