基于预测误差分类置乱的图像加密域可逆信息隐藏

为提高XU算法的隐藏容量和加密图像的安全性, 提出了一种基于预测误差分类置乱的加密域可逆 信息隐藏算法。首先根据XU的预测方法得到非采到样像素的预测误差,根据预测误差的取值范 围将所有非 采样像素分为可变像素和不变像素两类。对采样像素、可变像素和不变像素分类置乱后再异 或加密生成加 密图像,以提高加密图像的安全性。可变像素的低2位用于保存图像信息,剩余的6个高有效 位均可用于 隐藏信息,实现了一个可变像素嵌入多比特附加信息,提高了嵌入容量。实验结果表明,本 算法的加密方 法能有效抵抗COA唯密文攻击,且平滑图像的隐藏容量可以超过2比特每像素。     

基于Paillier加密的大容量双图像可逆信息隐藏

双图像可逆信息隐藏由于其具有更好的安全性、嵌入率和图像视觉质量,成为信息安全领域重要的研究方向.Bhardwaj等人提出了密文域上的双图像可逆信息隐藏算法,进一步提升了安全性,但是该算法嵌入秘密信息的数量有限.本文提出了一种新的嵌入策略,先将图像的每个像素分解成3个单元,并使用Paillier算法对其加密.根据改进的最...     

基于部分高位平面预测的图像加密域可逆信息隐藏

提出一种基于部分高位平面预测的图像加密域可逆 信息隐 藏算法。本算法利用自然图像高位平面相关性高的特点,根据像素高位n(2相似文献   

融合CFT和LSB的高容量可逆数据隐藏

针对可逆数据隐藏中图像质量和嵌入容量之间相互矛盾的问题,提出一种中心折叠技术与最低有效位替换相结合的可逆数据隐藏方法。该方法首先对原始图像中的像素进行位平面划分,以得到2个位平面;然后利用中心折叠技术将秘密数据折叠,并将折叠后的秘密数据嵌入到原始像素的最高有效位中,以生成2个隐秘像素;最后利用最低有效位替换将秘密数据嵌入到隐秘像素的最低有效位中,以进一步提高嵌入容量。实验结果表明,利用中心折叠技术与最低有效位替换来嵌入秘密数据,嵌入容量达到了1 572 778位,有效地提高了嵌入容量;当嵌入容量相同时,与嵌入秘密数据后的相关算法相比,图像的PSNR提高了约2dB,降低了图像失真,具有更好的不可感知性。     

基于分块最佳预测的可逆数据隐藏

为了提高嵌入算法的性 能,提出一种基于分块最佳预测和直方图平移的灰度图像可逆数据隐藏算法。根据嵌 入阈值,统计 每一图像块中4种预测方案的嵌入容量,选择最大容量对应的预测方案作为该图像块的最佳 预测方案。嵌 入算法充分利用像素值局部相关性,自适应地选择最佳预测方案,有效提高嵌入容量。实验 结果表明,本 文算法在保证图像质量的同时有效提高嵌入容量,算法的整体性能比其它同类算法更优。     

图像插值空间完全可逆可分离密文域信息隐藏算法

密文域可逆信息隐藏技术在医学、云服务、军事、商业等众多领域有着广泛应用,针对现有密文域信息隐藏算法的可逆性不能完全保证、嵌入率低、不能完全分离等不足,提出一种完全可逆可分离密文域信息隐藏算法,首先,给出了适合图像加密遍历矩阵所需满足的条件和构造方法,载体图像拥有者设置密钥1构造遍历矩阵,并对明文图像进行加密,然后将加密图像传送给信息嵌入者,信息嵌入者设置密钥2,以期望插值为目标,根据插值区间大小确定嵌入位数,再由差值修正因子和秘密信息共同确定最终插值,使最终插值最大限度接近期望插值,确保载密图像高质量,整个过程无附加信息、无数据溢出、且均可保证可逆性,密钥1拥有者和密钥2拥有者两种权限互不干涉,是完全可逆可分离算法,平均嵌入率可达到3 bit/pixel,通过与8种优秀算法的实验比较,表明算法在嵌入容量、可逆性、可分离性率等方面相比于对比算法均有一定优势.     

基于编码压缩和加密的图像可逆信息隐藏算法

提出一种编码压缩和加密的图像可逆信息隐藏算 法。计算载体像素预测值与其像素值的差值, 对差值进行哈夫曼编码压缩,通过压缩数据和随机数据加密重构图像,得到载体数据。将哈 夫曼编码的码 表和秘密信息隐藏在载体数据中,实现信息隐藏。在载密数据中提取码表数据和秘密信息, 对加密压缩数 据进行解密,结合码表和预测方法恢复原始图像。实验结果表明,本文算法具有较大的隐藏 容量,不仅能 正确提取秘密信息,还能无损恢复原始图像。     

基于重复压缩的密文图像可逆数据隐藏方法

为了提高密文图像上的可逆数据隐藏方法的性能,在加密前处理图像以获得数据嵌入空间。首先,分析了在解压缩分块上进行可逆嵌入的可行性;其次,计算了成功恢复解压缩分块的理论概率;最后,提出了基于解压缩分块的密文图像可逆数据隐藏算法,主要过程包括预处理、加密、数据嵌入、数据提取与图像恢复。从图像恢复错误率、嵌入容量和PSNR这3个方面与3种已有方法进行对比,表明所提方法实现了数据提取和图像解密在操作上的完全分离,且图像恢复错误率更低,嵌入容量更大,PSNR更高。     

基于Tabu搜索的彩色图像可逆数据隐藏算法

针对当前算法对彩色图像进行可逆隐藏时无法获取最优嵌入数据，存在综合性能差以及加密性能差的问题，提出基于Tabu搜索的彩色图像可逆数据隐藏算法，首先对彩色图像进行加密，确定嵌入的位置，利用Tabu搜索算法提取出最优嵌入秘密数据，在加密图像时进行秘密数据的嵌入，对秘密信息以及图像进行预处理；其次接收者利用自带的密钥对已经嵌入数据的加密图像进行解密，同时对图像进行翻转恢复以及信息提取，实现彩色图像可逆数据隐藏。实验结果表明，所提算法的综合性能高以及加密性较好。     

高安全可分离全位平面密文域可逆数据隐藏

针对图像在网络传输中的隐私信息泄露问题,提出了高安全可分离全位平面密文域可逆数据隐藏方案.重点研究如何保障原始图像和待隐藏数据安全,提出了分块分类置乱算法及遍历矩阵加密算法以实现原始图像加密,采用Hilbert曲线加密实现待嵌入数据加密,采用基于全位平面置乱技术,并分析讨论位平面特点,将其分为连续块和非连续块,进而使用像素预测方法,以实现秘钥可分离的可逆数据隐藏.实验结果表明,与现有同类算法相比,该方案具有较强的综合性能,首先,安全性高,本文分别从秘钥空间、秘钥敏感性、相关性、NPCR、UACI和信息熵等指标分析其安全性;其次,具有可逆性,提取数据与原始数据的NCC为1,恢复后图像与原始图像的PSNR为无穷大,能够完全无损的恢复图像、提取数据;且含密图像质量高,平均PSNR高达64.64 dB,远远高于其他文献;再次,容量高,理论最高容量为6 bpp,实际平均容量也达到2.5 bpp;此外,本方案具有鲁棒性,能够有效抵抗椒盐噪声、剪切和高斯白噪声攻击,且实现了秘钥可分离.     

An efficient high-capacity reversible data hiding scheme for encrypted images

Reversible data hiding in encrypted images is an effective technique to embed information in encrypted domain, without knowing the original content of the image or the encryption key. In this paper, a high-capacity reversible data hiding scheme for encrypted images based on MSB (most significant bit) prediction is proposed. Since the prediction is not always accurate, it is necessary to identify the prediction error and store this information in the location map. The stream cipher is then used to encrypt the original image directly. During the data hiding phase, up to three MSBs of each available pixel in the encrypted image are substituted by the bits of the secret message. At the receiving end, the embedded data can be extracted without any errors and the original image can be perfectly reconstructed by utilizing MSB prediction. Experimental results show that the scheme can achieve higher embedding capacity than most related methods.     

基于图像插值的大容量可逆水印算法

提出一种基于图像插值的大容量可逆水印算法 。首先,对输入图像进行下采样 处理,利用某种图像插值方法对下采样生成的图像进行插值放大,得到待嵌入水印信号的载 体图像;然后,对载体 图像进行分块,得到每一分块4个基准像素的最大值和最小值,之后计算每一个非基准像素 分别与最大值和最小值 差值的绝对值,根据自适应选定的差值,计算每一个非基准像素能嵌入的最大水印位数;最 后,从待嵌入的水印信 号中将每一个非基准像素能嵌入的位数转换为十进制数,并将此数修改像素值,完成水印 信号的嵌入。大量的仿 真实验结果表明,本文算法不会出现像素值溢出现象,能实现可逆数据隐藏;与相似的基于 图像插值的可逆水印算法 相比,该算法的嵌入率(ER,embedding rate)更高;在相同 的ER条件下,本文算法的性能更好。     

Reversible data hiding in encrypted images based on absolute mean difference of multiple neighboring pixels

Recently, with the development of cloud computing, more and more secret data are stored in cloud. Reversible data hiding in encrypted images is a technique that makes contribution to cloud data management in privacy preserving and data security. In previous works, Zhang and Hong presented two reversible dada hiding methods in encrypted images, respectively. However, Zhang’s work neglected the pixels in the borders of image blocks, and Hong et al.’s research only considered two adjacent pixels of each pixel. In addition, their works only considered that all image blocks are embedded into additional data. In this paper, we propose a novel method of evaluating the complexity of image blocks, which considers multiple neighboring pixels according to the locations of different pixels. Furthermore, data embedding ratio is considered. Experiments show that this novel method can reduce average extracted-bit error rate when the block size is appropriate.     

High-capacity reversible data hiding in encrypted images based on adaptive block encoding

This paper proposes a new high-capacity reversible data hiding scheme in encrypted images. The content owner first divides the cover image into blocks. Then, the block permutation and the bitwise stream cipher processes are applied to encrypt the image. Upon receiving the encrypted image, the data hider analyzes the image blocks and adaptively decides an optimal block-type labeling strategy. Based on the adaptive block encoding, the image is compressed to vacate the spare room, and the secret data are encrypted and embedded into the spare space. According to the granted authority, the receiver can restore the cover image, extract the secret data, or do both. Experimental results show that the embedding capacity of the proposed scheme outperforms state-of-the-art schemes. In addition, security level and robustness of the proposed scheme are also investigated.     

High-capacity reversible data hiding in encrypted image based on specific encryption process

This paper proposes a novel reversible data hiding method in encrypted images based on specific encryption process. In the proposed specific encryption algorithm, the stream cipher and prediction error are combined to vacate room for data embedding. After that, a permutation operation is performed on the encrypted image to improve the security. In the embedding process, we can embed a large amount of secret data in the encrypted image by pixel value expansion because most of the pixel values are less than 128 by the specific encryption process. At the receiver end, the encrypted image can be recovered from the marked encrypted image without knowing the secret data. Therefore, even if the recipient only has the encryption key, the original image will be perfectly recovered. If the recipient only has the data-hiding key, the secret data will be extracted. And if the recipient has both keys, the original image and the secret data are both available. The proposed method achieves a higher embedding capacity than that of methods based on vacating room after encryption. It does not require the image owner to perform reversible data hiding techniques on the original image, which is more convenient than methods based on reserving room before encryption. Experimental results demonstrate that the proposed method outperforms other state-of-the-art methods.     

On the multi-level embedding of crypto-image reversible data hiding

Crypto-space reversible image steganography has attracted increasing attention, given its ability to embed authentication information without revealing the image content. This paper presents an efficient reversible data hiding scheme for crypto-images: a block predictor is applied to compute prediction errors, then an adaptive block mapping algorithm is utilized to compress them whose amplitudes are within a small threshold, finally, this strategy can be applied in a multi-level manner to achieve a higher embedding capacity. Due to the correlations among adjacent pixels in the block, images can be sufficiently compressed to reserve abundant space for additional data embedding. Different from the prior arts, the compression code of the image is fully encrypted. Experimental results verify that the embedded data and original image can be perfectly recovered, the security is higher compared with the state-of-the-arts, and a significant improvement in the average embedding rate is achieved on two large-scale image datasets.     

基于滑动窗口和对数函数的高纹理图像可逆数据隐藏

可逆数据隐藏技术利用可逆变换将数据嵌入原始宿主图像中,在图像接收端正确提取出所嵌入数据的同时,能够有效地恢复原始数据,在图像信息隐藏技术中具有较好的应用.本文分析了差值扩展嵌入数据前后单个像素的变化和像素对间大小关系的变化,从而说明滑动窗口在提高图像嵌入比特率方面的有效性.同时对于差值扩展算法中扩展差给图像带来的较大失真,利用对数函数对差值进行修改,从而降低数据嵌入后对原始宿主图像造成的失真.实验结果表明,滑动嵌入方式能够有效解决单层嵌入比特率低于0.5bpp的缺陷,理论上单层图像嵌入比特率高达1bpp.同时,和Lou算法比较表明,修改后对数函数嵌入方式在提高嵌入比特率的同时,有效地提高了嵌入数据后图像的质量．