elias-dzobo/poseidon

Satellite flood detection for Ghana - U-Net segmentation over Sentinel-1 SAR and Sentinel-2 optical imagery, with a vision-language model turning masks into structured flood reports. # Poseidon — Satellite Flood Detection System End-to-end satellite-based flood detection for Ghana (starting with Accra). Poseidon ingests Sentinel-1 SAR + Sentinel-2 optical data, runs a U-Net segmentation model to produce pixel-level flood masks, then passes the result to a fine-tuned **LFM2.5 VL-450M** vision-language model to generate structured flood situation reports. ## Pipeline ``` Sentinel-1 + Sentinel-2 + DEM → Preprocessing → Feature Stack → U-Net (flood mask) → LFM2.5 VL (flood report) → GeoTIFF + GeoJSON + JSON/PDF report ``` ## Project structure ``` config/ — settings.yaml (AOI, thresholds), model_config.yaml data/ — raw/, processed/, features/, labels/, training_pairs/ src/ ingestion/ — Sentinel-1/2 downloaders + auxiliary data (DEM, JRC) preprocessing/ — SAR chain, optical cloud mask, feature stacking, composites models/ unet/ — architecture, dataset, train, predict vlm/ — LFM2.5 wrapper, dataset, LoRA finetune, report generation pipeline/ — end-to-end orchestrator (run_detection.py) output/ — map writer (GeoTIFF/GeoJSON), report writer (JSON/text/PDF) notebooks/ — exploration and training notebooks tests/ ``` ## Key design decisions - **U-Net first** — pixel-wise flood segmentation on 7-channel feature stacks (VV, VH, VV/VH ratio, NDWI, MNDWI, HAND, slope) - **LFM2.5 VL second** — scene-level reasoning → structured JSON flood report - **SAR false-color composite** — VV→R, VH→G, VV/VH→B, bridging SAR to the VLM vision encoder - **LoRA fine-tuning** — rank-16 LoRA on q/k/v/o projections with 4-bit QLoRA - **Ghana-specific** — Odaw River basin, Korle Lagoon, seasonal calendar (Apr–Jun / Sep–Nov) ## Quickstart ```bash pip install -r requirements.txt python -m src.pipeline.run_detection --config config/settings.yaml ``` > Raw/processed satellite data and model weights are excluded from the repo (see `.gitignore`).