Contourlet-Based Image Fusion using Information Measures

The fusion of high-spectral but low spatial resolution multispectral and low-spectral but high spatial resolution panchromatic satellite images is a very useful technique in various remote sensing applications. Recently, some studies showed that wavelet-based image fusion methods provide a high quality spectral content of fused images. However, the spatial resolution of waveletbased fused images is less than the Brovey-, HIS-, and PCA-based fusion methods. This is mostly due to the fact that wavelet transform cannot efficiently represent the singularity of linear/curve edges contourlet transform which better represents edges. Since edges play a fundamental role in image understanding, one good way to enhance spatial resolution is to enhance the edges. Wwe have computed an automatic threshold for discarding weak edges of panchromatic satellite images using an information measure. Strong edges were then fused to form reliable multi-spectral images. We have tested the proposed approach on IRS satellite images and compared our results with other existing methods.