Efficiently evaluating the effect of color gamut and spectral bandwidth on observer metamerism in high dynamic range displays

다국어 초록 (Multilingual Abstract)

Observer metamerism (OM), which likely causes potential issues in high dynamic range (HDR) displays due to those formidable peak luminance and color gamut required, is examined in this work using simulations. The simulations focus on investigating how OM in HDR displays would vary with chromaticity gamut and peak luminance level changes, proposing a new OM index, OMM. The effects of additional factors noteworthy on OM, such as reference white level, age, and spectral characteristics, are discussed. Finally, a simple metric capable of predicting observer metamerism between displays with less computational complexity, OMMN, is introduced. The simulation results showed that observer metamerism magnitudes between displays tend to depend on the similarity in spectral bandwidth between paired displays, in addition to the fact that narrow‐band primary displays generally cause larger metameric failures. Besides, the effect of changes in peak luminance on observer metamerism was found to be relatively small, increasing OMM by 7%–8% when peak luminance doubles. Notably, the proposed efficient metric OMMN outperforms metrics based on spectral similarity by also factoring in inter‐observer variability. In addition, the proposed metric's performance with 10 categorical observers, OMMN, 10, is nearly as good as that with thousands more computations. OMMN, 10 is recommended as a reliable and efficient metric to evaluate OM between HDR displays.
The effect of spectral bandwidth of HDR display primaries on observer metamerism is quantified through simulations of thousands of observers and color samples, showing the slight effects of peak luminance and diffuse white levels. A computationally efficient metric—OMMN, 10—is proposed to predict the degrees of observer metamerism between displays, using 10 categorical observers and a single sample color (D65 at 50 cd/m2). A new metric, OMMN, 10 using 10 Categorical observers and a single color (D65 with 50 cd/m2), which is computationally efficient, is proposed to predict the degrees of observer metamerism between displays. As shown below, this metric accurately predicts the degrees of observer metamerism between displays computed using about 1000 observers and 5000 colors.