Vision¶

Vision - Localize Pattern 2D¶

Localizes the center of a given template image inside the current camera image. It is possible to define a region of interest (ROI) within the camera image to search for the object. The pixel positions U and V and the localized pose in world coordinates are returned. The function block uses homography based on the points obtained from SIFT algorithm.

	Name	Data type	Description
Inputs	Template Image	String	Template image of the object to be localized. The file needs to be placed in the directory `~/.dnb/data/vision/`. Several files can be stated comma-separated.
	ROI: X1	Integer	X value of top left corner of the ROI in pixels.
	ROI: Y1	Integer	Y value of top left corner of the ROI in pixels.
	ROI: X2	Integer	X value of bottom right corner of the ROI in pixels. A value of -1 takes the image width.
	ROI: Y2	Integer	Y value of bottom right corner of the ROI in pixels. A value of -1 takes the image height.
	Result: Minimum Match Points	Integer	Minimum number of matching points to return a success.
	Result: Ignore Orientation	Boolean	True: The orientation of the detected pattern is ignored.
	ROS Camera Topic	String	The name of the camera image stream.
	Extrinsic Calibration Name	String	The name of the calibration file e.g. 'default'
	Image Encoding	String	Encoding of the camera image.

Outputs	Pixel U	Integer	Pixel coordinate U in the image of the camera topic.
	Pixel V	Integer	Pixel coordinate V in the image of the camera topic.
	Localized Position	Pose	World pose of the localized object.
	Success	Boolean	True if detection was successful. False otherwise.
	Image Found	String	The filename of the image for the case several template images have been configured.

Exceptions	CALIBRATION_EXCEPTION	-	The exception is raised, if the Vision Module Component is not started or the calibration saved there is not valid.
	TEMPLATE_FILE_NOT_FOUND	-	The exception is raised, if the template image file can not be found.
	SCENE_ERROR	-	The exception is raised, if the observed scene could not be processed.

Vision - Save Camera Image¶

Saves the current camera image as JPEG file.

	Name	Data type	Description
Inputs	Camera Image Topic	String	The name of a ROS image stream topic.
	Filename	String	The name of the filename. The file can be found later in the directory `~/.dnb/data/vision/images_saved/`
	File Format	Select	Format of the saved image file. Available are: jpeg, png

Outputs	-

Vision - Localize Rectangle 2D¶

Localizes the center if a given rectangle inside the current camera image. It is possible to define a region of interest (ROI) within the camera image to search for the rectangle. The pixel positions U and V and the localized pose in world coordinates are returned.

	Name	Data type	Description
Inputs	Filter: Rectangle Length	Integer	Length of longer side of rectangle in mm.
	Filter: Rectangle Width	Integer	Length of shorter side of rectangle in mm.
	Filter: Lenghts Tolerance	Integer	Tolerance of rectangle length and width in ±mm.
	Vision: Bright Background	Boolean	True: bright background; False: dark background
	Vision: Gaussian Blur Kernel Size	Integer	Kernel size in pixels. The kernel size needs to be positive and odd.
	Vision: Binary Threshold	Integer	Threshold within [0..255].
	ROI: X1	Integer	X value of top left corner of the ROI in pixels.
	ROI: Y1	Integer	Y value of top left corner of the ROI in pixels.
	ROI: X2	Integer	X value of bottom right corner of the ROI in pixels. A value of -1 takes the image width.
	ROI: Y2	Integer	Y value of bottom right corner of the ROI in pixels. A value of -1 takes the image height.
	Result: Orientation Alignment	Boolean	Should orientation/angle be parallel to long edge? true: yes; false: no/short edge
	Result: Favorite Angle	Integer	Close to which angle in degree the returned orientation should be.
	ROS Camera Topic	String	The name of the camera image stream.
	Extrinsic Calibration Name	String	The name of the calibration file e.g. 'default'
	Image Encoding	String	Encoding of the camera image.

Outputs	Pixel U	Integer	Coordinate U in pixels in the image of the camera topic.
	Pixel V	Integer	Coordinate V in pixels in the image of the camera topic.
	Localized Position	Pose	World pose of the localized rectangle.
	Success	Boolean	True if detection was successful. False otherwise.

Exceptions	CALIBRATION_EXCEPTION	-	The exception is raised, if the Vision Module Component is not started or the calibration saved there is not valid.

Vision - QR Code Reader¶

Localizes and decodes the barcodes (EAN-13/UPC-A, UPC-E, EAN-8, Code 128, Code 39, Interleaved 2 of 5) and QR Codes. It is possible to define a region of interest (ROI) within the camera image to search for the code. The pixel positions U and V and the localized pose in world coordinates are returned.

	Name	Data type	Description
Inputs	ROI: X1	Integer	X value of top left corner of the ROI in pixels.
	ROI: Y1	Integer	Y value of top left corner of the ROI in pixels.
	ROI: X2	Integer	X value of bottom right corner of the ROI in pixels. A value of -1 takes the image width.
	ROI: Y2	Integer	Y value of bottom right corner of the ROI in pixels. A value of -1 takes the image height.
	ROS Camera Topic	String	The name of the camera image stream.
	Extrinsic Calibration Name	String	The name of the calibration file e.g. 'default'
	Image Encoding	String	Encoding of the camera image.

Outputs	Pixel U	Integer	Coordinate U in pixels in the image of the camera topic.
	Pixel V	Integer	Coordinate V in pixels in the image of the camera topic.
	Localized Position	Pose	World pose of the localized rectangle.
	Success	Boolean	True if detection was successful. False otherwise.
	Decoded Text	String	The text contained in the recognized barcode or QR Code.
	Code Type	String	Type of the recognized code.

Exceptions	CALIBRATION_EXCEPTION	-	The exception is raised, if the Vision Module Component is not started or the calibration saved there is not valid.