Single Backlit Image Enhancement

Backlit images are from an excessive reflection of light being opposite to a capturing device. The existing image enhancement methods cannot be directly applied to the backlit images because they are not designed to enhance both broad light and dark regions simultaneously. Moreover, the techniques have several limitations about over-saturation or losing contrast. This paper presents a single backlit image enhancement method based on the novel full-piecewise non-linear automatic stretching, without input parameter provided by a user, e.g., gamma and so on. The computer simulation results confirm that the proposed approach can (i) undoubtedly reveal hidden details in the dark region; (ii) preserve features and color of common and light (over-brightness) regions, and (iii) increase a local contrast of dark areas. The proposed approach tested on Li's backlit image database and several backlit images from commercial devices. The simulation results demonstrate the efficiency of the proposed approach and its advantages over the cutting-edge backlit image enhancement methods in perceptual quality.