# Oliver: Provable Witness

> Create tamper-proof media with cryptographic hash chains and C2PA manifests. Capture, verify, and share photos and videos you can prove are authentic.

Oliver is a mobile app for iOS and Android developed by Kuip Limited. It turns your device into a cryptographic evidence tool by building SHA3-256 hash chains over every video keyframe, audio frame, and sensor reading (GPS, compass, accelerometer) captured or imported.

## Key Features

- **Real-time hash chaining**: Every video keyframe, audio sample, GPS coordinate, compass heading, and accelerometer reading is individually hashed (SHA3-256) and linked to the previous one. If a single frame is altered, the entire chain breaks.
- **C2PA Content Credentials**: Oliver embeds C2PA manifests (version 2.0) directly into media files, following the industry standard for content authentication and provenance.
- **Capture**: Record video and audio with simultaneous sensor data collection and real-time hash chain generation.
- **Import**: Generate hash chains for existing media files (MP4, MOV, JPG, PNG, AAC, MP3, WAV, and more).
- **Verify**: Re-compute hash chains to confirm nothing has been modified. Frame-level tamper detection identifies exactly where modification occurred.
- **Share**: Export verified media as .oliver packages that recipients can independently verify.
- **Geolocation proofs**: Record tamper-proof trails of GPS coordinates, compass headings, and accelerometer data to prove you walked a path or were at a specific location.
- **Document scanning (OCR)**: Capture text from documents using optical character recognition and hash the results into a verifiable claim.
- **3D depth capture**: Use LiDAR or TrueDepth sensors to capture 3D point clouds and face meshes as PLY files with cryptographic proofs.
- **Web page capture**: Save and hash HTML content from websites to prove what a page said at a specific time.
- **Works offline**: All capture, hashing, and verification happens locally on-device. No cloud required.

## Use Cases

- Journalists documenting events in the field
- Legal professionals gathering admissible evidence
- Insurance adjusters recording claims
- Human rights organizations preserving testimony
- Content creators proving originality

## Technical Details

- Hash algorithm: SHA3-256
- Hash chain structure: H_i = hash(H_{i-1} || frame_data), with genesis block of zeros
- Chains maintained for: video keyframes, audio frames, GPS readings, compass readings, accelerometer readings
- Content credentials: C2PA 2.0 manifests with self-signed certificates
- Local storage: SQLite database on device
- Media formats: MP4, MOV, JPG, PNG, AAC, MP3, WAV, OGG, FLAC, PLY (3D models)

## Links

- Website: https://oliver.provable.dev
- App Store: https://apps.apple.com/app/id6760938377
- Google Play: https://play.google.com/store/apps/details?id=dev.provable.oliver
- Privacy Policy: https://oliver.provable.dev/privacy
- Terms of Service: https://oliver.provable.dev/terms