Regularization Explanation of Adjustable Histogram Equalization and Its Improvement
WU Cheng-mao · Dianzi xuebao · 2011
In view of histogram equalization regarded as typical ill-posed problem,the adjustable histogram equalization method is explaned by regularization theory,and its improvement is proposed in order to obtain the better effect of image enhancement.Firstly,the objective function of adjustable histogram equalization method is simplified and explaned by means of information energy as a regular item.Secondly,in consideration of the dual relationship between information entropy and information energy,the new adjustable histogram!equalization model based on information entropy as regularization is obtained.Thirdly,the regular item coefficient choosing method of adjustable histogram equalization is presented by means of information entropy or energy of gray levels probability distribution.Finally,the adjustable histogram equalization improvement method based on modifying cumulative probability of gray levels is proposed in order to improve the image enhancement effect of traditional histogram equalization method.Experimental results show that the improvement method of adjustable histogram equalization is effective.