ClassesClasses | | Operators

fuzzy_measure_posT_fuzzy_measure_posFuzzyMeasurePosFuzzyMeasurePos (Operator)

Name

fuzzy_measure_posT_fuzzy_measure_posFuzzyMeasurePosFuzzyMeasurePos — Extract straight edges perpendicular to a rectangle or an annular arc.

Signature

fuzzy_measure_pos(Image : : MeasureHandle, Sigma, AmpThresh, FuzzyThresh, Transition : RowEdge, ColumnEdge, Amplitude, FuzzyScore, Distance)

Herror T_fuzzy_measure_pos(const Hobject Image, const Htuple MeasureHandle, const Htuple Sigma, const Htuple AmpThresh, const Htuple FuzzyThresh, const Htuple Transition, Htuple* RowEdge, Htuple* ColumnEdge, Htuple* Amplitude, Htuple* FuzzyScore, Htuple* Distance)

void FuzzyMeasurePos(const HObject& Image, const HTuple& MeasureHandle, const HTuple& Sigma, const HTuple& AmpThresh, const HTuple& FuzzyThresh, const HTuple& Transition, HTuple* RowEdge, HTuple* ColumnEdge, HTuple* Amplitude, HTuple* FuzzyScore, HTuple* Distance)

void HMeasure::FuzzyMeasurePos(const HImage& Image, double Sigma, double AmpThresh, double FuzzyThresh, const HString& Transition, HTuple* RowEdge, HTuple* ColumnEdge, HTuple* Amplitude, HTuple* FuzzyScore, HTuple* Distance) const

void HMeasure::FuzzyMeasurePos(const HImage& Image, double Sigma, double AmpThresh, double FuzzyThresh, const char* Transition, HTuple* RowEdge, HTuple* ColumnEdge, HTuple* Amplitude, HTuple* FuzzyScore, HTuple* Distance) const

void HImage::FuzzyMeasurePos(const HMeasure& MeasureHandle, double Sigma, double AmpThresh, double FuzzyThresh, const HString& Transition, HTuple* RowEdge, HTuple* ColumnEdge, HTuple* Amplitude, HTuple* FuzzyScore, HTuple* Distance) const

void HImage::FuzzyMeasurePos(const HMeasure& MeasureHandle, double Sigma, double AmpThresh, double FuzzyThresh, const char* Transition, HTuple* RowEdge, HTuple* ColumnEdge, HTuple* Amplitude, HTuple* FuzzyScore, HTuple* Distance) const

static void HOperatorSet.FuzzyMeasurePos(HObject image, HTuple measureHandle, HTuple sigma, HTuple ampThresh, HTuple fuzzyThresh, HTuple transition, out HTuple rowEdge, out HTuple columnEdge, out HTuple amplitude, out HTuple fuzzyScore, out HTuple distance)

void HMeasure.FuzzyMeasurePos(HImage image, double sigma, double ampThresh, double fuzzyThresh, string transition, out HTuple rowEdge, out HTuple columnEdge, out HTuple amplitude, out HTuple fuzzyScore, out HTuple distance)

void HImage.FuzzyMeasurePos(HMeasure measureHandle, double sigma, double ampThresh, double fuzzyThresh, string transition, out HTuple rowEdge, out HTuple columnEdge, out HTuple amplitude, out HTuple fuzzyScore, out HTuple distance)

Description

fuzzy_measure_posfuzzy_measure_posFuzzyMeasurePosFuzzyMeasurePosFuzzyMeasurePos extracts straight edges which lie perpendicular to the major axis of a rectangle or an annular arc. In addition to measure_posmeasure_posMeasurePosMeasurePosMeasurePos it uses fuzzy functions to evaluate and select the edges.

For an explanation of the concept of 1D measuring see the introduction of chapter 1D Measuring.

The algorithm of fuzzy_measure_posfuzzy_measure_posFuzzyMeasurePosFuzzyMeasurePosFuzzyMeasurePos works by averaging the gray values in “slices” perpendicular to the major axis of the rectangle or annular arc in order to obtain a one-dimensional edge profile. The sampling is done at subpixel positions in the image ImageImageImageImageimage at integer row and column distances (in the coordinate frame of the rectangle) from the center of the rectangle. Since this involves some calculations which can be used repeatedly in several measurements, the operator gen_measure_rectangle2gen_measure_rectangle2GenMeasureRectangle2GenMeasureRectangle2GenMeasureRectangle2 is used to perform these calculations only once, thus increasing the speed of fuzzy_measure_posfuzzy_measure_posFuzzyMeasurePosFuzzyMeasurePosFuzzyMeasurePos significantly. Since there is a trade-off between accuracy and speed in the subpixel calculations of the gray values, and thus in the accuracy of the extracted edge positions, different interpolation schemes can be selected in gen_measure_rectangle2gen_measure_rectangle2GenMeasureRectangle2GenMeasureRectangle2GenMeasureRectangle2. (The interpolation only influences rectangles not aligned with the image axes and annular arcs.) The measure object generated with gen_measure_rectangle2gen_measure_rectangle2GenMeasureRectangle2GenMeasureRectangle2GenMeasureRectangle2 is passed in MeasureHandleMeasureHandleMeasureHandleMeasureHandlemeasureHandle.

After the one-dimensional edge profile has been calculated, subpixel edge locations are computed by convolving the profile with the derivatives of a Gaussian smoothing kernel of standard deviation SigmaSigmaSigmaSigmasigma. Salient edges can be selected with the parameter AmpThreshAmpThreshAmpThreshAmpThreshampThresh, which constitutes a threshold on the amplitude, i.e., the absolute value of the first derivative of the edge. Additionally, it is possible to select only positive edges, i.e., edges which constitute a dark-to-light transition in the direction of the major axis of the rectangle (TransitionTransitionTransitionTransitiontransition = 'positive'"positive""positive""positive""positive"), only negative edges, i.e., light-to-dark transitions (TransitionTransitionTransitionTransitiontransition = 'negative'"negative""negative""negative""negative"), or both types of edges (TransitionTransitionTransitionTransitiontransition = 'all'"all""all""all""all"). Finally, it is possible to select which edge points are returned.

Having extracted subpixel edge locations, features of these edges are evaluated by a corresponding fuzzy function, which can be set by set_fuzzy_measureset_fuzzy_measureSetFuzzyMeasureSetFuzzyMeasureSetFuzzyMeasure. Which edges are selected can be determined with the parameter FuzzyThreshFuzzyThreshFuzzyThreshFuzzyThreshfuzzyThresh, which constitutes a threshold on the weight over all fuzzy sets, i.e., the geometric mean of the weights of the defined sets.

The selected edges are returned as single points, which lie on the major axis of the rectangle or annular arc, in (RowEdgeRowEdgeRowEdgeRowEdgerowEdge,ColumnEdgeColumnEdgeColumnEdgeColumnEdgecolumnEdge). The corresponding edge amplitudes are returned in AmplitudeAmplitudeAmplitudeAmplitudeamplitude, the fuzzy scores in FuzzyScoreFuzzyScoreFuzzyScoreFuzzyScorefuzzyScore. In addition, the distance between consecutive edge points is returned in DistanceDistanceDistanceDistancedistance. Here, Distance[i] corresponds to the distance between Edge[i] and Edge[i+1], i.e., the tuple DistanceDistanceDistanceDistancedistance contains one element less than the tuples RowEdgeRowEdgeRowEdgeRowEdgerowEdge and ColumnEdgeColumnEdgeColumnEdgeColumnEdgecolumnEdge.

Attention

fuzzy_measure_posfuzzy_measure_posFuzzyMeasurePosFuzzyMeasurePosFuzzyMeasurePos only returns meaningful results if the assumptions that the edges are straight and perpendicular to the major axis of the rectangle are fulfilled. Thus, it should not be used to extract edges from curved objects, for example. Furthermore, the user should ensure that the rectangle is as close to perpendicular as possible to the edges in the image. Additionally, SigmaSigmaSigmaSigmasigma must not become larger than approx. 0.5 * Length1 (for Length1 see gen_measure_rectangle2gen_measure_rectangle2GenMeasureRectangle2GenMeasureRectangle2GenMeasureRectangle2).

It should be kept in mind that fuzzy_measure_posfuzzy_measure_posFuzzyMeasurePosFuzzyMeasurePosFuzzyMeasurePos ignores the domain of ImageImageImageImageimage for efficiency reasons. If certain regions in the image should be excluded from the measurement a new measure object with appropriately modified parameters should be generated.

Execution Information

Parameters

ImageImageImageImageimage (input_object)  singlechannelimage objectHImageHImageHobject (byte / uint2 / real)

Input image.

MeasureHandleMeasureHandleMeasureHandleMeasureHandlemeasureHandle (input_control)  measure_id HMeasure, HTupleHTupleHtuple (integer) (IntPtr) (Hlong) (Hlong)

Measure object handle.

SigmaSigmaSigmaSigmasigma (input_control)  number HTupleHTupleHtuple (real) (double) (double) (double)

Sigma of Gaussian smoothing.

Default value: 1.0

Suggested values: 0.4, 0.6, 0.8, 1.0, 1.5, 2.0, 3.0, 4.0, 5.0, 7.0, 10.0

Typical range of values: 0.4 ≤ Sigma Sigma Sigma Sigma sigma ≤ 100 (lin)

Minimum increment: 0.01

Recommended increment: 0.1

Restriction: Sigma >= 0.4

AmpThreshAmpThreshAmpThreshAmpThreshampThresh (input_control)  number HTupleHTupleHtuple (real) (double) (double) (double)

Minimum edge amplitude.

Default value: 30.0

Suggested values: 5.0, 10.0, 20.0, 30.0, 40.0, 50.0, 60.0, 70.0, 90.0, 110.0

Typical range of values: 1 ≤ AmpThresh AmpThresh AmpThresh AmpThresh ampThresh ≤ 255 (lin)

Minimum increment: 0.5

Recommended increment: 2

FuzzyThreshFuzzyThreshFuzzyThreshFuzzyThreshfuzzyThresh (input_control)  number HTupleHTupleHtuple (real) (double) (double) (double)

Minimum fuzzy value.

Default value: 0.5

Suggested values: 0.1, 0.3, 0.5, 0.6, 0.7, 0.9

Typical range of values: 0.0 ≤ FuzzyThresh FuzzyThresh FuzzyThresh FuzzyThresh fuzzyThresh ≤ 1.0 (lin)

Recommended increment: 0.1

TransitionTransitionTransitionTransitiontransition (input_control)  string HTupleHTupleHtuple (string) (string) (HString) (char*)

Select light/dark or dark/light edges.

Default value: 'all' "all" "all" "all" "all"

List of values: 'all'"all""all""all""all", 'negative'"negative""negative""negative""negative", 'positive'"positive""positive""positive""positive"

RowEdgeRowEdgeRowEdgeRowEdgerowEdge (output_control)  point.y-array HTupleHTupleHtuple (real) (double) (double) (double)

Row coordinate of the edge point.

ColumnEdgeColumnEdgeColumnEdgeColumnEdgecolumnEdge (output_control)  point.x-array HTupleHTupleHtuple (real) (double) (double) (double)

Column coordinate of the edge point.

AmplitudeAmplitudeAmplitudeAmplitudeamplitude (output_control)  real-array HTupleHTupleHtuple (real) (double) (double) (double)

Edge amplitude of the edge (with sign).

FuzzyScoreFuzzyScoreFuzzyScoreFuzzyScorefuzzyScore (output_control)  real-array HTupleHTupleHtuple (real) (double) (double) (double)

Fuzzy evaluation of the edges.

DistanceDistanceDistanceDistancedistance (output_control)  real-array HTupleHTupleHtuple (real) (double) (double) (double)

Distance between consecutive edges.

Result

If the parameter values are correct the operator fuzzy_measure_posfuzzy_measure_posFuzzyMeasurePosFuzzyMeasurePosFuzzyMeasurePos returns the value 2 (H_MSG_TRUE). Otherwise an exception is raised.

Possible Predecessors

gen_measure_rectangle2gen_measure_rectangle2GenMeasureRectangle2GenMeasureRectangle2GenMeasureRectangle2, gen_measure_arcgen_measure_arcGenMeasureArcGenMeasureArcGenMeasureArc, set_fuzzy_measureset_fuzzy_measureSetFuzzyMeasureSetFuzzyMeasureSetFuzzyMeasure

Possible Successors

close_measureclose_measureCloseMeasureCloseMeasureCloseMeasure

Alternatives

edges_sub_pixedges_sub_pixEdgesSubPixEdgesSubPixEdgesSubPix, measure_posmeasure_posMeasurePosMeasurePosMeasurePos

See also

fuzzy_measure_pairingfuzzy_measure_pairingFuzzyMeasurePairingFuzzyMeasurePairingFuzzyMeasurePairing, fuzzy_measure_pairsfuzzy_measure_pairsFuzzyMeasurePairsFuzzyMeasurePairsFuzzyMeasurePairs, measure_pairsmeasure_pairsMeasurePairsMeasurePairsMeasurePairs

Module

1D Metrology


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