[mmsedil] [Up] [mmcdil] Structuring Elements

mmseunion
Union of structuring elements

Synopsis

B = mmseunion( B1, B2 )

Implemented in Python.

Input

B1	Structuring Element
B2	Structuring Element

Output

B	Structuring Element

Description

mmseunion creates a structuring element from the union of two structuring elements.

Examples

>>> b1 = mmseline(5)

>>> mmseshow(b1)

array([0, 0, 0, 0, 1, 1, 1, 1, 1],'1')

>>> b2 = mmsedisk(3)

>>> mmseshow(b2)

array([[0, 0, 1, 1, 1, 0, 0],
       [0, 1, 1, 1, 1, 1, 0],
       [1, 1, 1, 1, 1, 1, 1],
       [1, 1, 1, 1, 1, 1, 1],
       [1, 1, 1, 1, 1, 1, 1],
       [0, 1, 1, 1, 1, 1, 0],
       [0, 0, 1, 1, 1, 0, 0]],'1')

>>> b3 = mmseunion(b1,b2)

>>> mmseshow(b3)

array([[0, 0, 0, 1, 1, 1, 0, 0, 0],
       [0, 0, 1, 1, 1, 1, 1, 0, 0],
       [0, 1, 1, 1, 1, 1, 1, 1, 0],
       [0, 1, 1, 1, 1, 1, 1, 1, 1],
       [0, 1, 1, 1, 1, 1, 1, 1, 0],
       [0, 0, 1, 1, 1, 1, 1, 0, 0],
       [0, 0, 0, 1, 1, 1, 0, 0, 0]],'1')

Equation

Flat structuring element:

Non-flat structuring element:

Source Code
        def mmseunion(B1, B2):
    from Numeric import maximum, ones, asarray, NewAxis
    assert B1.typecode() == B2.typecode(), 'Cannot have different datatypes:'
    type1 = B1.typecode()
    if len(B1) == 0: return B2
    if len(B1.shape) == 1: B1 = B1[NewAxis,:]
    if len(B2.shape) == 1: B2 = B2[NewAxis,:]
    if B1.shape <> B2.shape:
        inf = mmlimits(B1)[0]
        h1,w1 = B1.shape
        h2,w2 = B2.shape
        H,W = max(h1,h2),max(w1,w2)
        Hc,Wc = (H-1)/2,(W-1)/2    # center
        BB1,BB2 = asarray(B1),asarray(B2)
        B1, B2  = inf * ones((H,W)), inf *ones((H,W))
        dh1s , dh1e = (h1-1)/2 , (h1-1)/2 + (h1+1)%2 # deal with even and odd dimensions
        dw1s , dw1e = (w1-1)/2 , (w1-1)/2 + (w1+1)%2
        dh2s , dh2e = (h2-1)/2 , (h2-1)/2 + (h2+1)%2
        dw2s , dw2e = (w2-1)/2 , (w2-1)/2 + (w2+1)%2
        B1[ Hc-dh1s : Hc+dh1e+1  ,  Wc-dw1s : Wc+dw1e+1 ] = BB1
        B2[ Hc-dh2s : Hc+dh2e+1  ,  Wc-dw2s : Wc+dw2e+1 ] = BB2
    B = maximum(B1,B2).astype(type1)
    return B
    
      

mmdil	Dilate an image by a structuring element.
mmseshow	Display a structuring element as an image.
mmero	Erode an image by a structuring element.
mmsesum	N-1 iterative Minkowski additions
mmsetrans	Translate a structuring element

[`mmsedil`] [Up] [`mmcdil`]
Copyright (c) 2003, Roberto A. Lotufo, UNICAMP-University of Campinas; Rubens C. Machado, CenPRA-Renato Archer Research Center.

mmseunion Union of structuring elements