Create thumbnail by resizing image in Python

Sometimes we need to create thumbnails of certain size from image. In this post I show you how to create thumbnail by resizing image in Python.
Here is the Python code for creating thumbnail / resizing an image:

import Image

def generate_and_save_thumbnail(imageFile, h, w, ext):
    image = Image.open(imageFile)
    image = image.resize((w, h), Image.ANTIALIAS)
    outFileLocation = "./images/"
    outFileName = "thumb"
    image.save(outFileLocation + outFileName + ext)

# set the image file name here
myImageFile = "myfile.jpg"
# set the image file extension
extension = ".jpg"
# set height
h = 200
# set width
w = 200

generate_and_save_thumbnail(myImageFile, h, w, extension)

The second argument of image.resize() is the filter. You have several options there:

• Image.ANTIALIAS
• Image.BICUBIC
• Image.BILINEAR
• Image.NEAREST

Each uses different algorithm. For downsampling (reducing the size) you can use ANTIALIAS. Other filers may increase the size.

You can also look at the following Python modules:

• imageop
• imghdr