Mahotas – Euler number of Image

In this article, we will see how we can get the euler number of the image in mahotas. The Euler number is a measure of the topology of an image. It is defined as the total number of objects in the image minus the number of holes in those objects. You can use either 4- or 8-connected neighborhoods.

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.euler method

Syntax : mahotas.euler(img)

Argument : It takes image object as argument

Return : It returns integer
 

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 

Output : 

Image threshold using Otsu Method

Euler Number of Image : 54.25

Another example 

Output : 

Image threshold using Otsu Method 

Euler Number of Image : 76.75