A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> Semifragile watermarking techniques aim to prevent tam- pering and fraudulent use of modified images. A semifragile water- mark monitors the integrity of the content of the image but not its numerical representation. Therefore, the watermark is designed so that the integrity is proven if the content of the image has not been tampered with, despite some mild processing on the image. How- ever, if parts of the image are replaced with the wrong key or are heavily processed, the watermark information should indicate evi- dence of forgery. We compare the performance of eight semifragile watermarking algorithms in terms of their miss probability under forgery attack, and in terms of false alarm probability under nonma- licious signal processing operations that preserve the content and quality of the image. We propose desiderata for semifragile water- marking algorithms and indicate the promising algorithms among existing ones. © 2004 SPIE and IS&T. (DOI: 10.1117/1.1633285) <s> BIB001 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> This paper proposes a novel fragile watermarking scheme capable of perfectly recovering the original image from its tampered version. In the scheme, a tailor-made watermark consisting of reference-bits and check-bits is embedded into the host image using a lossless data hiding method. On the receiver side, by comparing the extracted and calculated check-bits, one can identify the tampered image-blocks. Then, the reliable reference-bits extracted from other blocks are used to exactly reconstruct the original image. Although content replacement may destroy a portion of the embedded watermark data, as long as the tampered area is not too extensive, the original image information can be restored without any error. <s> BIB002 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> This paper presents a semi-fragile watermarking technique capable of verifying the authenticity and recovery of the image. The proposed approach has the capability to accurately detect and differentiate modifications applied on the watermarked image. Alteration sensitivity has been improved compared to previous approaches and it can concisely determine the region of the watermarked image where the integrity verification fails. Semi-fragility makes the proposed method tolerant against JPEG lossy compression and other acceptable modifications but sensitive to malicious attacks such as cutting and pasting. The exact low pass version of the image is recovered by using the lossless compression (Huffman coding). Simulation results demonstrate that the alteration sensitivity of the proposed authentication scheme is much better compared to the previous approaches. <s> BIB003 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> In this paper, we propose a scheme can be divided into two parts: one is about robust embedding of dual visual watermarks using DWT and Singular Value Decomposition (SVD), the other part is about tamper detection and self-recovery algorithm of color image. We stress on the latter part. Dual visual watermarks are original image watermark which is color scale image the same as original image and ownership watermark which is gray scale image, respectively. Both of them are embedded into original image using DWT-SVD to prove robustness. For recovery signal embedding, luminance signal and chrominance signal of original image were embedded into surplus chrominance space of original image using matrix transpose replacement embedding method. For watermark extraction scheme: firstly, threshold value would be set to find tampered region. Then we extract the recovery signals to construct recovery information. Lastly we replace tampered regions with recovery information based on threshold value. We can extract the original image watermark and ownership watermark from recovery image. Experiment demonstrates that the proposed scheme is robust to a wide range of attacks and is good at tampered detection as well as self- recovery of tampered images. <s> BIB004 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> A novel semi-fragile watermarking scheme in DWT domain for image authentication and tamper localization is proposed in this paper. The proposed scheme extracts content-based image features from the approximation subband in the wavelet domain to generate the watermark. Then the watermark is embedded into the middle frequency subband in the wavelet domain. For image authentication and tamper localization, the extracted watermark is compared with the extracted content-based image feature matrix. Experimental results show that the proposed scheme is robust to common content-preserving image processing (such as lossy JPEG compression, noise-adding), while it is fragile to malicious tamper in images. In addition, the proposed scheme can detect the tamper location accurately. <s> BIB005 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> This paper proposes two novel self-embedding watermarking schemes based upon a reference sharing mechanism, in which the watermark to be embedded is a reference derived from the original principal content in different regions and shared by these regions for content restoration. After identifying tampered blocks, both the reference data and the original content in the reserved area are used to recover the principal content in the tampered area. By using the first scheme, the original data in five most significant bit layers of a cover image can be recovered and the original watermarked image can also be retrieved when the content replacement is not too extensive. In the second scheme, the host content is decomposed into three levels, and the reference sharing methods with different restoration capabilities are employed to protect the data at different levels. Therefore, the lower the tampering rate, the more levels of content data are recovered, and the better the quality of restored results. <s> BIB006 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> In this paper, we propose a novel self-recovery watermarking scheme based on dual-redundant-ring structure (DRRS). All blocks of target image form a ring in a manner that the watermark of an image block is hidden in 1-LSB (least significant bit) of its next block N"1, and the copy of this watermark is embedded into 2-LSB of another block whose position is determined by the position of N"1. The validity of test image block is determined by comparing the number of inconsistent blocks in the block-neighborhood with that of its mapping block. Other detection result is generated in the same way comparing test block with copy block of its next block. The fusion of two detection marks improves tamper detection accuracy, while two copies of watermark provide a second chance for tamper recovery. Experimental results demonstrate that the proposed algorithm is superior to the state of the art of tamper detection and tamper recovery and could keep high security strength. <s> BIB007 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> In this paper, we present a new fragile watermarking method aimed at providing improved tampering localisation and self-recovery capabilities. First, a secure block-wise mechanism, resilient to cropping, is used to localise distorted blocks of pixels. Subsequently, the tampering localisation accuracy is refined by means of an iterative pixel-wise mechanism, which estimates the original watermarked pixels in altered regions. Extensive tests, using a large data-set, are presented to show to what extent the size of the tampered area influences the performance of our method. Moreover, results show that the proposed scheme compares favourably with a method presented in recent literature, in terms of tampering localisation and self-recovery performance. In fact, we show that our method is capable of partially reconstructing a cover image when 5% of its total number of pixels has been cropped. <s> BIB008 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> Digital Watermarking is a technique to embed additional data in digital images, without affecting the original image quality. It has become a useful tool for copyright protection, content authentication and steganography. Least Significant Bit is a commonly used technique in digital image watermarking. It is straight forward to understand and implement, and is widely used in many watermarking algorithms. A common problem of spatial LSB implementation is that a usual image compression can render watermark useless. In this paper we propose an alternative watermarking technique based on spatial LSB modification. It is robust against moderate JPEG compression, while keeping all the features of LSB. <s> BIB009 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> Due to the wide variety of attacks and the difficulties of developing an accurate statistical model of host features, the structure of the watermark detector is derived by considering a simplified channel model. In this paper, we present a fragile watermarking based on block-mapping mechanism which can perfectly recover the host image from its tampered version by generating a reference data. By investigating characteristics of watermark detector, we make an effective analysis such as fragility against robustness measure and distinguish its property. In particular, we derive a watermark detector structure with simplified channel model which focuses on the error probability versus watermark-to-noise-ratio curve and describes a design by calculating the performance of technique, where attacks are either absent or as noise addition. <s> BIB010 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> Abstract To take invisibility and restoration quality into account, this paper proposes an alterable-capacity watermarking scheme. For each block of size 8 × 8 pixels, the alterable-length code is generated based on the roughness of it. The alterable-length watermark generated by the alterable-length code is divided into three parts and embedded in other three blocks based on the secret key. The authenticity of each block is determined by comparing the watermark reconstructed by the block content and the corresponding extracted watermark. To improve the quality of recovered images, two copies of the significant-code of each block are embedded in different blocks and the image inpainting method is adopted to recover the tampered blocks whose significant-code embedded in other blocks is destroyed. The alterable-payload watermark preserves adequate information of image blocks especially for texture images with as few bits as possible and takes into account invisibility, security and restoration quality. Experimental results demonstrate that the proposed scheme improves the quality of watermarked and reconstructed images and is resilient to the known forgery attacks. <s> BIB011 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> In this paper, we present the performance analysis of a self-recovery fragile watermarking scheme using block-neighbor- hood tamper characterization. This method uses a pseudorandom sequence to generate the nonlinear block-mapping and employs an optimized neighborhood characterization method to detect the tampering. Performance of the proposed method and its resistance to malicious attacks are analyzed. We also investigate three optimization strategies that will further improve the quality of tamper localization and recovery. Simulation results demonstrate that the proposed method allows image recovery with an acceptable visual quality (peak signal-to-noise ratio (PSNR) as 25 dB) up to 60% tampering. <s> BIB012 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> This paper proposes a fragile image watermarking scheme with recover ability based on local binary pattern (LBP). The local binary pattern operator is mostly used to extract localized spatial features for texture analysis, image classification, and pattern recognition. According to spatial relations of a natural image, a local binary pattern can be utilized to represent the localized relations of a pixel with its neighborhood. Each pixel measured by the LBP operator can be obtained its own local binary pattern as representation of local spatial relations. The proposed scheme utilizes the LBP operator to generate authentication data which are embedded into each image block with 3 × 3 pixels size for tamper detection and recovery. The recovery information is obtained by calculating the mean value of each image block, and then the mean value is converted into a binary string which is embedded into eight neighboring pixels' LSBs of each image block for image recovering. From the experimental results, the proposed scheme has efficient tamper detection, better image quality and recovering ability than Zhang and Shih's LBP based watermarking scheme. <s> BIB013 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> Protection of medical images using watermarking is an imperative area of research. In telemedicine, medical images are exchanged between distant places through unsecure networks like internet for diagnosis purpose. During this transfer, medical images may be tampered intentionally or accidentally. The medical practitioner has to check the integrity of Region of Interest (ROI) in the received medical image before making any diagnostic decisions. In this paper, we are developing a novel fragile and block based medical image watermarking technique for producing high quality watermarked medical images, verifying the integrity of ROI, detecting accurately the tampered blocks inside ROI using both average and variance of blocks and recovering the original ROI with zero loss. In the proposed method, the medical image is segmented into three sets of pixels: ROI pixels, Region of Non Interest (RONI) pixels and border pixels. Then, authentication data and information of ROI are embedded in border pixels. Recovery data of ROI is embedded into RONI. Results of experiments conducted on number of medical images reveal that proposed method produces high quality watermarked medical images, identifies the presence of tampers inside ROI of watermarked medical images with 100% accuracy and recovers the original ROI without any loss. <s> BIB014 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> This paper proposes a semi-fragile digital watermarking scheme for image tamper localization and self-recovery. Firstly, the authentication watermark is generated for tampered area localization. After that, for content recovery, the recovery watermark is calculated from high frequency band with redundancy free. Then, for the two type of watermarks, the DWT-based watermark embedding method makes our proposed scheme tolerable against friendly manipulations. Even some parts of the watermarked image are tampered and the corresponding embedded information are missing, we can still recover the image from the untouched area based on the localization results and compressive sensing. Moreover, the encryption algorithm based on chaotic function guarantees the safety of our two type of watermarks. Extensive experiments demonstrate the effectiveness of the proposed scheme, which is sensitive against malicious tamper and robust to some incidental manipulations (e.g. JPEG compression, slight noise addition, brightness/contract adjustment and format conversion). <s> BIB015 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> Abstract The art of secretly hiding and communicating information has gained immense importance in the last two decades due to the advances in generation, storage, and communication technology of digital content. Watermarking is one of the promising solutions for tamper detection and protection of digital content. However, watermarking can cause damage to the sensitive information present in the cover work. Therefore, at the receiving end, the exact recovery of cover work may not be possible. Additionally, there exist certain applications that may not tolerate even small distortions in cover work prior to the downstream processing. In such applications, reversible watermarking instead of conventional watermarking is employed. Reversible watermarking of digital content allows full extraction of the watermark along with the complete restoration of the cover work. For the last few years, reversible watermarking techniques are gaining popularity because of its increasing applications in some important and sensitive areas, i.e., military communication, healthcare, and law-enforcement. Due to the rapid evolution of reversible watermarking techniques, a latest review of recent research in this field is highly desirable. In this survey, the performances of different reversible watermarking schemes are discussed on the basis of various characteristics of watermarking. However, the major focus of this survey is on prediction-error expansion based reversible watermarking techniques, whereby the secret information is hidden in the prediction domain through error expansion. Comparison of the different reversible watermarking techniques is provided in tabular form, and an analysis is carried out. Additionally, experimental comparison of some of the recent reversible watermarking techniques, both in terms of watermarking properties and computational time, is provided on a dataset of 300 images. Future directions are also provided for this potentially important field of watermarking. <s> BIB016 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> This paper describes an image tamper detection and recovery method based on self-embedding dual watermarking. The watermark in the proposed method is a down-sampled version of an original image (cover image). Two identical watermarks are then decomposed into bit planes and embedded into the least-significant bit (LSB) plane of the cover image. This dual watermarking strategy ensures a robust performance in image tamper detection and recovery. Moreover, since the bit planes of the two identical watermarks are arranged in center-point-symmetric manner, image information is spread uniformly. This makes it possible to recover large area of tampering, such as, left, right, upper, or lower half of the cover image. Experimental results show that the proposed method is remarkably effective for detecting and recovering local image tampering, such as, image collage. <s> BIB017 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> Abstract To address issues of image authenticity verification and integrity protection, a fragile watermarking method for stereo image authentication is proposed with stereo matching technique. According to stereo matching of left and right images, non-overlapping blocks of left image are classified into non-matchable and matchable ones. Right image blocks and non-matchable blocks of left image are categorized into smooth, texture and complex blocks considering their roughness. Then, the corresponding alterable-length watermark is computed based on the results of block classification, and the destroyed blocks are recovered by using the corresponding alterable-length watermark. Besides, matchable tampered blocks of left image are recovered with the matched contents in right image. A detection technique with the part of alterable-length watermark is used to increase accuracy of tamper localization at the receiver. The disparity can be used to recover the tampered matchable block. Therefore, the quality of watermarked images is improved because of low embedding capacity. Additionally, the alterable-capacity watermark provides suitable information for smoother images with fewer bits and we obtain high quality restoration. Experimental results show that the proposed method can not only localize the tampered regions precisely but also recover the tampered regions with higher quality compared with the state-of-the-art methods. <s> BIB018 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> Utilize relationships of singular values to extract content-dependent watermark.Merge relationships of singular values to choose adaptive quantizer for each block.Apply adaptive quantization to embed secure watermark in the wavelet domain.Define a 3-level authentication process to detect authenticity and prove tampering.Use five measures to compensate misclassification and capture distortions. This paper presents a singular-value-based semi-fragile watermarking scheme for image content authentication. The proposed scheme generates secure watermark by performing a logical operation on content-dependent watermark generated by a singular-value-based sequence and content-independent watermark generated by a private-key-based sequence. It next employs the adaptive quantization method to embed secure watermark in approximation subband of each 4i?4 block to generate the watermarked image. The watermark extraction process then extracts watermark using the parity of quantization results from the probe image. The authentication process starts with regenerating secure watermark following the same process. It then constructs error maps to compute five authentication measures and performs a three-level process to authenticate image content and localize tampered areas. Extensive experimental results show that the proposed scheme outperforms five peer schemes and its two variant systems and is capable of identifying intentional tampering, incidental modification, and localizing tampered regions under mild to severe content-preserving modifications. <s> BIB019 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> DCT based effective self-recoverable fragile watermarking scheme is presented.This scheme has extreme localization and restoration capability.The blocking artifacts negligible because of using the small blocks of size 2×2.Two levels hierarchical tampered detection mechanisms are used for tampered block detection. This paper presents a Discrete Cosine Transformation (DCT) based effective self-recoverable fragile watermarking scheme. For each 2 × 2 non-overlapping block, two authentication bits, and ten recovery bits are generated from the five most significant bits (MSBs) of pixels. Authentication bits are embedded in the three least significant bits (LSBs) of the block itself while recovery bits are embedded in the three LSBs of the corresponding mapped block. The proposed watermarking scheme is also effective because the authentication of each block is based on two levels hierarchical tampered detection mechanisms. So the detection of tampered block can be ensured with high probability. The experimental results demonstrate that the proposed scheme not only outperforms high-quality restoration effectively, but also removes the blocking artifacts and improves the accuracy of tamper localization due to the use of very small size blocks, smoothing function and two levels tampering detection mechanisms. <s> BIB020 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> Digital image authentication has become a hot topic in the last few years. In this paper, a pixel-based fragile watermarking method is presented for image tamper identification and localization. By analyzing the left and right singular matrices of SVD, it is found that the matrix product between the first column of the left singular matrix and the transposition of the first column in the right singular matrix is closely related to the image texture features. Based on this characteristic, a binary watermark consisting of image texture information is generated and inserted into the least significant bit (LSB) of the original host image. To improve the security of the presented algorithm, the Arnold transform is applied twice in the watermark embedding process. Experimental results indicate that the proposed watermarking algorithm has high security and perceptual invisibility. Moreover, it can detect and locate the tampered region effectively for various malicious attacks. <s> BIB021 </s> A recent survey of self-embedding fragile watermarking scheme for image authentication with recovery capability <s> Introduction <s> With the popularity of network and the continuous development of multimedia technology, saving of network bandwidth and copyright protection of multimedia content have gradually attracted people’s attention. The fragile watermark for integrity authentication of image data and protection of copyright has become a hotspot. In the storage and transmission process, image data must be compressed to save network bandwidth. As a result, semi-fragile watermarking techniques, which can be used to distinguish common image processing operations from malicious tampering, are emerging. In this paper, semi-fragile watermarking algorithms for image authentication are surveyed. The basic principles and characteristics about semi-fragile watermarking algorithms are introduced, and several kinds of attack behaviors are also included. Aiming at several typical image-authentication algorithms, advantages and disadvantages are analyzed, and evaluation indexes of various algorithms are compared. Finally, we analyze the key points and difficulties in the study on semi-fragile watermarking algorithms, and the direction about future development is prospected. <s> BIB022
Currently, the availability of image processing technology is highly diverse, thus an image content becomes easily manipulated by irresponsible parties. Replacement of content is very harmful to the owner especially when it comes to legal cases BIB020 . Therefore, research on detection and localisation of tampered images is an important issue. One approach that is widely used is the technique of digital watermarking. This is a technique of inserting secret information or image's information into an original image prior to sending. The original image is the image where the confidential information is inserted, while the secret information is a watermark  BIB013 BIB003 . The watermark component selection is done by considering the purpose of the watermarking technique. In general, the watermark used for image authentication and recovery uses two watermarks, which are bit authentication and bit recovery. For image recovery, bit recovery is selected from the image feature, usually from the original image compression form. When the watermark used is generated from the original image, it is known as the self-embedding watermarking scheme  BIB017 BIB006   . In general, digital watermarking techniques can be categorised as robust watermarking, fragile watermarking and semi-fragile watermarking. Watermark is specifically selected to be able to withstand deliberate or intentional manipulation, in this case belonging to a strong watermarking category, commonly used for copyright and verification of the image BIB009 BIB004 . In the fragile watermarking technique that is being used for the authentication process, the embedded watermark vulnerability indicates that there are modifications either intentionally or unintentionally  BIB013  BIB018 BIB010  BIB011 BIB012 BIB002 BIB021 BIB007 BIB008 BIB005 BIB014   . Meanwhile, in semi-fragile watermarking techniques, there are common image processing methods, such as JPEG compression, scaling, sharpening; and tidy against deliberate manipulations, such as content modified by false information, then the watermark is designed to be able to resist a variety of non-heretical attacks BIB003 BIB005  BIB019 BIB015 BIB001 BIB022 . For the purposes of authentication, fragile watermarking schemes can be categorised into two main categories as fragile watermarking pixel-wise schemes BIB018 BIB021 BIB007 BIB008  and fragile watermarking block-wise schemes BIB020 BIB013 BIB003 BIB004  BIB002 BIB005 BIB014  . In the pixel-wise fragile watermarking scheme, the watermark information is generated from the grey pixel value of the host and inserted into the host pixel. Meanwhile, in the fragile watermarking scheme of block-wise, the original image is subdivided into blocks. Each sub-block has watermark information and is authenticated with a watermark retrieval successfully embedded in it. If the watermarked image is modified, the watermark of a sub-block is not successfully retrieved, and then the sub-block is identified as a damaged or incorrect block. The fragile nature for authentication applications is also used in reversible data hiding techniques. According to BIB016 , most reversible watermarking techniques are fragile and allow for extracting watermarks along with the complete restoration of the original image. Reversible data hiding methods for uncompressed images have been discussed in [32] , where there are two criteria to show their performances, i.e. imperceptibility and planting capacity. Imperceptibility is a measure of similarity between watermarked and covers images. Meanwhile, the capacity of embedding is a measure of the maximum number of bits of information that can be pinned on the cover image. The least significant bit (LSB) method in data hiding has simplicity, easy detection and high embedding capabilities   . The LSB method, therefore, is generally preferred for embedding watermarks on fragile image watermarking. To facilitate the understanding of fragile watermarking, in addition to the discussion of conceptual understanding, this article also explains the comparison of methods ranging from insertion, extraction and recovery results. At the end, the analysis of the results of the evaluation is also described by selecting four methods that represent spatial domains to experiment with many tampered images. A block diagram in Fig. 1 provides a brief overview of the self-embedding fragile watermarking scheme for image authentication. The organisation of this paper survey is described in Section 2, which is broken into the following subsections. Section 2.1 of this paper explains an overview of the basic principles of self-embedding fragile watermarking. Section 2.2 shows the mechanisms of selection, generation and method of watermark insertion. Section 2.3 describes the comparison and discussion based on two domains. Section 2.4 discusses the experimental results of four watermarking techniques. Finally, the conclusion is given in Section 3.