Correction of Distortions in YG-12 High-Resolution Panchromatic Images

Abstract

Design deficiencies and hardware limitations cause a number of issues with the images acquired by Chinese satellites launched before 2012, such as YG-12. The geometric quality of the images recorded by YG-12 cannot match its high resolution because of serious time-synchronization errors and interior distortions. To improve the geometric quality of YG-12 images, this paper proposes a method of interior calibration for the YG-12 panchromatic sensor. In addition, an innovative method is proposed to eliminate time-synchronization errors using parallel observations of the panchromatic sensor onboard YG-12. The experimental results indicate the interior parameters of the panchromatic sensor are determined with an accuracy of better than 0.32 pixels, and seamless mosaic images can be obtained after the elimination of distortions. Furthermore, the positioning accuracy with relatively few ground control points is shown to be better than 1.5 pixels.