compactness_xldcompactness_xldCompactnessXldCompactnessXldcompactness_xld (Operator)
Name
compactness_xldcompactness_xldCompactnessXldCompactnessXldcompactness_xld — Shape factor for the compactness of contours or polygons.
Signature
def compactness_xld(xld: HObject) -> Sequence[float]
def compactness_xld_s(xld: HObject) -> float
Description
The operator compactness_xldcompactness_xldCompactnessXldCompactnessXldCompactnessXldcompactness_xld calculates the compactness of each
input contour or polygon in XLDXLDXLDXLDXLDxld. The input contour or polygon must
not intersect itself, otherwise the resulting parameter is not meaningful
(Whether the input contour or polygon intersects itself or not can be
determined with test_self_intersection_xldtest_self_intersection_xldTestSelfIntersectionXldTestSelfIntersectionXldTestSelfIntersectionXldtest_self_intersection_xld). If
the input contour or polygon is not closed it will be closed automatically.
Calculation:
If L is the length and F the
enclosed area of the contour or polygon the shape
factor CompactnessCompactnessCompactnessCompactnesscompactnesscompactness is defined as:
The shape factor CompactnessCompactnessCompactnessCompactnesscompactnesscompactness of a circle is 1.
If the contour or polygon encloses an elongated area CompactnessCompactnessCompactnessCompactnesscompactnesscompactness
is larger than 1. The operator compactness_xldcompactness_xldCompactnessXldCompactnessXldCompactnessXldcompactness_xld responds to the
course of the contour or polygon (roughness).
If more than one contour or polygon is passed, the shape factors are stored
in a tuple in the same order as the respective contours or polygons in
XLDXLDXLDXLDXLDxld.
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
XLDXLDXLDXLDXLDxld (input_object) xld(-array) → objectHXLDHObjectHXLDHobject
Contours or polygons to be examined.
CompactnessCompactnessCompactnessCompactnesscompactnesscompactness (output_control) real(-array) → HTupleSequence[float]HTupleHtuple (real) (double) (double) (double)
Compactness of the input contours or polygons.
Assertion:
Compactness >= 1.0 || Compactness == 0
Result
The operator compactness_xldcompactness_xldCompactnessXldCompactnessXldCompactnessXldcompactness_xld returns the value 2 (
H_MSG_TRUE)
if the input is not empty.
The behavior in case of empty input (no input contours available) is
set via the operator set_system('no_object_result',<Result>)set_system("no_object_result",<Result>)SetSystem("no_object_result",<Result>)SetSystem("no_object_result",<Result>)SetSystem("no_object_result",<Result>)set_system("no_object_result",<Result>).
If necessary an exception is raised.
Possible Predecessors
gen_contours_skeleton_xldgen_contours_skeleton_xldGenContoursSkeletonXldGenContoursSkeletonXldGenContoursSkeletonXldgen_contours_skeleton_xld,
edges_sub_pixedges_sub_pixEdgesSubPixEdgesSubPixEdgesSubPixedges_sub_pix,
threshold_sub_pixthreshold_sub_pixThresholdSubPixThresholdSubPixThresholdSubPixthreshold_sub_pix,
gen_contour_polygon_xldgen_contour_polygon_xldGenContourPolygonXldGenContourPolygonXldGenContourPolygonXldgen_contour_polygon_xld,
test_self_intersection_xldtest_self_intersection_xldTestSelfIntersectionXldTestSelfIntersectionXldTestSelfIntersectionXldtest_self_intersection_xld
Alternatives
circularity_xldcircularity_xldCircularityXldCircularityXldCircularityXldcircularity_xld,
convexity_xldconvexity_xldConvexityXldConvexityXldConvexityXldconvexity_xld,
eccentricity_xldeccentricity_xldEccentricityXldEccentricityXldEccentricityXldeccentricity_xld,
rectangularity_xldrectangularity_xldRectangularityXldRectangularityXldRectangularityXldrectangularity_xld
See also
area_center_xldarea_center_xldAreaCenterXldAreaCenterXldAreaCenterXldarea_center_xld,
select_shape_xldselect_shape_xldSelectShapeXldSelectShapeXldSelectShapeXldselect_shape_xld
Module
Foundation