| Operators |
gen_contours_skeleton_xld — Convert a skeleton into XLD contours.
gen_contours_skeleton_xld converts the input skeleton (e.g., edges) Skeleton, which is assumed to contain mostly one pixel wide regions (see skeleton), into XLD contours.
The algorithm first attempts to transform the regions to contain only line segments in 8-neighborhood. In a second step, the junction points are labeled. After this, gen_contours_skeleton_xld tries to generate contours which end in junction or end points, in particular for junction points of the following configurations (in all four possible rotations):
1 0 1 1 0 1 1 0 0 1 0 0 0 1 0 0 1 0 0 2 0 0 2 0 0 2 1 0 2 1 0 2 1 1 2 1 0 0 1 1 0 1 0 1 0 1 0 0 0 1 0 0 1 0where 0 = background, 1 = foreground, and 2 = junction point.
After this, all contours having at least Length points are returned. Since contours are split at junction points, possibly long contours may be split into several short segments because of short adjacent lines, even if they are longer than Length points, if Mode = 'filter' was selected. This can be avoided by setting Mode = 'generalize1'. In this case, the contours are generated as if the segments shorter than Length were not contained in the input region. In order to preserve line segments, which are split into very short segments by the crossing of short lines, Mode = 'generalize2' can be selected. In this case, line segments are preserved if they end in two junction points, even if they are shorter than Length.
Skeleton of which the contours are to be determined.
Resulting contours.
Minimum number of points a contour has to have.
Default value: 1
Suggested values: 1, 2, 3, 5, 10, 20
Contour filter mode.
Default value: 'filter'
List of values: 'filter', 'generalize1', 'generalize2'
smooth_contours_xld, get_contour_xld, gen_polygons_xld
edges_image, threshold, get_region_contour
Foundation
| Operators |