SSIM Calculator

A command-line tool to calculate the Structural Similarity Index (SSIM) between two PNG images.

Installation

1. Create a virtual environment:

python -m venv .venv

2. Activate the virtual environment:

# On Linux/macOS
source .venv/bin/activate

# On Windows
.venv\Scripts\activate

3. Install dependencies:

pip install -r requirements.txt

Usage

Calculate SSIM between two PNG images:

python run.py image1.png image2.png

Example

python run.py photo1.png photo2.png

Output:

SSIM Index: 0.8542

Features

• Automatically trims images by removing background color (based on top-left pixel)
• Converts images to grayscale for comparison
• Resizes images to the same dimensions for accurate comparison
• Returns SSIM index value between -1 and 1 (higher values indicate greater similarity)