contour_to_world_plane_xldT_contour_to_world_plane_xldContourToWorldPlaneXldContourToWorldPlaneXldcontour_to_world_plane_xld (Operator)

Name

contour_to_world_plane_xldT_contour_to_world_plane_xldContourToWorldPlaneXldContourToWorldPlaneXldcontour_to_world_plane_xld — Transform an XLD contour into the plane z=0 of a world coordinate system.

Signature

Description

The operator contour_to_world_plane_xldcontour_to_world_plane_xldContourToWorldPlaneXldContourToWorldPlaneXldcontour_to_world_plane_xld transforms contour points given in ContoursContoursContourscontourscontours into the plane z=0 in a world coordinate system and returns the 3D contour points in ContoursTransContoursTransContoursTranscontoursTranscontours_trans. The world coordinate system is chosen by passing its 3D pose relative to the camera coordinate system in WorldPoseWorldPoseWorldPoseworldPoseworld_pose. Hence, latter one is expected in the form , where ccs denotes the camera coordinate system and wcs the world coordinate system (see Transformations / Poses and “Solution Guide III-C - 3D Vision”). In CameraParamCameraParamCameraParamcameraParamcamera_param you must pass the internal camera parameters (see Calibration for the sequence of the parameters and the underlying camera model).

In many cases CameraParamCameraParamCameraParamcameraParamcamera_param and WorldPoseWorldPoseWorldPoseworldPoseworld_pose are the result of calibrating the camera with the operator calibrate_camerascalibrate_camerasCalibrateCamerasCalibrateCamerascalibrate_cameras. See below for an example.

With the parameter ScaleScaleScalescalescale you can scale the resulting 3D coordinates. The parameter ScaleScaleScalescalescale must be specified as the ratio desired unit/original unit. The original unit is determined by the coordinates of the calibration object. If the original unit is meters (which is the case if you use the standard calibration plate), you can set the desired unit directly by selecting 'm'"m""m""m""m", 'cm'"cm""cm""cm""cm", 'mm'"mm""mm""mm""mm" or 'um'"um""um""um""um" for the parameter ScaleScaleScalescalescale.

Internally, the operator first computes the line of sight between the projection center and the image point in the camera coordinate system, taking into account the radial distortions. The line of sight is then transformed into the world coordinate system specified in WorldPoseWorldPoseWorldPoseworldPoseworld_pose. By intersecting the plane z=0 with the line of sight the 3D coordinates of the transformed contour ContoursTransContoursTransContoursTranscontoursTranscontours_trans are obtained.

Execution Information

• Multithreading type: reentrant (runs in parallel with non-exclusive operators).
• Multithreading scope: global (may be called from any thread).
• Processed without parallelization.

Parameters

Example (HDevelop)

*  Perform camera calibration (with standard calibration plate).
calibrate_cameras (CalibDataID, Error)
get_calib_data (CalibDataID, 'camera', 0, 'params', CamParam)
* Get reference pose (pose 2 of calibration object 0).
get_calib_data (CalibDataID, 'calib_obj_pose', [0,2], 'pose', WorldPose)
*  Compensate thickness of plate.
set_origin_pose(ObjInCameraPose, 0, 0, 0.0006, WorldPose)
*  Transform contours into world coordinate system (unit mm).
contour_to_world_plane_xld(Contours, ContoursTrans, CamParam, \
                           WorldPose, 'mm')

Result

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

Possible Predecessors

create_posecreate_poseCreatePoseCreatePosecreate_pose, hom_mat3d_to_posehom_mat3d_to_poseHomMat3dToPoseHomMat3dToPosehom_mat3d_to_pose, camera_calibrationcamera_calibrationCameraCalibrationCameraCalibrationcamera_calibration, hand_eye_calibrationhand_eye_calibrationHandEyeCalibrationHandEyeCalibrationhand_eye_calibration, set_origin_poseset_origin_poseSetOriginPoseSetOriginPoseset_origin_pose

See also

image_points_to_world_planeimage_points_to_world_planeImagePointsToWorldPlaneImagePointsToWorldPlaneimage_points_to_world_plane

Module

Calibration