A high-capacity coverless image steganography method based on double-level index and block matching.

Area of Science:

• Computer Science
• Information Security
• Digital Image Processing

Background:

• Coverless information steganography (CIS) uses original images for secret data transmission, resisting steganalysis.
• Existing CIS methods suffer from low embedding capacity, limiting their practical application.

Purpose of the Study:

• To propose a novel high-capacity coverless information steganography technology.
• To enhance the data embedding capacity of CIS while maintaining stego-image quality.

Main Methods:

• Dividing cover images into blocks, with each block representing one bit of secret information.
• Retrieving and replacing image blocks from a database based on secret data to synthesize stego images.
• Implementing a double-level index structure to improve retrieval efficiency.

Main Results:

• The proposed method significantly increases embedding capacity compared to existing CIS techniques.
• Stego images generated exhibit high visual quality due to the use of similar natural image blocks.
• Experimental results validate the superior capacity and quality of the proposed approach.

Conclusions:

• The developed high-capacity CIS technology effectively addresses the limitations of previous methods.
• This advancement offers a promising solution for secure and efficient information hiding.
• The method provides a practical approach for transmitting secret information with improved capacity and visual fidelity.