Capture Provenance Profile (CPP)

Open specification for cryptographically verifiable media capture provenance.

CPP proves "this media was actually captured at this moment" with deletion detection, external timestamping, and privacy-by-design. Part of the VAP (Verifiable AI Provenance) Framework.

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🎯 Why CPP?

Existing content provenance solutions face critical challenges:

Problem	CPP Solution
Self-attestation abuse	RFC 3161 TSA mandatory (independent third-party)
Metadata stripped by platforms	Verification URL + PHASH recovery
No deletion detection	Completeness Invariant (XOR hash sum)
"Verified" misleads users	"Provenance Available" terminology
Trust list gatekeeping	Open TSA ecosystem (free options)
Exclusion list vulnerabilities	NO exclusion lists

🔑 Key Features

1. Completeness Invariant

Mathematically detect ANY missing events in the capture chain:

hash_sum = H(E₁) ⊕ H(E₂) ⊕ ... ⊕ H(Eₙ)
Delete any event → hash_sum mismatch → VIOLATION DETECTED

2. External Third-Party Verification

RFC 3161 TSA timestamps eliminate self-attestation:

Creator signs → TSA countersigns → INDEPENDENT VERIFICATION

3. Privacy by Design

• Location: OFF by default
• Zero-knowledge biometric attestation (ACE)
• GDPR-compliant crypto-shredding

4. C2PA Interoperability

Complement, not compete:

• C2PA: "How was this edited?"
• CPP: "Was this actually captured?"

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📁 Repository Structure

cpp-spec/
├── docs/
│   └── CPP-Specification-v1.0.md    # Main specification
├── schemas/
│   ├── cpp/                          # Core JSON schemas
│   └── ace/                          # ACE extension schemas
├── examples/
│   ├── cpp-core/                     # Core examples
│   └── cpp-ace/                      # ACE examples
├── test-vectors/                     # Conformance test data
├── regulatory-mapping/               # EU AI Act, GDPR mapping
└── tools/                            # Reference utilities

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🚀 Quick Start

Verification URL

Every CPP-protected capture has a permanent URL:

https://verify.veritaschain.org/cpp/{verification_code}

Basic Event Structure

{
  "cpp_version": "1.0",
  "event_type": "CPP_CAPTURE",
  "timestamp": "2026-01-18T10:30:00.000Z",
  "payload": {
    "media_hash": "sha256:...",
    "media_type": "image/heic",
    "collection_id": "album:vacation-2026"
  },
  "signature": {
    "algorithm": "Ed25519",
    "value": "base64:..."
  }
}

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📊 Conformance Levels

Level	Target	TSA Anchor	ACE	Use Case
Bronze	Hobbyists	Optional	Optional	Personal photos
Silver	Families	Daily	Optional	Family memories
Gold	Legal/Journalism	Per-capture	Required	Court evidence

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🔗 Related Projects

• VCP (VeritasChain Protocol) - Algorithmic trading
• CAP (Creative AI Profile) - AI content generation
• VAP Framework - Parent framework

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📜 UI Guidelines

CPP explicitly avoids "Verified" terminology:

✅ Use	❌ Avoid
"Provenance Available"	"Verified"
"Capture Recorded"	"Authenticated"
ℹ️ Information icon	✓ Checkmark

Required disclosure: "This shows capture data. It does NOT verify content truthfulness or source trustworthiness."

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🤝 Contributing

We welcome contributions! See CONTRIBUTING.md.

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📄 License

• Specification: CC BY 4.0
• Code examples: Apache 2.0

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📞 Contact

• Standards: standards@veritaschain.org
• Technical: technical@veritaschain.org
• Website: https://veritaschain.org

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Copyright © 2026 VeritasChain Standards Organization