hough_circle_transhough_circle_transHoughCircleTransHoughCircleTrans (Operator)

Name

hough_circle_transhough_circle_transHoughCircleTransHoughCircleTrans — Return the Hough-Transform for circles with a given radius.

Signature

hough_circle_trans(Region : HoughImage : Radius : )

Description

The operator hough_circle_transhough_circle_transHoughCircleTransHoughCircleTransHoughCircleTrans calculates the Hough transform for circles with a certain RadiusRadiusRadiusRadiusradius in the regions passed by RegionRegionRegionRegionregion. Hereby the centres of all possible circles in the parameter space (the Hough or accumulator space respectively) will be accumulated for each point in the image space. Circle hypotheses supported by many points in the input region thereby generate a maximum in the area showing the circle's centre in the output image (HoughImageHoughImageHoughImageHoughImagehoughImage). The circles' centres in the image space can be deduced from the coordinates of these maximums by subtracting the RadiusRadiusRadiusRadiusradius. If more than one radius is transmitted, all Hough images will be shifted according to the maximal radius.

Execution Information

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

Parameters

RegionRegionRegionRegionregion (input_object) region → object

Binary edge image in which the circles are to be detected.

HoughImageHoughImageHoughImageHoughImagehoughImage (output_object) image(-array) → object (int2)

Hough transform for circles with a given radius.

Number of elements: HoughImage == Radius

RadiusRadiusRadiusRadiusradius (input_control) integer(-array) → (integer)

Radius of the circle to be searched in the image.

Number of elements: 1 <= Radius <= 500

Default value: 12

Typical range of values: 3 ≤ Radius Radius Radius Radius radius (lin)

Minimum increment: 1

Recommended increment: 1

Result

The operator hough_circle_transhough_circle_transHoughCircleTransHoughCircleTransHoughCircleTrans 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>)SetSystem("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>)SetSystem("empty_region_result",<Result>). If necessary an exception is raised.

Module

Foundation