Automatic Extraction of Control Points for the Registration of Optical Satellite and LiDAR Images

A novel method for automatic extraction of control points for the registration of optical images with Light Detection And Ranging (LiDAR) data is proposed. It is based on transformation-invariant detection of salient image disks (SIDs), which determine the location of control points as the centers of the corresponding image fragments. The SID is described by a feature vector, which, in addition to the coordinates and diameter, includes intensity descriptors and region shape characteristics of the image fragment. SIDs are effectively extracted using multiscale isotropic matched filtering-a visual attention operator that indicates image locations with high-intensity contrast, homogeneity, and local shape saliency. This paper discusses the extraction of control points from both natural landscapes and structured scenes with man-made objects. Registration experiments conducted on QuickBird imagery with corresponding LiDAR data validated the proposed approach.