Perceptual Contrast Estimation for Color Edge Detection

Color edge detection is an important research task in the field of image processing. Efficient and accurate edge detection will lead to increase the performance of subsequent image processing techniques, including image segmentation, object-based image coding, and image retrieval. To improve the performance of edge detection while considering that human eyes are ultimate receiver of color images, the perceptually insignificant edges should avoid over-detecting. In this paper, a color edge detection based on the adaptively perceptual color contrast is proposed. The perceptual color contrast is defined as the visible color difference across an edge in the uniform color space. A perceptual metric for measuring the visible color difference of a target color pixel is defined by utilizing the associated perceptually indistinguishable region. The perceptually indistinguishable region for each color pixel is estimated by the design of an experiment that considers the local property due to local changes in luminance. Simulation results show that most of perceptually insignificant edges are suppressed through the proposed perceptual metric. The performance of the proposed edge detection scheme is superior to that of the edge detection scheme without considering visual properties.