hough_lines ( RegionIn : : AngleResolution, Threshold, AngleGap, DistGap : Angle, Dist )
Detects lines in edge images with the help of the Hough transform and
returns it in HNF
The operator hough_lines allows the selection of linelike structures in a region,
whereby it is not necessary that the individual points of a line are connected. This process
is based on the Hough transform. The lines are returned in HNF, that is
by the direction and length of their normal vector.
The parameter AngleResolution defines the degree of exactness concerning
the determination of the angles. It amounts to 1 / AngleResolution degree.
The parameter Threshold determines by how many points of the original region a
line's hypothesis has to be supported at least in order to be taken over into the output.
The parameters AngleGap and DistGap define a neighborhood of the
points in the Hough image for in order to determine the local maximums.
The lines are returned in HNF.
Parameters
RegionIn (input_object)
|
region -> object
|
Binary edge image in which the lines are to be detected. |
AngleResolution (input_control)
|
integer -> integer
|
Adjusting the resolution in the angle area. |
Default value: 4 |
List of values: 1, 2, 4, 8 |
Threshold (input_control)
|
integer -> integer
|
Threshold value in the Hough image |
Default value: 100 |
Range of values: 1 <= Threshold |
AngleGap (input_control)
|
integer -> integer
|
Minimal distance of two maximums in the Hough image
(direction: angle) |
Default value: 5 |
Range of values: 0 <= AngleGap |
DistGap (input_control)
|
integer -> integer
|
Minimal distance of two maximums in the Hough image
(direction: distance) |
Default value: 5 |
Range of values: 0 <= DistGap |
Angle (output_control)
|
hesseline.angle.deg-array -> real
|
Angles (in degrees) of the detected lines' normal vectors |
Range of values: -90.0 <= Angle <= 180.0 |
Dist (output_control)
|
hesseline.distance-array -> real
|
Distance of the detected lines from the origin |
Range of values: -90.0 <= Dist <= 180.0 |
Number of elements: Dist == Angle |
Possible Predecessors
threshold__,
skeleton
Possible Successors
matching_lines
See also
hough_line_trans,
store_hesse_lines,
hough_circles
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