How to posterize an image by reducing colors in Python

Proper use of posterization can really make an image pop, adding a pleasing sense of style with very little effort. It is a perfect fit for any photo editing app, especially when it can be adjusted on the user’s end. So how will we be able to add this type of functionality without spending hour after hour of testing and debugging? Simple, there’s an API out there that will do it for us, we just need to set it up and call it.

Our setup involves pip install, as you see here:

pip install cloudmersive-image-api-client

And now we can create our API instance with a trial key and then call filter_posterize with our color levels and image file path as arguments:

from __future__ import print_function
import time
import cloudmersive_image_api_client
from cloudmersive_image_api_client.rest import ApiException
from pprint import pprint
# Configure API key authorization: Apikey
configuration = cloudmersive_image_api_client.Configuration()
configuration.api_key['Apikey'] = 'YOUR_API_KEY'
# Uncomment below to setup prefix (e.g. Bearer) for API key, if needed
# configuration.api_key_prefix['Apikey'] = 'Bearer'
# create an instance of the API class
api_instance = cloudmersive_image_api_client.FilterApi(cloudmersive_image_api_client.ApiClient(configuration))
levels = 56 # int | Number of unique colors to retain in the output image
image_file = '/path/to/file' # file | Image file to perform the operation on.  Common file formats such as PNG, JPEG are supported.
try:
# Posterize the image by reducing distinct colors
api_response = api_instance.filter_posterize(levels, image_file)
pprint(api_response)
except ApiException as e:
print("Exception when calling FilterApi->filter_posterize: %s\n" % e)

And there it is, in all its simple glory. Let’s look at the resulting effect:

Vs the original:

What a difference!