基于MATLAB的摄像机的标定与实现

Calibration and Implementation of MATLAB Based Camera

摄像机标定的目的是建立二维图像坐标与三维空间坐标之间的关系,利用摄像机从不同角度拍摄到的照片,通过一系列数学过程得到物体三维坐标值。首先建立摄像机的针孔成像模型,从与摄像机标定有关的几个坐标系出发推导了在针孔模型下图像坐标到世界坐标的转化以及摄像机的投影矩阵的表达形式,利用Harris角点检测算法提取了待定标图像的特征点;最后结合MATLAB工具箱利用直接线性变换的方法求解了摄像机的内外参数,并给出了参数的像素误差,结果较为准确。

Camera calibration aims to establish the relationship between 2D image coordinate and 3D space coordinate, then by a series calculation obtain the object＇s 3D coordinate values with photos taken from different angles. This paper first builds up a pinhole imaging model. Considering a number of camera calibration concerned coordinate systems, it then deduces the transformation from image coordinate to world coordinate under this model and the expression of the projection matrix, and extracts the feature point of the under-calibration picture with the Harris tracer. Finally, it works out the camera＇s internal and external parameters as well as the pixel error of the parameters with the MATLAB toolbox. The results prove accurate.