Cited by 337Image and Video Quality AssessmentImage Retrieval and Classification TechniquesDigital Media Forensic Detection

The DOI matches its Crossref record; 38 of the 38 references it cites were found in a registry or an index; none of the 16 sources its claims cite is checked for support yet.

RRED Indices: Reduced Reference Entropic Differencing for Image Quality Assessment

Soundararajan, R., Bovik, A. C.·2012·IEEE Transactions on Image Processing

Abstract

We study the problem of automatic "reduced-reference" image quality assessment (QA) algorithms from the point of view of image information change. Such changes are measured between the reference- and natural-image approximations of the distorted image. Algorithms that measure differences between the entropies of wavelet coefficients of reference and distorted images, as perceived by humans, are designed. The algorithms differ in the data on which the entropy difference is calculated and on the amount of information from the reference that is required for quality computation, ranging from almost full information to almost no information from the reference. A special case of these is algorithms that require just a single number from the reference for QA. The algorithms are shown to correlate very well with subjective quality scores, as demonstrated on the Laboratory for Image and Video Engineering Image Quality Assessment Database and the Tampere Image Database. Performance degradation, as the amount of information is reduced, is also studied.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

The paper introduces RRED indices, reduced-reference image quality assessment algorithms that measure average absolute differences between scaled wavelet-domain entropies of a reference image and a Gaussian-scale-mixture natural-image approximation of the distorted image. Across LIVE and TID2008, the indices correlate well with subjective scores and degrade gracefully as reference information is reduced, with some variants approaching full-reference performance.

Key findings

  • On LIVE, RRED M16/16 achieved overall SROCC 0.9429 and LCC 0.9385 using L/36 scalars, compared with PSNR SROCC 0.8754 and VIF (FR) SROCC 0.9636; RRED M10/10 achieved overall SROCC 0.9343 using L/144 scalars.
  • Filtering and subsampling reduced reference information but degraded overall SROCC from 0.9429 at L/36 to 0.8543 at L/9296.
  • Single-number algorithms had overall SROCC 0.7682 for σ²W = 0, 0.7978 for σ²W = 0.1, and 0.8877 for σ²W = 1; RRED* using 4 numbers achieved overall SROCC 0.8606, outperforming WNISM (0.7651) but below Curvelet (0.9104) and HWD2 (0.9418).
  • On TID2008, RRED M16/16 achieved overall SROCC 0.824, above VIF (0.750), VSNR (0.705), PSNR (0.553), and WNISM (0.512), but below MSSIM (0.853); RRED 1/22 achieved 0.521.

Methods

  • The RRED family computes the average absolute difference between scaled entropies of wavelet coefficients after an additive Gaussian neural noise channel, modeling both reference and distorted wavelet coefficients as Gaussian scale mixtures; algorithms vary by subband and by the amount of reference information via filtering/subsampling.
  • Experiments used LIVE (779 distorted images, five distortion categories) and TID2008 (17 distortion types, 1700 distorted images), with a steerable pyramid decomposition using 6 orientations at 4 scales (25 subbands), 3×3 blocks (N = 9), and σ²W = 0.1 except in the single-number noise study; parameters were estimated by maximum likelihood without database training.
  • Performance was assessed with Spearman rank-order correlation (SROCC) and linear correlation coefficient (LCC) after logistic nonlinearity against subjective DMOS/MOS, compared with PSNR, VIF, MSSIM, VSNR, WNISM, Curvelet, and HWD2.

Limitations

  • The paper states that overall performance of single-number algorithms may be improved by better aligning scores across distortion categories, that multiscale decomposition increases complexity and needs efficient implementations, and that dependence on viewing distance requires better understanding; future work includes video.
  • The paper reports that performance degrades with subsampling and that single-number algorithms are sensitive to neural noise variance; Gaussian blur performance decreases as σ²W increases (0.9698 at 0, 0.9038 at 0.1, 0.6108 at 1).
  • Evident from reported tables, though not framed as limitations by the authors: RRED* overall SROCC 0.8606 is lower than Curvelet 0.9104 and HWD2 0.9418 on LIVE, and TID2008 RRED M16/16 is below MSSIM overall (0.824 vs 0.853) with low SROCC for mean shift (0.538) and contrast change (0.542).

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Integrity signals

Registry

Crossref · 10.1109/tip.2011.2166082

Cites

38 of 38 references verified0 citation errors · 0 not checkable

Statistics

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Verification

Claims the paper makes

28 Own interpretation · 20 No basis given · 17 Own result · 11 Not checked yet · 3 Own method · 2 Sources not found

Verify all 13 references — free account

Show all 42 claims

  • It may state two separate claims as one. 20
  • Probably not a substantial claim. 24
39 of 39
  • The authors state this as an assumption.

    Modifications of natural image statistics are perceptually noticeable.

    “It is also based on the assumption that such modifications of natural image statistics are perceptually noticeable.”
  • The authors state this as an assumption.

    Non-overlapping blocks of wavelet coefficients are independent and identically distributed.

    “Non-overlapping blocks are assumed independent and identically distributed (i.i.d.).”
  • The authors state this as an assumption.

    The wavelet coefficients of the distorted image can be modeled as a Gaussian scale mixture distribution.

    “This means that we model the wavelet coefficients of the distorted image as well as a Gaussian scale mixture distribution.”
  • The authors state this as an assumption.

    The perceived reference and distorted images pass through an additive neural noise channel, where the noise is a zero mean Gaussian random vector for each block of coefficients.

    “We additionally model the perceived reference and distorted images as passing through an additive neural noise channel, where the noise is assumed to be a zero mean Gaussian random vector for each block of coefficients.”
  • The authors state this as an assumption.

    The covariance matrices K_U_k and K_V_k are full rank.

    “In the following, assume that K U k and K V k are full rank matrices.”
  • The authors state this as an assumption.

    The scalar premultiplier S_mk and the Gaussian vector U_mk are independent.

    “Also, S mk and ¯ U mk are independent.”
  • The authors state this as an assumption.

    The neural noise vectors W_mk and W'_mk are independent of each other, independent of C_mk and D_mk, and independent across indices m and k.

    “where W mk ∼ N (0 , σ 2 W I N ) and W ′ mk ∼ N (0 , σ 2 W I N ) , W mk and W ′ mk are independent of each other, independent of ¯ C mk and ¯ D mk and independent across the indices m and k .”
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Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

2 of 2

Citations

Cites

Research works printed but not linked: 1

  1. 0, JNDmetrix Technology

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Metadata

Authors
Soundararajan, R., & Bovik, A. C.
Affiliations
The University of Texas at Austin (US)
Venue
IEEE Transactions on Image Processing
Published
2012-02
Volume
21
Issue
2
Pages
517-526
ISSN
  • 1057-7149 (ISSN-L)
  • 1941-0042
OpenAlex
W2037243393
Cited by
337
References
38
Citations by year
2026: 5 · 2025: 17 · 2024: 9 · 2023: 14 · 2022: 22 · 2021: 23 · 2020: 21 · 2019: 22 · 2018: 41 · 2017: 36 · 2016: 36 · 2015: 27 · 2014: 33 · 2013: 21 · 2012: 9
FWCI
21.69
Type
journal article
Language
en
Open access
closed
Locations
  • IEEE Transactions on Image Processing (publishedVersion)
  • PubMed (publishedVersion)
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
reduced-reference image quality assessment, entropy difference, wavelet coefficients, image distortion, visual perception, subjective quality correlation

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