How To Remove Image Background Using Python: Step-by-Step Guide with Flask API

In a world driven by visuals, high-quality images are essential for everything from e-commerce to content marketing. But often, removing the background from an image is necessary to give products, people, or objects a clean, professional look.

This tutorial will walk you through using Python to remove image backgrounds effectively, then show you how to create a Flask API so you can automate the process for bulk use or integrate it into applications.

Setting Up Your Environment

First, make sure you have Python installed. Then, we’ll install rembg, a powerful library for background removal that leverages deep learning models. We’ll also use Flask to build a simple API.

pip install rembg Flask

Step 1: Write the Python Code for Background Removal

Here’s a script that will remove the background from any image:

from rembg import remove
from PIL import Image
import io
def remove_background(input_path, output_path):
    with open(input_path, "rb") as input_file:
        input_data = input_file.read()
        output_data = remove(input_data)
        
        # Save the output as a new image file
        with open(output_path, "wb") as output_file:
            output_file.write(output_data)
# Usage example
remove_background("input_image.jpg", "output_image.png")

This script:

1. Loads the input image.
2. Processes it with the remove function from rembg to extract the main object.
3. Saves the result as a PNG file (with transparent background) for easy editing.

Step 2: Testing the Script

Run this code with your own image to check how well it removes the background. The output image will have a transparent background where you can layer it over different designs or colors.

Step 3: BONUS – Build a Background Removal Flask API

Let’s take it a step further and build a Flask API so you (or other users) can upload images and get background-removed versions in return.

API Code

from flask import Flask, request, send_file
from rembg import remove
from PIL import Image
import io
app = Flask(__name__)
@app.route("/remove-bg", methods=["POST"])
def remove_bg():
    if "file" not in request.files:
        return {"error": "No file uploaded"}, 400
    file = request.files["file"]
    # Read image data and remove background
    input_data = file.read()
    output_data = remove(input_data)
    # Send the modified image as a response
    return send_file(
        io.BytesIO(output_data),
        mimetype="image/png",
        as_attachment=True,
        attachment_filename="output_image.png"
    )
if __name__ == "__main__":
    app.run(debug=True)

API Explanation

Response: The modified image is sent back as a PNG, suitable for immediate use.

Endpoint: /remove-bg is designed to accept POST requests.

File Upload: The API expects an image file uploaded with the key file.

Background Removal: It uses remove to process the uploaded image and output a transparent background.

Response: The modified image is sent back as a PNG, suitable for immediate use.

Step 4: Running the Flask API

Run the following command to start the server:

python app.py

Your API is now live at http://127.0.0.1:5000/remove-bg. To test it, you can use tools like Postman or cURL to send a POST request with an image file.

curl -X POST -F "file=@input_image.jpg" http://127.0.0.1:5000/remove-bg --output output_image.png

This command will upload input_image.jpg and download the background-removed version as output_image.png.

Benefits of Automated Background Removal

1. Time Efficiency: Background removal through code is faster than manual editing, especially for bulk processing.
2. Consistent Results: Python-based background removal offers more consistency, ensuring clean, high-quality outputs.
3. Versatile Applications: From e-commerce and design to personal projects, background removal tools have endless uses.

Use Cases for Background Removal

Graphic Design: Prepare assets for design work quickly and effectively.

E-commerce: Showcase products on a white or custom background for a professional look.

Social Media: Add custom backgrounds or effects to make visuals stand out.

Marketing: Enhance content by layering objects or people over other images without a distracting background.

Conclusion

In just a few steps, we’ve created a powerful Python script and an accessible Flask API for removing image backgrounds. This API can be integrated into web applications, used as part of an automated image editing workflow, or offered as a service for others to use.

Now you have the power to take visual content to a new level of quality—without spending hours in photo-editing software.