Perceptual Quality Assessment of HEVC and VVC Standards for 8K Video

The goal of no-reference image quality assessment (NR-IQA) is to evaluate their perceptual quality of digital images without using the distortion-free, pristine counterparts. NR-IQA is an important part of multimedia signal processing since digital images can undergo a wide variety of distortions during storage, compression, and transmission. In this paper, we propose a novel architecture that extracts deep features from the input image at multiple scales to improve the effectiveness of feature extraction for NR-IQA using convolutional neural networks. Specifically, the proposed method extracts deep activations for local patches at multiple scales and maps them onto perceptual quality scores with the help of trained Gaussian process regressors. Extensive experiments demonstrate that the introduced algorithm performs favorably against the state-of-the-art methods on three large benchmark datasets with authentic distortions (LIVE In the Wild, KonIQ-10k, and SPAQ).

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Perceptual quality assessment of 3D synthesized images

2017 IEEE International Conference on Multimedia and Expo (ICME) ◽

10.1109/icme.2017.8019307 ◽

2017 ◽

Cited By ~ 9

Author(s):

Muhammad Shahid Farid ◽

Maurizio Lucenteforte ◽

Marco Grangetto

Keyword(s):

Quality Assessment ◽

Perceptual Quality

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Perceptual Quality Assessment of Low-light Image Enhancement

ACM Transactions on Multimedia Computing Communications and Applications ◽

10.1145/3457905 ◽

2021 ◽

Vol 17 (4) ◽

pp. 1-24

Author(s):

Guangtao Zhai ◽

Wei Sun ◽

Xiongkuo Min ◽

Jiantao Zhou

Keyword(s):

Image Quality ◽

Quality Assessment ◽

Image Enhancement ◽

Dynamic Range ◽

State Of The Art ◽

Perceptual Quality ◽

Low Light ◽

Light Image ◽

Light Enhancement

Low-light image enhancement algorithms (LIEA) can light up images captured in dark or back-lighting conditions. However, LIEA may introduce various distortions such as structure damage, color shift, and noise into the enhanced images. Despite various LIEAs proposed in the literature, few efforts have been made to study the quality evaluation of low-light enhancement. In this article, we make one of the first attempts to investigate the quality assessment problem of low-light image enhancement. To facilitate the study of objective image quality assessment (IQA), we first build a large-scale low-light image enhancement quality (LIEQ) database. The LIEQ database includes 1,000 light-enhanced images, which are generated from 100 low-light images using 10 LIEAs. Rather than evaluating the quality of light-enhanced images directly, which is more difficult, we propose to use the multi-exposure fused (MEF) image and stack-based high dynamic range (HDR) image as a reference and evaluate the quality of low-light enhancement following a full-reference (FR) quality assessment routine. We observe that distortions introduced in low-light enhancement are significantly different from distortions considered in traditional image IQA databases that are well-studied, and the current state-of-the-art FR IQA models are also not suitable for evaluating their quality. Therefore, we propose a new FR low-light image enhancement quality assessment (LIEQA) index by evaluating the image quality from four aspects: luminance enhancement, color rendition, noise evaluation, and structure preserving, which have captured the most key aspects of low-light enhancement. Experimental results on the LIEQ database show that the proposed LIEQA index outperforms the state-of-the-art FR IQA models. LIEQA can act as an evaluator for various low-light enhancement algorithms and systems. To the best of our knowledge, this article is the first of its kind comprehensive low-light image enhancement quality assessment study.

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Perceptual Quality Assessment of Cartoon Images

IEEE Transactions on Multimedia ◽

10.1109/tmm.2021.3121875 ◽

2021 ◽

pp. 1-1

Author(s):

Hangwei Chen ◽

Xiongli Chai ◽

Feng Shao ◽

Xuejin Wang ◽

Qiuping Jiang ◽

...

Keyword(s):

Quality Assessment ◽

Perceptual Quality

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Visual Saliency and Perceptual Quality Assessment of 3D Meshes

Advances in Multimedia and Interactive Technologies - Intelligent Multidimensional Data and Image Processing ◽

10.4018/978-1-5225-5246-8.ch003 ◽

2018 ◽

pp. 38-115

Author(s):

Anass Nouri ◽

Christophe Charrier ◽

Olivier Lezoray

Keyword(s):

Quality Assessment ◽

State Of The Art ◽

Saliency Detection ◽

Visual Saliency ◽

Ground Truth ◽

The State ◽

Perceptual Quality ◽

Adaptive Smoothing ◽

Definition Of ◽

Mesh Database

This chapter concerns the visual saliency and the perceptual quality assessment of 3D meshes. Firstly, the chapter proposes a definition of visual saliency and describes the state-of-the-art methods for its detection on 3D mesh surfaces. A focus is made on a recent model of visual saliency detection for 3D colored and non-colored meshes whose results are compared with a ground-truth saliency as well as with the literature's methods. Since this model is able to estimate the visual saliency on 3D colored meshes, named colorimetric saliency, a description of the construction of a 3D colored mesh database that was used to assess its relevance is presented. The authors also describe three applications of the detailed model that respond to the problems of viewpoint selection, adaptive simplification and adaptive smoothing. Secondly, two perceptual quality assessment metrics for 3D non-colored meshes are described, analyzed, and compared with the state-of-the-art approaches.

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Interobserver variability in quality assessment of magnetic resonance images

BMC Medical Imaging ◽

10.1186/s12880-020-00505-z ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Rafal Obuchowicz ◽

Mariusz Oszust ◽

Adam Piorkowski

Keyword(s):

Magnetic Resonance ◽

Image Quality ◽

Quality Assessment ◽

Image Quality Assessment ◽

Interobserver Variability ◽

Poor Performance ◽

Magnetic Resonance Images ◽

Perceptual Quality ◽

Mr Images

Abstract Background The perceptual quality of magnetic resonance (MR) images influences diagnosis and may compromise the treatment. The purpose of this study was to evaluate how the image quality changes influence the interobserver variability of their assessment. Methods For the variability evaluation, a dataset containing distorted MRI images was prepared and then assessed by 31 experienced medical professionals (radiologists). Differences between observers were analyzed using the Fleiss’ kappa. However, since the kappa evaluates the agreement among radiologists taking into account aggregated decisions, a typically employed criterion of the image quality assessment (IQA) performance was used to provide a more thorough analysis. The IQA performance of radiologists was evaluated by comparing the Spearman correlation coefficients, ρ, between individual scores with the mean opinion scores (MOS) composed of the subjective opinions of the remaining professionals. Results The experiments show that there is a significant agreement among radiologists (κ=0.12; 95% confidence interval [CI]: 0.118, 0.121; P<0.001) on the quality of the assessed images. The resulted κ is strongly affected by the subjectivity of the assigned scores, separately presenting close scores. Therefore, the ρ was used to identify poor performance cases and to confirm the consistency of the majority of collected scores (ρmean = 0.5706). The results for interns (ρmean = 0.6868) supports the finding that the quality assessment of MR images can be successfully taught. Conclusions The agreement observed among radiologists from different imaging centers confirms the subjectivity of the perception of MR images. It was shown that the image content and severity of distortions affect the IQA. Furthermore, the study highlights the importance of the psychosomatic condition of the observers and their attitude.

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