create_distance_transform_xld — Create the XLD distance transform.
create_distance_transform_xld creates the XLD distance transform
of the reference contour
Contour and returns the resulting handle
Once the XLD distance transform has been created, the operator
apply_distance_transform_xld calculates pointwise distances
from test contours to the reference contour
precisely, for each point of a test contour its minimal distance to the
Contour is calculated.
Mode determines which distances
'point_to_point' calculates the minimum distance to the base
points of the
In contrast, 'point_to_segment' calculates the minimum
distance to the contour segments in
Contour (see the figure
MaxDistance specifies a maximum distance from the
Contour which is of interest to the caller.
If the distance from a point of a test contour to the reference contour
MaxDistance, the output distance of
apply_distance_transform_xld is set to
apply_distance_transform_xld are an alternative to
distance_contours_xld, if the reference contour is repeatedly used.
create_distance_transform_xld stores for each pixel in a relevant
Contour its nearest points or segments (depending on
Mode) of the reference contour
Contour. This allows
apply_distance_transform_xld to calculate the distances rather fast,
nearly independent of the number of points or segments of the reference
Mode and the position of the points of the test contour.
However, the preparation of the XLD distance transform can take several
seconds or minutes, depending on the number of points or segments of the
reference contour and the relevant area around
Contour which can
be influenced by
create_distance_transform_xld is faster, if
Mode is set to
get_distance_transform_xld_param can be used to get back the
reference contours and the parameters of the XLD distance
This operator returns a handle. Note that the state of an instance of this handle type may be changed by specific operators even though the handle is used as an input parameter by those operators.
Compute the distance to points ('point_to_point') or entire segments ('point_to_segment').
Default value: 'point_to_point'
List of values: 'point_to_point', 'point_to_segment'
→(real / integer)
Maximum distance of interest.
Default value: 20.0
Handle of the XLD distance transform.
If all parameters are correct, the operator returns the value 2 (H_MSG_TRUE). Otherwise, an exception is raised.