ArUco Marker Detection

Instance declaration

When you add an ArUco Marker Detection block to the workspace, the following instance declaration is automatically inserted into the Python code:

aruco_marker = ArucoMarker(0)
# When there are multiple instances
aruco_marker_1 = ArucoMarker(1)

Parameters

Name	Kind	Description	Range / Type	Default
index	Dropdown option	Instance number (starting from 0)	Integer 0 or greater	0

Select the camera device

Sets the camera to use for ArUco marker detection.

Parameters

Name	Kind	Description	Range / Type	Default
unit	Dropdown option	Camera device name	System camera label	-

Python

aruco_marker = ArucoMarker(0)

aruco_marker.device('')

Set the maximum marker count

Sets the maximum number of markers that can be recognized. The marker count ranges from 0 to 10.

Parameters

Name	Kind	Description	Range / Type	Default
data	Input (block)	Maximum marker count	Integer 0 to 10	-

Python

aruco_marker = ArucoMarker(0)

aruco_marker.max_count(5)

Detect once

Finds the markers currently on screen and marks their regions just once.

Parameters

(none)

Python

aruco_marker = ArucoMarker(0)

aruco_marker.detect_once()

Start / stop continuous detection

Keeps following the markers currently on screen and marks their regions on the screen.

Parameters

Name	Kind	Description	Range / Type	Default
unit	Dropdown option	Action	start, stop	-

Python

aruco_marker = ArucoMarker(0)

# unit = "start"
aruco_marker.detect_continuous()
# unit = "stop"
aruco_marker.stop()

Show the detection result

Decides whether or not to show the marker detection result on the camera screen.

Parameters

Name	Kind	Description	Range / Type	Default
on	Dropdown option	Display ON / OFF	show (on=True), hide (off=False)	TRUE

Python

aruco_marker = ArucoMarker(0)

aruco_marker.display(True)
aruco_marker.display(False)

Marker data

Returns the position/size values of the specified marker ID.

Parameters

Name	Kind	Description	Range / Type	Default
data	Input (block)	Marker ID	Integer 0 or greater	-
unit	Dropdown option	Kind of measurement	x, y, min_x, max_x, min_y, max_y, width, height, area, rotation	-

Python

aruco_marker = ArucoMarker(0)

aruco_marker.marker(0, 'x')
aruco_marker.marker(3, 'area')

Distance between markers

Returns the distance between two markers.

Parameters

Name	Kind	Description	Range / Type	Default
unit1	Input (block)	First marker ID	Integer 0 or greater	-
unit2	Input (block)	Second marker ID	Integer 0 or greater	-
type	Dropdown option	Kind of distance	distance (omitted or None), horizontal distance (horizontal), vertical distance (vertical)	None

Python

aruco_marker = ArucoMarker(0)

aruco_marker.get_distance(0, 1)  # distance
aruco_marker.get_distance(0, 2, 'horizontal')  # horizontal distance

Whether a marker was detected

Whether a marker with the given id value was found

Parameters

Name	Kind	Description	Range / Type	Default
data	Input (block)	Marker ID	Integer 0 or greater	-

Python

aruco_marker = ArucoMarker(0)

aruco_marker.marker_detected(0)