Self-sanitization of digital images using steganography

Abstract

Sanitization of an image is a process where certain areas of an image are removed to keep the contents safe from unauthorised viewers. Image sanitization is often required by authorities, for example law enforcement or in legal cases, when the image contains sensitive material that should not be shown to the general public. This paper proposes a system for the self-sanitization of a digital image using information hiding, specifically image steganography, techniques to hide part of the image within the image itself. The proposed self-sanitization system allows for the removal of a specific part of the image and then uses Least Significant Bit (LSB) steganography to embed the sanitized part of the image within the rest of the image, making it unnecessary to store the sanitized and unsanitized versions of the image separately. The self-sanitization system includes a method for reducing the size of the embedded information in an attempt to make the information more difficult to detect. Experimental results show that the proposed self-sanitization system is undetectable to visual and statistical analysis techniques.