The Effect of Color Contrast on the Visual Clarity of Images of Complex Indoor Environments

Color contrast creates visual interest, increases attention, and enhances legibility in the indoor environment. Past studies have suggested that color contrast enhances visual clarity due to the color opponency mechanism of the visual system, especially when two opposing colored samples are seen side by side, such as red–green or yellow–blue. However, these studies were limited to solid single-colored samples, which falls short on representing the built environment with its complex distributions of colors and objects. This study explores the validity of the “color contrast–visual clarity” hypothesis for complex images of indoor built environments. Twenty images of indoor environments were selected from an image database to represent a wide range of colorfulness and spatial complexity (ranging from simple to complex). Forty new images were generated by increasing the colorfulness of either the red and green or blue and yellow sections of the original 20 images using an image editing software. Forty participants assessed the visual preference, clarity, colorfulness, and complexity of the 60 images. No statistically significant difference was found between red–green or yellow–blue enhanced images and original images. However, an observable trend indicated a linear relationship between visual clarity and colorfulness. In addition, participants preferred saturated images over original images. While the findings suggest potential trends, the lack of significant effects warrants cautious interpretation, and further research is needed to explore the impact of color contrast in more controlled settings.