Direct mapping between histograms: an improved interactive image enhancement method

In the traditional algorithm, two steps are needed to construct a mapping function from an original histogram to an arbitrarily specified histogram. One of the problems observed with the traditional histogram specification technique is the contouring effect in the general image. A one-step histogram specification method is presented to overcome some weaknesses of the traditional method. First, the cause of the contouring effect in the traditional two-step histogram transformation method is analyzed. Then, the one-step histogram specification algorithm is developed to avoid this problem. From the analysis and experiment results, it can be seen that the proposed one-step histogram specification has reduced the contouring effect which was caused by the traditional two-step method. The advantage of the presented approach is to minimize the local errors between the desired histogram and the resulting histogram.<>