A QR code-based user-friendly visual cryptography scheme

Area of Science:

• Computer Science
• Information Security
• Cryptography

Background:

• The proliferation of the internet and smart devices enables easy image transmission, creating significant image security challenges.
• Traditional Visual Cryptography Schemes (VCS) offer keyless secret sharing but often produce noise-like shares, hindering practical application.
• The Human Visual System (HVS) is leveraged in VCS for computation-free secret image recovery through share superposition.

Purpose of the Study:

• To propose a novel QR code-based expansion-free and meaningful visual cryptography scheme (QEVCS).
• To address the limitations of traditional VCS, specifically noise-like shares and potential security risks during transmission.
• To maintain the computation-free nature of VCS while ensuring the recovered image size matches the original secret image.

Main Methods:

• Developed a QR code-based visual cryptography scheme (QEVCS).
• Generated visually appealing and meaningful QR code shares for enhanced security and discretion.
• Implemented a gray-level limitation on halftoned images to preserve image quality and size during recovery.

Main Results:

• QEVCS successfully generates meaningful QR code shares, attracting less attention from attackers on public networks.
• The scheme eliminates noise-like shares inherent in traditional VCS.
• The size of the recovered image is identical to the original secret image, and recovery is computation-free.

Conclusions:

• QEVCS provides an effective solution for enhancing image security in the digital age.
• The novel scheme improves upon traditional VCS by offering visually appealing, meaningful shares and maintaining original image dimensions.
• QEVCS demonstrates significant effectiveness in preserving image privacy during transmission over public networks.