hough_circles ( RegionIn : RegionOut : Radius, Percent, Mode : )

Centres of circles for a specific radius.

hough_circle_trans detects the centres of circles in regions with the help of the Hough transform for circles with a specific radius.


Parameters

RegionIn (input_object)
region -> object
Binary edge image in which the circles are to be detected.

RegionOut (output_object)
region(-array) -> object
Centres of those circles which are included in the edge image by Percent percent.
Number of elements: RegionOut == ((Radius * Percent) * Mode)

Radius (input_control)
integer(-array) -> integer
Radius of the circle to be searched in the image.
Default value: 12
Typical range of values: 2 <= Radius <= 500 (lin)
Minimum increment: 1
Recommended increment: 1
Number of elements: (1 <= Radius) <= 500

Percent (input_control)
integer(-array) -> integer
Indicates the percentage (approximately) of the (ideal) circle which must be present in the edge image RegionIn.
Default value: 60
Typical range of values: 10 <= Percent <= 100 (lin)
Minimum increment: 1
Recommended increment: 5
Number of elements: (1 <= Percent) <= 100

Mode (input_control)
integer(-array) -> integer
The modus defines the position of the circle in question:

0 - the radius is equivalent to the outer border of the set pixels.

1 - the radius is equivalent to the centres of the circle lines´ pixels.

2 - both 0 and 1 (a little more fuzzy, but more reliable in contrast to circles set slightly differently, necessitates 50 % more processing capacity compared to 0 or 1 alone).

List of values: 0, 1, 2
Number of elements: (1 <= Mode) <= 3


Result

The operator hough_circles 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>), the behavior in case of empty region is set via set_system('empty_region_result',<Result>). If necessary an exception handling is raised.


Parallelization Information

hough_circles is reentrant and processed without parallelization.


Module

Region processing



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