关键词: 可逆数据隐藏, 图像对比度增强, 嵌入率, 中值点, 峰值

Abstract: A new reversible data hiding algorithm is proposed for low embedding rate and complexity process in traditional algorithm. To increase the information hiding rate, the highest bins at both sides of the median point in image histogram are chosen to be split for data embedding, respectively. Multiple pairs of histogram bins are chosen for data embedding and the pair of the median point is chosen at last. The median point can be located directly after embedding, so that reversible data embedding and image recovered can be achieved, in addition, there is no need for the replacement of the least significant bit which requires a simple computation. The proposed algorithm is tested on two image sets. The obtained experimental results are compared with the existing algorithm for data embedding and  three MATLAB functions for image contrast enhancement, which can evaluate the capacity of embedding and the quality of image contrast enhancement. The numerical results show that the proposed algorithm outperforms the existing algorithm in hiding rate and image quality preservation, and besides, the capacity of data embedding is greatly improved.

Key words: reversible data hiding, image contrast enhancement, embedding rate, median point, histogram peak