基于图像块像素差的大容量无损信息隐藏算法

为使提取嵌入的秘密信息后能无损恢复原始载体图像，提出一种基于图像块相邻像素差的大容量无损信息隐藏算法。将原始载体图像进行分块，并按一定顺序扫描图像块得到一系列像素序列，通过计算每个序列中相邻像素的差值得到差值直方图，从中选择2个最大峰值点将秘密信息嵌入。实验结果表明，与其他无损嵌入算法相比，该算法在保证较好不可见性的情况下，信息嵌入容量较大，峰值信噪比较高。

High-capacity Lossless Information Hiding Algorithm Based on Pixel Difference of Image Block

A high-capacity lossless information hiding algorithm based on adjacent pixel differences of image block is proposed,which can recover the original image in lossless way after the hidden data are extracted from the stego image.It divides a cover image into a number of non-overlapping blocks,and sequences of pixels are obtained by scanning each image block in a given order.Pixel difference histograms are obtained by calculating adjacent pixel differences in each sequence.And the two maximal peak points in each pixel difference histogram are used to embed secret data.Experimental results show that compared with other lossless data hiding algorithms,the proposed algorithm can achieve large data hiding capacity and high PSNR while keeping image quality of the stego image high.