Batch Image Compression with Python: A 20‑Line Script Tutorial

Many designers, photographers, and anyone handling high‑resolution images face the problem of large file sizes slowing down website loading or violating size limits, requiring manual compression before upload.

When dealing with dozens, hundreds, or thousands of images, manual processing becomes inefficient, so the article proposes using Python to automate lossless batch compression with only about 20 lines of code.

Project Idea : Install an existing Python image‑processing library, import the target folder, and loop through the images to compress them automatically.

Environment :

Operating System: macOS / Windows

Editor: VS Code

Python version: 3.7.4

Required modules:

import rawpy

import imageio

import os

Implementation Steps :

Install the necessary Python image‑processing modules.

Import the image folder and use a loop to process each file automatically.

Add a conditional statement to skip non‑image files.

Print the compression progress and save the compressed images to a new folder.

The article includes screenshots illustrating each step, such as installing modules, writing the loop, adding the file‑type check, and the final print statement.

Result : Running the script quickly compresses multiple photos, reducing a 20 MB image to about 2 MB—a compression ratio of roughly 90%.

Conclusion : With just 20 lines of Python code, users can efficiently batch‑compress images, dramatically improving workflow speed and saving storage space.