Tie points based pixel-level compensation of misregistration for change detection

A method is proposed to process registered images to reduce the effects of registration noise in change detection. The proposed method is based on the pixel-level misregistration map and the gradients of the registered image. Thin plate spline (TPS) transform is selected to estimate the misregistration of each pixel using available tie points. For each pixel, the compensation is composed of two parts: a spatial part which compensates for the spatial registration error as pixel unit, and an intensity part which is calculated according to the subpixel part of misregistration and local gradients. The performance of the proposed method is illustrated using IKONOS panchromatic images and multitemporal multispectral images. Its independence of change detection method is experimented on three kinds of method: modified image difference, modified principle component analysis, and modified image ratio.