The Effect of Texture on Perceived Memory Color Quality

Abstract

We learn the color of objects and scenes through our experience in everyday life. The colors of things that we see more frequently are defined as memory colors. These help us communicate, identify objects, detect crop ripeness or disease, evaluate the weather, and recognize emotions. Color quality has become a priority for the smartphone and camera industry. Color quality assessment (CQA) provides insight into user preference and can be put to use to improve cameras and display pipelines. The memory color of important content like human skin, food, etc. drives perceived color quality. Understanding memory color preference is critical to understanding perceived color quality. In this study, grass, sky, beach sand, green pepper, and skin were used to perform memory color assessment. Observers were asked to adjust patches with four different textures, including computed textures and real image content, according to their memory. The results show that observers adjust the image patch most consistently. In cases where the artificially generated textures closely resembled the real image content, particularly for the sky stimulus, which resembled a flat color patch, participants were able to adjust each sample more consistently to their memory color. To understand the relation between memory color and the color quality preference for camera images, a second experiment was performed. A paired comparison for familiar objects was performed with five different color quality images per object. Two of these five images were rendered from the results of the memory color assessment experiment. Additional images included were the three most preferred color quality images from a rank order CQA. This experiment was performed by naïve observers and a validation experiment was also performed by Munsell Color Science Laboratory observers. The results for color image rendering preference for each memory image content vary. The results show that for most of the colors, people prefer the top three camera color quality images used from the rank order CQA. For grass, however, the color quality preference is highest for one of the memory color assessment results. In this experiment, images rendered to reflect memory color do not match observer preference.