Python Pillow - Merging Images

Pillow (PIL) library is used for merging or combining individual bands of an image to create a new multiband image. It's particularly useful when working with multispectral or multichannel images such as RGB or CMYK images and we want to create a new image by merging specific bands.

In pillow we have the merge() method which belongs to the Image module which is used to merge the given input images.

This method is useful for tasks like combining multiple channels of satellite or medical images, creating custom color images or working with images that have separate channels that need to be combined into a single image.

Syntax

Here's the syntax and usage of the Image.merge() method −

Image.merge(mode, bands)

Where,

• mode − This parameter specifies the mode of the new multiband image. It should match the mode of the individual bands we want to merge. Common modes include "RGB" for color images, "RGBA" for images with an alpha channel, and "CMYK" for cyan, magenta, yellow and black color spaces.

• bands − This parameter is a tuple of individual image bands that we want to merge. Each band should be a single-channel image or a grayscale image.

Example - Merging Image with RGB Bands

Here is an example of how to use the Image.merge() method to merge the red, green and blue bands of an image to create a new RGB image.

main.py

from PIL import Image

image = Image.open("Images/butterfly.jpg")
r, g, b = image.split()
image = Image.merge("RGB", (b, g, r))
image.show()

Image to be used

Output

Example - Merging Images

Here, in this example we are merging two input images by using the merge() method of the Image module of pillow library.

from PIL import Image
image1 = Image.open("Images/butterfly.jpg")
image2 = Image.open("Images/handwriting.jpg")

#resize, first image
image1 = image1.resize((426, 240))
image1_size = image1.size
image2_size = image2.size
new_image = Image.new("RGB",(2*image1_size[0], image1_size[1]), (250,250,250))
new_image.paste(image1,(0,0))
new_image.paste(image2,(image1_size[0],1))
new_image.save("Output_Images/merged.jpg")
new_image.show()

The two images to be merged

Output