IMAQ MagicWand VI

LabView NI Vision

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IMAQ MagicWand VI

Owning Palette: ProcessingInstalled With: NI Vision Development Module

Creates an image mask by extracting a region surrounding a reference pixel, called the origin, and using a tolerance of intensity variations based on this reference pixel. Using this origin, the VI searches for its neighbors with an intensity that equals or falls within the tolerance value of the point of reference. The resulting image is binary. The image passed as input for Image Dst must be an 8-bit image. If the same image is entered for Image Src and Image Dst, the image must be an 8-bit image.

Examples

IMAQ MagicWand

Connectivity 4/8 (8) specifies the type of connectivity used by the algorithm for particle detection. The connectivity mode directly determines whether an adjacent pixel belongs to the same particle or a different particle. The default is 8. The following values are possible:

8 (TRUE)	Particle detection is performed in connectivity mode 8
4 (FALSE)	Particle detection is performed in connectivity mode 4

Fill Value is the value used for the highlighted pixels in the destination image. The default is 1.

Image Src is a reference to the source image.

Image Dst is a reference to the destination image.

Hot spot (x,y) is an array containing the (x, y) coordinates of the origin pixel chosen from the image source.

error in (no error) describes the error status before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node.

	status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE.
	code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code.
	source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.

Tolerance is the maximum allowed deviation from the origin. All pixels satisfying the tolerance criteria (between origin pixel –tolerance and origin pixel +tolerance) and connectivity criteria (as specified in Connectivity 4/8 (8)), are highlighted. All other pixels are turned off. The default is 20.

Image Dst Out is a reference to the destination image. If Image Dst is connected, Image Dst Out is the same as Image Dst. Otherwise, Image Dst Out refers to the image referenced by Image Src.

error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out indicator on the front panel and select Explain Error from the shortcut menu for more information about the error.

	status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred.
	code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code.
	source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.

Examples

Refer to the following for an example that uses this VI.

LabVIEW\examples\Vision\2. Functions\Grayscale Processing\MagicWand Example.vi

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