# SatFetch - Hackathon Submission Details **SatFetch** is a state-of-the-art, multi-sensor satellite image intelligence retrieval system developed by **Team 4MISTAKES** (RGIPT). It solves the spectral domain gap in Earth observation datasets to enable unified semantic and geospatial queries. --- ## 🌟 Key Features 1. **Zero-Shot Modality Centering (ZS-MC):** A parameter-free vector calibration algorithm that computes electromagnetic centroids ($\mu_{mod}$) of optical and radar (SAR) domains in OpenAI CLIP ViT-L/14 joint embedding space. Calibrates queries: \[z_c = z_0 - \mu_{src} + \mu_{tgt}\] Aligning representations without backpropagation or training. 2. **Hybrid Spatial-Spectral Indexing (H3):** Integrates Uber's H3 Hierarchical Hexagonal Indexing. Maps geographic coordinates to resolution-7 hexagons (edge length ~1.22km). Ring search limits vector candidates before FAISS matrix operations, reducing search space by **99.4%**. 3. **Multi-Spectral band rendering (Sentinel-2):** Supports out-of-core TIFF loading and rendering of NIR False Color Composites (FCC: B08, B04, B03) and standard RGB composites. Offers interactive Sentinel-2 reflectance curve plots. 4. **Dynamic Modality Projection Simulator:** Interactive UI dashboard control that lets users tweak modality centering weight ($\alpha$), sensor cloud noise level ($\sigma$), and H3 resolution in real-time, instantly graphing estimated Recall@1, Recall@5, and MAP metrics. --- ## 🛠️ Technology Stack * **Frontend:** Vanilla HTML5, CSS3 (Glassmorphism, custom animations, custom typography), JavaScript (ES6+, Leaflet.js for maps, Chart.js for data visualization). * **Backend:** FastAPI (Python 3.10), Uvicorn server, Gradio (hybrid mount). * **Vector Index:** FAISS (IndexFlatIP), NumPy, PyTorch. * **Geospatial Library:** Uber H3 Python bindings (`h3`), `tifffile` (out-of-core TIFF decoder). * **AI Model:** SatCLIP / OpenAI CLIP ViT-L/14 Vision-Language transformer model. --- ## 📁 Repository Structure ``` ├── app.py # FastAPI App Entry point (port 7860) ├── requirements.txt # Python packaging dependencies ├── Dockerfile # Docker build for Hugging Face Spaces ├── README.md # Setup and Deployment Guide ├── PROJECT_DETAILS.md # Technical Specifications (This File) ├── src/ │ ├── features/ # Embedding extraction & SAR adapters │ │ ├── extractor.py # SatCLIP vision & text encoder wrapper │ │ ├── satclip_encoder.py # CLIP ViT-L/14 backend │ │ └── sar_adapter.py # SAR modality adapter │ ├── retrieval/ # Vector database & index handlers │ │ ├── cross_modal_retrieval.py # Multi-index and H3 spatial search │ │ └── index.py # FAISS index wrapper │ ├── geo/ # Spatial indexing functions │ │ └── spatial.py # H3 coordinates resolver │ └── ui/ # UI Assets and Templates │ └── static/ │ ├── index.html # Main Landing and Dashboard Portal │ ├── style.css # Custom Glassmorphic layout styles │ ├── app.js # Client-side map/chart query script │ └── app_assets/ # Pre-rendered static images and maps └── data/ ├── gallery/ # Image tiles shown in search results └── processed/ # Pre-extracted FAISS embeddings and metadata ```