caltab_points ( : : CalTabDescrFile : X, Y, Z )

Read the mark center points from the calibration table description file.

caltab_points is used to read the mark center points from the calibration table description file CalTabDescrFile. The mark center points are 3D coodinates in the calibration table coordinate system und describe the 3D model of the calibration table. The application of the operator camera_calibration projects these model points into the image. By minimizing the distance between the projected model points and the observed 2D coordinates in the image (see find_marks_and_pose) the exact values for the internal and external camera parameters are computed.


Parameters

CalTabDescrFile (input_control)
string -> string
File name of the calibration table description.
Default value: 'caltab.descr'

X (output_control)
real-array -> real
X-coordinates of the mark center points.

Y (output_control)
real-array -> real
Y-coordinates of the mark center points.

Z (output_control)
real-array -> real
Z-coordinates of the mark center points.


Example
/* read_image(:Image1:'calib-01.tiff':) >
/* find calibration pattern */
find_caltab(Image1:Caltab1:'caltab.descr',3,112:) >
/* find calibration marks and start poses */
find_marks_and_pose(Image1,Caltab1::'caltab.descr',[0.008,0.0,
  0.000011,0.000011,384,288,768,576],128,10:RCoord1,CCoord1,StartPose1) >
/* read 3D positions of calibration marks */
caltab_points(::'caltab.descr':NX,NY,NZ) >
/* camera calibration */
camera_calibration(::NX,NY,NZ,RCoord1,CCoord1,
  [0.008,0.0,0.000011,0.000011,384,288,768,576],
  StartPose1,11:CamParam,FinalPose,Errors) >
/* visualize calibration result */
disp_image(Image1:::) >
set_color(::'red':) >
disp_caltab(::'caltab.descr',CamParam,FinalPose,1.0:).

Result

caltab_points returns TRUE if all parameter values are correct and the file CalTabDescrFile has been read successfully. If necessary an exception is raised.


Possible Successors

camera_calibration


See also

find_caltab, find_marks_and_pose, camera_calibration, disp_caltab, sim_caltab, project_3d_point, inverse_project_pixel, create_caltab



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