IMAQ Particle Analysis Report VI

LabView NI Vision

IMAQ Particle Analysis Report VI

Owning Palette: AnalysisInstalled With: NI Vision Development Module

Returns the number of particles detected in a binary image and an array of reports containing the most commonly used particle measurements.

Note This VI modifies the source image. If you need the original source image, Create a copy of the image using the IMAQ Copy VI before using this VI.

Examples

IMAQ Particle Analysis Report

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

Image is a reference to the source image.

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.

Number of Particles indicates the number of particles detected in the image.

Image Out (duplicate) is a reference to the Image input.

Particle Reports (Pixels) is an array that returns a set of uncalibrated pixel measurements from the detected particles. This cluster contains the following elements:

	Area is the area of the particle.
	Number of Holes is the number of holes in the particle. NI Vision can detect holes inside a particle as small as one pixel.
	Bounding Rect is the smallest rectangle with sides parallel to the x-axis and y-axis that completely encloses the particle.
	Center of Mass is the point representing the average position of the total mass of the particle assuming every point in the particle has a constant density. Center of Mass may be located outside the particle if the particle is not convex.
	Orientation is the angle of the line passing through the particle center of mass with the lowest moment of inertia.
	Dimensions indicates the width and height of Bounding Rect.

Particle Reports (Real-World) is an array that returns a set of calibrated real-world measurements from the detected particles. If the image has no calibration information, uncalibrated pixel measurements are returned. This cluster contains the following elements:

	Area is the area of the particle.
	Number of Holes is the number of holes in the particle. NI Vision can detect holes inside a particle as small as one pixel.
	Bounding Rect is the smallest rectangle with sides parallel to the x-axis and y-axis that completely encloses the particle.
	Center of Mass is the point representing the average position of the total mass of the particle assuming every point in the particle has a constant density. Center of Mass may be located outside the particle if the particle is not convex.
	Orientation is the angle of the line passing through the particle center of mass with the lowest moment of inertia.
	Dimensions indicates the width and height of Bounding Rect.

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.

Calibration Valid indicates whether the calibration information for a particle is valid. Calibration Valid has one Boolean for each report in Particle Reports (Real-World). If the calibration information is invalid for any pixel in the particle, the corresponding Calibration Valid Boolean is FALSE.

Note A pixel has invalid calibration information when the pixel lies outside the area of the image that was calibrated.

Note Particle Report (Real-World) contains measurements for every particle regardless of whether the particle has valid or invalid calibration information.

Examples

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

LabVIEW\examples\Vision\2. Functions\Binary Analysis\Particle Analysis Report Example.vi

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