Objective Colormaps for Minimizing Interpretation Bias in Science and Engineering

Abstract While working on the implementation of hygro-thermo-structural models for composite materials like those used in aircraft, we started noticing discontinuities in the fringe plots of the validation tests. This led us down a time-consuming path of debugging the implementation, that indicated that there were no problems with our numerical code. After further investigation we established the the issue emanated from the non-uniform nature of the colormap used to map the field variables. In researching the matter further we identified several contemporary attempts in establishing metric to judge the perceptual non-uniformity of colormaps. In this work we extend these attempts to encompass objective functions that allow for the automated generation of colormaps that minimize non-uniformity with the goal to reduce visual bias to the extent allowed by modern color theory and color standards. The objective functions are formulates on the basis of lightness, chromaticity, gamut completion, and desired color in both explicit and implict forms. We present several application examples and illustrate them based on typical benchmark data. We furthermore demonstrate the appearance of colormaps for the three types of color vision deficiency using simulated mapping. These studies are a precursor of refinement of the proposed framework towards more universal colormaps.