Mahotas – Removing border effect from Wavelet Center Image

In this article we will see how we can remove the border effect from wavelet center in mahotas. Wavelets represent the scale of features in an image, as well as their position. Wavelet center will make the image small and place it in the center unlike daubechies wavelet. We use wavelet_center method to wavelet center the image.
In this tutorial we will use “luispedro” image, below is the command to load it. 

mahotas.demos.load('luispedro')

Below is the luispedro image 

In order to do this we will use wavelet_decenter method 

Syntax : mahotas.wavelet_decenter(centered_image, original_img_shape)
Argument : It takes image object and original image shape 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]

Example 1:

Python3

# importing various libraries
import numpy as np
import mahotas
import mahotas.demos
from mahotas.thresholding import soft_threshold
from pylab import imshow, show
from os import path

# loading image
f = mahotas.demos.load('luispedro', as_grey = True)


# making image wavelet center
fc = mahotas.wavelet_center(f)

# showing image
print("Image with wavelet center")
imshow(fc)
show()

# restoring image
rd = mahotas.wavelet_decenter(fc, f.shape)


# showing image
print("Restored Image")
imshow(rd)
show()

Output :

Example 2:

Python3

# importing required libraries
import mahotas
import numpy as np
from pylab import imshow, show
import os


# loading image
img = mahotas.imread('dog_image.png')

# filtering image
img = img[:, :, 0]


# making image wavelet center
fc = mahotas.wavelet_center(img)

# showing image
print("Image with wavelet center")
imshow(fc)
show()

# restoring image
rd = mahotas.wavelet_decenter(fc, img.shape)


# showing image
print("Restored Image")
imshow(rd)
show()

Output :