🏗️ Algiers Building Density

Interactive building density heatmap of Algiers, Algeria — derived from Sentinel-2 satellite imagery and OpenStreetMap data. Explore urban density patterns across the capital.

---

Features

• 🗺️ Interactive heatmap of building density across Algiers
• 📊 District-level statistics and comparisons
• 🛰️ Derived from Sentinel-2 NDBI (Normalized Difference Built-up Index)
• 🏘️ OpenStreetMap building footprint overlay
• 📈 Temporal density evolution charts
• 🌐 Deployed on Streamlit Cloud

Quick Start

git clone https://github.com/OMUZ9924/algiers-building-density.git
cd algiers-building-density
pip install -r requirements.txt
streamlit run app.py

How It Works

1. Sentinel-2 NDBI — Compute built-up index from SWIR and NIR bands
2. OSM Footprints — Download building polygons via Overpass API
3. Grid Aggregation — Count buildings per 500m grid cell
4. Visualization — Folium/Plotly heatmap with district boundaries

Project Structure

algiers-building-density/
├── src/
│   ├── fetch_osm.py        # Download OSM building data
│   ├── compute_ndbi.py     # Sentinel-2 NDBI computation
│   ├── grid.py             # Spatial grid aggregation
│   └── visualize.py        # Map generation
├── app.py                  # Streamlit dashboard
├── data/                   # Cached data (gitignored)
├── requirements.txt
└── README.md

Built With

• Folium — Interactive maps
• Plotly — Charts and statistics
• GeoPandas — Spatial operations
• OSMnx — OpenStreetMap data
• Streamlit — Web dashboard

License

MIT