Increasing the Complexity of the Illumination May Reduce Gloss Constancy

Area of Science:

• Computer Vision
• Perceptual Science
• Computer Graphics

Background:

• Surface glossiness perception is crucial in computer graphics and computer vision.
• Understanding how illumination geometry affects perceived glossiness is key to realistic rendering.

Purpose of the Study:

• To investigate the impact of gradual changes in illumination geometry on perceived surface glossiness.
• To identify specific illumination features that influence glossiness perception.

Main Methods:

• Utilized computer-generated 3D scenes with controlled illumination from three point light sources.
• Conducted psychophysical experiments where subjects matched perceived glossiness by adjusting surface microscale smoothness.
• Analyzed the role of highlight overlap and global image statistics.

Main Results:

• Small variations in light field geometry induced significant changes in perceived glossiness.
• Perceived glossiness is modulated by the microscale smoothness of the surface.
• Perceptual underestimation of glossiness occurs when highlights merge due to large overlap.

Conclusions:

• Illumination geometry, particularly highlight overlap, is a critical factor in perceived glossiness.
• The findings provide insights for realistic rendering and visual perception models.
• A linear model based on image statistics showed some predictability for smoothness settings.