stereoCalibrationErrors class

Object for storing standard errors of estimated stereo parameters

Syntax

stereoCalibrationErrors

Description

stereoCalibrationErrors contains the standard errors of estimated stereo parameters. The estimateCameraParameters function returns the stereoCalibrationErrors object. You can access the standard errors for stereo calibration using the object’s properties. You can display the standard errors using the object displayErrors method.

Properties

Camera1IntrinsicsErrors

Standard errors of camera 1 estimated intrinsics and distortion coefficients, specified as an intrinsicsEstimationErrors object.

Camera1ExtrinsicsErrors

Standard errors of camera 1 estimated extrinsics parameters, specified as an extrinsicsEstimationErrors object.

Camera2IntrinsicsErrors

Standard errors of camera 2 estimated intrinsics and distortion coefficients, specified as an intrinsicsEstimationErrors object.

RotationOfCamera2Error

Standard errors of rotated vector of camera 2 relative to camera 1, specified as a 3-element vector.

TranslationOfCamera2Error

Standard errors of translation of camera 2 relative to camera 1, specified as a 3-element vector.

Methods

displayErrorsDisplay standard errors of camera parameter estimation

Examples

collapse all

Specify calibration images.

imageDir = fullfile(toolboxdir('vision'), 'visiondata', ...
  'calibration','stereo');
leftImages = imageDatastore(fullfile(imageDir,'left'));
rightImages = imageDatastore(fullfile(imageDir,'right'));

Detect the checkerboards.

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

Specify world coordinates of checkerboard keypoints. Square size is in millimeters.

squareSize = 108;
worldPoints = generateCheckerboardPoints(boardSize,squareSize);

Calibrate the stereo camera system. Here both cameras have the same resolution.

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

Display standard errors.

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

Camera 1 Intrinsics
-------------------
Focal length (pixels):   [ 1038.0286 +/- 0.6533     1037.9145 +/- 0.6389  ]
Principal point (pixels):[  656.0841 +/- 0.3408      485.5485 +/- 0.2639  ]
Radial distortion:       [   -0.3617 +/- 0.0008        0.1866 +/- 0.0026  ]

Camera 1 Extrinsics
-------------------
Rotation vectors:
                         [    0.1680 +/- 0.0007       -0.0271 +/- 0.0006        3.1125 +/- 0.0001  ]
                         [    0.1995 +/- 0.0006       -0.0523 +/- 0.0005       -3.0991 +/- 0.0000  ]
                         [    0.4187 +/- 0.0005       -0.1061 +/- 0.0004       -3.1113 +/- 0.0001  ]
                         [    0.5239 +/- 0.0005       -0.0604 +/- 0.0004       -3.0552 +/- 0.0001  ]
                         [    0.6807 +/- 0.0006       -0.0306 +/- 0.0005       -3.0331 +/- 0.0001  ]
                         [    0.3513 +/- 0.0007       -0.0993 +/- 0.0006       -3.0334 +/- 0.0001  ]
                         [    0.0212 +/- 0.0007       -0.1179 +/- 0.0007       -3.0833 +/- 0.0000  ]
                         [   -0.2765 +/- 0.0008       -0.0847 +/- 0.0007       -3.0943 +/- 0.0001  ]
                         [   -0.4407 +/- 0.0007       -0.1119 +/- 0.0006       -3.0652 +/- 0.0001  ]
                         [   -0.2537 +/- 0.0008       -0.1334 +/- 0.0007       -3.1039 +/- 0.0001  ]

Translation vectors (mm):
                         [  708.4192 +/- 0.4914      227.0500 +/- 0.4002     1492.8672 +/- 1.0127  ]
                         [  368.4408 +/- 0.5228      191.7200 +/- 0.4094     1589.9146 +/- 0.9987  ]
                         [  226.3710 +/- 0.5173      191.1429 +/- 0.4030     1578.4779 +/- 0.9576  ]
                         [   49.5377 +/- 0.5183      196.7495 +/- 0.4030     1580.5404 +/- 0.9493  ]
                         [ -172.4001 +/- 0.7003      150.9910 +/- 0.5406     2119.3253 +/- 1.2532  ]
                         [   10.7777 +/- 0.6784      176.8785 +/- 0.5276     2066.8343 +/- 1.2907  ]
                         [  295.4840 +/- 0.6616      167.8675 +/- 0.5158     2010.7713 +/- 1.2738  ]
                         [  614.2338 +/- 0.6457      166.2016 +/- 0.5153     1968.1798 +/- 1.2722  ]
                         [  767.0156 +/- 0.6106      165.5372 +/- 0.4991     1868.3334 +/- 1.2395  ]
                         [  953.8133 +/- 0.7336      -14.7981 +/- 0.6039     2255.6170 +/- 1.5107  ]

Camera 2 Intrinsics
-------------------
Focal length (pixels):   [ 1042.4817 +/- 0.6644     1042.2692 +/- 0.6534  ]
Principal point (pixels):[  640.5972 +/- 0.3305      479.0652 +/- 0.2633  ]
Radial distortion:       [   -0.3614 +/- 0.0007        0.1822 +/- 0.0022  ]

Position And Orientation of Camera 2 Relative to Camera 1
---------------------------------------------------------
Rotation of camera 2:         [   -0.0037 +/- 0.0002        0.0050 +/- 0.0004       -0.0002 +/- 0.0000  ]
Translation of camera 2 (mm): [ -119.8720 +/- 0.0401       -0.4005 +/- 0.0414       -0.0258 +/- 0.1750  ]
Introduced in R2014b