Abstract:
Resolution enhancement (RE) schemes (which are not based on wavelets) suffer from the drawback of losing high frequency contents (which results in blurring). Here we propose the Adaptive wavelet- transform-based (AWT) for resolution Enhancement in satellite images. A satellite input image is decomposed by DT-CWT (which is nearly shift invariant) to obtain high-frequency sub bands. The high-frequency sub bands and the low-resolution (LR) input image are interpolated using the Lanczos interpolator. The high frequency sub bands are passed through an NLM filter to cater for the artifacts generated by DT-CWT (despite of its nearly shift invariance). The filtered high-frequency sub bands and the LR input image are combined using inverse DT-CWT to obtain a resolution-enhanced image.We propose DWT for sub band interpolation process and we compare the resolution of satellite image enhancements using Wavelet Methods with ARSIS methods.
Keywords: Dual-tree complex wavelet transform (DT-CWT),Lanczos interpolation, resolution enhancement (RE), shift variant, PAN sharpening methods,ATWT,MTF.