AMBTC-based visual secret sharing with different meaningful shadows.

Area of Science:

• Cryptography
• Image Processing
• Information Security

Background:

• Traditional secret sharing using Absolute Moment Block Truncation Coding (AMBTC) suffers from inconvenient stego image management due to indistinguishable images.
• Pixel expansion in existing schemes leads to increased storage and bandwidth requirements.

Purpose of the Study:

• To develop a secret sharing scheme that addresses the management and pixel expansion issues of AMBTC-based methods.
• To enhance the security and practicality of visual secret sharing by creating visually distinct stego images.

Main Methods:

• The proposed scheme employs multiple cover images to ensure visual differentiation of stego images.
• It integrates traditional Visual Secret Sharing (VSS) to eliminate pixel expansion.
• Images are compressed using the AMBTC algorithm, obtaining quantization levels and bitmaps.

Main Results:

• Stego images are made visually distinct, reducing suspicion and increasing security.
• Pixel expansion is eliminated by fusing VSS, optimizing storage and bandwidth.
• Lossless bitmap recovery is achieved at a (k,k) threshold, with slight quality degradation solely from compression.

Conclusions:

• The developed scheme effectively manages stego images and overcomes pixel expansion.
• It offers improved security and efficiency compared to traditional AMBTC-based secret sharing methods.
• Experimental results validate the scheme's effectiveness and advantages.