Artifact suppressed image enhancement through Bi Histogram equalization

This paper proposes a modification of Bi-Histogram Equalization (Bi-HE) method, for intensity saturation free contrast enhancement of images. The proposed method segments the input histogram into two sub-histograms using Otsu thresholding criteria. Prior to HE process, the narrow ranged segment are identified and allocated with full dynamic range. Then both of the equalized segments are combined together. In order to avoid intensity saturation problem, we have suggested a new normalization function. Simulation results show that, the proposed method preserves the image brightness more precisely and produces images with relatively negligible visual artifacts. Therefore, outperforms other contemporary methods both qualitatively and quantitatively.