C2PA Browser Verification

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C2PA Browser Verification

Youseddit extends C2PA content authentication standards to text quotes by providing a Chrome browser extension that verifies both C2PA metadata and blockchain-backed smart contract authorization.

C2PA and Blockchain Integration

The Content Authenticity Initiative (CAI) and the Coalition for Content Provenance and Authenticity (C2PA) have established standards for tracking the origin and edit history of digital content. YouSeddit extends these standards to text quotes from interviews and other sources.

C2PA Extension Architecture

Key Verification Components

  1. Standard C2PA Verification

    • Detects C2PA manifests in images and videos
    • Validates digital signatures and content integrity
    • Shows standard C2PA provenance information

  2. Text Quote C2PA Extension

    • Identifies text with C2PA metadata references
    • Extracts YouSeddit blockchain identifiers
    • Validates text matches against authenticated blockchain records

  3. Smart Contract Validation

    • Verifies the domain has a valid license to use the content
    • Validates payment status and license terms
    • Ensures proper attribution requirements are met

Verification Workflow

The C2PA verification process integrates with Youseddit’s blockchain in the following way:

  1. Content Creation

    • Source provides interview or statement
    • Content is authenticated through PGP/GPG
    • C2PA manifest is generated with YouSeddit blockchain references
    • Content is stored securely on the blockchain

  2. Content Publication

    • Publisher acquires rights through smart contracts
    • Content is published with embedded C2PA metadata
    • C2PA manifest includes blockchain references

  3. User Verification

    • Browser extension detects C2PA-enabled content
    • Extension validates C2PA manifests
    • For text quotes, extension:
      • Verifies text against blockchain records
      • Validates domain’s smart contract authorization
      • Displays verification status to the user

Technical Implementation

The verification system uses several innovative approaches:

C2PA Manifest Extensions

Youseddit extends standard C2PA manifests with blockchain-specific assertions:

{
  "assertions": [
    {
      "label": "youseddit.blockchain",
      "data": {
        "blockchainId": "0x7d931ff3a802d6c5...",
        "ledgerType": "ethereum",
        "contentType": "quote",
        "timestampVerified": "2025-03-15T14:22:31Z"
      }
    }
  ]
}

Text Quote Validation

For text quotes, the system:

  1. Extracts the exact text content
  2. Compares it against the blockchain-stored authentic version
  3. Applies fuzzy matching to account for minor formatting differences
  4. Verifies that the quote maintains the original meaning and context

Smart Contract Integration

The verification system checks:

  1. If the domain has purchased rights to use the quote
  2. If the contract is current and not expired
  3. Whether usage complies with license terms (exclusive/non-exclusive)
  4. If required attribution is properly included

Benefits of C2PA-Based Verification

This approach offers several advantages:

  • Built on Open Standards: Leverages established C2PA standards and tooling
  • Media Continuity: Applies consistent verification across text, images, and videos
  • Decentralized Trust: Combines cryptographic verification with blockchain immutability
  • Cross-Platform Compatibility: Works with all major C2PA implementations
  • Future-Proof Design: Extensible to new content types and verification methods
Last modified July 6, 2025: Update deploy.yml (d65b9c1)