Reversibility improved lossless data hiding

Recently, lossless data hiding has attracted increasing interests. As a reversible watermark scheme, the host media and hidden data should be recovered without distortion. A latest lossless data hiding technique based on image blocking and block classification has achieved good performance for image authentication. However, this method cannot always fully restore all the blocks of host images and watermarks. For this purpose, we propose an improved algorithm, which is characterized by two aspects. First, a block skipping scheme (BSS) is developed for the host blocks selection to embed watermark; secondly, the embedding level is modified by a novel parameter model to guarantee that the host blocks can be recovered without distortion as well as the embedded data. Extensive experiments conducted on standard grayscale images, medical images, and color images have demonstrated the effectiveness of the improved lossless data hiding scheme.