A New Method for Liner Pushbroom Imagery Exterior Orientation
WANGTao, ZHANG Yan, XU Qing, TAN Bing, XING Shuai
(Institute of Surveying and Mapping, Information Engineering University, Zhengzhou 450052, China)
Abstract£ºThe strong interrelationship among exterior elements of linear pushbroom imagery induces normal equation severely ill-posed and least squares value deviated from the true value. In this paper the Ridge-Stein combined estimator (RSC) is presented for linear pushbroom imagery exterior orientation. The estimator is a new biased method combining the Ridge estimator and the Stein estimator. It achieves optimum estimation values through applying different scale compression to each least squares component. In the paper we make experiments with one 10-meter SPOT 1 panchromatic image and one 2.5-meter SPOT 5 panchromatic image, and compare the results with values computed using commercial remote-sensing software Erdas. The research results show that the algorithm can effectively overcome the strong interrelationship among exterior elements and achieve high accuracy. The position precision can be within one pixel for orientation points and within one and a half pixels for check points, as accurate as that of Erdas software.
Key words£ºlinear pushbroom imagery£» exterior orientation£» least squares estimator£» Ridge estimator£» Stein estimator£» Ridge-Stein combined estimator