基于成像光线空间追踪的摄像机标定方法研究

Research on camera calibration method based on imaging ray tracking

摄像机测量模型和标定方法是视觉测量的关键,直接影响视觉测量系统的测量精度。针对这个问题,借鉴非成像模型的摄像机校准的思想,提出了基于成像光线追踪的摄像机标定方法。分析测量点经摄像机镜头成像的规律,通过空间直线确定摄像机图像坐标与测量空间的映射关系。使用像平面和两个空间平面的映射关系,建立空间直线表达方式,完成基于成像追踪方法的摄像机测量参数标定。通过噪声分析和精度测量实验对基于成像追踪的摄像机标定方法进行精度验证,实验结果表明该方法可以有效抑制标定数据噪声对测量结果的影响,提高摄像机标定精度。

Camera measurement model and calibration method are the keys in computer vision,which influences the measurement accuracy of the measurement system directly. Aiming at this issue,a camera calibration method based on imaging ray tracking is proposed according to the nonparametric model calibration method. The imaging law of the measurement point through camera is analyzed; and the mapping relationship between the image coordinate of the camera and the three-dimensional coordinate is established with a spatial line.The expression of the spatial line is established with the mapping relationship between the image plane and two spatial planes. The measurement parameters of the camera are calibrated based on the imaging ray tracking method. Both noise analysis and accuracy evaluation experiments were used to verify the calibration method based on imaging ray tracking. Experiment result shows that the proposed method can effectively reduce the influence of the calibration data noise on measurement result and improve the camera calibration precision.