Rectification of satellite imagery from Google Earth: application for large scale city mapping

Abstract

The rectification of high resolution digital aerial images or satellite imagery for large scale city mapping is modern technology that needs well distributed and accurate defined control points. The digital satellite imagery, obtained when using widely known software Google Earth, can be applied for accurate city maps construction. The method named “Five control points” is suggested for imagery rectification introducing Prof. Ruan Wei (Tong Ji University, Shanghai) algorithm. Image rectification software created on the base of suggested algorithm can correct images deformation with required accuracy, is reliable and keeps advantages in flexibility. Experimental research for testing applied technology has been executed using GeoEye imagery from Google Earth over city Vilnius. Orthophoto maps at scales of 1:1000 and 1:500 are generated referring to “Five control points” methodology. Reference data and rectification results are checked comparing with results from digital aerial images processing using digital photogrammetry approach. The image rectification process applying investigated method takes short time (about 4–5 minutes) when using only five control points and accuracy of created models satisfies requirements for large scale mapping.