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

摘要

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.