Mahotas - RGB to Gray Conversion

In this article we will see how we can covert rgb image to gray in mahotas. An RGB image, sometimes referred to as a truecolor image, is stored in MATLAB as an m-by-n-by-3 data array that defines red, green, and blue color components for each individual pixel.

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.colors.rgb2greymethod

Syntax : mahotas.colors.rgb2gray(img)

Argument :It takes image object as argument

Return : It returns image object

Note : It can convert image to greyscale as using rgb2grey or rgb2gray, both work). This conversion uses a visually realistic method (which weighs the green channel more heavily as human eyes are more sensitive to it)

Below is the implementation

# importing required libraries 
import mahotas 
import mahotas.demos 
from pylab import gray, imshow, show 
import numpy as np 
   
# loading iamge 
img = mahotas.demos.load('lena') 
  
   
# showing image 
print("Image") 
imshow(img) 
show() 
  
# rgb to gray 
new_img = mahotas.colors.rgb2gray(img) 
  
# showing new image 
print("New Image") 
imshow(new_img) 
show() 

Output :

Image

New Image

Another example

# importing required libraries 
import mahotas 
import numpy as np 
import matplotlib.pyplot as plt 
import os 
   
# loading iamge 
img = mahotas.imread('dog_image.png') 
        
# fltering image 
img = img[:, :, :3] 
  
# showing image 
print("Image") 
imshow(img) 
show() 
  
# rgb to gray 
new_img = mahotas.colors.rgb2gray(img) 
  
# showing new image 
print("New Image") 
imshow(new_img) 
show() 

Output :

Image

New Image

My Personal Notes

Recommended Posts:

rakshitarora

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