全体变长编码映射的JPEG可逆信息隐藏

目的 JPEG(joint photographic experts group)作为一种广泛使用的图像格式,对其进行可逆信息隐藏有实际应用价值。大多数以JPEG图像为载体的可逆信息隐藏方案会导致图像质量降低和文件膨胀。由于在JPEG比特流中,并没有使用较多的变长编码(variable-length code, VLC),因此以未使用的VLC替换已使用的VLC可以实现秘密信息的无损嵌入,但这类方法的嵌入容量有限,且会导致文件膨胀。为了实现更大的嵌入容量并更好地控制文件膨胀,本文提出了新的全体VLC映射方案。方法 首先,重排序原始比特流中的行程长度/幅值大小(run/size value, RSV),获得去除编码冗余的载体;然后,引入中间VLC的概念,根据VLC频数分布,确定使文件膨胀大小相对于嵌入载荷最小的最优中间VLC映射模型;接着,通过计算模拟嵌入下的文件膨胀大小,确定构建最优中间VLC映射所需的嵌入VLC和中间VLC集合;最后,根据最优中间VLC映射关系修改定义哈夫曼表和JPEG比特流实现秘密信息的嵌入。结果 实验在USC-SIPI数据库上与基于DCT(discrete cosi...     

Lossless data hiding using bit-depth embedding for JPEG2000 compressed bit-stream

We have proposed a reversible information hiding for binary images. In this paper, we present a Iossless data hiding method for JPEG2000 compressed data based on the reversible information hiding. In JPEG2000 compression, wavelet coefficients of an image are quantized, therefore, the least significant bit plane （LSB） can be extracted. The proposed method recovers the quantized wavelet coefficients of cover images from Stego images. To realize this, we embed not only secret data and the JBIG2 bit-stream of a part of the LSB plane but also the bit-depth of the quantized coefficients on some code-blocks. Experimental results demonstrate the feasibility of application of the proposed method to image alteration detection for JPEG2000 compressed data.     

一种基于排序的JPEG码流无损水印算法

提出了一种基于排序的直接在JPEG码流中嵌入水印的算法,该方法在保证嵌完水印后图像无失真的条件下提高了嵌入容量.根据对JPEG图像中可变长度码使用情况的统计分析,通过将一幅图像中没有使用过的可变长度码映射为使用过的可变长度码来嵌入水印.在建立映射关系之前,首先对码流中出现过的可变长度码依据其在码漉中出现的频率进行排序,然后使用排序后的结果建立映射关系,从而提高可变长度码的利用率,进而提高嵌入容量.在水印嵌入过程中,根据相应的映射关系和水印信息将码流中出现的可变长度码替换为映射的可变长度码.分析和实验结果表明,这种方法能够实现较高容量的水印嵌入,并且嵌完水印后图像无失真.     

分块自适应JPEG图像数据隐藏算法*

为提高隐秘JPEG图像视觉质量与隐藏容量,在修改JPEG缺省量化表的前提下,针对JPEG图像提出一种自适应数据隐藏算法。该算法首先根据图像分块视觉特性确定用于数据隐藏的图像分块,然后应用LSB替换方法修改DCT域量化后AC系数以嵌入秘密数据。实验结果表明,该算法在保证较好透明性的同时,显著提高了JPEG图像隐藏容量,与其他同类算法相比,隐藏容量提高约21%。该方案可为互联网环境图像实时通信提供安全保障手段。     

A reversible data hiding scheme using complementary embedding strategy

Obtaining good visual quality and high hiding capacity with reversible data hiding systems is a technically challenging problem. In this paper, we propose a simple reversible data hiding scheme that uses a complementary hiding strategy. The proposed method embeds one secret bit horizontally and vertically into one cover pixel of a grayscale cover image by decreasing odd-valued pixels and increasing even-valued pixels by one. Experimental results show that the hiding capacity measured by bit per pixel (bpp) of the proposed scheme is at least 1.21 bpp with a PSNR (peak signal-to-noise ratio) value greater than 52 dB for all standard test images. Especially in the case of four-layer embedding, the PSNR value of the proposed method is still greater than 51 dB at a hiding capacity of about 5 bpp for all standard test images. In addition, the proposed method is quite simple because it primarily uses additions and subtractions. These results indicate that the proposed scheme is superior to many existing reversible data hiding schemes introduced in the literature.     

选择排序的DCT系数对JPEG图像的可逆数据隐藏

JPEG图像压缩算法可以为使用者提供良好的压缩性能,改善图像文件重建质量,在图像和视频处理领域有着广泛的应用价值。 提出了一种可行且有效的对JPEG图像进行可逆信息隐藏的算法。在该算法中,JPEG图像中所有的8×8块中量化的DCT系数重新排列成新的矩阵,纵列为每个块的系数值,横列为同频率下的系数值。对相同频率下的系数进行模拟嵌入比特位,优先选择失真小的频率下的系数嵌入信息,直到嵌入完秘密比特流信息,同时在嵌入秘密信息时根据解码矩阵减少了无效的比特流扩展。实验结果表明,该算法在嵌入同等数量的比特流的情形下能够得到更好的JPEG图像视觉质量和更少的图像比特流扩展。     

A high capacity data hiding scheme for binary images based on block patterns

This paper proposes a high capacity data hiding scheme for binary images based on block patterns, which can facilitate the authentication and annotation of scanned images. The scheme proposes block patterns for a 2 × 2 block to enforce specific block-based relationship in order to embed a significant amount of data without causing noticeable artifacts. In addition, two kinds of matching pair (MP) methods, internal adjustment MP and external adjustment MP, are designed to decrease the embedding changes. Shuffling is applied before embedding to reduce the distortion and improve the security. Experimental results show that the proposed scheme gives a significantly improved embedding capacity than previous approaches in the same level of embedding distortion. We also analyze the perceptual impact and discuss the robustness and security issues.     

Reversible data hiding exploiting spatial correlation between sub-sampled images

Reversible data hiding enables host media to be restored from marked media without any loss of host information. Since this reversibility helps to make right decision during image analysis, it is highly desired in quality-sensitive imagery where even the minimal distortion introduced by embedding data is unacceptable. In this paper, we propose a reversible data hiding method that modifies the difference histogram between sub-sampled images. It exploits the high spatial correlation inherent in neighboring pixels to achieve high capacity and imperceptible embedding. On various test images including 16-bit images, we demonstrate the validity of our proposed method by comparing to other existing reversible data hiding algorithms. Experimental results support that our method provides high embedding capacity while keeping the distortions at a low level.     

基于JPEG图像的模块化可逆信息隐藏方法

当前的可逆信息隐藏方法为了寻求更好的嵌入性能,通常会基于给定的图像内容对修改模式和嵌入参数作出自适应的调整。然而,通过细化自适应程度或扩大解空间来寻找更优解时,会造成计算复杂度高、时间成本难以承受等问题。为此,提出了一种适用于JPEG图像的模块化可逆嵌入方法来提高自适应寻优的效率。通过比较不同情况下最优解的嵌入性能,对原有的解空间进行优化、筛选,从而生成一个适用于不同图像的通用修改模式集合。每一个修改模式被定义为在多直方图修改框架下的最优嵌入点集合。在嵌入时,为给定的图像内容自适应地从预设的解集中选定合适的修改模式。实验在USC-SIPI数据集上与五个具有代表性的方法进行了比较。相比于同类算法,所提算法可将峰值信噪比提升0.03～1.81 dB。对于文件大小扩展,所提算法的性能结果可比两个经典方法分别减少12.4%和5.1%。实验结果表明,相比于主流经典方法,该方法在含密图像质量和文件大小扩展方面有更好的性能表现,并能以较低的计算复杂度取得与最近的高效方法相近的自适应嵌入效果。     

JPEG图象中的无损信息隐藏

一般的信息隐藏方法均会使载体数据有轻微的损伤,如能够无误地恢复载体数据,则具有更广泛的应用价值,为此提出了一种针对JPEG图象的无损信息隐藏方案.该方案是利用JPEG压缩后的冗余空间,将秘密信息嵌入在不为0的DCT系数上,具体的嵌入位置由密钥决定;同时,由一个原始值为0的DCT系数承载被替换的原始数据,而接收方根据密钥不仅可以提取出秘密信息,而且可以无误差地恢复原始图象.实验表明,载体图象的质量因子越小,嵌入率就越高,而且秘密信息对干扰有一定的稳健性.     

JPEG比特流加密域大容量可逆数据隐藏

兼顾加密JPEG图像的隐藏容量和安全性,提出一种JPEG比特流加密域可逆数据隐藏新方法。该算法设计了一种块间置乱与块内加密相结合的JPEG比特流加密方法,不仅实现对图像块的伪随机置乱,还实现了熵编码块的霍夫曼编码和扩展位的全加密,降低信息泄露可能性的同时,提高了算法抵抗唯密文攻击的能力。同时,该算法生成的加密JPEG比特流与JPEG解码标准兼容,解码得到的加密图像类似随机噪声且与原始图像大小相同,所有图像块熵编码都可以用来隐藏附加信息,有效解决了隐藏容量与安全性之间的矛盾。对比分析了算法的安全性、文件大小和隐藏容量等性能。实验仿真结果表明本文算法能有效抵抗唯密文攻击,隐藏容量是现有最新同类算法的4倍以上。     

基于直方图对的JPEG图像无损数据隐藏

提出一种基于直方图对的JPEG图像无损数据隐藏方法。该方法通过调整直方图,在JPEG图像的量化后DCT中频系数中嵌入隐藏数据。同时,能够在不需要原始图像的情况下对隐藏数据进行盲提取并无损恢复图像数据。通过设置2个阈值来选择调整的直方图对和进行调整的DCT系数块,该方法能够在嵌入大数据量的同时依然保持较好的视觉效果。     

基于差值扩展的音频无损信息隐藏算法

在Tian算法的基础上,提出了一种基于音频的无损信息隐藏算法。该算法首先对载体音频进行溢出预处理和采样点分类,然后利用差值扩展方法,将隐秘信息嵌入到扩展差值的LSB位。在提取时,利用无损解码技术得到位置映射表,再提取出隐秘信息后,载体音频可以实现无损恢复。仿真结果证明,算法能获得较高的隐藏容量,并能有效地保证含秘音频的感知质量。     

A lossless robust data hiding scheme

This paper presents a lossless robust data hiding scheme. The original cover image can be recovered without any distortion after the hidden data have been extracted if the stego-image remains intact, and on the other hand, the hidden data can still be extracted correctly if the stego-image goes through JPEG compression to some extent. The proposed scheme divides a cover image into a number of non-overlapping blocks and calculates the arithmetic difference of each block. Bits are embedded into blocks by shifting the arithmetic difference values. The shift quantity and shifting rule are fixed for all blocks, and reversibility is achieved. Furthermore, owing to the separation of bit-0-zone and bit-1-zone as well as the particularity of arithmetic difference, minor alteration applying to the stego-image generated by non-malicious attacks such as JPEG compression will not cause the bit-0-zone and the bit-1-zone to overlap, and robustness is achieved. Experimental results show that, compared with previous works, the performance of the proposed scheme is significantly improved.     

基于预测熵的JPEG图像无损数据隐藏

针对数据隐藏中的子块选择问题,提出一种基于预测熵的JPEG图像无损数据隐藏方法。利用直方图对法预测JPEG图像DCT系数块的熵,选择熵小的子块,并在中低频系数中嵌入数据。该方法可实现嵌入数据的盲提取和图像数据的无损恢复,且无需记录嵌入数据的子块位置。实验结果表明,与其他方法相比,该方法获得图像的峰值信噪比较高,数据隐藏性能较好。     

密文域可逆信息隐藏综述

可逆信息隐藏是信息隐藏技术的新兴研究方向,密文域可逆信息隐藏作为加密域信号处理技术与信息隐藏技术的重要结合点,对于数据处理过程中的信息安全可以起到双重保险的作用,尤其随着云服务的推广,密文域可逆信息隐藏是实现云环境下隐私保护的研究重点之一。针对当前密文域可逆信息隐藏技术的技术要求,介绍了该技术的产生发展背景,指出并分析了当前的技术难点,通过对各种类型代表性算法的研究,对密文域可逆信息隐藏技术进行了系统的分类,分析了不同嵌入方式的技术特点、实现框架与应用上的局限性。最后,结合密文域可逆信息隐藏的技术需求与难点,提出几点该领域未来的热点方向。     

An improved VLC mapping method with parameter optimization for reversible data hiding in JPEG bitstream

Multimedia Tools and Applications - The typical reversible data hiding (RDH) method for JPEG bitstream is conducted by building the mapping between the used VLCs and the unused VLCs, and will not...     

Lossless compression and information hiding in images

This paper presents an image lossless compression and information-hiding schemes based on the same methodology. The methodology presented here is based on the known SCAN formal language for data accessing and processing. In particular, the compression part produces a lossless compression ratio of 1.88 for the standard Lenna, while the hiding part is able to embeds digital information at 12.5% of the size of the original image. Results from various images are also provided.     

Hiding data in compressive sensed measurements: A conditionally reversible data hiding scheme for compressively sensed measurements

Most of the real-world signals we encounter in real-life applications have low information content. In other words, these signals can be well approximated by sparse signals in a proper basis. Compressive sensing framework uses this fact and attempts to represent signals by using far fewer measurements as compared to conventional acquisition systems. While the CS acquisition is linear, the reconstruction of the signal from its sparse samples is nonlinear and complex. The sparse nature of the signal allows enough room for some additional data sequence to be inserted and exactly recovered along with the reconstructed signal. In this study, we propose to linearly embed and hide data in compressively sensed signals and nonlinearly reconstruct both of them using a deflationary approach. We investigate the embedding capacity as a function of signal sparsity and signal compression, as well as the noise sensitivity of the proposed algorithm.