High-Quality and High-Capacity Data Hiding Based on Absolute Moment Block Truncation Coding

Abstract

Numerous images are transmitted over the Internet every day. However, for some sensitive images, such as personal medical images, public networks constitute an insecure environment. Watermarking methods are therefore essential for ensuring information security. Additionally, most digital transmitted images are compressed first so as to increase transmission efficiency. This paper presents a data hiding method for absolute moment block truncation coding (AMBTC)-compressed images. The goal of this method is to improve the Internet transmission efficiency by compressing the image and to ensure secure communication by embedding extra secret information into the compressed image at the same time. In the proposed method, the cover image is first classified into two types of blocks through a block classification scheme. Several embedding rules are proposed according to the block type, and an iteration-based halftoning method is integrated with AMBTC to optimize the image quality. Moreover, the blind decoding method is proposed wherein the secret data are extracted from the stego image itself. Experimental results showed that this method outperformed other state-of-the-art methods in terms of image quality and embedding capacity.