inner_circleinner_circleInnerCircleInnerCircleinner_circle (Operator)
Name
inner_circleinner_circleInnerCircleInnerCircleinner_circle — Largest inner circle of a region.
Signature
def inner_circle(regions: HObject) -> Tuple[Sequence[float], Sequence[float], Sequence[float]]
def inner_circle_s(regions: HObject) -> Tuple[float, float, float]
Description
The operator inner_circleinner_circleInnerCircleInnerCircleinner_circle determines the largest inner circle
of a region.
This is the biggest discrete circle region that completely fits into
the region.
For this circle the center (RowRowRowrowrow, ColumnColumnColumncolumncolumn) and the
radius (RadiusRadiusRadiusradiusradius) are calculated.
If the position of the circle is ambiguous, the "first possible"
position (as far upper left as possible) is returned.
In the documentation of this chapter (Regions / Features), you can
find an image illustrating regions with varying inner circles.
The output of the operator is chosen in such a way that it can be
used as an input for the operators disp_circledisp_circleDispCircleDispCircledisp_circle,
gen_circlegen_circleGenCircleGenCirclegen_circle, and gen_ellipse_contour_xldgen_ellipse_contour_xldGenEllipseContourXldGenEllipseContourXldgen_ellipse_contour_xld.
If several regions are passed in RegionsRegionsRegionsregionsregions corresponding tuples
are returned as output parameters.
In case of an empty input region all parameters have the value
0.0 if no other behavior was set with set_systemset_systemSetSystemSetSystemset_system.
Attention
If several inner circles are present at a region
only the most upper left solution is returned.
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
RegionsRegionsRegionsregionsregions (input_object) region(-array) → objectHRegionHObjectHObjectHobject
Regions to be examined.
RowRowRowrowrow (output_control) circle.center.y(-array) → HTupleSequence[float]HTupleHtuple (real) (double) (double) (double)
Line index of the center.
ColumnColumnColumncolumncolumn (output_control) circle.center.x(-array) → HTupleSequence[float]HTupleHtuple (real) (double) (double) (double)
Column index of the center.
RadiusRadiusRadiusradiusradius (output_control) circle.radius(-array) → HTupleSequence[float]HTupleHtuple (real) (double) (double) (double)
Radius of the inner circle.
Assertion:
Radius >= 0
Example (HDevelop)
read_image(Image,'fabrik')
regiongrowing(Image,Seg,5,5,6,100)
select_shape(Seg,H,'area','and',100,2000)
inner_circle(H,Row,Column,Radius)
gen_circle(Circles,Row,Column,Radius)
dev_set_draw('margin')
dev_display(Circles)
Example (C)
read_image(&Image,"fabrik");
regiongrowing(Image,&Seg,5,5,6.0,100);
select_shape(Seg,&H,"area","and",100.0,2000.0);
T_inner_circle(H,&Row,&Column,&Radius);
T_gen_circle(&Circles,Row,Column,Radius);
Example (C++)
#include "HIOStream.h"
#if !defined(USE_IOSTREAM_H)
using namespace std;
#endif
#include "HalconCpp.h"
using namespace Halcon;
int main (int argc, char *argv[])
{
Tuple row, col, rad;
HImage img (argv[1]);
HWindow w;
img.Display (w);
HRegionArray reg = img.Regiongrowing (5, 5, 6.0, 100);
HRegionArray seg = reg.SelectShape ("area", "and", 100.0, 1000.0);
row = seg.InnerCircle (&col, &rad);
HRegionArray circ = HRegionArray::GenCircle (row, col, rad);
w.SetDraw ("margin");
w.SetColor ("green"); reg.Display (w);
w.SetColor ("blue"); seg.Display (w);
w.SetColor ("red"); circ.Display (w);
w.Click ();
return(0);
}
Example (HDevelop)
read_image(Image,'fabrik')
regiongrowing(Image,Seg,5,5,6,100)
select_shape(Seg,H,'area','and',100,2000)
inner_circle(H,Row,Column,Radius)
gen_circle(Circles,Row,Column,Radius)
dev_set_draw('margin')
dev_display(Circles)
Complexity
If F is the area of the region and R is the radius of the
inner circle the runtime complexity is O(sqrt(F) * R).
Result
The operator inner_circleinner_circleInnerCircleInnerCircleinner_circle returns the value 2 (
H_MSG_TRUE)
if the input is not empty.
The behavior in case of empty input (no input regions 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>)set_system("no_object_result",<Result>),
the behavior in case of empty region is set via
set_system('empty_region_result',<Result>)set_system("empty_region_result",<Result>)SetSystem("empty_region_result",<Result>)SetSystem("empty_region_result",<Result>)set_system("empty_region_result",<Result>).
If necessary an exception is raised.
Possible Predecessors
thresholdthresholdThresholdThresholdthreshold,
regiongrowingregiongrowingRegiongrowingRegiongrowingregiongrowing,
connectionconnectionConnectionConnectionconnection,
runlength_featuresrunlength_featuresRunlengthFeaturesRunlengthFeaturesrunlength_features
Possible Successors
gen_circlegen_circleGenCircleGenCirclegen_circle,
disp_circledisp_circleDispCircleDispCircledisp_circle
Alternatives
erosion_circleerosion_circleErosionCircleErosionCircleerosion_circle,
inner_rectangle1inner_rectangle1InnerRectangle1InnerRectangle1inner_rectangle1
See also
set_shapeset_shapeSetShapeSetShapeset_shape,
select_shapeselect_shapeSelectShapeSelectShapeselect_shape,
smallest_circlesmallest_circleSmallestCircleSmallestCirclesmallest_circle
Module
Foundation