Color Quality Evaluation Research Articles

22‐3: Invited Paper: Color Quality Evaluation Methods for (Tunable) White‐Light Sources

Solid‐state lighting has enabled configurable and tunable white‐light sources. The available specification criteria, such as CCT, ΔuV, and CRI, are insufficient to characterize the color quality properties for these emerging technologies. An overview of new characterization methods will be presented with their potential for successful adoption by the lighting industry.

Color Quality Evaluation of High Color Rendering White LEDs According to Phosphor Types and Composition Ratio

Color Quality Evaluation of High Color Rendering White LEDs According to Phosphor Types and Composition Ratio

光柱镭射纸及其印刷品的颜色质量评价方法

光柱镭射纸及其印刷品的颜色质量评价方法

Preference for appearance of Chinese complexion under different lighting

The method for evaluating the colour rendering of light-emitting diode sources is controversial, especially for the appearance of human complexions. A psychophysical experiment was conducted using Chinese models to examine the effect of various illumination settings, characterized by two levels of preferred skin colour index and four levels of correlated colour temperature, on preference for the appearance of the Chinese complexion. Results showed that the preferred skin colour index was an effective indicator. Taking incomplete colour adaptation into account, the preferred skin colour index was recalculated and shown to be the best colour rendering index for the appearance of the Chinese complexion. This research examined the concept of preferred skin colour index for Chinese women. This can supplement other colour quality evaluation methods, and shows promise for commercial lighting applications.

Color spaces of safflower (Carthamus tinctorius L.) for quality assessment

ObjectiveIn this study, safflower (Carthamus tinctorius L.) was taken as a representative example to examine the application of color characteristics to evaluate quality. MethodsA computer vision system was established for the objective and nondestructive assessment of color using image processing algorithms. Color parameters were investigated based on the RGB, L*a*b and HSV color spaces. The content of hydroxysafflor yellow A (HSYA), a major bioactive constituent of safflower, was determined by high-performance liquid chromatography. The relationship between HSYA content and color values was investigated by Pearson correlation analysis. A multiple linear regression model was established to predict the HSYA content from color values. ResultsThe red color and lightness of safflower were found to be significantly related to HSYA content. The prediction equation obtained by multiple regression was reliable with an R2 value of 0.805 (P < .01). ConclusionThe results suggest that the computer vision technique could be used as a promising and non-destructive technology for color measurement and quality evaluation of CHM.

Evaluation of Color, Lipid Oxidation and Microbial Quality in Meatballs Formulated with Bee Pollen During Frozen Storage

In this study, the color, lipid oxidation and microbial quality of meatballs formulated with different levels of bee pollen were investigated during frozen storage. Meatballs were prepared with different levels (0, 1.5, 3.0, 4.5 and 6.0%) of bee pollen, and stored at −20 ± 1C for 90 days. The phenolic content and antioxidant activity of bee pollen were 309.21 mg GAE/100 g and 2.23 mmolTrolox/g, respectively. The pH values of meatballs were affected by both pollen addition and storage period (P < 0.05). The redness values of meatballs decreased with pollen addition but yellowness, chroma and hue angle values increased. These values also changed significantly during storage. TBARS values of samples increased during storage, but the addition of pollen retarded the lipid oxidation. Also, the addition of pollen inhibited the microbial growth in meatballs. The results suggest that bee pollen can be successfully used as a natural antioxidant and antimicrobial agent in meatballs. Practical Applications Frozen storage of foods is one of the important preservation methods for extending shelf life. During frozen storage, there is generally no opportunity for the growth of microorganisms if recommended temperatures are maintained, but chemical and biochemical reactions such as lipid oxidation and discoloration are not completely inhibited. These are the major causes of deterioration in meat quality during frozen storage. Use of antioxidants, therefore, is important to prevent economic loss. Bee pollen is a valuable and highly recognized source of antioxidants and antimicrobials. Therefore, this article deals with the use of bee pollen as an antimicrobial and antioxidant agent in meatballs.

Colour quality evaluation of natural objects based on the Feeling of Contrast Index

Past studies have shown that the Feeling of Contrast Index (FCI) correlates with preference in some circumstances, but the exact relationship is not clear and may differ among visual conditions and targets. This paper presents a psychophysical experiment in which 70 observers evaluated the colour quality of natural objects under different spectral power distributions with different values of FCI but the same correlated colour temperature (3000 and 5000 K). Results show that FCI holds a nearly perfect linear correlation with vividness ( r = 0.976); unnaturalness associated with enhanced vividness rendered by excessively high FCI deteriorates preference. These effects are independent of correlated colour temperatures, but are dependent upon the visual targets used because of limitations in the derivation of FCI. Compared to other metrics, FCI can characterise vividness under a light source.

Development of novel fruit bars by utilizing date paste

Abstract In this study, we aimed to produce novel fruit bars by using two different types of popular date cultivars (Nabtat Ali and Sukkari). Standard procedures were adopted for preparing the fruit bar. However, in this study, products were devoid of any sweet additives, as dates are rich in natural sugars. Various analysis (proximate composition, total phenolics content, antioxidant activity, colour, textural profile, and sensory quality evaluation) were performed to evaluate the overall virtues of date based fruit bar. Results showed date fruit bars to be rich in protein, fat and carbohydrates with good energy values. However, decrease in total phenolics and inhibition of DPPH radical was observed in fruit bars compared to raw dates. Texture wise, products had high fracturability, indicating easy to bite and chew nature, thus rendering it suitable for elderly people and small children. Results of sensory quality evaluation indicated dates to have excellent potential to be converted into fruit bars. Results generated in this study suggest date-based fruit bars may be expected to fulfill the requirements of health conscious consumers. It is anticipated that this novel food product will attract better marketability at the international level.

Memory colours and colour quality evaluation of conventional and solid-state lamps

A colour quality metric based on memory colours is presented. The basic idea is simple. The colour quality of a test source is evaluated as the degree of similarity between the colour appearance of a set of familiar objects and their memory colours. The closer the match, the better the colour quality. This similarity was quantified using a set of similarity distributions obtained by Smet et al. in a previous study. The metric was validated by calculating the Pearson and Spearman correlation coefficients between the metric predictions and the visual appreciation results obtained in a validation experiment conducted by the authors as well those obtained in two independent studies. The metric was found to correlate well with the visual appreciation of the lighting quality of the sources used in the three experiments. Its performance was also compared with that of the CIE colour rendering index and the NIST colour quality scale. For all three experiments, the metric was found to be significantly better at predicting the correct visual rank order of the light sources (p < 0.1).

Research on Quality Evaluation Method of Color Reproduction of Ink-jet Image

The color evaluation of ink-jet based on simulation of human vision system by S-CIELAB color spacee is presented in this paper. Dark tone, high-light tone, neutral grey, skin color, color gamut and memory color are used as six quality factors which affect inkjet's color reproduction, and the parameter weight of color evaluation is determined by fuzzy hierarchy analysis. Then, a parameter model of fuzzy evaluation which is about the color reproduction quality of ink-jet is established. The experimental results show that color quality evaluation parameter &#x394;EIC which is proposed in this paper is more prise than traditional&#x394;E00 in the color quality evaluation of ink-jet. The methord in this paper can maintain consistency of the subjective and objective evaluation.

Evaluation of color quality of crude soybean oil — some data and difficulties incident to developing a suitable test for off grades

Oil and SoapVolume 22, Issue 1 p. 13-22 Article Evaluation of color quality of crude soybean oil — some data and difficulties incident to developing a suitable test for off grades An elaboration of some aspects of the bleach test committee report and of other unpublished recent technical committee work Correction(s) for this article Evaluation of color quality of crude soybean oil—Some data and difficulties incident to developing a suitable test for off grades Egbert Freyer, Volume 22Issue 3Oil and Soap pages: 80-80 First Published online: March 1, 1945 Egbert Freyer, Egbert Freyer Spencer Kellogg and Sons, Inc., Buffalo, New YorkSearch for more papers by this author Egbert Freyer, Egbert Freyer Spencer Kellogg and Sons, Inc., Buffalo, New YorkSearch for more papers by this author First published: 01 January 1945 https://doi.org/10.1007/BF02637371Citations: 2 Paper presented at the Spring meeting of the A. O. C. S. at New Orleans, May, 1944. Opinions expressed in this paper do not necessarily represent those of the Bleach Test Committee. An erratum to this article is available at http://doi.org/10.1007/BF02639937. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Citing Literature Volume22, Issue1January 1945Pages 13-22 RelatedInformation

Evaluation of color quality of crude soybean oil—Some data and difficulties incident to developing a suitable test for off grades

Evaluation of color quality of crude soybean oil—Some data and difficulties incident to developing a suitable test for off grades