Optimization of geometric correction of Landsat TM images using digital elevation model

In the conventional scheme of geometric correction of satellite imagery, a number of ground control points (GCPs) are used to determine the transform equation statistically. The selection of GCPs on the map is usually arbitrary, and the identification and measurement of GCPs on the satellite image need intensive manual labor unless they are determined automatically. In this paper, we propose a new method for determining the optimum transform equation without selecting the GCPs. The correlation between the simulated shading relief image and the ortho-rectified satellite image is used to evaluate the geometric transform equation and to optimize its parameters. It is shown that optimization on scene center displacement is sufficient for relatively narrow area (18 km by 18 km) with sub pixel accuracy.