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Analysis of dct spectrum statistics for image processing applications

Research output: Contribution to journalArticleScientificpeer-review


Original languageEnglish
Pages (from-to)1051-1070
Number of pages20
JournalTelecommunications and Radio Engineering
Issue number12
Publication statusPublished - 2015
Publication typeA1 Journal article-refereed


Statistical characteristics of coefficients of discrete cosine transform (DCT) in 8x8 pixel blocks of grayscale images are analyzed. Robust estimators of distribution scale and tail heaviness are used in analysis since it is shown that the considered distributions are essentially non-Gaussian and they are better described by generalized Gaussian distribution (GGD) with variable parameters. Parameters of these distributions are determined for noise-free images and the same images corrupted by additive white Gaussian noise. It is demonstrated that the noise presence considerably changes distribution that approaches to Gaussian for high frequency DCT coefficients. Parameters of GGD model depend on both image properties and noise variance. The usefulness of the obtained results for two operations of image processing (variance estimation and filtering) is shown.

ASJC Scopus subject areas


  • DCT spectrum statistics, Generalized Gaussian distribution, Image processing, Robust parameter estimation

Publication forum classification

Field of science, Statistics Finland