Research And Implementation On Image Enhancement Methods

Image enhancement technology plays a very important role to improve image quality in image processing. By enhancing some information and restraining other information selectively it can improve image visual effect and transform an image to another form which adapts to human observation or computer analysis and processing better.This paper makes an exhaustive study of some enhancement methods such as gray scale transformation, histogram equalization and fuzzy enhancement. It puts forwards correspondence methods to solve some defects during the course of image enhancement.Aiming to the key problem of how to divide gray scale intervals, this paper puts forward a method called segmental linear transformation based on region segmentation. It accelerates the process of adjusting gray intervals and is an efficient method.In order to adapt to image local regional brightness characteristic, this paper puts forward a method called histogram equalization based on parabola modification. It can adjust the brightness and enhance the contrast of local region. At the same time it puts forward a method of how to select optimum parameters.By adjusting gray level values of pixels after equalization this paper puts forward a method called histogram equalization of preserving gray levels. It can make gray level layers more abundant and dispel the amalgamation of gray levels to some extent.This paper improves traditional fuzzy enhancement method. It uses sine membership function for fuzzy enhancement. So it avoids a large amount of the missing of gray scale information. At the same time it accelerates the selection of the optimum parameters. On the basis of fuzzy enhancement gray scale linear transformation is used to improve image enhancement result further.Experiences show that the methods of this paper obtain better enhancement...