Outdoor image enhancement: Increasing visibility under extreme Haze and lighting condition

This paper addresses the problem of image enhancement thereby enhancement of scene visibility in outdoor images. Visibility is a very important issue in case of computer based surveillance, crime analysis, driver assistance system design etc. The most important challenge related to visibility is the atmospheric haze and poor lighting. The problem becomes more challenging if haze is too dense and lighting during night is extremely poor. In this paper an automatic degradation detection and restoration algorithm has been proposed, which detects the type of degradation using the distribution of the scene, then uses the hybrid dark channel prior based haze removal algorithm if the image is degraded due to atmospheric haze only, otherwise it computes the image negative first and then uses the hybrid DCP to resolve the problem. The algorithm has been tested in many situations and the results obtained are satisfactory as comparison to the existing algorithms.