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Alan C. Bovik

Bio: Alan C. Bovik is an academic researcher from University of Texas at Austin. The author has contributed to research in topics: Image quality & Video quality. The author has an hindex of 102, co-authored 837 publications receiving 96088 citations. Previous affiliations of Alan C. Bovik include University of Illinois at Urbana–Champaign & University of Sydney.


Papers
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Journal ArticleDOI
TL;DR: The LIVE Color+3D Database as mentioned in this paper contains 12 sets of color images with corresponding ground truth range maps in a high-definition resolution of 1280×720, and the analysis results show that the distributions of range gradients conditioned on the Gabor responses have very similar exponential shapes for both luminance and chrominance channels.
Abstract: Color and depth play important roles in natural scenes and in vision, and their perception is related. Extensive work has been conducted on studying the luminance statistics of natural scenes; however, there is very little work done on analyzing the statistics between luminance and range in natural scenes, not to mention color and range. In this paper, we present the LIVE Color+3D Database, which contains 12 sets of color images with corresponding ground truth range maps in a high-definition resolution of 1280×720. We examined the statistical distribution of range gradients conditioned on the Gabor responses of the color images, as well as the variations of statistical measures of range gradients with changes in the Gabor responses. The analysis results show that the distributions of range gradients conditioned on the Gabor responses have very similar exponential shapes for both luminance and chrominance channels. Moreover, we also found that the depth difference between neighboring pixels increases as the corresponding magnitudes of the Gabor responses rise.

4 citations

Journal ArticleDOI
TL;DR: A quantitative accuracy evaluation wherein the proposed method outperforms a microcanonical annealing approach by Barnard and a cooperative approach by Zitnick and Kanade, while using fewer match quality evaluations than either.
Abstract: We present an efficient method that computes dense stereo correspondences by stochastically sampling match quality values. Nonexhaustive sampling facilitates the use of quality metrics that take unique values at noninteger disparities. Depth estimates are iteratively refined with a stochastic cooperative search by perturbing the estimates, sampling match quality, and reweighting and aggregating the perturbations. The approach gains significant efficiencies when applied to video, where initial estimates are seeded using information from the previous pair in a novel application of the Z-buffering algorithm. This significantly reduces the number of search iterations required. We present a quantitative accuracy evaluation wherein the proposed method outperforms a microcanonical annealing approach by Barnard and a cooperative approach by Zitnick and Kanade , while using fewer match quality evaluations than either. The approach is shown to have more attractive memory usage and scaling than alternatives based on exhaustive sampling.

3 citations

Journal ArticleDOI
TL;DR: In this article , a new gaming-specific No-Reference Video Quality Assessment (NR VQA) model called the Gaming Video Quality Evaluator (GAMIVAL) was proposed, which combines and leverages the advantages of spatial and temporal gaming distorted scene statistics models, a neural noise model, and deep semantic features.
Abstract: The mobile cloud gaming industry has been rapidly growing over the last decade. When streaming gaming videos are transmitted to customers' client devices from cloud servers, algorithms that can monitor distorted video quality without having any reference video available are desirable tools. However, creating No-Reference Video Quality Assessment (NR VQA) models that can accurately predict the quality of streaming gaming videos rendered by computer graphics engines is a challenging problem, since gaming content generally differs statistically from naturalistic videos, often lacks detail, and contains many smooth regions. Until recently, the problem has been further complicated by the lack of adequate subjective quality databases of mobile gaming content. We have created a new gaming-specific NR VQA model called the Gaming Video Quality Evaluator (GAMIVAL), which combines and leverages the advantages of spatial and temporal gaming distorted scene statistics models, a neural noise model, and deep semantic features. Using a support vector regression (SVR) as a regressor, GAMIVAL achieves superior performance on the new LIVE-Meta Mobile Cloud Gaming (LIVE-Meta MCG) video quality database.

3 citations

Proceedings ArticleDOI
12 Feb 2014
TL;DR: A novel visual discomfort prediction algorithm dubbed 3D-AVM Predictor is presented to quantify the visual discomfort by including neural responses to sensory stimuli of both accommodation and vergence, and the 3D local bandwidth is defined based on physiological optics of binocular vision and foveation for optical activity of accommodation from the perspective of the VA cross-link.
Abstract: For clear binocular vision in the brain, the neural interaction for accommodation and vergence is performed via inter-operation of two cross-links: accommodative-vergence (AV) and vergence-accommodation (VA). However, when people watch stereo images on stereoscopic display, the neural operation is interrupted due to alternations of the cross-link gains, which are attributed as the main reason of visual discomfort on stereo images in terms of Accommodation-Vergence Mismatch (AVM). In this paper, we present a novel visual discomfort prediction algorithm dubbed 3D-AVM Predictor to quantify the visual discomfort by including neural responses to sensory stimuli of both accommodation and vergence. In particular, we define the 3D local bandwidth (BW) based on physiological optics of binocular vision and foveation for optical activity of accommodation from the perspective of the VA cross-link. Since the 3D-AVM Predictor encompasses the anomalous motor responses of both accommodation and vergence, it is demonstrated that the performance is statistically superior to those of conventional works which rely on the factor of disparity distribution only.

3 citations

Proceedings ArticleDOI
23 Mar 1992
TL;DR: Measuring local frequencies is an effective approach to analyzing globally nonstationary, yet locally coherent images by imposing stabilizing terms developing naturally from assumptions on the signal, leading to an iterative constraint propagation algorithm.
Abstract: Measuring local frequencies is an effective approach to analyzing globally nonstationary, yet locally coherent images. The local frequencies may be manifested as, e.g., flowlike, granular, or oriented patterns. It is necessary to make spectral measurements accurate in both frequency and space, conflicting requirements constrained by a generalized uncertainty relationship. Such spectral measurements can be obtained from multiple wavelet-like channel filters that yield a locus of possible frequency solutions. Thus locus of solutions is maximally localized in both space/frequency if the channel filters are Gabor wavelets. A solution is obtained by imposing stabilizing terms developing naturally from assumptions on the signal. The frequency measurement problem is cast as a regularized extremum problem, leading to an iterative constraint propagation algorithm. As a to an iterative constraint propagation algorithm. As a byproduct local image contrast measurement is also obtained. >

3 citations


Cited by
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Journal ArticleDOI
TL;DR: In this article, a structural similarity index is proposed for image quality assessment based on the degradation of structural information, which can be applied to both subjective ratings and objective methods on a database of images compressed with JPEG and JPEG2000.
Abstract: Objective methods for assessing perceptual image quality traditionally attempted to quantify the visibility of errors (differences) between a distorted image and a reference image using a variety of known properties of the human visual system. Under the assumption that human visual perception is highly adapted for extracting structural information from a scene, we introduce an alternative complementary framework for quality assessment based on the degradation of structural information. As a specific example of this concept, we develop a structural similarity index and demonstrate its promise through a set of intuitive examples, as well as comparison to both subjective ratings and state-of-the-art objective methods on a database of images compressed with JPEG and JPEG2000. A MATLAB implementation of the proposed algorithm is available online at http://www.cns.nyu.edu//spl sim/lcv/ssim/.

40,609 citations

Book
01 Jan 1998
TL;DR: An introduction to a Transient World and an Approximation Tour of Wavelet Packet and Local Cosine Bases.
Abstract: Introduction to a Transient World. Fourier Kingdom. Discrete Revolution. Time Meets Frequency. Frames. Wavelet Zoom. Wavelet Bases. Wavelet Packet and Local Cosine Bases. An Approximation Tour. Estimations are Approximations. Transform Coding. Appendix A: Mathematical Complements. Appendix B: Software Toolboxes.

17,693 citations

Proceedings ArticleDOI
21 Jul 2017
TL;DR: Conditional adversarial networks are investigated as a general-purpose solution to image-to-image translation problems and it is demonstrated that this approach is effective at synthesizing photos from label maps, reconstructing objects from edge maps, and colorizing images, among other tasks.
Abstract: We investigate conditional adversarial networks as a general-purpose solution to image-to-image translation problems. These networks not only learn the mapping from input image to output image, but also learn a loss function to train this mapping. This makes it possible to apply the same generic approach to problems that traditionally would require very different loss formulations. We demonstrate that this approach is effective at synthesizing photos from label maps, reconstructing objects from edge maps, and colorizing images, among other tasks. Moreover, since the release of the pix2pix software associated with this paper, hundreds of twitter users have posted their own artistic experiments using our system. As a community, we no longer hand-engineer our mapping functions, and this work suggests we can achieve reasonable results without handengineering our loss functions either.

11,958 citations

Posted Content
TL;DR: Conditional Adversarial Network (CA) as discussed by the authors is a general-purpose solution to image-to-image translation problems, which can be used to synthesize photos from label maps, reconstructing objects from edge maps, and colorizing images, among other tasks.
Abstract: We investigate conditional adversarial networks as a general-purpose solution to image-to-image translation problems. These networks not only learn the mapping from input image to output image, but also learn a loss function to train this mapping. This makes it possible to apply the same generic approach to problems that traditionally would require very different loss formulations. We demonstrate that this approach is effective at synthesizing photos from label maps, reconstructing objects from edge maps, and colorizing images, among other tasks. Indeed, since the release of the pix2pix software associated with this paper, a large number of internet users (many of them artists) have posted their own experiments with our system, further demonstrating its wide applicability and ease of adoption without the need for parameter tweaking. As a community, we no longer hand-engineer our mapping functions, and this work suggests we can achieve reasonable results without hand-engineering our loss functions either.

11,127 citations

Journal ArticleDOI
01 Apr 1988-Nature
TL;DR: In this paper, a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) is presented.
Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

9,929 citations