Cited by 301Image and Video Quality AssessmentImage Retrieval and Classification TechniquesDigital Media Forensic Detection

Blind image quality assessment through anisotropy

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Gabarda, Salvador, Cristóbal, Gabriel·2007·Journal of the Optical Society of America A

Abstract

We describe an innovative methodology for determining the quality of digital images. The method is based on measuring the variance of the expected entropy of a given image upon a set of predefined directions. Entropy can be calculated on a local basis by using a spatial/spatial-frequency distribution as an approximation for a probability density function. The generalized Rényi entropy and the normalized pseudo-Wigner distribution (PWD) have been selected for this purpose. As a consequence, a pixel-by-pixel entropy value can be calculated, and therefore entropy histograms can be generated as well. The variance of the expected entropy is measured as a function of the directionality, and it has been taken as an anisotropy indicator. For this purpose, directional selectivity can be attained by using an oriented 1-D PWD implementation. Our main purpose is to show how such an anisotropy measure can be used as a metric to assess both the fidelity and quality of images. Experimental results show that an index such as this presents some desirable features that resemble those from an ideal image quality function, constituting a suitable quality index for natural images. Namely, in-focus, noise-free natural images have shown a maximum of this metric in comparison with other degraded, blurred, or noisy versions. This result provides a way of identifying in-focus, noise-free images from other degraded versions, allowing an automatic and nonreference classification of images according to their relative quality. It is also shown that the new measure is well correlated with classical reference metrics such as the peak signal-to-noise ratio.

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  • Training-based no reference QA techniques perform at least as well as mean squared error.

    “Training based NR QA techniques have resulted in algorithms that perform at least as well as mean squared error, which has the benefit of a reference image [9], [10].”
  • The blind image quality assessment index based on Renyi entropy anisotropy has not been thoroughly evaluated on a large and comprehensive dataset.

    “In [11], blind image quality assessment indices that measure the anisotropy in the distorted image through the Renyi entropy are introduced. However, performance of this index has not been thoroughly evaluated on a large and comprehensive dataset.”

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Research works printed but not linked: 6

  1. [7]7. H. R. Sheikh, A. C. Bovik, and L. K. Cormack, 'Noreference quality assessment using natural scene statistics: JPEG2000,' IEEE Trans. Image Process. 14 , 1918-1927 (2005).
  2. [10]10. W. J. Williams, M. L. Brown, and A. O. Hero, 'Uncertainity, information and time-frequency distributions,' Proc. SPIE 1566 , 144-156 (1991).
  3. [17]17. N. Wiener, Cybernetics (Wiley, 1948).
  4. [18]18. A. Rényi, 'Some fundamental questions of information theory,' in Selected Papers of Alfréd Rényi , Pál Turán, ed. (Akadémiai Kiadó, 1976), Vol. 3, pp. 526-552 [Originally in Magy. Tud. Akad. III Oszt. Kózl. 10 , 251-282 (1960)].
  5. [21]21. R. Eisberg and R. Resnick, Quantum Physics (Wiley, 1974).
  6. [25]25. K. H. Brenner, 'A discrete version of the Wigner distribution function,' in Proceedings of EURASIP, Signal Processing II: Theories and Applications (North Holland, 1983), pp. 307-309.

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Authors
Gabarda, S., & Cristóbal, G.
Affiliations
Consejo Superior de Investigaciones Científicas (ES)
Venue
Journal of the Optical Society of America A
Published
2007-09-26
Volume
24
Issue
12
Pages
B42
ISSN
  • 1084-7529 (ISSN-L)
  • 1520-8532
OpenAlex
W2119999314
Cited by
301
References
33
Citations by year
2026: 4 · 2025: 6 · 2024: 8 · 2023: 8 · 2022: 9 · 2021: 17 · 2020: 14 · 2019: 18 · 2018: 28 · 2017: 39 · 2016: 28 · 2015: 26 · 2014: 22 · 2013: 25 · 2012: 20
FWCI
7.00
Type
journal article
Language
en
Open access
Locations
  • Journal of the Optical Society of America A (publishedVersion)
  • PubMed (publishedVersion)
  • DIGITAL.CSIC (Spanish National Research Council (CSIC)) (submittedVersion, other-oa)
Topics
  • Physical Sciences › Computer Science › Computer Vision and Pattern Recognition › Image and Video Quality Assessment
  • Physical Sciences › Computer Science › Computer Vision and Pattern Recognition › Image Retrieval and Classification Techniques
  • Physical Sciences › Computer Science › Computer Vision and Pattern Recognition › Digital Media Forensic Detection
Keywords
no-reference image quality assessment, image quality index, anisotropy, Rényi entropy, pseudo-Wigner distribution, direction selectivity, image degradation, image classification

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