Color image analysis by varying camera aperture

A set of images taken by systematically varying camera parameters conveys useful information which cannot or can hardly be extracted from a single image. This paper proposes a method to obtain the reliable color information, i.e. chromaticity and brightness from multiple color images taken with different aperture sizes, i.e. multi-iris color images. Based on the fundamental characteristics of optical systems, the authors first define an evaluation function to measure the reliability of color information at each pixel. They then synthesize a color image which consists of those pixels with the most reliable color information. In the experiments, they quantitatively examine the stability and reliability of color information in the synthesized image. They also demonstrate the usefulness of multi-iris color images: estimation of light source chromaticity and recovery of depth information from blurred edges