3D GEOPOSITIONING ACCURACY ANALYSIS BASED ON INTEGRATION OF QUICKBIRD AND IKONOS IMAGERY

Abstract

Stereo high-resolution satellite imagery, such as Space Imaging’s IKONOS (1 m resolution) and DigitalGlobe’s QuickBird (submeter resolution), can provide accurate three-dimensional (3D) mapping products. Based on the rational function model, this study investigated the integration of IKONOS and QuickBird images. One pair of stereo IKONOS images and one pair of stereo QuickBird images, collected in the same region, were used in the study. The 3D geopositioning accuracy from a single IKONOS image and a single QuickBird image was compared with those from stereo IKONOS images, stereo QuickBird images, and the combination of the images. First, 3D geopositioning accuracies of stereo IKONOS and QuickBird images were computed respectively by an improved rational function model with four ground control points. It was found that the accuracy of IKONOS images is at the one-meter level and that of QuickBird is at the sub-meter level, in the same order of their image resolutions. All four images from both pairs were then used together based on the rational function model. The calculated accuracy is at the sub-meter level. In data integration, the imaging geometries of both pairs of images were examined. The feasibility and accuracies of combinations of single IKONOS and single QuickBird images were investigated. The results show that, with the proper triangulation angle, a single IKONOS image and a single QuickBird image can form a stereo image pair that can provide sub-meter 3D geopositioning accuracy. 1