opencv读取MATLAB双目标定的结果进行双目校正【图文】

概述：

opencv内部也有双目标定的函数，但是结果有时候会飘，所以想先用MATLAB标定工具箱试试看。使用MATLAB先队两个相机进行单目标定，然后进行双目标定，将结果保存在xml文件中。xml文件时opencv支持的文件格式，更详细的解释可以去搜索相关资料。

1.工具准备：

MATLAB标定工具箱。

这一步我认为应该单独强调一下。我的MATLAB版本是2014a，应用程序里面自带一个标定工具箱但是只支持单目。后来在​​http://www.vision.caltech.edu/bouguetj/calib_doc/#examples​​了解到应该再下载一个双目标定的工具箱。​​下载链接​​

将其解压到Matlab的工作目录下，然后将其包含到matlab的工作路径下。运行calib_gui就可以打开matlab标定工具箱主界面：

2.标定过程

1.点击Image names会出现当前MATLAB路径下的所有文件，如上图，输入L表示对L开头的图片进行标定，然后输入后缀b表示图片格式是bmp格式的。

2.点击Extract grid corners，检测角点，这个过程比较麻烦，一路回车下来，会依次弹出各张图片，需要用鼠标顺时针或逆时针选定最外层的角点。选择完第一张的时候会要求输入棋盘格的宽度，我的棋盘格长宽都是15mm。

之后就是对所有L开头的图片选取四个最外层角点，这一步完成后，点击Calibration进行标定，点击Save保存结果Calib_Result.mat，将Calib_Results.mat修改为Calib_Results_left.mat方便进行双目标定。

右相机同理。

3.双目标定

在MATLAB控制台输入stereo_gui，打开双目标定工具箱，点击Load left and right calibration files，再点击stereo calibration进行标定。得到如下结果：

3.保存为xml文件

Distortion_Camera_Left.xml

1. 
   
   <?xml version="1.0"?>
   
2. 
   
   <opencv_storage>
   
3. 
   
   <Distortion type_id="opencv-matrix">
   
4. 
   
   <rows>5 </rows>
   
5. 
   
   <cols>1 </cols>
   
6. 
   
   <dt>d </dt>
   
7. 
   
   <data>
   
8. 
   
   -0.15761 4.24565 -0.00236 0.02423 0.00000
   
9. 
   
   </data>
   
10. 
    
    </Distortion>
    
11. 
    
    </opencv_storage>
    

Distortion_Camera_Right.xml

1. 
   
   <?xml version="1.0"?>
   
2. 
   
   <opencv_storage>
   
3. 
   
   <Distortion type_id="opencv-matrix">
   
4. 
   
   <rows>5 </rows>
   
5. 
   
   <cols>1 </cols>
   
6. 
   
   <dt>d </dt>
   
7. 
   
   <data>
   
8. 
   
   -0.09281 1.60263 0.00408 -0.00825 0.00000
   
9. 
   
   </data>
   
10. 
    
    </Distortion>
    
11. 
    
    </opencv_storage>
    

Intrinsics_Camera_Left.xml

1. 
   
   <?xml version="1.0"?>
   
2. 
   
   <opencv_storage>
   
3. 
   
   <Intrinsics_Camera_Left type_id="opencv-matrix">
   
4. 
   
   <rows>3 </rows>
   
5. 
   
   <cols>3 </cols>
   
6. 
   
   <dt>d </dt>
   
7. 
   
   <data>
   
8. 
   
   2752.23366 0. 732.90263
   
9. 
   
   0. 2786.18468 529.17431
   
10. 
    
    0. 0. 1.
    
11. 
    
    </data>
    
12. 
    
    </Intrinsics_Camera_Left>
    
13. 
    
    </opencv_storage>
    

Intrinsics_Camera_Right.xml

1. 
   
   <?xml version="1.0"?>
   
2. 
   
   <opencv_storage>
   
3. 
   
   <Intrinsics_Camera_Right type_id="opencv-matrix">
   
4. 
   
   <rows>3 </rows>
   
5. 
   
   <cols>3 </cols>
   
6. 
   
   <dt>d </dt>
   
7. 
   
   <data>
   
8. 
   
   2667.95661 0. 584.91164
   
9. 
   
   0. 2699.92379 539.37941
   
10. 
    
    0. 0. 1.
    
11. 
    
    </data>
    
12. 
    
    </Intrinsics_Camera_Right>
    
13. 
    
    </opencv_storage>
    

RotRodrigues.xml

1. 
   
   <?xml version="1.0"?>
   
2. 
   
   <opencv_storage>
   
3. 
   
   <RotRodrigues type_id="opencv-matrix">
   
4. 
   
   <rows>3 </rows>
   
5. 
   
   <cols>1 </cols>
   
6. 
   
   <dt>d </dt>
   
7. 
   
   <data>
   
8. 
   
   0.02812 0.54890 0.00618
   
9. 
   
   </data>
   
10. 
    
    </RotRodrigues>
    
11. 
    
    </opencv_storage>
    

Translation.xml

1. 
   
   <?xml version="1.0"?>
   
2. 
   
   <opencv_storage>
   
3. 
   
   <Translation type_id="opencv-matrix">
   
4. 
   
   <rows>3 </rows>
   
5. 
   
   <cols>1 </cols>
   
6. 
   
   <dt>d </dt>
   
7. 
   
   <data>
   
8. 
   
   -160.89829 -1.36460 25.91248
   
9. 
   
   </data>
   
10. 
    
    </Translation>
    
11. 
    
    </opencv_storage>
    

4.opencv读取xml文件，并进行双目校正

1. 
   
   //读取内部参数
   
2. 
   
   CvMat *Intrinsics_Camera_Left = (CvMat *)cvLoad( "Intrinsics_Camera_Left.xml");
   
3. 
   
   CvMat *Intrinsics_Camera_Right = (CvMat *)cvLoad( "Intrinsics_Camera_Right.xml");
   
4. 
   
   CvMat *Distortion_Camera_Left = (CvMat *)cvLoad( "Distortion_Camera_Left.xml");
   
5. 
   
   CvMat *Distortion_Camera_Right = (CvMat *)cvLoad( "Distortion_Camera_Right.xml");
   
6. 
   
   CvMat *Translation_matlab = (CvMat *)cvLoad( "Translation.xml");
   
7. 
   
   CvMat *RotRodrigues_matlab = (CvMat *)cvLoad( "RotRodrigues.xml");
   
8. 
   
   CvMat *R_opencv = cvCreateMat( 3, 3, CV_64F);
   
9. 
   
   cvRodrigues2(RotRodrigues_matlab, R_opencv);
   
10. 
    
    //创建映射矩阵
    
11. 
    
    IplImage *Left_Mapx = cvCreateImage(cvSize( 1280, 960), IPL_DEPTH_32F, 1);
    
12. 
    
    IplImage *Left_Mapy = cvCreateImage(cvSize( 1280, 960), IPL_DEPTH_32F, 1);
    
13. 
    
    IplImage *Right_Mapx = cvCreateImage(cvSize( 1280, 960), IPL_DEPTH_32F, 1);
    
14. 
    
    IplImage *Right_Mapy = cvCreateImage(cvSize( 1280, 960), IPL_DEPTH_32F, 1);
    
15. 
    
    CvMat *Rl = cvCreateMat( 3, 3, CV_64F);
    
16. 
    
    CvMat *Rr = cvCreateMat( 3, 3, CV_64F);
    
17. 
    
    CvMat *Pl = cvCreateMat( 3, 4, CV_64F);
    
18. 
    
    CvMat *Pr = cvCreateMat( 3, 4, CV_64F);
    
19. 
    
    //双目校正
    
20. 
    
    cvStereoRectify(Intrinsics_Camera_Left, Intrinsics_Camera_Right,
    
21. 
    
    Distortion_Camera_Left, Distortion_Camera_Right,
    
22. 
    
    cvSize( 1280, 960), R_opencv, Translation_matlab,
    
23. 
    
    Rl, Rr, Pl, Pr, 0, 2048, 0); //增加图像缩放，去除死区
    
24. 
    
    //畸变矫正
    
25. 
    
    cvInitUndistortRectifyMap(Intrinsics_Camera_Left, Distortion_Camera_Left, Rl, Pl,
    
26. 
    
    Left_Mapx, Left_Mapy);
    
27. 
    
    cvInitUndistortRectifyMap(Intrinsics_Camera_Right, Distortion_Camera_Right, Rr, Pr,
    
28. 
    
    Right_Mapx, Right_Mapy);
    

1. 
   
   cvRemap(IplimgLeft, img_left_Change, Left_Mapx, Left_Mapy);
   
2. 
   
   cvRemap(IplimgRight, img_right_Change, Right_Mapx, Right_Mapy);
   
3. 
   
   
   
4. 
   
   cvLine(img_left_Change, cvPoint( 0, 96 * 1), cvPoint( 1280 - 1, 96), cvScalar( 255, 0, 0));
   
5. 
   
   
   
6. 
   
   cvLine(img_left_Change, cvPoint( 0, 96 * 2), cvPoint( 1280 - 1, 96 * 2), cvScalar( 255, 0, 0));
   
7. 
   
   cvLine(img_left_Change, cvPoint( 0, 96 * 3), cvPoint( 1280 - 1, 96 * 3), cvScalar( 255, 0, 0));
   
8. 
   
   cvLine(img_left_Change, cvPoint( 0, 96 * 4), cvPoint( 1280 - 1, 96 * 4), cvScalar( 255, 0, 0));
   
9. 
   
   cvLine(img_left_Change, cvPoint( 0, 96 * 5), cvPoint( 1280 - 1, 96 * 5), cvScalar( 255, 0, 0));
   
10. 
    
    cvLine(img_left_Change, cvPoint( 0, 96 * 6), cvPoint( 1280 - 1, 96 * 6), cvScalar( 255, 0, 0));
    
11. 
    
    cvLine(img_left_Change, cvPoint( 0, 96 * 7), cvPoint( 1280 - 1, 96 * 7), cvScalar( 255, 0, 0));
    
12. 
    
    cvLine(img_left_Change, cvPoint( 0, 96 * 8), cvPoint( 1280 - 1, 96 * 8), cvScalar( 255, 0, 0));
    
13. 
    
    cvLine(img_left_Change, cvPoint( 0, 96 * 9), cvPoint( 1280 - 1, 96 * 9), cvScalar( 255, 0, 0));
    
14. 
    
    cvLine(img_right_Change, cvPoint( 0, 96 * 1), cvPoint( 1280 - 1, 96), cvScalar( 255, 0, 0));
    
15. 
    
    cvLine(img_right_Change, cvPoint( 0, 96 * 2), cvPoint( 1280 - 1, 96 * 2), cvScalar( 255, 0, 0));
    
16. 
    
    cvLine(img_right_Change, cvPoint( 0, 96 * 3), cvPoint( 1280 - 1, 96 * 3), cvScalar( 255, 0, 0));
    
17. 
    
    cvLine(img_right_Change, cvPoint( 0, 96 * 4), cvPoint( 1280 - 1, 96 * 4), cvScalar( 255, 0, 0));
    
18. 
    
    cvLine(img_right_Change, cvPoint( 0, 96 * 5), cvPoint( 1280 - 1, 96 * 5), cvScalar( 255, 0, 0));
    
19. 
    
    cvLine(img_right_Change, cvPoint( 0, 96 * 6), cvPoint( 1280 - 1, 96 * 6), cvScalar( 255, 0, 0));
    
20. 
    
    cvLine(img_right_Change, cvPoint( 0, 96 * 7), cvPoint( 1280 - 1, 96 * 7), cvScalar( 255, 0, 0));
    
21. 
    
    cvLine(img_right_Change, cvPoint( 0, 96 * 8), cvPoint( 1280 - 1, 96 * 8), cvScalar( 255, 0, 0));
    
22. 
    
    cvLine(img_right_Change, cvPoint( 0, 96 * 9), cvPoint( 1280 - 1, 96 * 9), cvScalar( 255, 0, 0));
    

6.效果

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