gbanyan
3c7fcc010f
- Re-anchor inter-CPA coincidence-rate (ICCR) calibration on a normative non-Firm-A baseline (Firms B/C/D); Firm A held out as an out-of-sample target. Locked canonical numbers (codex-audited; Scripts 46/52/53): per-comparison HC 0.00014->0.000018, per-signature HC 0.0116, per-document HC+MC 0.34->0.1905; KDE crossover 0.837 retained corpus-wide. - Reposition as an operator-tunable, semi-automated screening/triage framework (title -> "Automated Screening..."): HC = high-specificity operating point; MC band demoted to low-specificity advisory; Firm A = demonstration that the screening surfaces a templated end, audit-quality implications deferred. - Apply codex prose-review fixes: triage-neutral five-way labels, soften mechanism/specificity wording, supersede MC claim-strength, update stale Appendix script references (40b/43/45 -> 46/52/53). - Trim pass: compress Sec. V discussion + Sec. III echoes (27.7k -> 26.8k words); no substantive content removed. - Add analysis scripts 45-53 (firm-year trends; BCD-only ICCR recompute; canonical-sampler locked numbers; Firm-A out-of-sample; BCD regression + cross-firm hit matrix). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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.