To improve conventional methods for contrast enhancement

this paper presents a novel approach based on wavelet transform and fuzzy logic.Firstly

normalize the low contrast image to reduce the effects of different illuminations.Then choose a specific wavelet transform to convert the normalized image and obtain wavelet coefficients.The low-pass coefficients are fuzzified by the linear operator and use both the global and local information to define and enhance the image's global contrast.For high-pass coefficients

utilize nonlinear operator to enhance the details of images.Finally

the inverse wavelet transform is applied to map the result into space domain. Experimental results of the proposed approach and other conventional methods are compared and analyzed to demonstrate that the proposed approach is very effective in enhancing the low contrast image without over-enhancement and under-enhancement.