Accuracy Assessment for A Stereo Pair of CARTOSATI Images by Used of GCP Points
Melika Sadat Fardkarimi
Due to increasing number of High Resolution Satellites, the production of ortho image and 3D maps from these images are becoming increasingly important. In order to do so acquiring Ground Control Points (GCP) is necessary. Higher quality aerial or satellite imagery will not replace the need for GCP. In fact, ground control point collection becomes increasingly more important as image quality improves. Fortunately, collecting ground control point is now a much faster, more accurate, and cost-effective process thanks to the use of GPS but the proper number of control points still is an issue. In this article, the P5 imagery from IRS series has been especially used because of 2.5-meter resolution and their affordable price. In order to orient satellite imagery with respect to the earth, ground control points (GCP) are designed and created in the region of interest. Having a stereo pair of images with near to full coverage; triangulation has been used for point distribution and block adjustment. The main calculations were performed by local triangulation software and we used a progressive control point number approach. Starting with a single control point, the amounts of vertical and horizontal accuracies are calculated and tabulated.