IMAQ ROIProfile VI

LabView NI Vision

IMAQ ROIProfile VI

Owning Palette: AnalysisInstalled With: NI Vision Development Module

Calculates the profile of the pixels along the boundary of an ROI descriptor. This VI returns a data type (cluster) that is compatible with a LabVIEW graph. This VI also returns other information such as pixel statistics and the coordinates of the pixels along the ROI boundary.

Examples

IMAQ ROIProfile

Image is a reference to the source image.

ROI Descriptor is a descriptor that defines the region of interest.

Global Rectangle is the minimum rectangle required to contain all of the contours in the ROI.

Contours are each of the individual shapes that define an ROI.

	ID refers to whether the contour is the external or internal edge of an ROI.
	Type is the shape type of the contour.
	Coordinates indicates the relative position of the contour.

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.

ROI Graph is a cluster that contains the ROI profile with an x-origin at 0 and an increment of 1. The cluster contains the following elements:

	x0 always returns 0.
	dx always returns 1.
	Pixels Line returns the ROI profile calculated in an array in which elements represent the pixel values belonging to the specified vector.

Pixel Coordinates is an array containing the spatial coordinates of each pixel along the ROI boundary.

ROI Pixel Statistics is a cluster containing relevant information about the pixels found along the ROI boundary. The cluster contains the following elements:

	Min returns the smallest pixel value found in the ROI profile.
	Max returns the largest pixel value found in the ROI profile.
	Mean returns the mean value of the pixels found in the ROI profile.
	Std Dev returns the standard deviation from the ROI profile.
	Count returns the count of pixels found in the ROI profile.

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.

Global Rectangle is a cluster that contains the coordinates of a bounding rectangle for the ROI in the image. This cluster includes the following parameters:

	x1Left indicates the x-coordinate of the top-left corner of the rectangle.
	y1Top indicates the y-coordinate of the top-left corner of the rectangle.
	x2Right indicates the x-coordinate of the bottom-right corner of the rectangle.
	y2Bottom indicates the y-coordinate of the bottom-right corner of the rectangle.

Examples

Refer to the following for examples that use this VI.

LabVIEW\examples\Vision\2. Functions\Caliper\Edge Detection Example.llb
LabVIEW\examples\Vision\3. Applications\Mechanical Assembly Example.vi

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