A New Method to Fusion IKONOS and QuickBird Satellites Imagery

The modern remote sensing imaging sensors, like those in the IKONOS and QuickBird satellites, are capable of generating panchromatic images with about one meter spatial resolution. The principal objective of fusion in remote sensing is to obtain images that can combine the spectral characteristic of the lowresolution multispectral images with the spatial information of the high-resolution panchromatic images. Traditional fusion methods, such as IHS, PCA and Brovey, can reach good spatial resolution results, but often cause spectral distortion problems. In the literature, it is possible to find some image fusion methods using frequency domain processing, like wavelet or Fourier transform. Although they preserve good spectral information, their spatial visual effects are not satisfactory or limits to three the number of spectral bands used in the fusion process. In this paper, a method based on Fourier transform is proposed in order to obtain good spatial and spectral resolutions, without limiting the number of bands. Quantitative measurements were applied to evaluate the quality of four fusion methods (IHS, IHS enhanced by Fourier transform, wavelet-based and the proposed one) in IKONOS and QuickBird images. The results have shown that the proposed method can keep almost the same spatial resolution as the panchromatic images, and its spectral effect is well preserved.