Efficient implementation of nearly perfect reconstruction FIR cosine-modulated filterbanks

In this paper, a new fast implementation of nearly perfect reconstruction finite impulse response (FIR) cosine-modulated filterbanks is shown. A new expression for the analysis bank has been developed, and based on it, an efficient implementation structure is obtained for specific prototype filter lengths. The new computationally efficient algorithm can be applied to both the conventional cosine-modulated filterbank and the Koilpillai-Vaidyanathan pseudo-quadrature mirror filterbank. We also show how the implementation cost (measured in multiplications and additions per input sample) is reduced.