gbanyan da455791de Paper A v13 rev8: fusion-review revision (29 items) + verified data analysis
Address all 29 items from the fused reviewer report (Gemini 3.1 Pro +
ChatGPT 5.5 + Opus 4.8): 3 fatal, 4 severe, arbitration A/B, 5 fusion-new,
15 minor. All new numbers computed from signature_analysis.db; nothing
fabricated.

Claim honesty (F1/F3/F4/F7/G3):
- Retract all "139x the floor" comparisons; ICCR -> between-accountant
  specificity proxy throughout; state within-accountant FPR is not
  estimable and ICCR is not even a bound (anti-conservative direction).
- Firm A reframed as quasi-positive known-positive benchmark (not blinded).
- byte-identity recast as prevalence signal, not a recall/sanity check.
- tunable -> single-direction conservativeness dial (no P-R frontier).

New data analysis (verified, bit-reproducible via committed scripts):
- F2/G1 (Sec V-B): 880-PDF imaging-pipeline audit (Table V) - plain scans
  82% (2013) -> 1% (2021); producer strings name scanner hardware
  (Fuji Xerox D125 etc.); substrate transforms at 2020/21 = named confound.
- F5 (Sec IV-C): four robustness checks - pool-size stratification,
  accountant-clustered bootstrap (gap 53.7pp [49.5,57.5]), firm+year FE
  logistic (B/C/D OR 0.06-0.12), leave-one-year-out (gap 53.1-54.9pp).
- byte-identity era split: 30 scan-era (18 Firm A, pipeline-robust) vs
  232 digital-era (detectability-inflated, hedged).
- G5: archive-wide 888 expected chance HC flags [677,1098].
- M4: Figure 3 replaced with real 2D density (n=150,441).

Structure/minor: abstract restructured (M1); operational definition (M2);
interview disclaimer (M3); Threats to Validity subsection (M8); review
protocol framed as design not evidence (M9); N reconciliations (M10/M11);
Table II-c 2020-23 five-way (M12); Section refs, American spelling,
notation table (M5/M13/M15); reference URLs verified (M14).

Open (author-only): placeholders (M13), II-b/IV table merge (M15).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Qn59FdF9JMyfFg3sjcUNNG
2026-06-23 14:36:51 +08:00

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

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

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.

S
Description
Automated extraction of handwritten Chinese signatures from PDF documents using hybrid VLM + Computer Vision approach. 70% recall, 100% precision.
Readme 14 MiB
Languages
Python 100%