ClassesClasses | | Operators

gen_image_to_world_plane_mapT_gen_image_to_world_plane_mapGenImageToWorldPlaneMapGenImageToWorldPlaneMap (Operator)

Name

gen_image_to_world_plane_mapT_gen_image_to_world_plane_mapGenImageToWorldPlaneMapGenImageToWorldPlaneMap — Generate a projection map that describes the mapping between the image plane and a the plane z=0 of a world coordinate system.

Signature

gen_image_to_world_plane_map( : Map : CameraParam, WorldPose, WidthIn, HeightIn, WidthMapped, HeightMapped, Scale, MapType : )

Herror T_gen_image_to_world_plane_map(Hobject* Map, const Htuple CameraParam, const Htuple WorldPose, const Htuple WidthIn, const Htuple HeightIn, const Htuple WidthMapped, const Htuple HeightMapped, const Htuple Scale, const Htuple MapType)

void GenImageToWorldPlaneMap(HObject* Map, const HTuple& CameraParam, const HTuple& WorldPose, const HTuple& WidthIn, const HTuple& HeightIn, const HTuple& WidthMapped, const HTuple& HeightMapped, const HTuple& Scale, const HTuple& MapType)

void HImage::GenImageToWorldPlaneMap(const HCamPar& CameraParam, const HPose& WorldPose, Hlong WidthIn, Hlong HeightIn, Hlong WidthMapped, Hlong HeightMapped, const HTuple& Scale, const HString& MapType)

void HImage::GenImageToWorldPlaneMap(const HCamPar& CameraParam, const HPose& WorldPose, Hlong WidthIn, Hlong HeightIn, Hlong WidthMapped, Hlong HeightMapped, const HString& Scale, const HString& MapType)

void HImage::GenImageToWorldPlaneMap(const HCamPar& CameraParam, const HPose& WorldPose, Hlong WidthIn, Hlong HeightIn, Hlong WidthMapped, Hlong HeightMapped, const char* Scale, const char* MapType)

HImage HCamPar::GenImageToWorldPlaneMap(const HPose& WorldPose, Hlong WidthIn, Hlong HeightIn, Hlong WidthMapped, Hlong HeightMapped, const HTuple& Scale, const HString& MapType) const

HImage HCamPar::GenImageToWorldPlaneMap(const HPose& WorldPose, Hlong WidthIn, Hlong HeightIn, Hlong WidthMapped, Hlong HeightMapped, const HString& Scale, const HString& MapType) const

HImage HCamPar::GenImageToWorldPlaneMap(const HPose& WorldPose, Hlong WidthIn, Hlong HeightIn, Hlong WidthMapped, Hlong HeightMapped, const char* Scale, const char* MapType) const

HImage HPose::GenImageToWorldPlaneMap(const HCamPar& CameraParam, Hlong WidthIn, Hlong HeightIn, Hlong WidthMapped, Hlong HeightMapped, const HTuple& Scale, const HString& MapType) const

HImage HPose::GenImageToWorldPlaneMap(const HCamPar& CameraParam, Hlong WidthIn, Hlong HeightIn, Hlong WidthMapped, Hlong HeightMapped, const HString& Scale, const HString& MapType) const

HImage HPose::GenImageToWorldPlaneMap(const HCamPar& CameraParam, Hlong WidthIn, Hlong HeightIn, Hlong WidthMapped, Hlong HeightMapped, const char* Scale, const char* MapType) const

static void HOperatorSet.GenImageToWorldPlaneMap(out HObject map, HTuple cameraParam, HTuple worldPose, HTuple widthIn, HTuple heightIn, HTuple widthMapped, HTuple heightMapped, HTuple scale, HTuple mapType)

void HImage.GenImageToWorldPlaneMap(HCamPar cameraParam, HPose worldPose, int widthIn, int heightIn, int widthMapped, int heightMapped, HTuple scale, string mapType)

void HImage.GenImageToWorldPlaneMap(HCamPar cameraParam, HPose worldPose, int widthIn, int heightIn, int widthMapped, int heightMapped, string scale, string mapType)

HImage HCamPar.GenImageToWorldPlaneMap(HPose worldPose, int widthIn, int heightIn, int widthMapped, int heightMapped, HTuple scale, string mapType)

HImage HCamPar.GenImageToWorldPlaneMap(HPose worldPose, int widthIn, int heightIn, int widthMapped, int heightMapped, string scale, string mapType)

HImage HPose.GenImageToWorldPlaneMap(HCamPar cameraParam, int widthIn, int heightIn, int widthMapped, int heightMapped, HTuple scale, string mapType)

HImage HPose.GenImageToWorldPlaneMap(HCamPar cameraParam, int widthIn, int heightIn, int widthMapped, int heightMapped, string scale, string mapType)

Description

gen_image_to_world_plane_mapgen_image_to_world_plane_mapGenImageToWorldPlaneMapGenImageToWorldPlaneMapGenImageToWorldPlaneMap generates a projection map MapMapMapMapmap, which describes the mapping between the image plane and the plane z=0 (plane of measurements) in a world coordinate system. This map can be used to rectify an image with the operator map_imagemap_imageMapImageMapImageMapImage. The rectified image shows neither radial nor perspective distortions; it corresponds to an image acquired by a distortion-free camera that looks perpendicularly onto the plane of measurements. The world coordinate system is chosen by passing its 3D pose relative to the camera coordinate system in WorldPoseWorldPoseWorldPoseWorldPoseworldPose. In CameraParamCameraParamCameraParamCameraParamcameraParam you must pass the internal camera parameters (see calibrate_camerascalibrate_camerasCalibrateCamerasCalibrateCamerasCalibrateCameras for the sequence of the parameters and the underlying camera model).

In many cases CameraParamCameraParamCameraParamCameraParamcameraParam and WorldPoseWorldPoseWorldPoseWorldPoseworldPose are the result of calibrating the camera with the operator calibrate_camerascalibrate_camerasCalibrateCamerasCalibrateCamerasCalibrateCameras. See below for an example.

The size of the images to be mapped can be specified by the parameters WidthInWidthInWidthInWidthInwidthIn and HeightInHeightInHeightInHeightInheightIn. The pixel position of the upper left corner of the output image is determined by the origin of the world coordinate system. The size of the output image can be chosen by the parameters WidthMappedWidthMappedWidthMappedWidthMappedwidthMapped, HeightMappedHeightMappedHeightMappedHeightMappedheightMapped, and ScaleScaleScaleScalescale. WidthMappedWidthMappedWidthMappedWidthMappedwidthMapped and HeightMappedHeightMappedHeightMappedHeightMappedheightMapped must be given in pixels.

With the parameter ScaleScaleScaleScalescale you can specify the size of a pixel in the transformed image. There are two typical scenarios: First, you can scale the image such that pixel coordinates in the transformed image directly correspond to metric units, e.g., that one pixel corresponds to one micron. This is useful if you want to perform measurements in the transformed image which will then directly result in metric results. The second scenario is to scale the image such that its content appears in a size similar to the original image. This is useful, e.g., if you want to perform shape-based matching in the transformed image.

ScaleScaleScaleScalescale must be specified as the ratio desired pixel size/original unit. A pixel size of 1um means that a pixel in the transformed image corresponds to the area 1um x 1um in the plane of measurements. 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 use the parameter values 'm'"m""m""m""m", 'cm'"cm""cm""cm""cm", 'mm'"mm""mm""mm""mm", 'microns'"microns""microns""microns""microns", or 'um'"um""um""um""um" to directly set the unit of pixel coordinates in the transformed image.

The mapping function is stored in the output image MapMapMapMapmap. MapMapMapMapmap has the same size as the resulting images after the mapping. MapTypeMapTypeMapTypeMapTypemapType is used to specify the type of the output MapMapMapMapmap. If 'nearest_neighbor'"nearest_neighbor""nearest_neighbor""nearest_neighbor""nearest_neighbor" is chosen, MapMapMapMapmap consists of one image containing one channel, in which for each pixel of the resulting image the linearized coordinate of the pixel of the input image is stored that is the nearest neighbor to the transformed coordinates. If 'bilinear'"bilinear""bilinear""bilinear""bilinear" interpolation is chosen, MapMapMapMapmap consists of one image containing five channels. In the first channel for each pixel in the resulting image the linearized coordinates of the pixel in the input image is stored that is in the upper left position relative to the transformed coordinates. The four other channels contain the weights of the four neighboring pixels of the transformed coordinates which are used for the bilinear interpolation, in the following order:

2 3
4 5

The second channel, for example, contains the weights of the pixels that lie to the upper left relative to the transformed coordinates. If 'coord_map_sub_pix'"coord_map_sub_pix""coord_map_sub_pix""coord_map_sub_pix""coord_map_sub_pix" is chosen, MapMapMapMapmap consists of one vector field image of the semantic type 'vector_field_absolute', in which for each pixel of the resulting image the subpixel precise coordinates in the input image are stored.

If several images have to be mapped using the same camera parameters, gen_image_to_world_plane_mapgen_image_to_world_plane_mapGenImageToWorldPlaneMapGenImageToWorldPlaneMapGenImageToWorldPlaneMap in combination with map_imagemap_imageMapImageMapImageMapImage is much more efficient than the operator image_to_world_planeimage_to_world_planeImageToWorldPlaneImageToWorldPlaneImageToWorldPlane because the mapping function needs to be computed only once.

If you want to re-use the created map in another program, you can save it as a multi-channel image with the operator write_imagewrite_imageWriteImageWriteImageWriteImage, using the format 'tiff'"tiff""tiff""tiff""tiff".

Execution Information

Parameters

MapMapMapMapmap (output_object)  (multichannel-)image objectHImageHImageHobject * (int4 / int8 / uint2 / vector_field)

Image containing the mapping data.

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

Internal camera parameters.

WorldPoseWorldPoseWorldPoseWorldPoseworldPose (input_control)  pose HPose, HTupleHTupleHtuple (real / integer) (double / int / long) (double / Hlong) (double / Hlong)

3D pose of the world coordinate system in camera coordinates.

Number of elements: 7

WidthInWidthInWidthInWidthInwidthIn (input_control)  extent.x HTupleHTupleHtuple (integer) (int / long) (Hlong) (Hlong)

Width of the images to be transformed.

Restriction: WidthIn >= 1

HeightInHeightInHeightInHeightInheightIn (input_control)  extent.y HTupleHTupleHtuple (integer) (int / long) (Hlong) (Hlong)

Height of the images to be transformed.

Restriction: HeightIn >= 1

WidthMappedWidthMappedWidthMappedWidthMappedwidthMapped (input_control)  extent.x HTupleHTupleHtuple (integer) (int / long) (Hlong) (Hlong)

Width of the resulting mapped images in pixels.

Restriction: WidthMapped >= 1

HeightMappedHeightMappedHeightMappedHeightMappedheightMapped (input_control)  extent.y HTupleHTupleHtuple (integer) (int / long) (Hlong) (Hlong)

Height of the resulting mapped images in pixels.

Restriction: HeightMapped >= 1

ScaleScaleScaleScalescale (input_control)  number HTupleHTupleHtuple (string / integer / real) (string / int / long / double) (HString / Hlong / double) (char* / Hlong / double)

Scale or unit.

Default value: 'm' "m" "m" "m" "m"

Suggested values: 'm'"m""m""m""m", 'cm'"cm""cm""cm""cm", 'mm'"mm""mm""mm""mm", 'microns'"microns""microns""microns""microns", 'um'"um""um""um""um", 1.0, 0.01, 0.001, 1.0e-6, 0.0254, 0.3048, 0.9144

Restriction: Scale > 0

MapTypeMapTypeMapTypeMapTypemapType (input_control)  string HTupleHTupleHtuple (string) (string) (HString) (char*)

Type of the mapping.

Default value: 'bilinear' "bilinear" "bilinear" "bilinear" "bilinear"

List of values: 'bilinear'"bilinear""bilinear""bilinear""bilinear", 'coord_map_sub_pix'"coord_map_sub_pix""coord_map_sub_pix""coord_map_sub_pix""coord_map_sub_pix", 'nearest_neighbor'"nearest_neighbor""nearest_neighbor""nearest_neighbor""nearest_neighbor"

Example (HDevelop)

* Calibrate camera.
calibrate_cameras (CalibDataID, Error)
* Obtain camera parameters.
get_calib_data (CalibDataID, 'camera', 0, 'params', CamParam)
* Example values, if no calibration data is available:
CamParam := ['area_scan_division', 0.0087, -1859, 8.65e-006, 8.6e-006, \
             362.5, 291.6, 768, 576]
* Get reference pose (pose 4 of calibration object 0).
get_calib_data (CalibDataID, 'calib_obj_pose',\
                [0,4], 'pose', Pose)
* Example values, if no calibration data is available:
Pose := [-0.11, -0.21, 2.51, 352.73, 346.73, 336.48, 0]
* Compensate thickness of plate.
set_origin_pose (Pose, -1.125, -1.0, 0, PoseNewOrigin)
* Transform the image into the world plane.
read_image (Image, 'calib/calib-3d-coord-04')
gen_image_to_world_plane_map (MapSingle, CamParam, PoseNewOrigin,\
                  CamParam[6], CamParam[7], 900, 800, 0.0025, 'bilinear')
map_image (Image, MapSingle, ImageMapped)

Result

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

Possible Predecessors

create_posecreate_poseCreatePoseCreatePoseCreatePose, hom_mat3d_to_posehom_mat3d_to_poseHomMat3dToPoseHomMat3dToPoseHomMat3dToPose, camera_calibrationcamera_calibrationCameraCalibrationCameraCalibrationCameraCalibration, hand_eye_calibrationhand_eye_calibrationHandEyeCalibrationHandEyeCalibrationHandEyeCalibration, set_origin_poseset_origin_poseSetOriginPoseSetOriginPoseSetOriginPose

Possible Successors

map_imagemap_imageMapImageMapImageMapImage

Alternatives

image_to_world_planeimage_to_world_planeImageToWorldPlaneImageToWorldPlaneImageToWorldPlane

See also

map_imagemap_imageMapImageMapImageMapImage, contour_to_world_plane_xldcontour_to_world_plane_xldContourToWorldPlaneXldContourToWorldPlaneXldContourToWorldPlaneXld, image_points_to_world_planeimage_points_to_world_planeImagePointsToWorldPlaneImagePointsToWorldPlaneImagePointsToWorldPlane

Module

Calibration


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