In this article, we will see how we can set the element structure for erode of the image in mahotas. Erosion (usually represented by ?) is one of two fundamental operations (the other being dilation) in morphological image processing from which all other morphological operations are based. It was originally defined for binary images, later being extended to grayscale images, and subsequently to complete lattices. In order to erode the image we use mahotas.morph.erode method.
In this tutorial, we will use “luispedro” image, below is the command to load it.
mahotas.demos.load('luispedro')
Below is the luispedro image
Below is the default structure of the element for erosion, which a 1 cross
np.array([ [0, 1, 0], [1, 1, 1], [0, 1, 0]], bool)
Below is the implementation
Python3
# importing required libraries import mahotas import mahotas.demos from pylab import gray, imshow, show import numpy as np # loading image luispedro = mahotas.demos.load( 'luispedro' ) # filtering image luispedro = luispedro. max ( 2 ) # otsu method T_otsu = mahotas.otsu(luispedro) # image values should be greater than otsu value img = luispedro > T_otsu print ( "Image threshold using Otsu Method" ) # showing image imshow(img) show() # erode structure es = np.array([ [ 1 , 1 , 1 ], [ 1 , 1 , 1 ], [ 1 , 1 , 1 ]], bool ) # eroding image using element structure new_img = mahotas.morph.erode(img, es) # showing dilated image print ( "Eroded Image" ) imshow(new_img) show() |
Output :
Image threshold using Otsu Method
Eroded Image
Another example
Python3
# importing required libraries import mahotas import numpy as np import matplotlib.pyplot as plt import os # loading image img = mahotas.imread( 'dog_image.png' ) # setting filter to the image img = img[:, :, 0 ] # otsu method T_otsu = mahotas.otsu(img) # image values should be greater than otsu value img = img > T_otsu print ( "Image threshold using Otsu Method" ) # showing image imshow(img) show() # erode structure es = np.array([ [ 0 , 0 , 0 ], [ 0 , 1 , 0 ], [ 0 , 0 , 0 ]], bool ) # eroding image using element structure new_img = mahotas.morph.erode(img, es) # showing dilated image print ( "Eroded Image" ) imshow(new_img) show() |
Output :
Image threshold using Otsu Method
Eroded Image