Image coding using m-channel paraunitary filterbanks: Design with regularity and signal extension method

This paper proposes a signal extension method to realize image coding by M-channel paraunitary filter banks and a lattice configuration of the latter satisfying regularity. In the conversion code for finitely long signals such as images, nonextensional convolution is important for efficient coding without increasing the number of coded pixels. To this end, nonextensional convolution is realized in a general M-channel filter bank. Also, a signal extension method is proposed using singular value decomposition so that the extended signals are smooth. Next, in the M-channel paraunitary filter banks, a design method is proposed that is based on the lattice configuration satisfying the first-order regularity so that the DC leakage is prevented. Finally, the proposed method is applied to coding of various stationary images and the effectiveness of the method is demonstrated.