Remote sensing image fusion based on average gradient of wavelet transform

Image fusion is one of the important techniques to enhance image information of remote sensing. In order to adequately make use of all kinds of remote sensing images information such as SPOT Panchromatic and three-band Landsat multi-spectral images, a novel remote sensing image fusion scheme based on average gradient of wavelet transform is proposed. In the fusion processing, the fused approximate coefficients are obtained with weighted average method. For the bigger average gradient of the each decomposed approximate coefficient, we choose a big power gene. The other approximate coefficient chooses a small one. The fused detailed coefficients are obtained by setting each coefficient equal to the corresponding input image wavelet coefficient that has the greatest average gradient. The information entropy and the image clarity are proposed as the quantitative evaluation criteria to assess this proposed method and some other methods. The visual and statistical analyses of experimental results show that the proposed fusion method is more effective than the other methods mentioned in this paper.