| Operators |
create_caltab — Generate a calibration plate description file and a corresponding PostScript file. (obsolete)
create_caltab( : : Width, CalTabDescrFile, CalTabFile : )
create_caltab has been replaced with the operator gen_caltab. The operator is contained and described for compatibility reasons only.
create_caltab generates the description of a standard calibration plate for HALCON. This calibration plate consists of 49 black circular marks on a white plane which are surrounded by a black frame. The parameter Width sets the width (equal to the height) of the whole calibration plate in meters. Using a width of 0.8 m, the distance between two neighboring marks becomes 10 cm, and the mark radius and the frame width are set to 2.5 cm. The calibration plate coordinate system is located in the middle of the surface of the calibration plate, its z-axis points into the calibration plate, its x-axis to the right, and it y-axis downwards.
The file CalTabDescrFile contains the calibration plate description, e.g., the number of rows and columns of the calibration plate, the geometry of the surrounding frame (see find_caltab), and the coordinates and the radius of all calibration plate marks given in the calibration plate coordinate system. A file generated by create_caltab looks like the following (comments are marked by a '#' at the beginning of a line):
# # Description of the standard calibration plate # used for the camera calibration in HALCON # # 7 rows x 7 columns # Distance between mark centers [meter]: 0.1 # Number of marks per row r 7 # Number of marks per column c 7 # Quadratic frame (with outer and inner border) around calibration plate w 0.025 o -0.41 0.41 0.41 -0.41 i -0.4 0.4 0.4 -0.4 # calibration marks: x y radius [Meter] # calibration marks at y = -0.3 m -0.3 -0.3 0.025 -0.2 -0.3 0.025 -0.1 -0.3 0.025 0 -0.3 0.025 0.1 -0.3 0.025 0.2 -0.3 0.025 0.3 -0.3 0.025 # calibration marks at y = -0.2 m -0.3 -0.2 0.025 -0.2 -0.2 0.025 -0.1 -0.2 0.025 0 -0.2 0.025 0.1 -0.2 0.025 0.2 -0.2 0.025 0.3 -0.2 0.025 # calibration marks at y = -0.1 m -0.3 -0.1 0.025 -0.2 -0.1 0.025 -0.1 -0.1 0.025 0 -0.1 0.025 0.1 -0.1 0.025 0.2 -0.1 0.025 0.3 -0.1 0.025 # calibration marks at y = 0 m -0.3 0 0.025 -0.2 0 0.025 -0.1 0 0.025 0 0 0.025 0.1 0 0.025 0.2 0 0.025 0.3 0 0.025 # calibration marks at y = 0.1 m -0.3 0.1 0.025 -0.2 0.1 0.025 -0.1 0.1 0.025 0 0.1 0.025 0.1 0.1 0.025 0.2 0.1 0.025 0.3 0.1 0.025 # calibration marks at y = 0.2 m -0.3 0.2 0.025 -0.2 0.2 0.025 -0.1 0.2 0.025 0 0.2 0.025 0.1 0.2 0.025 0.2 0.2 0.025 0.3 0.2 0.025 # calibration marks at y = 0.3 m -0.3 0.3 0.025 -0.2 0.3 0.025 -0.1 0.3 0.025 0 0.3 0.025 0.1 0.3 0.025 0.2 0.3 0.025 0.3 0.3 0.025
The file CalTabFile contains the corresponding PostScript description of the calibration plate.
Depending on the accuracy of the used output device (e.g., laser printer), the printed calibration plate may not match the values in the calibration plate description file CalTabDescrFile exactly. Thus, the coordinates of the calibration marks in the calibration plate description file may have to be corrected!
Width of the calibration plate in meters.
Default value: 0.8
Suggested values: 1.2, 0.8, 0.6, 0.4, 0.2, 0.1
Recommended increment: 0.1
Restriction: 0.0 < Width
File name of the calibration plate description.
Default value: 'caltab.descr'
List of values: 'caltab.descr', 'caltab_100mm.descr', 'caltab_10mm.descr', 'caltab_200mm.descr', 'caltab_30mm.descr'
File extension: .descr
File name of the PostScript file.
Default value: 'caltab.ps'
File extension: .ps
* create calibration plate with width = 80 cm create_caltab(0.8, 'caltab.descr', 'caltab.ps')
create_caltab returns 2 (H_MSG_TRUE) if all parameter values are correct and both files have been written successfully. If necessary, an exception is raised.
gen_caltab, find_caltab, find_marks_and_pose, camera_calibration, disp_caltab, sim_caltab
Foundation
| Operators |