gbanyan
918d55154a
Six minor edits to reduce word count: - 'a YOLOv11 detector localizes signatures' -> 'YOLOv11 localizes signatures' - 'filed in Taiwan over 2013-2023' -> 'Taiwan audit reports (2013-2023)' - 'statistical analysis is scoped to the Big-4 sub-corpus (437 CPAs, 150,442 signatures)' -> 'analysis is scoped to the Big-4 sub-corpus (437 CPAs; 150,442 signatures)' - 'Wilson 95% upper bound 1.45%' -> 'Wilson upper bound 1.45%' - 'cross-scope check (n = 686) preserves the K=3 + box-rule Spearman convergence with drift 0.007' -> 'check (n = 686) preserves the K=3 + box-rule Spearman convergence (drift 0.007)' All numerical anchors preserved. Phase 4 prose v2 now within IEEE Access 250-word abstract limit. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com> EOF
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
cd /Volumes/NV2/pdf_recognize
source venv/bin/activate
python extract_pages_from_csv.py
Step 2: Extract Signatures
python extract_signatures_hybrid.py
Documentation
- PROJECT_DOCUMENTATION.md - Complete project history, all approaches tested, detailed results
- README_page_extraction.md - Page extraction documentation
- 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 for complete details.