Multispectral image fusion using an improved wavelet transform

The purpose of multispectral image fusion is to merge information from multi-sensor and to improve abilities of information analysis and feature extraction. Discrete wavelet transform can offer a more precise way for image analysis than other multi-resolution analysis. It decomposes an image into low frequency band and high frequency band in different level, and it can also be reconstructed gradually in different level. But this method only decomposes low frequency band in a higher scale, so that it omits some useful details of the images. In this paper, we research an improved discrete wavelet transform. It decomposes high frequency band in higher scale which wavelet analysis does not do. We apply it on image data and give a fusion method in pixel level. Through merging remote sensing image of different wavebands from multi-sensor to a same object by applying method of improved wavelet analysis, we have obtained a fused picture. The method can fuse details of input image successfully, and display information of the each input image perfectly. Comparing with other image fusion methods, satisfactory result has been obtained by applying this method on both objective and subjective performance measure.