IMAQ LineProfile VI

LabView NI Vision

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IMAQ LineProfile VI

Owning Palette: AnalysisInstalled With: NI Vision Development Module

Calculates the profile of a line of pixels. This VI returns a data type (cluster) compatible with a LabVIEW graph. The relevant pixel information is taken from the specified vector (line).

Examples

IMAQ LineProfile

Image is a reference to the source image.

Line Coordinates is an array specifying the pixel coordinates that form the end points of the line.

Note A line with the coordinates (0, 0, 0, 255) is formed from 256 pixels. Any pixels designated by Line Coordinates that lie outside the actual image are set to 0 in Pixels Line.

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.

Line Graph is a cluster that contains the line 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 line profile calculated in an array in which elements represent the pixel values belonging to the specified vector.

Line Information is a cluster containing relevant information about the pixels found in the specified vector. This cluster contains the following elements:

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

Global Rectangle is a cluster that contains the coordinates of a bounding rectangle for the line 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.

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\Analysis\LineProfile Example.vi

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