A contour-based approach to automatic and accurate registration of multitemporal and multisensor satellite imagery

An automatic approach for high accuracy registration of multisensor and multitemporal remote sensing images is presented. It avoids the use of ground control points, while exploiting the maximum reliable information in both images. Features to be used for image registration are those contours in both images that have been classified as coastline (reliable information). The automatic contour-based approach is summarized by the following steps: (i) reference image coastline extraction; (ii) sensed image gradient energy map estimation; (iii) contour matching, mapping function estimation and transformation of the sensed images. The algorithm proposed is automatic and of significant value in an operational context. Several experimental results for single sensor imagery (AVHRR) from different viewpoints and dates as well as multisensor imagery (AVHRR-SeaWiFS) have verified the robustness and accuracy of the proposed automatic registration algorithm, demonstrating its capability of registering satellite images of coastal areas within one pixel.