connection — Compute connected components of a region.
connection determines the connected components of the input regions given in Region. The neighborhood used for this can be set via set_system('neighborhood',<4/8>). The default is 8-neighborhood, which is useful for determining the connected components of the foreground. The maximum number of connected components that is returned by connection can be set via set_system('max_connection',<Num>). The default value of 0 causes all connected components to be returned. The inverse operator of connection is union1.
read_image(Image,'clip') dev_set_colored(12) threshold(Image,Dark,0,150) count_obj(Dark,NumThresholded) dev_display (Dark) connection(Dark,ConnectedRegions) count_obj(ConnectedRegions,NumConnected) dev_display (ConnectedRegions)
Let F be the area of the input region and N be the number of generated connected components. Then the runtime complexity is O(sqrt(F) * sqrt(N)).
connection always returns the value 2 (H_MSG_TRUE). The behavior in case of empty input (no regions given) can be set via set_system('no_object_result',<Result>) and the behavior in case of an empty input region via set_system('empty_region_result',<Result>). If necessary, an exception is raised.
auto_threshold, threshold, dyn_threshold, erosion1
select_shape, select_gray, shape_trans, set_colored, dilation1, count_obj, reduce_domain, add_channels