Abstract:

We propose a reversible data hiding scheme based on histogram of difference image, which improves both embedding capacity and image quality after data embedding. The original image is firstly divided into blocks and scanned, and then differences between neighbor pixels are calculated. After that, the two peak points of the histogram of difference image are shifted bidirectionally to get the gap for data embedding. The data is preprocessed before it is embedded. The scheme makes full use of the similarity between neighbor pixels of natural images to increase both the number and the height of peak points of the histogram, thus improving the embedding capacity obviously. Besides, the preprocess of the information to be embedded makes the impact on data embedding smaller, and achieves embedded images of better quality.

Key words: reversible;data hiding;histogram of difference image;block