Image Processing Toolbox | ![]() ![]() |
Syntax
Description
BW = imregionalmax(I)
finds the regional maxima of I
. imregionalmax
returns a binary image, BW
, the same size as I,
that identifies the locations of the regional maxima in I
. In BW
, pixels that are set to 1
identify regional maxima; all other pixels are set to 0.
Regional maxima are connected components of pixels with the same intensity value, t, whose external boundary pixels all have a value less than t.
By default, imregionalmax
uses 8-connected neighborhoods for 2-D images and 26-connected neighborhoods for 3-D images. For higher dimensions, imregionalmax
uses conndef(ndims(I),'maximal')
.
BW = imregionalmax(I,CONN)
computes the regional maxima of I
using the specified connectivity. CONN
may have any of the following scalar values.
Connectivity may be defined in a more general way for any dimension by using for CONN
a 3-by-3-by- ...-by-3 matrix of 0
's and 1
's. The 1
-valued elements define neighborhood locations relative to the center element of CONN
. Note that CONN
must be symmetric about its center element.
Class Support
I
can be any nonsparse, numeric class and any dimension. BW
is logical
.
Example
A = 10*ones(10,10); A(2:4,2:4) = 22; % maxima 12 higher than surround A(6:8,6:8) = 33; % maxima 23 higher than surround A(2,7) = 44; A(3,8) = 45; A(4,9) = 44; A = 10 10 10 10 10 10 10 10 10 10 10 22 22 22 10 10 44 10 10 10 10 22 22 22 10 10 10 45 10 10 10 22 22 22 10 10 10 10 44 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 33 33 33 10 10 10 10 10 10 10 33 33 33 10 10 10 10 10 10 10 33 33 33 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 regmax = imregionalmax(A) regmax = 0 0 0 0 0 0 0 0 0 0 0 1 1 1 0 0 0 0 0 0 0 1 1 1 0 0 0 1 0 0 0 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 0 0 0 0 0 0 0 1 1 1 0 0 0 0 0 0 0 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
See Also
conndef
, imreconstruct
, imregionalmin
![]() | imreconstruct | imregionalmin | ![]() |