Plateau limit‐based tri‐histogram equalisation for image enhancement
Abhisek Paul, Paritosh Bhattacharya, Santi P. Maity, Bidyut Kumar Bhattacharyya · IET Image Processing · 2018
An adaptive plateau limit‐based histogram equalisation algorithm is suggested to enhance digital images. Histogram of the image is clipped with a plateau limit to avoid over enhancement. The plateau limit is derived from the average of the mean and the median intensity values to offer the improved enhancement. Clipped histogram is subdivided into three parts, using histogram subdivision limit parameters that are calculated on the basis of the standard deviation of the image. Histogram of individual sub‐image is equalised independently and then combined into a single enhanced image. Experimental results demonstrate that the proposed plateau limit‐based tri‐histogram equalisation algorithm enhances the image quality. Compared with the other traditional plateau and non‐plateau limit‐based histogram equalisation algorithms, quantitative and visual quality assessments effectively validate the superiority of the proposed algorithm.