C-type arm image correction method based on perspective imaging model calibration

Abstract

A C-type arm image correction method based on perspective imaging model calibration comprises the following four steps: step 1, designing a calibration panel calibrated by a C-type arm system; step 2, obtaining distortion coordinates of marked points by image processing on distorted images; step 3, calibrating the C-type arm system, including system calibration of three dimensional coordinates of marked points on the calibration panel, perspective imaging models, distortion models and distortion coordinates to obtain perspective imaging parameters; step 4, correcting images, namely, the calibrated perspective imaging models are used for correcting the distorted images. In the method, the C-type arm system calibration and the C-type arm X-ray distorted projected image correction are considered as a whole on line, and the C-type arm system is calibrated and the C-type arm X-ray distorted projected image is corrected based on the perspective imaging model of the camera, thereby changing the traditional method that image correction is first carried out off line and then linear calibration is carried out and ensuring concise and convenient system steps an easy on-line use.

Description

(1) Technical field [0001] The invention relates to a C-arm image correction method based on perspective imaging model calibration, which mainly takes the C-arm system imaging parameter calibration and C-arm X-ray projection distortion image correction as a whole, and calibrates the C-arm based on the perspective imaging model. The C-arm system obtains the internal and external parameters of the C-arm system, and then utilizes the distortion parameters obtained by calibrating the C-arm system to realize an image correction method for distorted C-arm X-ray projection images, which belongs to the field of image processing. (2) Background technology [0002] Image correction is a common image processing method, such as image mosaic after remote sensing image correction, aerial image correction before use, camera image correction for positioning or three-dimensional reconstruction. [0003] At present, there are three types of distortions in C-arm X-ray projection images: pincus...

AI Technical Summary

Problems solved by technology

The advantage is that the calculation is simple, and the disadvantage is that the center of the calibration template, the center of the image intensifier and the radiation source are not on the same line due to the influence of the weight of the image intensifier and the calibration template in the C-arm system

If you continue to use the linear model to calibrate the C-arm system, the obtained C-arm system parameters will be inaccurate, which will seriously affect the navigation accuracy

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