Measurement of the Optimum Surround Lightness: the Case of Reflective Stimuli

摘要

Many applications showed that contrast of the image depends on brightness of the surround. For this reason, our previous research has attempted to measure the change in perceived image contrast for LCD under a wide range of surround luminance levels. The results showed that the perceived image contrast change with surround luminance as a band-pass function against surround ratio (SR) and the maximum contrast was found near SR of 1. The current study aims to verify the surround effect for reflective stimuli such as prints. Various backgrounds were simulated by change lightness of the surrounding area in the paper. In total, ten background levels including white paper were studied. In total, ten surround levels including white paper were studied. The maximum lightness of surround is 100 (paper white) and 10 lower levels were rendered with equi-distance in lightness. A set of paired comparison experiments was conducted based on simultaneous haploscopic viewing condition in order to compare the perception of image contrast under two different surrounds at the same time. The highest perceived image contrast was also found when SR=1 so it confirms our previous results based on emissive stimuli.