Kartografinių duomenų bazės atnaujinimas naudojant skaitmeninius palydovinius

Abstract

Research of different geometric transformation methods of IKONOS satellite images for removing distortion because of terrain relief is made. Unlike other commercial satellites, IKONOS does not provide detailed orbital information. For experiments the software OrthoEngine from PCI Geomatics is used. OrthoEngine uses an IKONOS specific satellite model for correction developed by Dr.Thierry Toutin at the Canada Centre for Remote Sensing. By using this module the methodology of orthorectification of IKONOS images by using GCP and Control points from KDB10LT is made. The Piece Wise Transformation is the most accurate method for elimination errors because of relief. The polynomial method of georectification is not enough accurate. By increasing the amount of GCP it is possible to reach more accurate results in Piece Wise Transformation, but it has very little effect on polynomial transformations. To achieve better results in the Piece Wise Transformation the elevations of GCPs and their locations should be taken into account. Orthorectified IKONOS images, without distortions because of terrain relief, are accurate enough material for updating Cartographical Database at the scale of 1:10 000.