PNG Image Resizer

A command-line tool written in Python to batch process and resize PNG images to a perfect square, with the option to remove extra transparent padding.

Features

• Automatic Cropping: Removes excess transparent space around the image's content before resizing.

• Square Sizing: Resizes images to a square canvas, using either a user-specified size or the largest dimension of the original image.

• Aspect Ratio Preservation: Centers the image on the new canvas, ensuring the original aspect ratio is maintained.

• Batch Processing: Processes all PNG files within a specified folder.

Prerequisites

You need Python 3 installed on your system. This script requires the Pillow library for image manipulation, which you can install and run with uv.

uv pip install Pillow

How to Use

1. Save the Script: Save the Python code as a file named main.py.

2. Run from Terminal: Open your terminal or command prompt and navigate to the directory where you saved the script.

3. Run the Script with uv: After installing the prerequisites, you can run the script using uv run. This command handles finding the correct Python interpreter and executing the script.

   Basic Usage: To process all PNGs in a folder and resize them to a square based on their largest dimension:

   uv run main.py /path/to/your/images

   This will create a resized_images subfolder within your specified directory and save the output there.

   Specify a Custom Size: To process all PNGs in a folder and resize them to a fixed 500x500 canvas:

   uv run main.py /path/to/your/images --size 500

Example

Let's say you have a folder named my_photos with these files:

my_photos/
├── logo_with_padding.png (1000x500)
├── photo_tall.png (400x800)
└── another_photo.png (600x600)

Running the script with the basic command:

uv run main.py my_photos

The script will process each file and save the output in my_photos/resized_images/:

• logo_with_padding.png will be cropped to its content (let's say 800x400) and then resized to an 800x800 square.
• photo_tall.png will be resized to an 800x800 square.
• another_photo.png will remain a 600x600 square (though its file properties will be updated).