[mmskelmrec] [Up] [mmhomothick] Intervals (hit-or-miss templates)

mmendpoints
Interval to detect end-points.

Synopsis

Iab = mmendpoints( OPTION = "LOOP" )

Implemented in Python.

Input

OPTION

String

'LOOP' or 'HOMOTOPIC'

Default: "LOOP"

Output

Iab

Interval

Description

mmendpoints creates an interval that is useful to detect end-points of curves (i.e., one pixel thick connected components) in binary images. It can be used to prune skeletons and to mark objects transforming them in a single pixel or closed loops if they have holes. There are two options available: LOOP, deletes all points but preserves loops if used in mmthin; HOMOTOPIC, deletes all points but preserves the last single point or loops.

Examples

Interval visualization

>>> print mmintershow(mmendpoints())

. . . 
0 1 0 
0 0 0

>>> print mmintershow(mmendpoints('HOMOTOPIC'))

. 1 . 
0 1 0 
0 0 0

Pruning

>>> f = mmreadgray('pcbholes.tif')

>>> mmshow(f)

>>> f1 = mmthin(f)

>>> mmshow(f1)

>>> f2 = mmthin(f1,mmendpoints(),20)

>>> mmshow(f2)


f	f1


f2

Homotopic marking

>>> fn = mmthin(f1,mmendpoints('HOMOTOPIC'))

>>> mmshow(mmdil(fn))


mmdil(fn)

Equation

Source Code
        def mmendpoints(OPTION="LOOP"):
    from string import upper
    Iab = None
    OPTION = upper(OPTION)
    if OPTION == 'LOOP':
        Iab = mmse2hmt(mmbinary([[0,0,0],
                                  [0,1,0],
                                  [0,0,0]]),
                        mmbinary([[0,0,0],
                                  [1,0,1],
                                  [1,1,1]]))
    elif OPTION == 'HOMOTOPIC':
        Iab = mmse2hmt(mmbinary([[0,1,0],
                                  [0,1,0],
                                  [0,0,0]]),
                        mmbinary([[0,0,0],
                                  [1,0,1],
                                  [1,1,1]]))
    return Iab
    
      

mmfreedom	Control automatic data type conversion.
mmhomothick	Interval for homotopic thickening.
mmhomothin	Interval for homotopic thinning.
mmsupcanon	Union of sup-generating or hit-miss operators.
mmsupgen	Sup-generating (hit-miss).
mmthin	Image transformation by thinning.
mmse2hmt	Create a Hit-or-Miss Template (or interval) from a pair of structuring elements.
mmintershow	Visualize an interval.

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

mmendpoints Interval to detect end-points.