A Network-Based Radiometric Equalization Approach for Digital Aerial Orthoimages

Digital aerial orthoimages have been widely used in surveying, mapping, geographic information systems, visualization, and other applications. However, when producing digital aerial orthoimages, radiometric equalization over large areas is often a most time-consuming and costly process and has become a bottleneck. This letter presents a network-based radiometric equalization approach to eliminate the radiometric differences between images. The network is constructed using the area Voronoi diagrams with overlap and is based on the topological relationship of the constructed network; transferring paths between images are determined, and a global-to-local strategy is used to improve the algorithm, both in its global and local performance. Digital aerial orthoimages from both film-based and digital cameras are used to evaluate the performance of the presented algorithm.