Fragile Watermarking Method Research Articles

High Capacity and Reversible Fragile Watermarking Method for Medical Image Authentication and Patient Data Hiding.

The exchange of medical images and patient data over the internet has attracted considerable attention in the past decade, driven by advancements in communication and health services. However, transferring confidential data through insecure channels, such as the internet, exposes it to potential manipulations and attacks. To ensure the authenticity of medical images while concealing patient data within them, this paper introduces a high-capacity and reversible fragile watermarking model in which an authentication watermark is initially generated from the cover image and merged with the patient's information, photo, and medical report to form the global watermark. This watermark is subsequently encrypted using the chaotic Chen system technique, enhancing the model's security and ensuring patient data confidentiality. The cover image then undergoes a Discrete Fourier Transform (DFT) and the encrypted watermark is inserted into the frequency coefficients using a new embedding technique. The experimental results demonstrate that the proposed method achieves great watermarked image quality, with a PSNR exceeding 113dB and an SSIM close to 1, while maintaining a high embedding capacity of 3 BPP (Bits Per Pixel) and offering perfect reversibility. Furthermore, the proposed model demonstrates high sensitivity to attacks, successfully detecting tampering in all 18 tested attacks, and achieves nearly perfect watermark extraction accuracy, with a Bit Error Rate (BER) of 0.0004%. This high watermark extraction accuracy is crucial in our situation where patient data need to be retrieved from the watermarked images with almost no alteration.

A novel reversible fragile watermarking method in DWT domain for tamper localization and digital image authentication

Medical images are extremely valuable and sensitive data because of their significance in research, diagnosis, and treatment. However, the transmission of medical images over an unsecured network can lead to security issues such as modification, removal, copying, and unauthorized access. For this reason, the protection of medical information is of great importance. This paper proposes a novel reversible fragile digital watermarking method for tamper localization and authenticity and integrity protection in medical images. In the proposed method, the host image is firstly divided into 8×8 non-overlapped blocks. Then the image is transformed to the frequency domain by applying a Discrete Wavelet Transform, and the watermark information is embedded. Finally, the image is converted from the frequency domain to the spatial domain using an inverse Discrete Wavelet Transform. During this transformation, an intelligent optimization technique is used to correct the rounding errors and obtain the watermarked image with the highest level of imperceptibility. The experimental results demonstrate that the proposed method offers a watermarked image with high imperceptibility, extracts the host image lossless during the watermark extraction phase, and performs tamper localization with high precision.

A novel Frei‐Chen based fragile watermarking method for authentication of an image

AbstractIn recent years, the protection of the intellectual property rights of digital media has become a considerable issue. Especially using digital image editing tools has made it very easy and fast to manipulate images. Therefore, manipulation detection of digital images has become a necessity. This article presents a novel Frei‐Chen based self‐embedding fragile watermarking technique implemented to blocks for image manipulate detection. The block key and the Frei‐Chen based block feature are calculated from the non‐overlapping image blocks of size . Exclusive‐OR operations are applied to the Frei‐Chen based block feature and the block key. After, a nine bit block authentication key is generated from the Frei‐Chen based block feature and the block key. Then the generated authentication key is embedded in the least significant bits of each block. Experimental results prove the effectiveness of the proposed method through the detection of the various attacks and obtain the excellent visual quality of watermarked images. Also, the results demonstrate that the proposed method detects all of the manipulated areas plainly.

An Optimized Fragile Image Watermarking Method for Tamper Detection and Recovery Using SPIHT and Reed-Solomon Coding

An Optimized Fragile Image Watermarking Method for Tamper Detection and Recovery Using SPIHT and Reed-Solomon Coding

A novel pixel-wise authentication-based self-embedding fragile watermarking method

Self-embedding fragile watermarking algorithms can perform detection of the manipulated areas as well as recovery of these detected areas. Most of the self-embedding fragile watermarking algorithms are performed block-wise authentication approach. However, entire block is marked as tampered in case one of the pixels in the block is detected as manipulated. This situation decreases the accuracy rate of the authentication process especially against pixel-based attacks such as salt and paper noise adding. Therefore, we present a novel pixel-wise authentication-based self-embedding fragile watermarking method for manipulation detection and recovery. In this proposed method, reference image is divided into four main blocks. Then, each main block is subdivided into $$2\times 4$$ or $$4\times 2$$ sized blocks according to block type determined using recovery quality. Recovery bits of each main block generated from sub-blocks are spreaded into the two main blocks in the other half of the image. For each pixel, two authentication bits are generated using the six most significant bits of the pixel with two pixel position bits and then embedded into the first and second least significant bits of the pixel. In experimental results, pixel-based attacks are applied to the images to demonstrate the success of the presented method. Also, performance of the presented method has been evaluated by applying different size of cropping attacks to the watermarked images. Experimental results show that the proposed method satisfactory detect and recover the manipulated areas.

Optical fragile watermarking based on visual cryptography and QR code

An optical fragile watermarking method is proposed based on visual cryptography and QR code for image authentication and tamper detection. On the one hand, the original image is transformed into a QR watermark image to improve the watermark hiding capacity. On the other hand, the visual cryptography and optical phase coding are fused to encrypt the watermark image to enhance system security. The feasibility, vulnerability and imperceptibility of the proposed scheme are tested through a series of attacks and tampering. The simulation results show that the proposed method can not only have good imperceptibility, but also achieve high detection performance under different attacks and tampering.

Detection and Recovery of Higher Tampered Images Using Novel Feature and Compression Strategy

Due to the availability of powerful image-editing software and the growing amount of multimedia data that is transmitted via the Internet, integrity verifications and confidentiality of the data are becoming critical issues. However, currently, the accuracy of detecting and the recovery capability of the tampered images by the existing methods through watermarking strategy is still not at the required level, especially at a higher tampered rate. This paper proposes a new blind and fragile watermarking method to detect tampering and better recovery of tampered images. To improve the quality of both the watermarked and the recovered images, a new feature extraction scheme is introduced which will produce a short but comprehensive recovery code using a new compression strategy. If a block in the image tampers, the proposed embedded feature allows the original data to be extracted for recovery. To overcome tamper coincidence, every block’s watermarked data contains not only the recovery code belonging to the block itself but also its neighbor’s data as a second layer of recovery. Various size blocks were investigated to see the performance and compare their efficiency for recovering an image after different tampering rates. The test showed the smaller block sizes may be more suitable for locating tampering, where the bigger ones are more suitable when the tampering rate is higher. The bigger block sizes in the proposed method can recover an image even after a 60% tampering rate with high quality (more than 31 dB). The experimental results prove that the proposed method can have better efficiency for detecting tampering, and recovery of the original image, compared to the relevant existing methods.

A novel triple recovery information embedding approach for self-embedded digital image watermarking

Image tamper detection and recovery has become an important issue in recent years. In order to detect and recover high tampering rated images, this paper presents a novel self-embedded fragile watermarking method with triple recovery information embedding approach. In this proposed method host image is divided into sixteen main blocks. Four partner blocks are selected from main blocks as a partner group using Look-Up table which is constructed for recovery against high tampering rated images. Each partner block is divided into 4 × 4 blocks. Recovery data of each partner block is generated from the mean values of the 4 × 4 blocks. Then, triple recovery information for each partner block is constructed by combining recovery data of the three other partner blocks. After the generation of the recovery information, each partner block is divided into 16 × 16 blocks. Then, these blocks are divided into four 8 × 8 sub-blocks. Recovery bits for each partner block are embedded into the first and second least significant bits (LSBs) of the first three sub-blocks. It means that triple copies of recovery information for each partner block are embedded into three other blocks in the image, which provides triple chance for recovery of the tampered areas. On the other hand, authentication information is generated from the pixels of the 16 × 16 recovery information embedded image blocks by using MD5 hash function. This authentication information is embedded into the quarter part of each 16 × 16 block by using LSB substitution. The performance of the proposed method has been demonstrated by applying different size of cropping attacks to the different areas of the watermarked images. Experimental results show that the proposed method satisfactory recovers up to 75% tampering rated images.

Fragile watermarking for image authentication using BRINT and ELM

Privacy and security concerns regarding digital information have been increasing with advancements in multimedia and network technologies. Digital images are an integral component of online-distributed content, which plays a crucial role in forming public perceptions and opinions. They also play a major role in sensitive areas, such as law and defense. Any attempt to tamper with them is, therefore, a serious issue. One common approach to this problem is fragile image watermarking, which is used to ensure the authenticity of digital content. In this paper, a new fragile watermarking method for the authentication of digital images is proposed based on a binary rotation invariant and noise tolerant (BRINT) local texture descriptor and an extreme learning machine (ELM). BRINT is used to generate and retrieve the watermark in both the embedding and extraction procedures. In parallel, ELM is used in both procedures to learn and recover any tampered areas. The experimental results showed that the proposed scheme does not degrade image quality, allows for tamper detection, and has a recovery ability comparable with state-of-the-art fragile and semi-fragile watermarking schemes. Moreover, the proposed scheme has been validated as a fragile watermarking method with the potential to detect and locate modifications in digital images, such as copy-paste forgery, JPEG compression, and noise addition. This method is useful in sensitive fields, like defense, law, and journalism, in which decision-making based on digital visual information is necessary, to ensure that an image is authentic and has not been tampered with.

A self-recovery watermarking scheme based on block truncation coding and quantum chaos map

To take into account the invisibility, recovery quality, detection ability, and security, a new digital image fragile watermarking method based on block truncation coding (BTC) and quantum chaos map is proposed. In this method generates the authentication watermark for each 4 × 4 block and generates the recovery watermark for each 2 × 2 block by block truncation coding. For each block, the block truncation coding is used to classify the image blocks into smooth blocks and rough blocks. For different blocks, recovery data can be generated by allocating fewer bits to the smooth blocks and more bits to the rough blocks to encoding the block content. Quantum chaos map is used to generate the block mapping sequence for embedding recovery watermark to improve the shortcoming of watermarking such as small keyspace and low security. The experimental results show that the proposed scheme improves the quality of watermarked and recovered images. Additionally, this approach achieves higher security than the existing methods, under different attacks, such as general tampering, collage attack, content-only, and a hybrid attack.

Exploiting Self-Embedding Fragile Watermarking Method for Image Tamper Detection and Recovery

Exploiting Self-Embedding Fragile Watermarking Method for Image Tamper Detection and Recovery

Block-based fuzzy-image authentication method

Fragile watermarking methods have been widely used for image authentication. A novel image-authentication method based on fuzzy coding is presented in this work. This method is a block-based method and it consists of watermark generation, watermark embedding, watermark extraction, tamper detection, and image recovery phases. First, the cover image is divided into nonoverlapping blocks. In the watermark-generation step, fuzzy sets and fuzzy coding are used. To generate fuzzy sets, three threshold points are selected from a histogram of the cover image and fuzzy sets are created by using these threshold points. Memberships of pixels are calculated to generate features. Fuzzy coding is used to generate the watermark. The watermark-embedding function uses ±1 data hiding function for each block. Therefore, high visual quality is achieved. The generated watermark is compared with the extracted watermark in the tamper-detection phase. Finally, a new image-recovery algorithm is proposed for recovering tampered areas. To evaluate the proposed method, visual quality, tamper detection ability, image recovery capability, and computational complexity were used. The experimental results clearly indicated that the proposed method was a success.

A novel hash function based fragile watermarking method for image integrity

In recent years, tampering and altering of digital images have become easier with the rapid development of computer technologies such as digital image editing tools. Therefore, verification of image integrity and tamper detection of digital images have become a great challenge. Fragile watermarking is the most widely used method for protecting the integrity and content authenticity of the image. In this paper, by using SHA-256 hash function, a novel block based fragile watermark embedding and tamper detection method is proposed. In watermark embedding phase, host image is divided into 32 × 32 non-overlapped blocks. Each 32 × 32 block is then divided into four 16 × 16 nonoverlapped sub-blocks. The entire hash value of the first three sub-blocks is generated as a watermark using SHA-256 hash function. The generated 256-bit binary watermark is embedded into the least significant bits (LSBs) of the fourth sub-block and watermarked image is obtained. In tamper detection phase, the detection of tampered block has been performed by comparing the hash value obtained from the three sub-blocks with the extracted watermark from the fourth sub-block of the watermarked image. The performance of the proposed method has been evaluated by applying linear and nonlinear attacks to the different regions of the watermarked images. Experimental results show that the proposed method detects all the tampered regions of the attacked images and high visual quality of watermarked images has been obtained.

Quantum-Dot Cellular Automata based Fragile Watermarking Method for Tamper Detection using Chaos

Quantum-Dot Cellular Automata based Fragile Watermarking Method for Tamper Detection using Chaos

2D Vector Map Fragile Watermarking with Region Location

Locating the original region of tampered features is a challenging task for existing 2D vector map fragile watermarking methods. This article presents a 2D vector map fragile watermarking framework that locates not only the current but also the original region of tampered feature groups. In particular, we propose dividing the features of the host vector map into groups, and embedding a watermark consisting of location-bits and check-bits into each group at the sender side. At the receiver side, by comparing the extracted and calculated check-bits, one can identify tampered groups and locate their current regions. Then the location-bits extracted from the mapping groups are used to indicate the original regions of the tampered groups. To demonstrate and analyze the applicability of this framework, we instantiate it by proposing a simulated annealing (SA)-based group division method, a group mapping method, a minimum encasing rectangle (MER) based location-bits generation method and a check-bits generation method, and use an existing reversible data hiding method for watermark embedding. The experimental results show that the proposed framework can locate all the regions influenced by tampering, and the SA-based group division method can get a better region location ability.

Fragile watermarking tamper detection via bilinear fuzzy relation equations

We present a fragile color image watermarking based on the greatest solution of a bilinear fuzzy relation equation. The original image is coded with fuzzy transforms and divided in sub-images of sizes 2 × 2 called blocks. The watermark is applied on these blocks. A pre-processing phase is used to determine the best compression rate for the coding process. We test this scheme in tamper detection analysis on a sample of color images having different sizes. The results show that the proposed algorithm is better than that one obtained by using our previous method. Furthermore comparisons with various block-based fragile watermarking methods are made in our tests.

A Self-Recovery Fragile Image Watermarking with Variable Watermark Capacity

Currently, the watermark capacity of most self-recovery fragile image watermarking schemes is fixed. That means for smooth regions and texture regions, the length of watermark information is always the same. However, it is impractical since more recovery information is needed for the recovery of texture regions. In this paper, a self-recovery fragile image watermarking with variable watermark capacity is proposed. Based on the characteristic of singular value decomposition (SVD), a new block classification method is introduced. The image blocks are classified into smooth blocks and texture blocks. For smooth blocks, the average pixel values are adopted as the recovery information to recover the tampered blocks, while for texture blocks, the quantized and coded DCT coefficients are adopted as the recovery information. After encrypted by binary pseudo-random sequence, the recovery watermark of each block is embedded into its mapping block. In the detection side, the three-level detection mechanism is applied to detect and locate the tampered regions. The experimental results prove that the proposed method achieves good tamper detection results, and the recovered image has better image quality than other self-recovery fragile watermarking methods.

A probabilistic image authentication method based on chaos

Fragile watermarking methods have been used as active image authentication methods. These methods must have capabilities like high capacity, high visual quality, high image authentication ability and image recovery capability. Many of the fragile watermarking methods suggested in the literature do not provide all of these capabilities. In this article, a new probabilistic image authentication method with high capacity, high visual quality, high image authenticity ability and image recovery capability is proposed. Chaotic pseudo random number generators, a new watermark generation network which similar to neural network, modulo based watermark embedding functions, modulo based watermark extraction functions, tamper detection algorithm and perceptual hash based image recovery algorithm are utilized for creating a new probabilistic image authentication method in this article. The proposed method is a block based authentication method and 3 × 3 size of overlapping neighborhood blocks are used in this method. The proposed watermark generation network uses symmetric pixels as inputs and weights to generate predicted pixel. In this step, modulo operator and random numbers are used for calculating embeddable value. Owing to chaotic random number generator, the proposed method gains probabilistic and nonlinear structure. To generate random number, logistic map is used as random number generator in the proposed image watermarking method. Then, a modulo based watermark embedding function is used for embedding embeddable value (generated watermark). In the watermark extraction step, modulo operator is used. If the predicted value differs from the extracted value, tamper detection is performed. Otherwise, image authentication is success. A new image recovery algorithm is proposed in this method. This algorithm provides image recovery for tampered areas with high visual quality. The proposed image watermarking method can authenticate grayscale and color images. The experimental results demonstrated that, the proposed method has high payload capacity, high visual quality and high image authentication ability.

Authenticity verification of audio signals based on fragile watermarking for audio forensics

Abstract This paper presents a new fragile watermarking method for digital audio authenticity for audio forensics purposes. The aim is to verify if an audio proof has been tampered and to locate the segments where the signal was modified. Our proposal is based on an embedding process of a text that is encoded through OVSF (Orthogonal Variable Spreading Factor) codes and spread into the entire signal using automatic adjustment. Several tests were performed in order to quantify the accuracy and the reliability of the tampering detection against four classical attacks (cropping, replacement, additive noise and amplitude reduction) by using kappa index, sensitivity and specificity. It was demonstrated that even if a small number of samples is modified, the system correctly labels the audio proof as manipulated, and locates both the start and end of the manipulation; the kappa index (reliability) is around 0.96, sensitivity is always 1, and specificity is around 0.995. The proposed algorithm could be used as a decision support tool for audio forensics verification purposes, that allows to identify if an audio proof has been modified, and the time segments in which it has been modified.

Fragile Watermarking for Image Authentication Using the Characteristic of SVD

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.