HALCON 18.11.0.0 / HALCON Operator Reference / Calibration / Inverse Projection
ClassesClasses | | Operators

get_line_of_sightT_get_line_of_sightGetLineOfSightGetLineOfSight (Operator)

Name

get_line_of_sightT_get_line_of_sightGetLineOfSightGetLineOfSight — Compute the line of sight corresponding to a point in the image.

Signature

get_line_of_sight( : : Row, Column, CameraParam : PX, PY, PZ, QX, QY, QZ)

Herror T_get_line_of_sight(const Htuple Row, const Htuple Column, const Htuple CameraParam, Htuple* PX, Htuple* PY, Htuple* PZ, Htuple* QX, Htuple* QY, Htuple* QZ)

void GetLineOfSight(const HTuple& Row, const HTuple& Column, const HTuple& CameraParam, HTuple* PX, HTuple* PY, HTuple* PZ, HTuple* QX, HTuple* QY, HTuple* QZ)

void HCamPar::GetLineOfSight(const HTuple& Row, const HTuple& Column, HTuple* PX, HTuple* PY, HTuple* PZ, HTuple* QX, HTuple* QY, HTuple* QZ) const

static void HOperatorSet.GetLineOfSight(HTuple row, HTuple column, HTuple cameraParam, out HTuple PX, out HTuple PY, out HTuple PZ, out HTuple QX, out HTuple QY, out HTuple QZ)

void HCamPar.GetLineOfSight(HTuple row, HTuple column, out HTuple PX, out HTuple PY, out HTuple PZ, out HTuple QX, out HTuple QY, out HTuple QZ)

Description

get_line_of_sightget_line_of_sightGetLineOfSightGetLineOfSightGetLineOfSight computes the line of sight corresponding to a pixel (RowRowRowRowrow, ColumnColumnColumnColumncolumn) in the image. The line of sight is a (straight) line in the camera coordinate system, which is described by two points (PXPXPXPXPX,PYPYPYPYPY,PZPZPZPZPZ) and (QXQXQXQXQX,QYQYQYQYQY,QZQZQZQZQZ) on the line. The camera is described by the internal camera parameters CameraParamCameraParamCameraParamCameraParamcameraParam (see Calibration / Multi-View for details). If a pinhole camera is used, the second point lies on the focal plane, i.e., for frame cameras, the output parameter QZQZQZQZQZ is equivalent to the focal length of the camera, whereas for linescan cameras, QZQZQZQZQZ also depends on the motion of the camera with respect to the object. The equation of the line of sight is given by

The advantage of representing the line of sight as two points is that it is easier to transform the line in 3D. To do so, all that is necessary is to apply the operator affine_trans_point_3daffine_trans_point_3dAffineTransPoint3dAffineTransPoint3dAffineTransPoint3d to the two points.

Execution Information

Parameters

RowRowRowRowrow (input_control)  real-array → HTupleHTupleHtuple (real) (double) (double) (double)

Row coordinate of the pixel.

ColumnColumnColumnColumncolumn (input_control)  real-array → HTupleHTupleHtuple (real) (double) (double) (double)

Column coordinate of the pixel.

CameraParamCameraParamCameraParamCameraParamcameraParam (input_control)  campar → HCamPar, HTupleHTupleHtuple (real / integer / string) (double / int / long / string) (double / Hlong / HString) (double / Hlong / char*)

Internal camera parameters.

PXPXPXPXPX (output_control)  real-array → HTupleHTupleHtuple (real) (double) (double) (double)

X coordinate of the first point on the line of sight in the camera coordinate system

PYPYPYPYPY (output_control)  real-array → HTupleHTupleHtuple (real) (double) (double) (double)

Y coordinate of the first point on the line of sight in the camera coordinate system

PZPZPZPZPZ (output_control)  real-array → HTupleHTupleHtuple (real) (double) (double) (double)

Z coordinate of the first point on the line of sight in the camera coordinate system

QXQXQXQXQX (output_control)  real-array → HTupleHTupleHtuple (real) (double) (double) (double)

X coordinate of the second point on the line of sight in the camera coordinate system

QYQYQYQYQY (output_control)  real-array → HTupleHTupleHtuple (real) (double) (double) (double)

Y coordinate of the second point on the line of sight in the camera coordinate system

QZQZQZQZQZ (output_control)  real-array → HTupleHTupleHtuple (real) (double) (double) (double)

Z coordinate of the second point on the line of sight in the camera coordinate system

Example (HDevelop)

* Set internal camera parameters.
* Note the, typically, these values are the result of a prior
* calibration.
gen_cam_par_area_scan_division (0.01, 30, 4.65e-006, 4.65e-006, \
                                640, 480, 1280, 960, CameraParam)
* Inverse projection.
get_line_of_sight([50, 100], [100, 200], CameraParam, PX, PY, PZ, QX, QY, QZ)

Example (HDevelop)

* Set internal camera parameters.
* Note the, typically, these values are the result of a prior
* calibration.
gen_cam_par_area_scan_division (0.01, 30, 4.65e-006, 4.65e-006, \
                                640, 480, 1280, 960, CameraParam)
* Inverse projection.
get_line_of_sight([50, 100], [100, 200], CameraParam, PX, PY, PZ, QX, QY, QZ)

Example (HDevelop)

* Set internal camera parameters.
* Note the, typically, these values are the result of a prior
* calibration.
gen_cam_par_area_scan_division (0.01, 30, 4.65e-006, 4.65e-006, \
                                640, 480, 1280, 960, CameraParam)
* Inverse projection.
get_line_of_sight([50, 100], [100, 200], CameraParam, PX, PY, PZ, QX, QY, QZ)

Example (HDevelop)

* Set internal camera parameters.
* Note the, typically, these values are the result of a prior
* calibration.
gen_cam_par_area_scan_division (0.01, 30, 4.65e-006, 4.65e-006, \
                                640, 480, 1280, 960, CameraParam)
* Inverse projection.
get_line_of_sight([50, 100], [100, 200], CameraParam, PX, PY, PZ, QX, QY, QZ)

Example (HDevelop)

* Set internal camera parameters.
* Note the, typically, these values are the result of a prior
* calibration.
gen_cam_par_area_scan_division (0.01, 30, 4.65e-006, 4.65e-006, \
                                640, 480, 1280, 960, CameraParam)
* Inverse projection.
get_line_of_sight([50, 100], [100, 200], CameraParam, PX, PY, PZ, QX, QY, QZ)

Result

get_line_of_sightget_line_of_sightGetLineOfSightGetLineOfSightGetLineOfSight returns 2 (H_MSG_TRUE) if all parameter values are correct. If necessary, an exception is raised.

Possible Predecessors

read_cam_parread_cam_parReadCamParReadCamParReadCamPar, camera_calibrationcamera_calibrationCameraCalibrationCameraCalibrationCameraCalibration

Possible Successors

affine_trans_point_3daffine_trans_point_3dAffineTransPoint3dAffineTransPoint3dAffineTransPoint3d

See also

camera_calibrationcamera_calibrationCameraCalibrationCameraCalibrationCameraCalibration, disp_caltabdisp_caltabDispCaltabDispCaltabDispCaltab, read_cam_parread_cam_parReadCamParReadCamParReadCamPar, project_3d_pointproject_3d_pointProject3dPointProject3dPointProject3dPoint, affine_trans_point_3daffine_trans_point_3dAffineTransPoint3dAffineTransPoint3dAffineTransPoint3d

Module

Calibration

ClassesClasses | | Operators
HALCON Operator Reference 18.11.0.0 Copyright © 1996-2018 MVTec Software GmbH