MatchContours

Compare contours using the Hu moment invariants (and optionally further aspects). In case of multiple contours in each container, the best matches are found and the average dissimilarity over all matched contours is returned.

Syntax

Definition:

HRESULT MatchContours(
    HRESULT                            hrPrev,
    ITcVnContainer*                    ipContour1,
    ITcVnContainer*                    ipContour2,
    ETcVnContoursMatchComparisonMethod eComparisonMethod,
    double&                            fDissimilarity,
    double                             fAreaFactor = 0,
    double                             fAbsPositionFactor = 0,
    double                             fRelPositionFactor = 0,
    double                             fNumDiffFactor = 0
)

Parameters

Name	Type	Default	Description
hrPrev	HRESULT		HRESULT indicating the result of previous operations (If SUCCEEDED(hrPrev) equals false, no operation is executed.)
ipContour1	ITcVnContainer*		First contour (ContainerType_Vector_TcVnPoint2_DINT or ContainerType_Vector_TcVnPoint2_REAL; The elements of this container are the points of the contour) or collection of multiple contours (ContainerType_Vector_Vector_TcVnPoint2_DINT)
ipContour2	ITcVnContainer*		Second contour (same type as ipContour1)
eComparisonMethod	ETcVnContoursMatchComparisonMethod		Method used for comparing the Hu moment invariants of the contours
fDissimilarity	double&		Returns the dissimilarity of the contours depending on the chosen comparison method
fAreaFactor	double	0	If > 0, the relative area difference between contours is scaled by this factor and added to the computed dissimilarity
fAbsPositionFactor	double	0	If > 0, the absolute position difference between contours (i.e. the coordinates of the geometric contour centers) is scaled by this factor and added to the computed dissimilarity
fRelPositionFactor	double	0	If > 0, the relative position difference between contours is scaled by this factor and added to the computed dissimilarity (only used if matching multiple contours)
fNumDiffFactor	double	0	If > 0, the difference between the number of contours in both containers is scaled by this factor and added to the computed dissimilarity (only used if matching multiple contours)

Return value

HRESULT

Required License

TC3 Vision Matching

System Requirements

Development environment	Target platform	PLC libraries to include
TwinCAT V3.1. 4024.44 or later	PC or CX (x64) with PL50, e.g. Intel 4-core Atom CPU	Tc3_Vision