CIE uniform chromaticity scale diagram for measuring performance of OSA-UCS ΔEE and CIEDE00 formulas

The CIE recommended uniform chromaticity scale (UCS) diagram based on the CIELUV is used to evaluate the non-Euclidean approximate form of CIEDE2000 and the Euclidean ΔE_E colour difference formulas for measuring the visual data. Experimentally observed visual colour difference data in terms of supra threshold ellipses are plotted in the CIELUV u*, v* diagram. Similarly, equi-distance ellipses of two formulas are computed and plotted in the same diagram. Performance of these formulas are evaluated by calculating the matching ratio between observed and computed ellipse pairs. Various statistical tests are done for these ratio values. It is found that there is no significant difference between the complex non-Euclidean approximate form of ΔE₀₀ and the simple Euclidean ΔE_E.