Calibration method of on-orbit optical distortion parameters of linear array push-broom camera

Abstract

The invention discloses a calibration method of on-orbit optical distortion parameters of a linear array push-broom camera. The method comprises the following steps: firstly, collecting and obtaining dense high precision control point information by adopting an automatch algorithm based on control points, secondly, establishing strict imaging geometric models of all the control points, thirdly, computing the theoretical steering vector and the practical steering vector of each control point, and establishing an internal orientation element geometric calibration mathematical model of the camera, fourthly, establishing a distortion polynomial model, in which the theoretical steering vectors correspond to image column numbers, and fifthly, solving an error equation through a least square method, and performing iteration solving, so as to obtain internal optical distortion calibration parameters of the camera. The method calibrates internal optical system distortion of the satellite on-orbit camera by selecting a large number of high-precision ground control points, calibration results can be used for improving the uncontrolled positioning precision and the controlled positioning precision of satellite images, after internal orientation elements of the camera are corrected through internal distortion parameters, internal distortion of the images is basically eliminated.

Description

technical field [0001] The invention relates to a calibration method for on-orbit optical distortion parameters of a linear array push-broom camera, which belongs to the technical field of remote sensing satellite image processing and is used for optimizing and improving the on-orbit positioning accuracy of a linear push-broom camera mounted on a remote sensing satellite and improving the internal geometric quality of the image improvement optimization. Background technique [0002] With the continuous development of space technology, satellite remote sensing imagery has become an important data source for current geospatial information services and applications, and its wide application prospects have attracted widespread attention from all over the world. Compared with the ability to obtain high-resolution satellite data a few years ago, countries around the world have been scrambling to develop their own high-resolution earth observation systems in recent years, and the s...

AI Technical Summary

Problems solved by technology

Although the geometric positioning accuracy of domestic satellites is gradually improving, compared with foreign commercial high-resolution optical remote sensing satellites such as Geoeye, WorldView, Pleiades, etc., there is still a big gap in the geometric positioning accuracy of domestic satellites, especially the internal geometric accuracy of images. It cannot meet the production requirements of orthophoto products in the fields of land resources, surveying and mapping, etc., which seriously restricts the application performance of high-resolution satellite images in my country

[0004] Affected by launch momentum, on-orbit environment and other factors, the internal geometric distortion parameters of the aerospace remote sensing optical camera have changed greatly after the orbit, and the internal parameters of the camera measured on the ground will lead to large internal distortion when used for image geometric processing. Distortion, especially the internal distortion of images far away from the main point can reach the order of 30 meters, which seriously restricts the improvement of its positioning accuracy and affects subsequent advanced applications such as image mosaic mosaic

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