A new adaptive contrast enhancement algorithm for infrared images based on double plateaus histogram equalization

In infrared images, detail pixels are easily immerged in large quantity of low-contrast background pixels. According to these characteristics, an adaptive contrast enhancement algorithm based on double plateaus histogram equalization for infrared images was presented in this paper. Traditional double plateaus histogram equalization algorithm used constant threshold and could not change the threshold value in various scenes, so that its practical usage is limited. In the proposed algorithm, the upper and lower threshold value could be calculated by searching local maximum and predicting minimum gray interval and be updated in real time. With the proposed algorithm, the background of infrared image was constrained while the details could also be enhanced. Experimental results proved that the proposed algorithm can effectively enhance the contrast of infrared images, especially the details of infrared images.

► An adaptive contrast enhancement algorithm for infrared images was presented.
► Better estimation for the upper threshold is obtained using a slide window.
► The lower threshold is accurately calculated by the accumulative statistic value of the histogram.
► The upper and lower thresholds can be updated in real time.
► Better performance in image contrast enhancement compared to traditional algorithms.