# PDF Signature Extraction System

Automated extraction of handwritten Chinese signatures from PDF documents using hybrid VLM + Computer Vision approach.

## Quick Start

### Step 1: Extract Pages from CSV
```bash
cd /Volumes/NV2/pdf_recognize
source venv/bin/activate
python extract_pages_from_csv.py
```

### Step 2: Extract Signatures
```bash
python extract_signatures_hybrid.py
```

## Documentation

- **[PROJECT_DOCUMENTATION.md](PROJECT_DOCUMENTATION.md)** - Complete project history, all approaches tested, detailed results
- **[README_page_extraction.md](README_page_extraction.md)** - Page extraction documentation
- **[README_hybrid_extraction.md](README_hybrid_extraction.md)** - Hybrid signature extraction documentation

## Current Performance

**Test Dataset:** 5 PDF pages
- **Signatures expected:** 10
- **Signatures found:** 7
- **Precision:** 100% (no false positives)
- **Recall:** 70%

## Key Features

✅ **Hybrid Approach:** VLM name extraction + CV detection + VLM verification
✅ **Name-Based:** Signatures saved as `signature_周寶蓮.png`
✅ **No False Positives:** Name-specific verification filters out dates, text, stamps
✅ **Duplicate Prevention:** Only one signature per person
✅ **Handles Both:** PDFs with/without text layer

## File Structure

```
extract_pages_from_csv.py          # Step 1: Extract pages
extract_signatures_hybrid.py       # Step 2: Extract signatures (CURRENT)
README.md                          # This file
PROJECT_DOCUMENTATION.md           # Complete documentation
README_page_extraction.md          # Page extraction guide
README_hybrid_extraction.md        # Signature extraction guide
```

## Requirements

- Python 3.9+
- PyMuPDF, OpenCV, NumPy, Requests
- Ollama with qwen2.5vl:32b model
- Ollama instance: http://192.168.30.36:11434

## Data

- **Input:** `/Volumes/NV2/PDF-Processing/master_signatures.csv` (86,073 rows)
- **PDFs:** `/Volumes/NV2/PDF-Processing/total-pdf/batch_*/`
- **Output:** `/Volumes/NV2/PDF-Processing/signature-image-output/`

## Status

✅ Page extraction: Tested with 100 files, working
✅ Signature extraction: Tested with 5 files, 70% recall, 100% precision
⏳ Large-scale testing: Pending
⏳ Full dataset (86K files): Pending

See [PROJECT_DOCUMENTATION.md](PROJECT_DOCUMENTATION.md) for complete details.