Abstract
Geometric correction accuracy of IRS-1D panchromatic imagery was investigated using GPS- and 1 : 25 000 scale topographic map-derived control points. The differentially corrected GPS-derived coordinates provided markedly more accurate results than did uncorrected handheld GPS- and map-derived GCPs. The rms error value of differentially corrected GPS-derived control points based on second-degree polynomial was in the order of ±3 m. Geometric corrections made with second-degree polynomials, using both the map- and uncorrected handheld GPS-derived control points, yielded rms error values in the order of ±5 m. The results revealed that the uncorrected handheld GPS-derived control points can be a valuable alternative to planimetric control for geometric correction of IRS-1C/D panchromatic imagery with one-pixel size accuracy.
Acknowledgments
The authors would like to thank HAT GIS Company which has supplied IRS-1D PAN imagery for this research. The helpful comments of two anonymous reviewers have helped to improve the manuscript and are gratefully acknowledged.