Multiscale decomposition and fusion‐based color contrast restoration for various water‐colored environments

2021 ◽  
Author(s):  
Sivamani Kalyana Sundara Rajan ◽  
Nedumaran Damodaran
Keyword(s):  
Color Contrast ◽  
Multiscale Decomposition

Expressions of color contrast as equivalent achromatic contrast

1982 ◽  
Author(s):  
David L. Post ◽  
Edward B. Costanza ◽  
Thomas M. Lippert
Keyword(s):  
Color Contrast ◽  
Achromatic Contrast

EFFECT OF COLOR CONTRAST ON VISUAL LOBE SHAPE CHARACTERISTICS1,2

2013 ◽  
pp. 130628095601001
Author(s):  
Steve N. H. Tsang ◽  
Alan H. S. Chan ◽  
R. F. Yu
Keyword(s):  
Color Contrast

scholarly journals Infrared and visible image fusion via octave Gaussian pyramid framework

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lei Yan ◽  
Qun Hao ◽  
Jie Cao ◽  
Rizvi Saad ◽  
Kun Li ◽  
...  
Keyword(s):  
Image Fusion ◽  
Low Frequency ◽  
Objective Evaluation ◽  
Visible Image ◽  
Composite Image ◽  
Multiscale Decomposition ◽  
Gaussian Pyramid ◽  
Fusion Methods ◽  
Scale Spaces ◽  
Fusion Framework

AbstractImage fusion integrates information from multiple images (of the same scene) to generate a (more informative) composite image suitable for human and computer vision perception. The method based on multiscale decomposition is one of the commonly fusion methods. In this study, a new fusion framework based on the octave Gaussian pyramid principle is proposed. In comparison with conventional multiscale decomposition, the proposed octave Gaussian pyramid framework retrieves more information by decomposing an image into two scale spaces (octave and interval spaces). Different from traditional multiscale decomposition with one set of detail and base layers, the proposed method decomposes an image into multiple sets of detail and base layers, and it efficiently retains high- and low-frequency information from the original image. The qualitative and quantitative comparison with five existing methods (on publicly available image databases) demonstrate that the proposed method has better visual effects and scores the highest in objective evaluation.

scholarly journals Underwater Image Enhancement Based on Multi-Scale Fusion and Global Stretching of Dual-Model

Mathematics ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 595
Author(s):  
Huajun Song ◽  
Rui Wang
Keyword(s):  
Image Enhancement ◽  
Poor Performance ◽  
Weight Coefficient ◽  
Color Contrast ◽  
Dual Model ◽  
Spatial Cues ◽  
Multi Scale ◽  
Imaging Model ◽  
Underwater Image ◽  
Enhancement Method

Aimed at the two problems of color deviation and poor visibility of the underwater image, this paper proposes an underwater image enhancement method based on the multi-scale fusion and global stretching of dual-model (MFGS), which does not rely on the underwater optical imaging model. The proposed method consists of three stages: Compared with other color correction algorithms, white-balancing can effectively eliminate the undesirable color deviation caused by medium attenuation, so it is selected to correct the color deviation in the first stage. Then, aimed at the problem of the poor performance of the saliency weight map in the traditional fusion processing, this paper proposed an updated strategy of saliency weight coefficient combining contrast and spatial cues to achieve high-quality fusion. Finally, by analyzing the characteristics of the results of the above steps, it is found that the brightness and clarity need to be further improved. The global stretching of the full channel in the red, green, blue (RGB) model is applied to enhance the color contrast, and the selective stretching of the L channel in the Commission International Eclairage-Lab (CIE-Lab) model is implemented to achieve a better de-hazing effect. Quantitative and qualitative assessments on the underwater image enhancement benchmark dataset (UIEBD) show that the enhanced images of the proposed approach achieve significant and sufficient improvements in color and visibility.

Comparing ten WCAG tools for accessibility evaluation of websites

2021 ◽  
pp. 1-23
Author(s):  
Shashank Kumar ◽  
Jeevitha Shree DV ◽  
Pradipta Biswas
Keyword(s):  
User Interaction ◽  
Web Accessibility ◽  
User Profile ◽  
Syntactic Analysis ◽  
Color Contrast ◽  
Careful Evaluation ◽  
Accessibility Issues ◽  
Web Developers ◽  
Compare And Contrast ◽  
Common User

BACKGROUND: Web accessibility is one of the most important aspects of building a website. It is important for web developers to ensure that their website is accessible according to WCAG standards for people with different range of abilities. There is plethora of tools for ensuring conformance to WCAG standards but not many studies compared performance of automatic WCAG tools. OBJECTIVE: This paper compares a set of ten WCAG tools and their results in terms of ease of comprehension and interpretation by web developers. We proposed a Common User Profile format to help personalize contents of website making it accessible to people with different range of abilities. METHODS: We selected ten WCAG tools from World Wide Web Consortium (W3C) to evaluate landing pages of two popular websites. For each webpage, we identified accessibility issues and recommended alternate suggestions to help developers improve accessibility. Further, we highlighted accessibility issues that cannot be captured only through conformance to WCAG tools; and proposed additional methods to evaluate accessibility through an Inclusive User Model. We then demonstrated how simulation of user interaction can capture usability and accessibility issues that are not detected through only syntactic analysis of websites’ content. Finally, we proposed a Common User Profile format that can be used to compare and contrast accessibility systems and services, and to simulate and personalize interaction for users with different range of abilities. RESULTS AND CONCLUSIONS: After careful evaluation of two websites using the ten tools, we noted that, both websites lacked color contrast between background and foreground; lack of sign language alternatives; opening of pop-ups without proper warnings and so on. Further, results from comparative analysis of selected web accessibility tools noted that, there is no single tool that can be found ideal in all aspects. However, from our study, Utilitia Validator by Utilitia SP. z O.O was considered the most feasible tool. By rectifying and incorporating issues and alternate suggestions by simulation study and Common User Profile format respectively, developers can improve both websites making it accessible to maximum audience.

scholarly journals Classification of non stationary signals using multiscale decomposition

2010 ◽  
Vol 03 (02) ◽  
pp. 193-199 ◽  
Author(s):  
Marwa Chendeb ◽  
Mohamad Khalil ◽  
David Hewson ◽  
Jacques Duchên
Keyword(s):  
Multiscale Decomposition ◽  
Stationary Signals

Explanation for Neon Color Effect in Achromatic Line Segments on Chromatic Inducers Based on the Multiple Interpretation Hypothesis

2005 ◽  
Vol 101 (1) ◽  
pp. 267-282
Author(s):  
Seiyu Sohmiya
Keyword(s):  
Visual System ◽  
Line Segment ◽  
Color Contrast ◽  
Achromatic Color ◽  
Line Segments ◽  
Color Effect ◽  
Complementary Color ◽  
Multiple Interpretation ◽  
Color Induction ◽  
Simultaneous Color Contrast

In van Tuijl's neon configurations, an achromatic line segment on a blue inducer produces yellowish illusory color in the illusory area. This illusion has been explained based on the idea of the complementary color induced by the blue inducer. However, it is proposed here that this illusion can be also explained by introducing the assumption that the visual system unconsciously interprets an achromatic color as information that is constituted by transparent and nontransparent colors. If this explanation is correct, not only this illusion, but also the simultaneous color contrast illusion can be explained without using the idea of the complementary color induction.

Color stimuli perception in presence of light scattering

2006 ◽  
Vol 23 (3-4) ◽  
pp. 597-601 ◽  
Author(s):  
MARIS OZOLINSH ◽  
MICHÉLE COLOMB ◽  
GATIS IKAUNIEKS ◽  
VARIS KARITANS
Keyword(s):  
Visual Acuity ◽  
Light Scattering ◽  
Luminance Contrast ◽  
White Background ◽  
Color Contrast ◽  
Entire Area ◽  
Red Color ◽  
Blue Component ◽  
Different Color ◽  
Landolt C

Perception of different color contrast stimuli was studied in the presence of light scattering: in a fog chamber in Clermont-Ferrand and in laboratory conditions where light scattering of similar levels was obtained, using different light scattering eye occluders. Blue (shortest wavelength) light is scattered in fog to the greatest extent, causing deterioration of vision quality especially for the monochromatic blue stimuli. However, for the color stimuli presented on a white background, visual acuity in fog for blue Landolt-C optotypes was higher than for red and green optotypes on the white background. The luminance of color Landolt-C optotypes presented on a LCD screen was chosen corresponding to the blue, green, and red color contributions in achromatic white stimuli (computer digital R, G, or B values for chromatic stimuli equal to RGB values in the achromatic white background) that results in the greatest luminance contrast for the white–blue stimuli, thus advancing the visual acuity for the white-blue stimuli. Besides such blue stimuli on the white background are displayed with a uniform, spatially unmodulated distribution of the screen blue phosphor emission over the entire area of the screen including the stimulus C optotype area. It follows that scattering, which has the greatest effect on the blue component of screen luminance, has the least effect on the perception of white–blue stimuli.

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