Cosine-modulated two-dimensional time-varying filter banks

Two-dimensional (2-D) filter banks are widely used for analysis and synthesis systems applied to subband coding of image. Recent years, time-varying filter banks that vary the structure of them appropriately for a local property of signals have been studied to apply to the compression of data of image. In time-varying filter banks, each different part of signals is processed with different filter coefficients or different number of channels (a different sampling matrix). Those signals have to be perfectly reconstructed even across transition of the filter banks. In this paper, we consider time-varying systems of cosine-modulated 2-D filter banks for arbitrary sampling lattices. We show perfect reconstruction (PR) conditions for such time-varying filter banks that vary filter coefficients or a sampling matrix. Some applications are presented to show the effectiveness of this method.