distance_rr_mindistance_rr_minDistanceRrMinDistanceRrMin (Operator)

Name

distance_rr_mindistance_rr_minDistanceRrMinDistanceRrMin — Minimum distance between the contour pixels of two regions each.

Signature

distance_rr_min(Regions1, Regions2 : : : MinDistance, Row1, Column1, Row2, Column2)

Description

The operator distance_rr_mindistance_rr_minDistanceRrMinDistanceRrMinDistanceRrMin calculates the minimum distance of pairs of regions. If several regions are passed in Regions1Regions1Regions1Regions1regions1 and Regions2Regions2Regions2Regions2regions2 the distance between the contour pixels of each i-th element is calculated and then forms the i-th entry in the output parameter MinDistanceMinDistanceMinDistanceMinDistanceminDistance. The Euclidean distance is used. The parameters (Row1Row1Row1Row1row1, Column1Column1Column1Column1column1) and (Row2Row2Row2Row2row2, Column2Column2Column2Column2column2) indicate the position on the contour of Regions1Regions1Regions1Regions1regions1 and Regions2Regions2Regions2Regions2regions2, respectively, that have the minimum distance.

The calculation is carried out by comparing all contour pixels (see get_region_contourget_region_contourGetRegionContourGetRegionContourGetRegionContour). This means in particular that holes in the regions are ignored. Furthermore, it is not checked whether one region lies completely within the other region. In this case, a minimum distance > 0 is returned. It is also not checked whether both regions contain a nonempty intersection. In the latter case, a minimum distance of 0 or > 0 can be returned, depending on whether the contours of the regions contain a common point or not.

Attention

Both input parameters must contain the same number of regions. The regions must not be empty.

Execution Information

Multithreading type: reentrant (runs in parallel with non-exclusive operators).
Multithreading scope: global (may be called from any thread).
Automatically parallelized on tuple level.

Parameters

Regions1Regions1Regions1Regions1regions1 (input_object) region(-array) → object

Regions to be examined.

Regions2Regions2Regions2Regions2regions2 (input_object) region(-array) → object

Regions to be examined.

MinDistanceMinDistanceMinDistanceMinDistanceminDistance (output_control) real(-array) → (real)

Minimum distance between contours of the regions.

Assertion: 0 <= MinDistance

Row1Row1Row1Row1row1 (output_control) point.y(-array) → (integer)

Line index on contour in Regions1Regions1Regions1Regions1regions1.

Column1Column1Column1Column1column1 (output_control) point.x(-array) → (integer)

Column index on contour in Regions1Regions1Regions1Regions1regions1.

Row2Row2Row2Row2row2 (output_control) point.y(-array) → (integer)

Line index on contour in Regions2Regions2Regions2Regions2regions2.

Column2Column2Column2Column2column2 (output_control) point.x(-array) → (integer)

Column index on contour in Regions2Regions2Regions2Regions2regions2.

Complexity

If N1,N2 are the lengths of the contours the runtime complexity is O(N1 * N2).

Result

The operator distance_rr_mindistance_rr_minDistanceRrMinDistanceRrMinDistanceRrMin returns the value 2 (H_MSG_TRUE) if the input is not empty. Otherwise an exception is raised.

Possible Predecessors

thresholdthresholdThresholdThresholdThreshold, regiongrowingregiongrowingRegiongrowingRegiongrowingRegiongrowing, connectionconnectionConnectionConnectionConnection

Alternatives

distance_rr_min_dildistance_rr_min_dilDistanceRrMinDilDistanceRrMinDilDistanceRrMinDil, dilation1dilation1Dilation1Dilation1Dilation1, intersectionintersectionIntersectionIntersectionIntersection

Module

Foundation

Operators