An Image Block Adjustment Method Constrained by Global Digital Elevation Model

Abstract

The invention discloses an image area network adjustment method constrained by a global digital elevation model. Firstly, a three-dimensional image adjustment area network is constructed and dense connection points are arranged. Then obtain the global digital elevation model data in the survey area, divide the survey area into three types of terrain areas: flat land, hills and mountains, and set the elevation values ​​corresponding to ground points in different terrain areas obtained by using the global digital elevation model data for adjustment calculations Constraint rules for the correction number; finally carry out block network adjustment calculation, use this constraint rule to constrain the elevation value correction number of the connection point corresponding to the ground point in each iterative calculation, until the end of the adjustment, and according to the adjustment result as A new imaging geometry model parameter file is generated for each image. The invention implements elevation constraints on regional network adjustments by adopting different rules in different terrain areas and using global digital elevation models, so as to realize a substantial improvement in the elevation accuracy of satellite remote sensing images under the condition of no ground control.

Description

technical field

[0001] The invention relates to the technical field of photogrammetry, in particular to an image block adjustment method constrained by a global digital elevation model. Background technique

[0002] The digital elevation model is a solid ground model that expresses the ground elevation in the form of a set of ordered numerical arrays. At present, the global digital elevation model products that can be obtained free of charge through the Internet mainly include: ① SRTM-DEM (full name Space Shuttle Radar Topography Mission): produced by NASA and others and provided free of charge, its data coverage ranges from 60° north latitude to All land areas between 56° south latitude account for 80% of the earth's land surface. The world's highest resolution is 30 meters, and the official nominal elevation has an error of 10 meters. ②ASTER GDEM (full name Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model): It is jointly produc...

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