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Visual Cryptography Authentication (VCA)

Understanding VCA for everyone

Think of it like a special movie that only human eyes can properly see, but with some unique security features.

Frame Generation

Each "frame" of the movie is created by a one-time garbled circuit generated on the blockchain.

Garbled circuits work like secure black boxes:

  • They receive encrypted random inputs
  • Process them without revealing internal logic
  • Output only the specific frames they’re designed to create

Every frame is cryptographically unique and cannot be reused.

The Human Vision Advantage

The system uses a brain feature called persistence of vision:

  • Your eyes retain an image for ~1/30th of a second
  • When frames change rapidly (60–120 fps):
    • Your brain merges the sequence into one coherent image
    • Machines only see meaningless static

This creates a channel that only humans can perceive and decode.

Why It’s Secure

All transaction data is embedded directly into the garbled circuit, never appearing in memory.

To compromise it, an attacker would have to:

  • Capture every individual frame perfectly
  • Know how to reassemble them
  • Mimic the display timing at 60–120 fps
  • Align every pixel position precisely

Infeasible. Expensive. Ineffective.

Analogy: The Flipbook

Imagine a fast flipbook where:

  • Each page is generated by a secure black box
  • Each page looks like random noise
  • Only the human eye sees the real image when flipping quickly
  • Each book is one-time use and randomized

Visual Cryptography Simulation Example

Below is a basic demonstration of visual cryptography.

When two same-sized images of apparently random black-and-white pixels are superimposed, the Wikipedia logo appears.

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Intestellar Case

Dynamic Visual Cryptography

This is the way we leverage human perssistence of vision with a basic visual cryptography scheme.

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The garbled circuit manages the display of consecutive random frames. This ensures that the execution of the circuit does not leak any secret information, such as the one-time code or random keyboard topology associated with the transaction. The transaction message (amount, address) is also embedded into the circuit and remains inaccessible to the attacker, preventing any modifications. This creates a secure visual channel between the blockchain and the user

Garbled Circuits + Human Biology = Secure UI

This secure display channel:

  • Prevents overlay attacks and clipper malware
  • Makes tampering visible
  • Works even on infected devices
  • Makes transaction spoofing ineffective

Instead of detecting malware, it creates an environment where spoofing is useless.

Deep Tech Advantage

No need for kernel access or malware detection
Secure even on compromised devices
Simpler and clearer than traditional mobile EDR solutions

This enables hardware-wallet level security with nothing more than your smartphone.

Visual Simulation

Intesrstellar Transaction Validation Example

"A wallet's security is only as strong as its authentication system."

👇 Try it yourself:

  1. Choose your device:
    Desktop | Mobile
  2. Leave all fields empty and press “Ok”
  3. Take a screenshot.

→ Thanks to the human persistence of vision, your eyes and brain retain a visual impression for about 1/30 of a second (the exact time depends on the brightness of the image). So called “visual cryptographic shares” are generated by the Interstellar Blockchain and displayed at 60–120 frames per second on your device. This drastically disincentivizes potential attackers from building and executing fake user interfaces (so called overlay attacks) during the display session - deeming them ineffective.

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