High-Capacity Reversible Data Hiding in Encrypted Images with Flexible Restoration.

Area of Science:

• Computer Science
• Information Security
• Image Processing

Background:

• Existing reversible data hiding in encrypted images (RDH-EI) methods offer either high capacity or processing flexibility.
• Previous methods have limitations, such as restricted processing order, hindering practical application.

Purpose of the Study:

• To develop a novel RDH-EI method with superior hiding capacity and unrestricted processing order.
• To enhance flexibility for users by removing constraints on data hiding and encryption sequences.

Main Methods:

• Proposed two efficient algorithms to maximize hiding capacity by improving pixel value prediction accuracy.
• Refined the embedding algorithm for enhanced performance.
• Achieved reversible data hiding in encrypted images without order restrictions.

Main Results:

• The proposed method achieves a record hiding capacity of 2.50 bpp on the BOWS-2 dataset.
• Demonstrated full flexibility in the processing order for both data hiding and encryption/decryption.
• Experimental results confirm the method's effectiveness in hiding capacity and marked-image quality.

Conclusions:

• The novel RDH-EI method significantly advances the field by offering both highest capacity and complete processing flexibility.
• The method provides enhanced user privileges through its unrestricted operational order.
• This research contributes a more practical and efficient solution for secure data embedding in encrypted images.