Studies on the Correction of Geometric Distortion of SPOT HRV Image Data

Abstract

Experiments on correction of geometric distortion of SPOT HRV image data based on a polynomial and ground control points indicate following features. In case of the Level-1A SPOT HRV image data the optimum degree of the polynomial is the 2-nd degree both for a latitude-longitude coordinate system and a plane rectangular coordinate system, while in case of the Level-1B data the optimum degree is the bilinear for the latitude-longitude coordinate system and linear for the plane rectangular coordinate system.
A computer program for the correction of geometric distortion has been developed in which ground control points are not available. The result of the verification of the program in reference with well defined check points indicates that although an absolute error is large the standard deviation of the error is within 1 pixel for the multispectral mode data and within 2 pixels in case of the panchromatic mode data.
The ground control points and check points utilized in the studies are those on the assumed standard height and are derived from the standard map published by Geographical Survey Institute of Japan, the satellite positions and the information of the geoid.