Title :
Variable-length lapped transforms with a combination of multiple synthesis filter banks for image coding
Author :
Tanaka, Toshihisa ; Hirasawa, Yasutaka ; Yamashita, Yukihiko
Author_Institution :
Dept. of Electr. & Electron. Eng., Tokyo Univ. of Agric. & Technol., Japan
Abstract :
A class of lapped transforms for image coding, which are characterized by variable-length synthesis filters, is introduced. In this class, the synthesis filter bank (FB) is first defined with an arbitrary combination of finite impulse response synthesis filters of perfect reconstruction FBs. An analysis FB is then obtained using direct matrix inversion or iterative implementation of Neumann series expansion. Moreover, to improve compression, we introduce a unitary transform that follows the analysis FB. This class enables a greater freedom of design than previously presented variable-length lapped transforms. We illustrate several design examples and present experimental results for image coding, which indicate that the proposed transforms are promising and comparable with conventional subband transforms including wavelets.
Keywords :
FIR filters; channel bank filters; data compression; image coding; transform coding; wavelet transforms; Neumann series expansion; compression; direct matrix inversion; finite impulse response synthesis filters; image coding; multiple synthesis filter banks; subband transforms; unitary transform; variable-length lapped transforms; variable-length synthesis filters; wavelets; Agricultural engineering; Channel bank filters; Filter bank; Finite impulse response filter; Helium; Image coding; Image reconstruction; Lattices; Transform coding; Wavelet transforms; Filter banks; image coding; lapped transforms; perfect reconstruction; Algorithms; Image Enhancement; Image Interpretation, Computer-Assisted; Information Storage and Retrieval; Numerical Analysis, Computer-Assisted; Sensitivity and Specificity; Signal Processing, Computer-Assisted;
Journal_Title :
Image Processing, IEEE Transactions on
DOI :
10.1109/TIP.2005.860341