Separate overlapping regions.

The opening_seg operation is defined as a sequence of the following operators: erosion1, connection and dilation1 (see example). Only one iteration is done in erosion1 and dilation1.

opening_seg serves to separate overlapping regions whose area of overlap is smaller than StructElement. It should be noted that the resulting regions can overlap without actually merging (see expand_region). opening_seg uses the center of gravity as the reference point of the structuring element.

Structuring elements (StructElement) can be generated with operators such as gen_circle, gen_rectangle1, gen_rectangle2, gen_ellipse, draw_region, gen_region_polygon, gen_region_points, etc.

/* Simulation of opening_seg */
opening_seg(Region,StructElement,RegionOpening):
    erosion1(Region,StructElement,H1,1) >
    connection(H1,H2) 
    dilation1(H2,StructElement,RegionOpening,1) 
    clear_obj([H1,H2]).

Let F1 be the area of the input region, and F2 be the area of the structuring element. Then the runtime complexity for one region is:

    O(sqrt(F1) * sqrt(F2) * sqrt(sqrt(F1)) .

opening_seg returns 2 (H_MSG_TRUE) if all parameters are correct. The behavior in case of empty or no input region can be set via:

  a) no region:    set_system('no_object_result',<RegionResult>)
  b) empty region: set_system('empty_region_result',<RegionResult>)

opening_seg is reentrant and automatically parallelized (on tuple level).

threshold, regiongrowing, connection, union1, watersheds, class_ndim_norm, gen_circle, gen_ellipse, gen_rectangle1, gen_rectangle2, draw_region, gen_region_points, gen_struct_elements, gen_region_polygon_filled

expand_region, reduce_domain, select_shape, area_center, connection

erosion1, connection, dilation1

Foundation