Title :
Artifact reduction in compressed images based on region homogeneity constraints using the projection onto convex sets algorithm
Author :
Weerasinghe, Chaminda ; Liew, Alan Wee-chung ; Yan, Hong
Author_Institution :
Sch. of Electr. & Inf. Eng., Sydney Univ., NSW, Australia
fDate :
10/1/2002 12:00:00 AM
Abstract :
A novel protection onto convex sets (POCS) method is presented for the suppression of blocking and ringing artifacts in a compressed image that contains homogeneous regions. A new family of convex smoothness constraint sets is introduced, using the uniformity property of image regions. This set of constraints allows different degrees of smoothing in different regions of the image, while preserving the image edges. The regions are segmented using the fuzzy c-means algorithm, which allows ambiguous pixels to be left unclassified. Experimental results on JPEG compressed images demonstrate that the proposed algorithm yields visually superior images compared to several of the previously reported POCS deblocking algorithms for the class of images considered.
Keywords :
data compression; feature extraction; fuzzy set theory; image coding; set theory; JPEG compressed images; POCS deblocking algorithms; POCS method; artifact reduction; blocking artifacts suppression; compressed images; convex smoothness constraint sets; fuzzy c-means algorithm; homogeneous regions; homogeneous regions extraction; image edge preservation; image region uniformity; image segmentation; pixels; projection onto convex sets algorithm; region homogeneity constraints; ringing artifacts suppression; Australia; Cutoff frequency; Discrete cosine transforms; Fuzzy sets; Image coding; Image segmentation; Information technology; Quantization; Smoothing methods; Transform coding;
Journal_Title :
Circuits and Systems for Video Technology, IEEE Transactions on
DOI :
10.1109/TCSVT.2002.804881