fuzzy_measure_pairsT_fuzzy_measure_pairsFuzzyMeasurePairsfuzzy_measure_pairsFuzzyMeasurePairsFuzzyMeasurePairs (Operator)

Name

fuzzy_measure_pairsT_fuzzy_measure_pairsFuzzyMeasurePairsfuzzy_measure_pairsFuzzyMeasurePairsFuzzyMeasurePairs — Extract straight edge pairs perpendicular to a rectangle or an annular arc.

Signature

Description

fuzzy_measure_pairsfuzzy_measure_pairsFuzzyMeasurePairsfuzzy_measure_pairsFuzzyMeasurePairsFuzzyMeasurePairs serves to extract straight edge pairs which lie perpendicular to the major axis of a rectangle or an annular arc. In addition to measure_pairsmeasure_pairsMeasurePairsmeasure_pairsMeasurePairsMeasurePairs it uses fuzzy functions to evaluate and select the edge pairs.

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

The extraction algorithm of fuzzy_measure_pairsfuzzy_measure_pairsFuzzyMeasurePairsfuzzy_measure_pairsFuzzyMeasurePairsFuzzyMeasurePairs is identical to fuzzy_measure_posfuzzy_measure_posFuzzyMeasurePosfuzzy_measure_posFuzzyMeasurePosFuzzyMeasurePos. In addition, neighboring edges are grouped to pairs. To extract pairs that intersect or include each other, use fuzzy_measure_pairingfuzzy_measure_pairingFuzzyMeasurePairingfuzzy_measure_pairingFuzzyMeasurePairingFuzzyMeasurePairing.

If TransitionTransitionTransitionTransitionTransitiontransition = 'positive'"positive""positive""positive""positive""positive", the edge points with a dark-to-light transition in the direction of the major axis of the rectangle or annular arc are returned in RowEdgeFirstRowEdgeFirstRowEdgeFirstRowEdgeFirstRowEdgeFirstrowEdgeFirst and ColumnEdgeFirstColumnEdgeFirstColumnEdgeFirstColumnEdgeFirstColumnEdgeFirstcolumnEdgeFirst. In this case, the corresponding edges with a light-to-dark transition are returned in RowEdgeSecondRowEdgeSecondRowEdgeSecondRowEdgeSecondRowEdgeSecondrowEdgeSecond and ColumnEdgeSecondColumnEdgeSecondColumnEdgeSecondColumnEdgeSecondColumnEdgeSecondcolumnEdgeSecond. If TransitionTransitionTransitionTransitionTransitiontransition = 'negative'"negative""negative""negative""negative""negative", the behavior is exactly opposite. If TransitionTransitionTransitionTransitionTransitiontransition = 'all'"all""all""all""all""all", the first detected edge defines the transition for RowEdgeFirstRowEdgeFirstRowEdgeFirstRowEdgeFirstRowEdgeFirstrowEdgeFirst and ColumnEdgeFirstColumnEdgeFirstColumnEdgeFirstColumnEdgeFirstColumnEdgeFirstcolumnEdgeFirst. I.e., dependent on the positioning of the measure object, edge pairs with a light-dark-light transition or edge pairs with a dark-light-dark transition are returned. This is suited, e.g., to measure objects with different brightness relative to the background.

Having extracted subpixel edge locations, the edges are paired. The pairing algorithm groups the edges such that interleavings and inclusions of pairs are prohibited. The features of an edge pair are evaluated by a fuzzy function, which can be set by set_fuzzy_measureset_fuzzy_measureSetFuzzyMeasureset_fuzzy_measureSetFuzzyMeasureSetFuzzyMeasure or set_fuzzy_measure_norm_pairset_fuzzy_measure_norm_pairSetFuzzyMeasureNormPairset_fuzzy_measure_norm_pairSetFuzzyMeasureNormPairSetFuzzyMeasureNormPair. Which edge pairs are selected can be determined with the parameter FuzzyThreshFuzzyThreshFuzzyThreshFuzzyThreshFuzzyThreshfuzzyThresh, which constitutes a threshold on the weight over all fuzzy sets, i.e., the geometric mean of the weights of the defined fuzzy functions.

The selected edges are returned as single points, which lie on the major axis of the rectangle or annular arc. The corresponding edge amplitudes are returned in AmplitudeFirstAmplitudeFirstAmplitudeFirstAmplitudeFirstAmplitudeFirstamplitudeFirst and AmplitudeSecondAmplitudeSecondAmplitudeSecondAmplitudeSecondAmplitudeSecondamplitudeSecond, the fuzzy scores in FuzzyScoreFuzzyScoreFuzzyScoreFuzzyScoreFuzzyScorefuzzyScore. In addition, the distance between each edge pair is returned in IntraDistanceIntraDistanceIntraDistanceIntraDistanceIntraDistanceintraDistance and the distance between consecutive edge pairs is returned in InterDistanceInterDistanceInterDistanceInterDistanceInterDistanceinterDistance. Here, IntraDistance[i] corresponds to the distance between EdgeFirst[i] and EdgeSecond[i], while InterDistance[i] corresponds to the distance between EdgeSecond[i] and EdgeFirst[i+1], i.e., the tuple InterDistanceInterDistanceInterDistanceInterDistanceInterDistanceinterDistance contains one element less than the tuples of the edge pairs.

Attention

fuzzy_measure_pairsfuzzy_measure_pairsFuzzyMeasurePairsfuzzy_measure_pairsFuzzyMeasurePairsFuzzyMeasurePairs only returns meaningful results if the assumptions that the edges are straight and perpendicular to the major axis of the rectangle or annular arc are fulfilled. Thus, it should not be used to extract edges from curved objects, for example. Furthermore, the user should ensure that the rectangle or a annular arc is as close to perpendicular as possible to the edges in the image. Additionally, SigmaSigmaSigmaSigmaSigmasigma must not become larger than approx. 0.5 * Length1 (for Length1 see gen_measure_rectangle2gen_measure_rectangle2GenMeasureRectangle2gen_measure_rectangle2GenMeasureRectangle2GenMeasureRectangle2).

It should be kept in mind that fuzzy_measure_pairsfuzzy_measure_pairsFuzzyMeasurePairsfuzzy_measure_pairsFuzzyMeasurePairsFuzzyMeasurePairs ignores the domain of ImageImageImageImageImageimage 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.

Parallelization

• Multithreading type: reentrant (runs in parallel with non-exclusive operators).
• Multithreading scope: global (may be called from any thread).
• Processed without parallelization.

Parameters

Result

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

Possible Predecessors

gen_measure_rectangle2gen_measure_rectangle2GenMeasureRectangle2gen_measure_rectangle2GenMeasureRectangle2GenMeasureRectangle2, gen_measure_arcgen_measure_arcGenMeasureArcgen_measure_arcGenMeasureArcGenMeasureArc, set_fuzzy_measureset_fuzzy_measureSetFuzzyMeasureset_fuzzy_measureSetFuzzyMeasureSetFuzzyMeasure

Possible Successors

close_measureclose_measureCloseMeasureclose_measureCloseMeasureCloseMeasure

Alternatives

edges_sub_pixedges_sub_pixEdgesSubPixedges_sub_pixEdgesSubPixEdgesSubPix, fuzzy_measure_pairingfuzzy_measure_pairingFuzzyMeasurePairingfuzzy_measure_pairingFuzzyMeasurePairingFuzzyMeasurePairing, measure_pairsmeasure_pairsMeasurePairsmeasure_pairsMeasurePairsMeasurePairs

See also

fuzzy_measure_posfuzzy_measure_posFuzzyMeasurePosfuzzy_measure_posFuzzyMeasurePosFuzzyMeasurePos, measure_posmeasure_posMeasurePosmeasure_posMeasurePosMeasurePos

Module

1D Metrology