Table Of Contents

Learn Calibration Camera Model (G Dataflow)

Last Modified: June 25, 2019

Learns detailed camera characteristics, including the focal length, optical center, and distortion model.

Because a camera model includes a distortion model, you do not need to compute a separate distortion model.

connector_pane_image
datatype_icon

distortion model setup

Distortion model settings to use.

datatype_icon

Distortion Model

Type of distortion model.

Name Value Description
None -1

Do not learn a distortion model.

Polynomial 0

Learn a polynomial distortion model. Using multiple coefficients increases computation accuracy at the expense of speed.

Division 1

Learn a division distortion model. Use this distortion model when the image contains minimal distortion.

datatype_icon

Polynomial Model Setup

Polynomial model configuration.

datatype_icon

Radial Coefficient

Number of polynomial coefficients to use.

datatype_icon

Tangential Coefficients

Correction for tangential distortion. Correct for tangential distortion when sensor misalignment occurs.

TRUE Correct for tangential distortion.
FALSE Do not use correction.

Default: TRUE

datatype_icon

reference image

Reference to the image containing calibration information.

datatype_icon

image in

Reference to the source image.

datatype_icon

reference points

Set of reference points to use in learning a calibration. Create the reference points manually or use the Calibration Target to Points - Circular Dots node.

datatype_icon

pixel coordinates

Coordinates of 3 reference points in the image, in pixels.

datatype_icon

X

X-coordinate of the point.

datatype_icon

Y

Y-coordinate of the point.

datatype_icon

Real World Coordinates

Relative locations of the dots in the real world.

datatype_icon

X

X-coordinate of the point.

datatype_icon

Y

Y-coordinate of the point.

datatype_icon

Unit

Unit of the Real World Coordinates.

datatype_icon

Image Size

Size of the calibration template image.

datatype_icon

X

Horizontal size of the image.

datatype_icon

Y

Vertical size of the image.

datatype_icon

error in

Error conditions that occur before this node runs.

The node responds to this input according to standard error behavior.

Standard Error Behavior

Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

error in does not contain an error error in contains an error
If no error occurred before the node runs, the node begins execution normally.

If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.

If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.

Default: No error

datatype_icon

add points and learn

Boolean value that adds points and learns the distortion model.

TRUE Add points and learn the distortion model.
FALSE Add points only.

Default: TRUE

datatype_icon

calibrated image out

Reference to the output image.

datatype_icon

internal parameters

Focal length learned and optical center of the camera model.

datatype_icon

insufficient data

Boolean value that specifies insufficient information.

Possible conditions for insufficient information are the number of different projection planes is fewer than 5, the angle difference of the projection planes is less than 20 degrees, or the lens in use is a telecentric lens.

TRUE One or more insufficient data conditions present
FALSE Sufficient data
datatype_icon

focal length (pixel)

Focal length in pixel units.

Use the following equation to obtain the focal length in real-world units: focal length in millimeters = focal length in pixels x pixel size in millimeters. Refer to your camera documentation to obtain the pixel size.

datatype_icon

fx

Focal length in x direction.

datatype_icon

fy

Focal length in y direction.

datatype_icon

optical center (pixel)

Optical center in image.

datatype_icon

cx

X resolution of the optical center.

datatype_icon

cy

Y resolution of the optical center.

datatype_icon

error out

Error information.

The node produces this output according to standard error behavior.

Standard Error Behavior

Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

error in does not contain an error error in contains an error
If no error occurred before the node runs, the node begins execution normally.

If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.

If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.

Example

The following image shows an example of how to use this VI.

Where This Node Can Run:

Desktop OS: Windows

FPGA: Not supported

Web Server: Not supported in VIs that run in a web application


Recently Viewed Topics