Mahotas – Match template to image exactly
In this article we will see how we can match a template with the image in mahotas. By matching templates we can find the specific location or things in a image with the help of structure we want to find.
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.find method
Syntax : mahotas.find(img, template)
Argument : It takes image object and template as argument
Return : It returns boolean ndarray
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()# templatetemplate = np.array([ [0, 1, 1], [0, 1, 1], [0, 1, 1]], bool)# finding template in the imagenew_img = mahotas.find(img, template)print("Image with only templates")# showing new imageimshow(new_img)show() |
Output :
Image threshold using Otsu Method
Image with only templates
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()# templatetemplate = np.array([ [0, 1, 1], [0, 1, 1], [0, 1, 1]], bool)# finding template in the imagenew_img = mahotas.find(img, template)print("Image with only templates")# showing new imageimshow(new_img)show() |
Output :
Image threshold using Otsu Method
Image with only templates
