借助Matlab标定

Matlab APP
在MATLAB的APP中找到Stereo Camrea Calibrator,打开。
图片路径
点击Add Images，选择双目照片，camera1和camera2的存放路径必须分开。每个棋盘格的长度是25mm（我是采用的OpenCV官方的标定图纸，9*6，每个格子是标准的25mm）
标定脚本
点击确定，导入图像成功后，点击Calibrate，开始标定。标定结束后点击Show Rectified可以显示矫正图。
Matlab矫正视图
成功生成矫正图，但是我们发现有一组差距明显过大，可以在柱状图的长条上面选中误差最大的一组，按delete键删除，将自动重新生成新的矫正参数和矫正图。
撇去误差
可以选择Export Camera Parameters到出双目参数或MATLAB标定脚本，单独运行标定脚本会得到如下的标定结果输出：

Matlab标定结果

Standard Errors of Estimated Stereo Camera Parameters
            -----------------------------------------------------

Camera 1 Intrinsics  //相机1内参
-------------------
Focal length (pixels):   [  452.8131 +/- 3.8144      452.8235 +/- 3.8139  ]
Principal point (pixels):[  303.0163 +/- 1.0834      228.0770 +/- 0.6888  ]
Radial distortion:       [   -0.0241 +/- 0.0168        0.4826 +/- 0.1491  ]

Camera 1 Extrinsics  //相机1外参
-------------------
Rotation vectors:    //外参旋转矩阵
                         [   -0.0851 +/- 0.0021       -0.2526 +/- 0.0028        1.2113 +/- 0.0004  ]
                         [   -0.0063 +/- 0.0039       -0.2043 +/- 0.0036       -0.4643 +/- 0.0005  ]
                         [    0.1201 +/- 0.0033       -0.2520 +/- 0.0033       -0.7513 +/- 0.0006  ]
                         [    0.2224 +/- 0.0035       -0.2507 +/- 0.0032       -1.5631 +/- 0.0006  ]
                         [    0.4167 +/- 0.0037       -0.2458 +/- 0.0029       -2.1221 +/- 0.0007  ]
                         [   -0.1193 +/- 0.0026       -0.4083 +/- 0.0029       -0.1314 +/- 0.0006  ]
                         [    0.0427 +/- 0.0036       -0.2686 +/- 0.0035       -0.0184 +/- 0.0005  ]
                         [    0.0529 +/- 0.0021       -0.2863 +/- 0.0027        0.0821 +/- 0.0004  ]
                         [    0.0338 +/- 0.0022       -0.0208 +/- 0.0017        0.0326 +/- 0.0003  ]
                         [    0.0824 +/- 0.0019        0.0539 +/- 0.0017       -0.5268 +/- 0.0003  ]
                         [    0.0899 +/- 0.0020        0.0557 +/- 0.0018       -0.8509 +/- 0.0003  ]
                         [    0.1354 +/- 0.0022        0.0859 +/- 0.0019       -1.2999 +/- 0.0004  ]
                         [    0.1641 +/- 0.0022        0.0955 +/- 0.0019       -1.4819 +/- 0.0004  ]
                         [   -0.0260 +/- 0.0039       -0.1834 +/- 0.0037       -0.0204 +/- 0.0005  ]

Translation vectors (millimeters):  //外参平移矩阵
                         [   20.4809 +/- 0.9833     -119.1858 +/- 0.6280      412.9415 +/- 3.4706  ]
                         [  -56.4057 +/- 1.8157      -19.9519 +/- 1.1488      754.6843 +/- 6.3684  ]
                         [  -49.6146 +/- 1.7748       31.7953 +/- 1.1268      738.4469 +/- 6.2787  ]
                         [   14.8648 +/- 1.7827      128.2739 +/- 1.1357      744.9940 +/- 6.3494  ]
                         [   96.5079 +/- 1.8262      160.2178 +/- 1.1637      766.2099 +/- 6.4916  ]
                         [  -68.2884 +/- 1.6775      -47.8024 +/- 1.0592      697.6522 +/- 5.9128  ]
                         [  -81.0138 +/- 1.7026      -50.3143 +/- 1.0771      707.6428 +/- 5.9961  ]
                         [ -105.4409 +/- 0.9096      -74.2982 +/- 0.5760      376.4898 +/- 3.1783  ]
                         [ -104.7996 +/- 1.0105      -62.6256 +/- 0.6406      420.0483 +/- 3.5660  ]
                         [ -140.0403 +/- 0.9986        4.3986 +/- 0.6411      423.0394 +/- 3.5417  ]
                         [ -134.8034 +/- 1.0358       52.9123 +/- 0.6590      437.2303 +/- 3.6528  ]
                         [  -95.4044 +/- 1.0746      107.3640 +/- 0.6767      452.7615 +/- 3.7488  ]
                         [  -81.0545 +/- 1.0732      126.3488 +/- 0.6716      451.4306 +/- 3.7314  ]
                         [  -30.1682 +/- 1.8434      -66.5197 +/- 1.1667      767.4144 +/- 6.4651  ]

Camera 2 Intrinsics  //相机2内参
-------------------
Focal length (pixels):   [  453.6927 +/- 3.8129      453.9168 +/- 3.8269  ]
Principal point (pixels):[  311.4093 +/- 1.4798      237.1017 +/- 0.6553  ]
Radial distortion:       [    0.0171 +/- 0.0078       -0.0338 +/- 0.0208  ]
//相机2相对于相机1的位置和方向
Position And Orientation of Camera 2 Relative to Camera 1
---------------------------------------------------------
Rotation of camera 2:         [    0.0076 +/- 0.0012       -0.0140 +/- 0.0024       -0.0024 +/- 0.0002  ]
Translation of camera 2 (millimeters):[  -70.2056 +/- 0.0697        0.1296 +/- 0.0516        0.6029 +/- 0.4883  ]

向OpenCV中写入标定结果并测试。参见双目测距（四）