IMAQ Match Geometric Pattern 2 VI

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Updated2023-02-21
10 minute(s) read

Owning Palette: Searching and Matching
Requires: NI Vision Development Module

Searches for a pattern, or template image, in the inspection image.

Details Examples

Supported Image Types

8-bit unsigned grayscale

IMAQ Match Geometric Pattern 2

ROI Descriptor specifies the region of the inspection image in which to perform geometric matching. This region must be a single rectangle or rotated rectangle contour. By default, the VI uses the entire inspection image for matching.

Global Rectangle contains the coordinates of the bounding rectangle.

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.

Image is a reference to the inspection image in which you want to search for the template image.

Template Image is a reference to the geometric template for which you want to search during the matching phase. The template image is an output of the IMAQ Learn Geometric Pattern 2 VI.

Match Geometric Pattern 2 Setup Data is a string that contains information from the IMAQ Setup Match Geometric Pattern 2 or the IMAQ Advanced Setup Match Geometric Pattern 2 VI. If this input is not connected, the VI uses default parameters for all unconfigured options.

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 Matches Requested is the number of valid matches expected.

Minimum Match Score is the smallest score a match can have to be considered valid. The data range for a match is between 0 and 1000.

Matches (pixel) contains information about a match found in the image.

Position is a point-coordinate cluster corresponding to the location of the template origin.

Angle is the rotation angle, in degrees, of the template at the current match location.

Scale is the ratio of the size of the matched template relative to the original template image, expressed as a percentage.

Score ranks the match results on a scale of 0 to 1000, where 0 equals no match and 1000 equals a perfect match.

Bounding Box is an array of five points that define the boundary of the template.

Contrast Reversed specifies whether the match is an inverse of the template image. This parameter is TRUE if the match is an inverse of the template image. For example, the match is a white object on a black background but the template image is a black object on a white background. This parameter is FALSE if the match is not the inverse of the template image.

Occlusion % is the percentage of the match that is occluded.

Template Target Curve Score specifies how closely the curves in the match region of the inspection, or target, image match the curves in the template. Score values can range from 0 to 1000, where a score of 1000 indicates that all template curves have a corresponding curve in the match region of the inspection image.

Note The VI does not compute the Target Template Curve Score by default. Use the IMAQ Advanced Setup Match Geometric Pattern 2 VI to configure the algorithm to compute this value.

Target Template Curve Score specifies how closely the curves in the match region of the inspection, or target, image match the curves in the template. Score values can range from 0 to 1000, where a score of 1000 indicates that all curves in the match region of the inspection image have a corresponding curve in the template image.

Note The VI does not compute the Target Template Curve Score by default. Use the IMAQ Advanced Setup Match Geometric Pattern VI to configure the algorithm to compute this value.

Correlation Score specifies the accuracy of the match obtained by comparing the template image to the match region using a correlation metric that compares the two regions as a function of their pixel values. A score of 1000 indicates a perfect match, and a score of 0 indicates no match.

Matches (real-world) contains information about a match found in the image.

Note Matches (real-world) may differ from Matches (pixel) if Image is a calibrated image. If Image is a calibrated image, Position, Angle, and Bounding Box are returned in real-world units.