In this article we will see how we can create a labelled image from the normal image in mahotas. For this we are going to use the fluorescent microscopy image from a nuclear segmentation benchmark. We can get the image with the help of command given below
mahotas.demos.nuclear_image()
Below is the nuclear_image
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
In order to do this we will use mahotas.label method
Syntax : mahotas.label(image)
Argument : It takes loaded image object as argument
Return : It returns the labelled image and the integer i.e number of labels
Note : The input of the label should be the filtered image object and it should have the threshold and it is preferred that image should have gaussian filter for removing sharper edges.
In order to filter the image we will take the image object which is numpy.ndarray and filter it with the help of indexing, below is the command to do this
image = image[:, :, 0]
Example 1 :
Python3
# importing required libraries import mahotas import numpy as np from pylab import imshow, show import os # loading nuclear image f = mahotas.demos.load( 'nuclear' ) # setting filter to the image f = f[:, :, 0 ] # show the image print ( "Image" ) imshow(f) show() # setting gaussian filter f = mahotas.gaussian_filter(f, 4 ) # setting threshold value f = (f> f.mean()) # creating a labelled image labelled, n_nucleus = mahotas.label(f) # showing the labelled image print ( "Labelled Image" ) imshow(labelled) show() |
Output :
Example 2 :
Python3
# importing required libraries import numpy as np import mahotas from pylab import imshow, show # loading image img = mahotas.imread( 'dog_image.png' ) # filtering the image img = img[:, :, 0 ] print ( "Image" ) # showing the image imshow(img) show() # setting gaussian filter gaussian = mahotas.gaussian_filter(img, 15 ) # setting threshold value gaussian = (gaussian > gaussian.mean()) # creating a labelled image labelled, n_nucleus = mh.label(gaussian) print ( "Labelled Image" ) # showing the gaussian filter imshow(labelled) show() |
Output :