A fast adaptive image restoration filter for reducing block artifact in compressed images

Author

Choung, Yoo Chen ; Paik, Joon Ki

Author_Institution

Dept. of Electr. Eng, Chung-Ang Univ., Seoul, South Korea

Volume

43

Issue

4

fYear

1997

fDate

11/1/1997 12:00:00 AM

Firstpage

1340

Lastpage

1346

Abstract

We propose a fast adaptive image restoration filter using DCT-based block-classification for reducing block artifact in compressed images. More specifically, edge direction of each block is classified by using the DCT coefficients, and the adaptive constrained least squares (CLS) filter with corresponding direction is used for smoothing the discontinuity between blocks. For real-time application, the proposed restoration filter can be realized in the form of a truncated FIR filter, which is suitable for postprocessing reconstructed images in HDTV, DVD, or video conferencing systems

Keywords

FIR filters; adaptive filters; adaptive signal processing; discrete cosine transforms; edge detection; image classification; image coding; image restoration; least squares approximations; smoothing methods; transform coding; DCT coefficients; DCT-based block-classification; DVD; HDTV; adaptive constrained least squares filter; block artifact reduction; blocks discontinuity smoothing; edge direction; fast adaptive image restoration filter; image compression; real-time application; reconstructed images postprocessing; truncated FIR filter; video conferencing systems; Adaptive filters; Discrete cosine transforms; Finite impulse response filter; HDTV; Image coding; Image reconstruction; Image restoration; Least squares methods; Real time systems; Smoothing methods;

fLanguage

English

Journal_Title

Consumer Electronics, IEEE Transactions on

Publisher

ieee

ISSN

0098-3063

Type

jour

DOI

10.1109/30.642409

Filename

642409