Proceedings ArticleDOI
Wavelet-based post-processing of low bit rate transform coded images
Ramesh A. Gopinath,M. Lang,Haitao Guo,J.E. Odegard +3 more
- Vol. 2, pp 913-917
TLDR
This work proposes a novel method based on wavelet thresholding for enhancement of decompressed transform coded images that works remarkably well in "deblocking" of DCT compressed images.Abstract:
We propose a novel method based on wavelet thresholding for enhancement of decompressed transform coded images. Transform coding at low bit rates typically introduces artifacts associated with the basis functions of the transform. In particular, the method works remarkably well in "deblocking" of DCT compressed images. The method is nonlinear, computationally efficient, and spatially adaptive and has the distinct feature that it removes artifacts yet retain sharp features in the images. An important implication of this result is that images coded using the JPEG standard can efficiently be postprocessed to give significantly improved visual quality in the images. The algorithm can use a conventional JPEG encoder and decoder for which VLSI chips are available. >read more
Citations
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Journal ArticleDOI
A deblocking algorithm for JPEG compressed images using overcomplete wavelet representations
TL;DR: This paper introduces a new approach to deblocking of JPEG compressed images using overcomplete wavelet representations using cross-scale correlations among wavelet coefficients, which is capable of achieving the same peak signal-to-noise ratio (PSNR) improvement as the best iterative method and giving visually very pleasing images as well.
Journal ArticleDOI
Review of Postprocessing Techniques for Compression Artifact Removal
Mei-Yin Shen,C.-C. Jay Kuo +1 more
TL;DR: A review and analysis of recent developments in postprocessing techniques, including various types of compression artifacts, two types of postprocessing algorithms based on image enhancement and restoration principles and current bottlenecks are addressed.
Journal ArticleDOI
Blocking artifacts suppression in block-coded images using overcomplete wavelet representation
Alan Wee-Chung Liew,Hong Yan +1 more
TL;DR: A noniterative, wavelet-based deblocking algorithm that can suppress both block discontinuities and ringing artifacts effectively while preserving true edges and textural information is proposed.
Patent
Image data post-processing method for reducing quantization effect, apparatus therefor
Yung-Lyul Lee,Hyun Wook Park +1 more
TL;DR: In this article, an image data post-processing method for reducing quantization effect induced when image data compressed based on a block is decoded, and an apparatus therefor is presented.
Journal ArticleDOI
Enhancement of JPEG-Compressed Images by Re-application of JPEG
TL;DR: This approach simply re-applies JPEG to the shifted versions of the already-compressed image, and forms an average, which offers better performance than other known methods, including those based on nonlinear filtering, POCS, and redundant wavelets.
References
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