cameraCalibrationErrors

Object for storing standard errors of estimated camera parameters

Description

cameraCalibrationErrors contains the standard errors of estimated camera parameters. The estimateCameraParameters function returns the cameraCalibrationErrors object. You can access the intrinsics and extrinsics standard errors using the object properties. You can display the standard errors using the object’s displayErrors method.

Properties

expand all

Standard error of the estimated intrinsics for a camera, specified as a intrinsicsEstimationErrors object.

Standard error of the estimate rotations and translations for a camera relative to the calibration pattern, specified as a extrinsicsEstimationErrors object.

Object Functions

displayErrorsDisplay standard errors of camera parameter estimates

Examples

collapse all

Create a set of calibration images.

images = imageDatastore(fullfile(toolboxdir('vision'),'visiondata', ...
 'calibration','mono'));

Detect the calibration pattern.

[imagePoints,boardSize] = detectCheckerboardPoints(images.Files);

Generate the world coordinates of the corners of the squares. The units of the square are in millimeters.

squareSize = 29;
worldPoints = generateCheckerboardPoints(boardSize,squareSize);

Calibrate the camera.

I = readimage(images,1); 
imageSize = [size(I,1),size(I,2)];
[params,~,errors] = estimateCameraParameters(imagePoints,worldPoints, ...
                                  'ImageSize',imageSize);

Display the standard errors.

displayErrors(errors,params);
			Standard Errors of Estimated Camera Parameters
			----------------------------------------------

Intrinsics
----------
Focal length (pixels):   [  714.1886 +/- 3.3219      710.3786 +/- 4.0579  ]
Principal point (pixels):[  563.6480 +/- 5.3967      355.7251 +/- 3.3036  ]
Radial distortion:       [   -0.3536 +/- 0.0091        0.1730 +/- 0.0488  ]

Extrinsics
----------
Rotation vectors:
                         [   -0.6096 +/- 0.0054       -0.1789 +/- 0.0073       -0.3835 +/- 0.0024  ]
                         [   -0.7283 +/- 0.0050       -0.0996 +/- 0.0072        0.1964 +/- 0.0027  ]
                         [   -0.6722 +/- 0.0051       -0.1444 +/- 0.0074       -0.1329 +/- 0.0026  ]
                         [   -0.5836 +/- 0.0056       -0.2901 +/- 0.0074       -0.5622 +/- 0.0025  ]
                         [   -0.3157 +/- 0.0065       -0.1441 +/- 0.0075       -0.1067 +/- 0.0011  ]
                         [   -0.7581 +/- 0.0052        0.1947 +/- 0.0072        0.4324 +/- 0.0030  ]
                         [   -0.7515 +/- 0.0051        0.0767 +/- 0.0072        0.2070 +/- 0.0029  ]
                         [   -0.6223 +/- 0.0053        0.0231 +/- 0.0073        0.3663 +/- 0.0024  ]
                         [    0.3443 +/- 0.0063       -0.2226 +/- 0.0073       -0.0437 +/- 0.0014  ]

Translation vectors (mm):
                         [ -146.0516 +/- 6.0391      -26.8684 +/- 3.7318      797.9027 +/- 3.9002  ]
                         [ -209.4357 +/- 6.9637      -59.4563 +/- 4.3578      921.8198 +/- 4.6295  ]
                         [ -129.3823 +/- 7.0907      -44.1028 +/- 4.3751      937.6832 +/- 4.4913  ]
                         [ -151.0048 +/- 6.6905      -27.3251 +/- 4.1339      884.2789 +/- 4.3925  ]
                         [ -174.9499 +/- 6.7056      -24.3498 +/- 4.1606      886.4961 +/- 4.6686  ]
                         [ -134.3095 +/- 7.8887     -103.4979 +/- 4.8925     1042.4554 +/- 4.8184  ]
                         [ -173.9845 +/- 7.6891      -73.1689 +/- 4.7812     1017.2386 +/- 4.8126  ]
                         [ -202.9446 +/- 7.4327      -87.9089 +/- 4.6482      983.6958 +/- 4.9072  ]
                         [ -319.8860 +/- 6.3213     -119.8897 +/- 4.0922      829.4582 +/- 4.9591  ]

Introduced in R2014b