Precise calibration method of digital camera projection center position based on photogrammetry technology

Abstract

The invention relates to a digital camera projection center position precision calibration method based on a photogrammetric technology, and aims at effectively solving the problems of high precision and operability. The method comprises the steps that a return light reflection measurement mark, a control point mark, an encoding mark, a directional target and a standard ruler are laid to form a calibration field; an electronic theodolite and a to-be-inspected camera are arranged at the position 3 meters away from the calibration field, and the return light reflection measurement mark is stuck to a camera lens; the calibration field is photographed by the camera at the different horizontal positions to obtain multiple photos, the calibration field is photographed by the to-be-inspected camera at the different positions in front of the calibration field at different attitudes, and data of the control point mark are extracted from the photos to form calibration data; the coordinates of a central image point of the control point mark are corrected and resolved to obtain three projection center positions. According to the method, control point mark image center measurement, high-precision camera calibration and projection center precision measurement can be integrally achieved, and the calibration precision of the projection center positions is higher than 5 mm.

Description

technical field [0001] The invention relates to the field of camera imaging, in particular to a method for accurately marking the projection center position of a digital camera based on photogrammetry technology. Background technique [0002] In the research and application of photogrammetry, the imaging relationship of geometric optics has laid the theoretical foundation of analytical photogrammetry optics. The ideal optical system attributes the photographed film to the central projection of the photographed object, which is essentially the theory of "three collinear points", that is The image point, the projection center and the corresponding object point are located on the same straight line, based on which a whole set of analytical relations of conventional photogrammetry is established. [0003] The purpose of close-range photogrammetry is to use control points to inversely calculate the spatial coordinates of external points, and does not care about the specific locat...

AI Technical Summary

Problems solved by technology

The interferometric comparison measurement method needs to rely on precision optical instruments, has high requirements on equipment and environment, the implementation process is complicated, and it has high requirements on the site

The conventional method of estimating the projection center position based on the image sensor position and focal length has poor accuracy

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