Mahotas – Sizes of Labelled Region
In this article we will see how we can obtain sizes of labelled region in mahotas. Labelled images are integer images where the values correspond to different regions. I.e., region 1 is all of the pixels which have value 1, region two is the pixels with value 2, and so on. By convention, region 0 is the background and often handled differently. We can create a labelled region with the help of mahotas.label method.
In order to do this we will use mahotas.label_size method
Syntax : mahotas.labelled_size(labelled_region)
Argument : It takes numpy.ndarray object as argument i.e labelled region
Return : It returns list of integer
Example 1:
Python3
# importing required libraries import mahotas as mh import numpy as np from pylab import imshow, show # creating region # numpy.ndarray regions = np.zeros(( 10 , 10 ), bool ) # setting 1 value in the region regions[ 1 , 1 ] = 1 regions[ 6 , 6 ] = 1 regions[ 4 , 4 ] = 1 regions[ 9 , 9 ] = 1 # getting labelled function labelled, nr_objects = mh.label(regions) # showing the image with interpolation = 'nearest' imshow(labelled, interpolation = 'nearest' ) show() # getting sizes of labelled region sizes = mh.labelled.labelled_size(labelled) # printing sizes for i in range ( len (sizes)): print ( "Size of region " + str (i) + " : " + str (sizes[i])) |
Output :
Size of region 0 : 96 Size of region 1 : 1 Size of region 2 : 1 Size of region 3 : 1 Size of region 4 : 1
Example 2:
Python3
# importing required libraries import mahotas as mh import numpy as np from pylab import imshow, show # creating region # numpy.ndarray regions = np.zeros(( 10 , 10 ), bool ) # setting 1 value to the region regions[: 3 , : 3 ] = 1 regions[ 6 :, 6 :] = 1 # getting labelled function labelled, nr_objects = mh.label(regions) # showing the image with interpolation = 'nearest' imshow(labelled, interpolation = 'nearest' ) show() # getting sizes of labelled region sizes = mh.labelled.labelled_size(labelled) # printing sizes for i in range ( len (sizes)): print ( "Size of region " + str (i) + " : " + str (sizes[i])) |
Output :
Size of region 0 : 75 Size of region 1 : 9 Size of region 2 : 16