inverse_project_pixel ( : : Row, Column, CamParam : X, Y, Z )

Inverse projection of a pixel into focal plane.

inverse_project_pixel is used for the inverse projection, i.e., for each pixel (Row,Column) in the image plane the corresponding line of sight is computed taking into account the underlying camera model (pinhole camera with radial distortions with internal camera parameters CamParam). The line of sight is determined by the origin of the camera coordinate system and a point (X,Y,Z) in the focal plane. Thereby, the output parameter Z is equivalent to the focal length of the camera.


Parameters

Row (input_control)
real-array -> real
Row-coordinates of pixels.

Column (input_control)
real-array -> real
Column-coordinates of pixels.

CamParam (input_control)
number-array -> real / integer
Internal camera parameters.
Number of elements: 8

X (output_control)
real-array -> real
X-coordinates of the 3D points in focal plane.
Default value: 'FocalX'

Y (output_control)
real-array -> real
Y-coordinates of the 3D points in focal plane.
Default value: 'FocalY'

Z (output_control)
real-array -> real
Z-coordinates of the 3D points in focal plane.
Default value: 'FocalZ'


Example
/* get internal camera parameters */
read_cam_par(::'campar.dat':CamParam) >
/* inverse projection */
inverse_project_pixel(::[50,100],[100,200],CamParam:X,Y,Z).

Result

inverse_project_pixel returns TRUE if all parameter values are correct. If necessary an exception is raised.


Possible Predecessors

read_cam_par, camera_calibration


Possible Successors

hom_3d_trans


See also

camera_calibration, disp_caltab, read_cam_par, project_3d_point, hom_3d_trans



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