Fusing remote sensing images using à trous wavelet transform and empirical mode decomposition

À trous wavelet transform (AWT) and empirical mode decomposition (EMD) are two distinct methods used for analyzing nonlinear and nonstationary signals. In this paper, a combination of AWT and EMD is proposed as an improved method for fusing remote sensing images on the basis of the framework of AWT-based image fusion. The principle consists of performing a multiresolution decomposition on high resolution panchromatic image (HRPI) using AWT. The approximation component and low resolution multispectral image (LRMI) are fused through an intrinsic mode functions (IMFs) based model. Subsequently, the sharpening approximation component produced is substituted for the old one. High resolution multispectral image (HRMI) is then obtained through an inverse AWT (IAWT). QuickBird images are used to illustrate the advantage of this method over the traditional AWT and EMD based methods both visually and quantitatively.