Small and moderate color differences. IV. Color-difference-perceptibility ellipses in surface-color space

1983 ◽  
Vol 8 (1) ◽  
pp. 31-39 ◽  
Author(s):  
Danny C. Rich ◽  
Fred W. Billmeyer
Keyword(s):  
Color Space ◽  
Color Difference ◽  
Surface Color ◽  
Color Differences

Subjective Sensation of Color Differences – Determination of Thresholds Depending on Color Tones and Resolution

2015 ◽  
Vol 21 (1) ◽  
pp. 21-27 ◽  
Author(s):  
Christian Brischke ◽  
Tanja Borcharding ◽  
Uta Mengel
Keyword(s):  
Color Space ◽  
Color Difference ◽  
Threshold Values ◽  
Color Tone ◽  
Color Changes ◽  
Art Objects ◽  
Color Differences ◽  
Subjective Sensation ◽  
Total Color Difference

Abstract Colors are frequently defined by three points on the L*a*b* coordinates of the CIELAB color space, and the distance between two colors can be expressed as the total color difference ΔE. In particular with respect to reproducibility of print media color differences are an important parameter, as well as for car finishes and textile dyes. Color changes are also the result of ageing and weathering which is an issue for art objects and in the building and restoration sector. However, the subjective perceptibility of color differences depends on numerous factors and general thresholds are difficult to define. This study aimed therefore on defining tolerance levels for color changes in dependence of color tones and color tone combinations as well as their resolution. In total 30 test persons evaluated samples, which had been painted with acrylic artist colors with defined color differences (ΔE = 0–7). The test subjects realized color differences already at ΔE = 1–4 for the highest resolution. Threshold values have been identified for different tones as well as the effect of interdependencies between tones and the level of color heterogeneity between adjacent areas.

scholarly journals The Efficacy of Linked Color Imaging in the Endoscopic Diagnosis of Barrett’s Esophagus and Esophageal Adenocarcinoma

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Mamoru Tokunaga ◽  
Tomoaki Matsumura ◽  
Kentaro Ishikawa ◽  
Tatsuya Kaneko ◽  
Hirotaka Oura ◽  
...  
Keyword(s):  
Barrett’S Esophagus ◽  
Esophageal Adenocarcinoma ◽  
Barrett's Esophagus ◽  
Color Space ◽  
Color Difference ◽  
Blue Laser ◽  
Color Imaging ◽  
Color Differences ◽  
Blue Laser Imaging ◽  
Linked Color Imaging

Background. The present study aimed to evaluate the efficacy of linked color imaging (LCI) in diagnosing Barrett’s esophagus (BE) and esophageal adenocarcinoma (EAC). Methods. A total of 112 and 12 consecutive patients with BE and EAC were analyzed. The visibility scores of BE and EAC ranging from 4 (excellent visibility) to 0 (not detectable) were evaluated by three trainees and three experts using white light imaging (WLI), LCI mode, and blue laser imaging bright (BLI-b) mode. In addition, L ∗ a ∗ b ∗ color values and color differences ( Δ E ∗ ) were evaluated using the CIELAB color space system. Results. The visibility score of the BE in LCI mode ( 2.94 ± 1.32 ) was significantly higher than those in WLI ( 2.46 ± 1.48 ) and BLI-b mode ( 2.35 ± 1.46 ) ( p < 0.01 ). The color difference ( Δ E ∗ ) from the adjacent gastric mucosa in LCI mode ( 17.11 ± 8.53 ) was significantly higher than those in other modes ( 12.52 ± 9.37 in WLI and 11.96 ± 6.59 in BLI-b mode, p < 0.01 ). The visibility scores of EAC in LCI mode ( 2.56 ± 1.47 ) and BLI-b mode ( 2.51 ± 1.28 ) were significantly higher than that in WLI ( 1.64 ± 1.46 ) ( p < 0.01 ). The color difference ( Δ E ∗ ) from the adjacent normal Barrett’s mucosa in LCI mode ( 19.96 ± 7.97 ) was significantly higher than that in WLI ( 12.95 ± 11.86 ) ( p = 0.03 ). Conclusion. The present findings suggest that LCI increases the visibility of BE and EAC and contributes to the improvement of the detection of these lesions.

scholarly journals Objective Endoscopic Analysis with Linked Color Imaging regarding Gastric Mucosal Atrophy: A Pilot Study

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Kazuhiro Mizukami ◽  
Ryo Ogawa ◽  
Kazuhisa Okamoto ◽  
Mitsutaka Shuto ◽  
Kensuke Fukuda ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Color Space ◽  
Color Difference ◽  
Infection Status ◽  
Color Imaging ◽  
Mucosal Atrophy ◽  
Color Differences ◽  
Euclidean Distances ◽  
Linked Color Imaging ◽  
White Light Imaging

Objectives. We aimed to determine whether linked color imaging (LCI), a new image-enhanced endoscopy that enhances subtle differences in mucosal colors, can distinguish the border of endoscopic mucosal atrophy. Methods. This study included 30 patients with atrophic gastritis. In endoscopy, we continuously took images in the same composition with both LCI and white light imaging (WLI). In each image, the color values of atrophic and nonatrophic mucosae were quantified using the International Commission on Illumination 1976 (L∗, a∗, b∗) color space. Color differences at the atrophic border, defined as Euclidean distances of color values between the atrophic and nonatrophic mucosae, were compared between WLI and LCI for the overall cohort and separately for patients with Helicobacter pylori infection status. Results. We found that the color difference became significantly higher with LCI than with WLI in the overall samples of 90 points in 30 patients. LCI was 14.79 ± 6.68, and WLI was 11.06 ± 5.44 (P<0.00001). LCI was also more effective in both of the Helicobacter pylori-infected group (P=0.00003) and the Helicobacter pylori-eradicated group (P=0.00002). Conclusions. LCI allows clear endoscopic visualization of the atrophic border under various conditions of gastritis, regardless of Helicobacter pylori infection status.

Recent Advances in Color and Whiteness Evaluations in Dentistry

2019 ◽  
Vol 1 (1) ◽  
pp. 23-29 ◽  
Author(s):  
María M. Pérez ◽  
Oscar E. Pecho ◽  
Razvan Ghinea ◽  
Rosa Pulgar ◽  
Alvaro Della Bona
Keyword(s):  
Clinical Performance ◽  
Dental Materials ◽  
Color Space ◽  
Color Difference ◽  
Color Measurement ◽  
Tooth Color ◽  
Dental Research ◽  
Color Science ◽  
Difference Formula ◽  
Color Differences

Background: The final goal of color measurement or shade specification in dentistry is the reproduction by prosthetic materials of all important appearance characteristics of natural oral structures. The application of color science in dentistry is an objective way to measure and evaluate such structures and dental materials in clinical practice and dental research. Methods: Literature on color science was reviewed to present new metrics to evaluate color differences of dental materials and dental structures. Visual acceptability and perceptibility values of color differences are reviewed and new whiteness indexes to describe whiteness in dentistry are presented. Results: In the last decade, the CIELAB 50:50% perceptibility and acceptability thresholds were set to 1.2 and 2.7, respectively, and the CIEDE2000 50:50% perceptibility and acceptability thresholds were set to 0.8 and 1.8. The CIEDE2000 color-difference formula became increasingly popular in dentistry. Developments in color science have led to the description of tooth whiteness and changes in tooth whiteness based on whiteness indexes, with the most relevant being the WID whiteness index, which is a customized index based in CIELAB color space. Conclusion: The application of color science in dentistry has allowed the precise description of tooth color and whiteness. The revised and new CIEDE2000 color-difference formula is expected to fully replace the outdated CIELAB formula in almost all dental applications. Recent psychophysical studies have reported values of visual thresholds and new whiteness indexes, which can serve as quality control tools to guide the selection of esthetic dental materials, evaluate clinical performance, and interpret visual and instrumental findings in clinical dentistry, dental research, and subsequent standardization.

scholarly journals A Study of Automatic Judgment of Food Color and Cooking Conditions with Artificial Intelligence Technology

Processes ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 1128
Author(s):  
Chern-Sheng Lin ◽  
Yu-Ching Pan ◽  
Yu-Xin Kuo ◽  
Ching-Kun Chen ◽  
Chuen-Lin Tien
Keyword(s):  
Artificial Intelligence ◽  
Image Processing ◽  
Color Space ◽  
Color Difference ◽  
Color Space Conversion ◽  
Before And After ◽  
Artificial Intelligence Technology ◽  
Artificial Intelligence Algorithm ◽  
Time Image ◽  
Cooking Conditions

In this study, the machine vision and artificial intelligence algorithms were used to rapidly check the degree of cooking of foods and avoid the over-cooking of foods. Using a smart induction cooker for heating, the image processing program automatically recognizes the color of the food before and after cooking. The new cooking parameters were used to identify the cooking conditions of the food when it is undercooked, cooked, and overcooked. In the research, the camera was used in combination with the software for development, and the real-time image processing technology was used to obtain the information of the color of the food, and through calculation parameters, the cooking status of the food was monitored. In the second year, using the color space conversion, a novel algorithm, and artificial intelligence, the foreground segmentation was used to separate the vegetables from the background, and the cooking ripeness, cooking unevenness, oil glossiness, and sauce absorption were calculated. The image color difference and the distribution were used to judge the cooking conditions of the food, so that the cooking system can identify whether or not to adopt partial tumbling, or to end a cooking operation. A novel artificial intelligence algorithm is used in the relative field, and the error rate can be reduced to 3%. This work will significantly help researchers working in the advanced cooking devices.

Method to Create Perceptually Uniform Color Gradients with Optimized Color Differences between each Step for Data Visualization

2020 ◽  
Vol 64 (1) ◽  
pp. 1634-1638
Author(s):  
Derek Millard ◽  
Bradley M. Davis ◽  
Samineh C. Gillmore
Keyword(s):  
Data Visualization ◽  
Color Space ◽  
Original Method ◽  
Visual Environment ◽  
Color Differences ◽  
Color Gradient ◽  
Color Gradients ◽  
Specific Implementation

This paper presents an original method to create optimized color differences between each step of a CIELAB perceptually uniform color gradient. The relevant equations for the necessary color space transformations are discussed, along with the procedure to determine and optimize the color differences between each gradient step. A specific implementation for perceptually uniform color gradients is discussed for safe terrain clearance in manned aviation during a degraded visual environment.

Evaluation of change in color of denim fabric after various industrial washing processes with different fiber composition

2014 ◽  
Vol 11 (2) ◽  
pp. 107-110
Author(s):  
Mushtaq Mangat ◽  
A. Abbasi ◽  
Jakub Wiener
Keyword(s):  
Color Space ◽  
Color Difference ◽  
Fiber Composition ◽  
Obvious Change ◽  
Washing Machines ◽  
Difference Formula ◽  
Denim Fabric ◽  
Cielab Color

Traditional denim made by using 100% cotton and novel denim made by using cotton in warp and spun PP in the weft were treated in 11 different ways on industrial garment washing machines with the help of various textile auxiliaries and pumice. There is an obvious change in color of denim. This change was measured by using Spectrophotometer. Reflectance was taken as a variable to observe the intensity of change. Color difference was measured by using the CIELab color difference formula 1976. Color space coordinates (L*, a*, b*) and color difference ΔE were calculated between the untreated denim and treated denim.

scholarly journals Influence of UV Radiation on the Color Change of the Surface of Steamed Maple Wood with Saturated Water Steam

Polymers ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 217
Author(s):  
Ladislav Dzurenda ◽  
Michal Dudiak ◽  
Eva Výbohová
Keyword(s):  
Uv Radiation ◽  
Color Change ◽  
Color Space ◽  
Color Stability ◽  
Color Difference ◽  
Saturated Steam ◽  
Water Steam ◽  
Saturated Water ◽  
Red Color ◽  
Uv Lamp

The wood of maple (Acer Pseudopatanus L.) was steamed with a saturated steam-air mixture at a temperature of t = 95 °C or saturated steam at t = 115 °C and t = 135 °C, in order to give a pale pink-brown, pale brown, and brown-red color. Subsequently, samples of unsteamed and steamed maple wood were irradiated with a UV lamp in a Xenotest Q-SUN Xe-3-H after drying, in order to test the color stability of steamed maple wood. The color change of the wood surface was evaluated by means of measured values on the coordinates of the color space CIE L* a* b*. The results show that the surface of unsteamed maple wood changes color markedly under the influence of UV radiation than the surface of steamed maple wood. The greater the darkening and browning color of the maple wood by steaming, the smaller the changes in the values at the coordinates L*, a*, b* of the steamed maple wood caused by UV radiation. The positive effect of steaming on UV resistance is evidenced by the decrease in the overall color difference ∆E*. While the value of the total color diffusion of unsteamed maple wood induced by UV radiation is ∆E* = 18.5, for maple wood steamed with a saturated steam-air mixture at temperature t = 95 °C the ∆E* decreases to 12.6, for steamed maple wood with saturated water steam with temperature t = 115 °C the ∆E* decreases to 10.4, and for saturated water steam with temperature t = 135 °C the ∆E* decreases to 7.2. Differential ATR-FTIR spectra declare the effect of UV radiation on unsteamed and steamed maple wood and confirm the higher color stability of steamed maple wood.

scholarly journals A MONITORING METHOD OF COLOR DECAYING FOR COLORED PATTERNS IN ARCHITECTURAL HERITAGE

2019 ◽  
Vol XLII-2/W11 ◽  
pp. 1193-1198
Author(s):  
L. Zhang ◽  
J. Xie ◽  
L. Qin ◽  
Z. Liu ◽  
G. Liu
Keyword(s):  
Good Health ◽  
Color Difference ◽  
Health Condition ◽  
Architectural Heritage ◽  
Monitoring Method ◽  
Special Part ◽  
Color Differences ◽  
The Status ◽  
Set Up ◽  
Colored Pattern

<p><strong>Abstract.</strong> As a special part of architectural heritage, the colored pattern is not only artwork to decorate the architecture, but information reflecting specific historical era. So it has great cultural and artistic value. However, the colored pattern is one of the most sensitive types of cultural relics, which is sensitive to natural environment changes and highly vulnerable to erosion. In order to strengthen the protection of colored patterns in history architectures, it is necessary to monitor the status quo of them.</p><p>This work introduces a monitoring method of color decaying for colored patterns in architecture: set up the illuminants, adjust the illuminants, detect the color information and calculate the color difference. Based on the color difference by CIE DE2000 formula, the color decaying status of the pattern can be evaluated. The monitoring period should be at least three months.</p><p>About four years’ work has been carried out for colored patterns in the Long Corridor of the Summer Palace, and the color differences &amp;Delta;E<sub>00</sub> are about from 2 to 5, some can be over 9. In result, most colored patterns keep in good health condition. Color decaying happens every time and there are slight changes in most colored patterns. In 2nd quarter 2017, aware changes happened in nearly all the patterns. According to the color difference to evaluate the color decaying of the colored patterns, it is an efficient method to analyze the health status of colored patterns.</p>

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