Adaptive optimal decompositions with hybrid DCT-subband coding

A generalization of the discrete wavelet transform, i.e., the hybrid subband coding decomposition is introduced. It consists of the application of adequate invertible operators at each level of decomposition (inner-and inter-subbands) before application of the next level of decomposition. An important application is hybrid discrete cosine-transform (DCT)-subband coding, which produces optimal local (in time or frequency) decorrelation of the coefficients of decomposition