Collage Attack Research Articles

A semi-fragile image watermarking algorithm with two-stage detection

The ability against the collage attack of semi-fragile watermarking is improved by embedding the watermark of a block in other blocks, but the tamper detection performance is impaired under general...

A block-based watermarking scheme for image tamper detection and self-recovery

AbstractIn this paper, we present an effective block-based digital fragile watermarking scheme for image tamper detection and recovery. The proposed scheme embeds watermarks consisting of the authentication data and the recovery data into image blocks. It adopts parity check and the intensity-relation check to thwart various malicious attacks. In the tamper detection process, instead of independently testing the embedded authentication data of each block, we take the block-neighbourhood into account and utilize a hierarchical structure to determine the legitimacy of image blocks. Experimental results show that the proposed scheme can effectively resist collage attack, vector quantization (VQ) attack and constant-average attack, while sustaining superior accuracy of tamper localization. Furthermore, the results reveal that the tampered images can be successfully self-recovered with acceptable visual quality.

Fragile Watermarking Algorithm for JPEG Images Based on Neighborhood Comparison and its Performance Analysis

PDF HTML阅读 XML下载 导出引用 引用提醒 基于邻域比较的JPEG 脆弱水印算法及性能分析 DOI: 10.3724/SP.J.1001.2012.04169 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金(60970122, 61170226); 国家教育部博士点基金(20090184120021); 中央高校基本科研业务专项基金(SWJTU09CX039, SWJTU10CX09); 北京市“现代信息科学与网络技术”重点实验室基金; 铁道部“铁路信息科学与工程”开放实验室基金(XDXX1007) Fragile Watermarking Algorithm for JPEG Images Based on Neighborhood Comparison and its Performance Analysis Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:为提高篡改检测性能和协调安全性与不可见性之间的矛盾,提出一种利用邻域比较判定图像块真实性的JPEG 脆弱水印算法.该算法将原始图像分成8×8 的图像块,基于图像块保护DCT 系数生成的4 比特水印基于密钥随机嵌入到其他4 个图像块量化步长较小的DCT 系数最低位.通过比较该图像块与相应4 个水印嵌入块8 邻域中不一致图像块个数来判定该图像块的真实性,推导给出一般篡改和拼贴攻击下算法的虚/漏警率,并利用统计实验对理论分析结果进行验证.理论分析和实验统计结果表明,通过比较图像块与其相应水印嵌入块8邻域中不一致图像块个数能够提高篡改检测性能,在量化步长较小DCT 系数的最低位嵌入水印,解决了保护DCT 系数个数与不可见性之间的矛盾. Abstract:To improve the tamper detection performance and harmonize the conflict between security and invisibility, this paper proposes a fragile watermarking algorithm for JPEG images, in which the authenticity of image blocks is determined by neighborhood comparison. This scheme divides the original image into 8×8 image blocks. For each block, four bits watermarks are generated based on the DCT coefficients to be protected. Next, the watermarks are randomly embedded in the least significant bit (LSB) of DCT coefficients with smaller quantization step in other four blocks. The authenticity of each block is determined by comparison between the number of inconsistent image blocks in the eight-neighborhood of each block and its four corresponding mapping blocks. Then, this paper derives the probability of false acceptance and false rejection under general tampering and collage attack and validates the theoretical analysis results by statistical experiments. Theoretical analysis and statistical experiments show that comparing the number of inconsistent image blocks in the eight-neighborhood of each block with its four corresponding mapping blocks improves the tamper detection performance. Embedding watermarks in the LSB of DCT coefficients with less quantization step efficiently solves the conflict between the number of DCT coefficients to be protected and invisibility. 参考文献 相似文献 引证文献

A chaotic system based fragile watermarking scheme for image tamper detection

Abstract In the past few years, various fragile watermarking techniques have been proposed for image authentication and tamper detection. In this paper, a novel chaos based watermarking scheme for image authentication and tamper detection is proposed. Tamper localization and detection accuracy are two important aspects of the authentication watermarking schemes. Our scheme can detect any modification made to the image and can also indicate the specific locations that have been modified. To improve the security of the proposed scheme two chaotic maps are employed. Since chaotic maps are sensitive to initial values, the corresponding position relation between pixels in the watermarked image and the watermark get disturbed, which helps the watermarking scheme to withstand counterfeiting attacks. Initial values of the chaotic maps are used as secret keys in our scheme. The effectiveness of the proposed scheme is checked through a series of attacks. Experimental results demonstrate that the proposed scheme is not only secure but also achieves superior tamper detection and localization accuracy under different attacks. For instance in copy-and-paste attack and collage attack.

Authentication and recovery of an image by sharing and lattice-embedding

Based on sharing and lattice-embedding techniques, we present an authentication-recovery method for an image. The recovery data are shared among many shadows, then lattice-embedding is utilized to embed each shadow in the discrete cosine transform domain of an 8×8 block. The proposed method can resist certain content-preserving operations such as JPEG compression, Gaussian noise, and brightness adjustment, up to a tolerance level controlled by a quantization parameter value. The method can also resist certain security attacks such as a cut-and-paste attack, a collage attack, and a vector quantization attack. Compared with previous works, the proposed method has following major advantages and novelty: (1) the method does not require prediction of the tampering trace, and the tampered blocks are always recovered as long as the number of valid blocks reaches a threshold and (2) lattice-embedding yields smaller distortion than does parity-check quantization, and the latter was often used in reported works.

Digital image authentication and recovery: Employing integer transform based information embedding and extraction

Recently, several semi-fragile watermarking approaches with the additional capability of image recovery have been proposed. However, the security, robustness, and image recovery aspect of these approaches have certain shortcomings. In this paper, a novel semi-fragile watermarking framework using integer transform based information embedding and extraction is proposed, which allows accurate authentication and recovery of the image. It is based on integer wavelet transform with improved security against collage attack, enhanced robustness, and capability of producing better quality recovered image. Security is enhanced by correlating the to-be-embedded watermark with the approximation subband of wavelet transform. Similarly, no unprotected area is left for attacks on the image, either in spatial or transform domain. Robustness is enhanced by using the idea of embedding in largest coefficient inside a group and correlating it with the quantized version of the mean of the group. In particular, the recovery approach is improved by introducing lossless compression and BCH coding of the integer DCT based low-pass version of the cover image itself. Alteration sensitivity is improved compared to traditional block-based approaches and thus the proposed approach can concisely determine the regions where the integrity verification fails. Experimental comparisons with existing approaches validate the usefulness of the proposed multiple semi-fragile watermarking approach.

A neighborhood-characteristic-based detection model for statistical fragile watermarking with localization

Statistical fragile watermarking is capable of accurately locating tampered pixels and resisting the collage attack. However, the constraint of the tamper ratio may be too stringent. This paper proposes a neighborhood characteristic based detection model for statistical fragile watermarking to lift the constraints of the tampered area from 4% to 14% of the host image. The neighborhood characteristic is used to effectively decrease the probability of false rejection, while the low probability of false acceptance is guaranteed by selecting proper threshold. The tamper detection performance of the proposed detection model is analytical analyzed in the different conditions. Analytical and experimental results demonstrate that the neighborhood characteristic based detection model effectively reduce the total number of false decisions and detect the tampered pixels with high probability.

Adjacent-block based statistical detection method for self-embedding watermarking techniques

This paper proposes an adjacent-block based statistical detection method for self-embedding watermarking techniques to accurately identify the tampered blocks, and gives an analytical analysis of the tamper detection performance. In the proposed statistical detection method, we take all adjacent blocks of the test block and its mapping block into account and then utilize a statistic-based rule to verify the validity of image blocks. Analytical analysis and experimental results demonstrate that the proposed statistical detection method can identify the tampered blocks with a probability more than 98% even the tampered area is up to 70% of the host image. In addition, the proposed method outperforms conventional self-embedding fragile watermarking algorithms in tamper detection under collage attack and content-tampering attack.

A digital authentication watermarking scheme for JPEG images with superior localization and security

The drawbacks of the current authentication watermarking schemes for JPEG images, which are inferior localization and the security flaws, are firstly analyzed in this paper. Then, two counterferiting attacks are conducted on them. To overcome these drawbacks, a new digital authentication watermarking scheme for JPEG images with superior localization and security is proposed. Moreover, the probabilities of tamper detection and false detection are deduced under region tampering and collage attack separately. For each image block, the proposed scheme keeps four middle frequency points fixed to embed the watermark, and utilizes the rest of the DCT coefficients to generate 4 bits of watermark information. During the embedding process, each watermark bit is embedded in another image block that is selected by its corresponding secret key. Since four blocks are randomly selected for the watermark embedding of each block, the non-deterministic dependence among the image blocks is established so as to resist collage attack completely. At the receiver, according to judging of the extracted 4 bits of watermark information and the corresponding 9-neighbourhood system, the proposed scheme could discriminate whether the image block is tampered or not. Owing to the diminishing of false detection and the holding of tamper detection, we improve the accuracy of localization in the authentication process. Theoretic analysis and simulation results have proved that the proposed algorithm not only has superior localization, but also enhances the systematic security obviously.

A majority-voting based watermarking scheme for color image tamper detection and recovery

This paper presents a novel color image watermarking scheme for both tamper detection and tampered image recovery. The proposed scheme embeds watermarks consisting of the authentication data and the recovery data into image blocks. In the tamper detection process, instead of independently examining each embedded authentication data, we take all the authentication data embedded in an image into account and utilize a majority-voting technique to determine the legitimacy of image blocks. Experimental results show that the proposed scheme can effectively thwart collage attack and vector quantization (VQ) attack, while sustaining superior accuracy of tamper localization. Furthermore, the results reveal that the tampered images can be successfully recovered with acceptable visual quality.

Reversible watermarking resistant to cropping attack

A reversible digital watermarking scheme based on a blockwise difference expansion (DE) method is proposed here. The proposed scheme differs from previous ones in its robustness against cropping and collage attacks. In order to easily detect the correct cropped position for a cropped image, a locating pattern is embedded into the carrier image by a modified patchwork algorithm. Incurred overhead, payload, and authentication information are then collected and embedded into the carrier image by a blockwise DE method. Within the proposed scheme, image ID and block index also serve as parts of the inputs to the hash function. This endows the scheme with capability in resisting collage attacks. The experimental results show that the scheme can achieve a good robustness against cropping attacks as well as collage attacks.

Wavelet-based fragile watermarking scheme for image authentication

We propose a fragile watermarking scheme in the wavelet transform domain that is sensitive to all kinds of manipulations and has the ability to localize the tampered regions. To achieve high transparency (i.e., low embedding distortion) while providing protection to all coefficients, the embedder involves all the coefficients within a hierarchical neighborhood of each sparsely selected watermarkable coefficient during the watermark embedding process. The way the nonwatermarkable coefficients are involved in the embedding process is content-dependent and nondeterministic, which allows the proposed scheme to put up resistance to the so-called vector quantization attack, Holliman-Memon attack, collage attack, and transplantation attack.

Cryptanalysis of the Yeung–Mintzer fragile watermarking technique

The recent proliferation of digital multimedia content has raised concerns about authentication mechanisms for multimedia data. A number of authentication techniques based on digital watermarks have been proposed in the literature. In this paper we examine the security of the Yeung–Mintzer authentication watermarking technique and show that it is vulnerable to different types of impersonation and substitution attacks whereby an attacker is able to either create or modify images that would be considered authentic. We present two attacks. The first attack infers the secret watermark insertion function. This enables an attacker to embed a valid watermark in any image. The attack works without knowledge of the binary watermark inserted in the image, provided the attacker has access to a few images that have been watermarked with the same secret key (insertion function) and contain the same watermark. We show simulation results in which the watermark and the watermark insertion function can be mostly reconstructed in a few (1–5) minutes of computation, using as few as two images. The second attack we present, which we call the “collage attack” is a variation of the Holliman–Memon counterfeiting attack. The proposed variation does not require knowledge of the watermark logo and produces counterfeits of superior quality by means of a sophisticated dithering process. © 2002 SPIE and IS&T.