Parameter calibration method and parameter calibration device

Abstract

The invention relates to a parameter calibration method. The method comprises steps as follows: controlling image acquisition equipment to perform shooting in an ith pose to obtain an X-ray image, andcontrolling a mechanical arm to move to realize that the X-ray image shot by the image acquisition equipment contains at least the preset number of metal balls in multiple metal balls; recording ithpose information of the mechanical arm; determining two-dimensional coordinates of the metal balls in the X-ray image and an ith transformation matrix of three-dimensional coordinates of the metal balls in a coordinate system at the tail end of the mechanical arm; and determining a geometric position relation of a world coordinate system and the coordinate system where the X-ray image is located according to the ith transformation matrix and the ith pose information. According to the parameter calibration method, the process of determining the geometric position relation of the world coordinate system and the coordinate system where the X-ray image is located does not need a specific die body, the process is relatively simple, and besides, the pose information of the mechanical arm is relatively accurate and easy to determine, so that a result with higher accuracy can be obtained through the relatively simple process.

Description

technical field [0001] The present disclosure relates to the field of medical technology, and in particular to a parameter calibration method, a parameter calibration device, electronic equipment, and a computer-readable storage medium. Background technique [0002] CBCT (Cone Beam Computed tomography, cone beam projection computerized tomography), CBCT is to collect multiple perspective images within a 360-degree range around the imaging object, and then use a reconstruction algorithm to obtain a three-dimensional CT image. That is, geometric parameters of different perspective perspectives need to be obtained before 3D CT image reconstruction, so as to calculate the geometric positional relationship between the world coordinate system and each image. [0003] Algorithms in related technologies, using such as figure 1 As shown in the phantom, the phantom is a cylindrical structure, and two layers of steel balls are evenly arranged on the cylinder. The phantom is placed in ...

AI Technical Summary

Problems solved by technology

[0004] Since the steel balls arranged in a circle are arranged in an ellipse in the perspective image, too few steel balls will affect the accuracy of ellipse fitting, and too many steel balls will overlap in the perspective image and cause it to be unrecognizable

And using ellipse parameters to calculate the transformation relationship is an indirect way, and the calculation is relatively complicated and the accuracy is relatively low

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