[mmopenrec] [Up] [mmregmin] Connected Operators

mmregmax
Regional Maximum.

Synopsis

function y = mmregmax ( f , Bc )

Input

f Image Gray-scale (uint8 or uint16) image
Bc Structuring Element

Default: 3x3 elementary cross

(connectivity).

Output

y Image Binary image

Description

mmregmax creates a binary image y by computing the regional maxima of f, according to the connectivity defined by the structuring element Bc. A regional maximum is a flat zone not surrounded by flat zones of higher gray values.

Examples

Numerical example:
a = uint8([...

    5   10   10   10   10   10   10;...

    5    9    6   18    6    5   10;...

    5    9    6   18    6    8    7;...

    5    9    9   15    9    7   10;...

    5    9    9   15   12   10   10;...

    5    5    5    5   10   10   10]);

b = mmregmax(a)

b =
     0     0     0     0     0     0     0
     0     0     0     1     0     0     0
     0     0     0     1     0     1     0
     0     0     0     0     0     0     0
     0     0     0     0     0     0     0
     0     0     0     0     0     0     0

c = mmregmax(a,mmsebox)

c =
     0     0     0     0     0     0     0
     0     0     0     1     0     0     0
     0     0     0     1     0     0     0
     0     0     0     0     0     0     0
     0     0     0     0     0     0     0
     0     0     0     0     0     0     0
Gray-scale image:
f=mmreadgray('astablet.tif');

y1=mmregmax(f);

f2=mmopen(f,mmsedisk(20));

y2=mmregmax(f2);

mmshow(f);

mmshow(y1);

mmshow(f2);

mmshow(y2);
f y1
f2 y2

Equation

Algorithm

function y=mmregmax_equ( f, bc)
 if (isa(f,'uint8'))
   k = 255;
 else
   k = 65535;
 fminus = mmsubm(f,1);
 g = mmsubm(fplus,mminfrec(fminus,f,bc));
 y = mmunion(mmthreshad(g,1),mmthreshad(f,k));

See also

mmfreedom Control automatic data type conversion.
mmregmin Regional Minimum (with generalized dynamics).
mmsebox Create a box structuring element.
mmsecross Diamond structuring element and elementary 3x3 cross.
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