Image Enhancement Based on the Contourlet Transform and Mathematical Morphology

Traditional methods for image enhancement cannot capture the geometric information of images and tend to amplify noise.To overcome the above enhancement issues,a new enhancement algorithm for image was proposed based on the Contourlet transform and mathematical morphology.The new algorithm decomposed image into approximation-coefficients and detail coefficients.Morphological dilation operations was used to distinguish noise form detail information according to dependencies of contourlet coefficients,then nonlinear mapping function was used to modify the contourlet coefficients.And the enhanced image were obtained by contourlet inverse transform.The experiments show that utilizing the proposed algorithm can enhances image detail and the signal to noise ratio.