MatchGeometricPatternAdvancedOptions2

NI Vision for LabWindows/CVI Function

MatchGeometricPatternAdvancedOptions2

Specifies advanced behaviors of imaqMatchGeometricPattern2(), which can be used to optimize the performance of the function or to fine-tune the matches located by the function.

Elements

Name

Type

Description

minFeaturesUsed int Specifies the minimum number of features the function uses when matching.
maxFeaturesUsed int Specifies the maximum number of features the function uses when matching. Set this element to 0 to specify that the function should use all features.
subpixelIterations int Specifies the maximum number of incremental improvements used to refine matches with subpixel information.
subpixelTolerance double Specifies the maximum amount of change, in pixels, between consecutive incremental improvements in the match position before the function stops refining the match position. Set this element to 0 to specify that the function should always use a number of refinements equal to subpixelIterations. If you provide values for both subpixelIterations and subpixelTolerance, the function refines the match for, at most, subpixelIterations but may stop early if subpixelTolerance is satisfied. If you set subpixelTolerance, the function may invalidate matches during the subpixel refinement process. However, using subpixelIterations alone cannot invalidate a match.
initialMatchListLength int Specifies the maximum size of the match list. The match list contains the regions in the inspection image that have the highest probability of containing a match.
matchTemplateCurveScore float The accuracy of the match obtained by comparing the curves in the match region to the template curves. A score of 1,000 indicates a perfect match, and a score of 0 indicates no match. This element is calculated only if the matchTemplateCurveScore element of the advancedMatchOptions parameter to imaqMatchGeometricPattern() is TRUE.
correlationScore int Set this element to TRUE to specify that the function should calculate the correlation score and return it for each match result. Set this parameter to FALSE to specify that the function should not calculate the correlation score.
minMatchSeparationDistance double Specifies the minimum separation distance, in pixels, between the origins of two matches that have unique positions. The function does not return matches that have the same position, scale, and angle. Set this value to –1 if you do not want the function to use the position of a match to determine whether the match is unique.
minMatchSeparationAngle double Specifies the minimum angular difference, in degrees, between two matches that have unique angles. The function does not return matches that have the same position, scale, and angle. Set this value to –1 if you do not want the function to use the angle of a match to determine whether the match is unique.
minMatchSeparationScale double Specifies the minimum difference in scale, expressed as a percentage, between two matches that have unique scales. The function does not return matches that have the same position, scale, and angle. Set this value to –1 if you do not want the function to use the scale of a match to determine whether the match is unique.
maxMatchOverlap double Specifies the maximum amount of overlap, expressed as a percentage, allowed between the bounding rectangles of two unique matches. The function does not return matches that exceed this overlap percentage. Set this value to –1 if you want the function to ignore bounding rectangle overlap.
coarseResult int Specifies whether you want the function to spend less time accurately estimating the location of a match. Set this value to TRUE if you want to quickly determine whether a part is present in the inspection image without an accurate estimate of its position, angle, and scale. Set this value to FALSE to specify that the function returns matches with pixel or subpixel accuracy.
smoothContours int Set this element to TRUE to specify smoothing be done on the contours of the inspection image before feature extraction.
enableCalibrationSupport int Set this element to TRUE to specify the algorithm treat the inspection image as a calibrated image. Use imaqSetSimpleCalibration() or imaqSetCalibrationInfo() to calibrate the inspection image.