README.md

---
title: Image File Compare
emoji: 🔍
colorFrom: blue
colorTo: purple
sdk: streamlit
sdk_version: 1.36.0
app_file: app.py
pinned: false
license: mit
---

# 🔍 Image File Compare

A web-based tool for comparing two images with threshold-based difference detection.

## Features

- **Multi-format support** — TIFF, FITS, PNG, JPG, BMP
- **Threshold control** — Adjustable slider to filter noise and focus on meaningful differences
- **Auto-scaling** — When image sizes differ, automatically scales one to match (configurable method)
- **Multiple scaling algorithms** — Nearest, Bilinear, Bicubic, Lanczos, Area
- **Difference visualization:**
  - Actual difference image (with optional amplification)
  - Binary mask (white = pixels exceeding threshold)
  - Colored overlay (red = differences)
  - Overlay blended on original image
- **Download outputs** — All result images downloadable as PNG or TIFF
- **Statistics** — Pixel count, percentage, max/mean difference values

## Usage

1. Upload two images (supports TIF, FITS, PNG, JPG, BMP)
2. Adjust the difference threshold in the sidebar
3. If sizes differ, choose a scaling method and which image to resize
4. View results: difference image, binary mask, colored overlay
5. Download any output using the download buttons at the bottom

## Running Locally

```bash
pip install -r requirements.txt
streamlit run app.py
```