Performance of Recent Color Difference Equations around a CIE Blue Color Center

摘要

In 2004, an ISO committee found that insufficient data were available to make a decision on whether to recommend CIEDE2000 in place of DE_(CMC). However, a provisional work item was initiated [1] to test independently the performance of the major color difference formulae specifically in the blue and near neutral regions. Accordingly, the objective of this work was to develop a new, comprehensive visual dataset around one blue color center, and to compare the performance of all the major formulae against the new dataset.rnA total of 5148 assessments using 66 textile sample pairs with small color differences (DE<5) were obtained. Each pair was visually assessed by 26 color normal observers in three separate sittings using a gray scale method. A third-degree polynomial equation was used to convert gray scale ratings to visual differences (DV). The performance of major formulae was evaluated based on a correlation coefficient (r) and the PF/3 measure at two lightness weights (K_L or l) of 1 and 2. Correlation coefficients of 0.91, 0.92 were obtained for CIEDE2000 at K_L of 1 and 2, which were the highest amongst the color difference equations examined although at K_L (or l)=2, CIEDE2000 and BFD performed comparably. Using the PF/3 metric the BFD equation gave the best results at both lightness scales (37.46, and 42.46 respectively), however, at K_L or l =2, all major equations gave approximately the same performance.