In this article we will see how we can close holes of the image in mahotas. Closing holes means to remove the holes present in the image, closing is a process in which first dilation operation is performed and then erosion operation is performed. It eliminates the small holes from the obtained image, it is used for smoothening of contour and fusing of narrow breaks.
In this tutorial we will use “lena” image, below is the command to load it.
mahotas.demos.load('lena')
Below is the lena image
In order to do this we will use mahotas.close_holes method
Syntax : mahotas.close_holes(img)
Argument : It takes image object as argument
Return : It returns image object
Note: Input image should be filtered or should be loaded as grey
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]
Below is the implementation
Python3
# importing required librariesimport mahotasimport mahotas.demosfrom pylab import gray, imshow, showimport numpy as np # loading imageimg = mahotas.demos.load('lena') # filtering imageimg = img.max(2) # otsu methodT_otsu = mahotas.otsu(img) # image values should be greater than otsu valueimg = img > T_otsu print("Image threshold using Otsu Method") # showing imageimshow(img)show() # closing holesnew_img = mahotas.close_holes(img)print("Closed Hole Image")# showing imageimshow(new_img)show() |
Output :
Image threshold using Otsu Method
Lena Otsu
Closed Hole Image
Close Holes
Another example
Python3
# importing required librariesimport mahotasimport numpy as npfrom pylab import gray, imshow, showimport os # loading imageimg = mahotas.imread('dog_image.png')# filtering imageimg = img[:, :, 0] # otsu methodT_otsu = mahotas.otsu(img) # image values should be greater than otsu valueimg = img > T_otsu print("Image threshold using Otsu Method") # showing imageimshow(img)show() # closing holesnew_img = mahotas.close_holes(img)print("Closed Hole Image")# showing imageimshow(new_img)show() |
Output :
Image threshold using Otsu Method
Closed Hole Image
