Image enhancement method based on fractional wavelet transform

The characteristic of the subband coefficients of the discrete fractional wavelet transform (DFRWT) vary with the change of the order p should be utilized in this paper. The original image is decomposed by DFRWT in different p order near p=1, and the mode subband coefficients have changed slightly with the comparison of DWT(p=1). In order to make the result of image enhancement selective, the paper presents a new image enhancement technique based on DFRWT and adaptive threshold algorithm. Experimental results show that the proposed methods effectively promote the enhancement effect in details compared to the result of the order p=1, objective evaluation is of Contrast Improvement Index(CII) are obviously improved.