A New Fragile Watermarking Scheme and Its Security Evaluation

This paper presents an objective MPEG-2 video quality measurement method based on fragile digital image watermarking. Based on the DWT-based watermarking scheme, this paper presents a fragile digital video watermarking scheme that can work as an automatic quality monitoring system. We embed watermark in the DWT domain of the I-frames of an original video, and the DWT coefficients for embedding are carefully selected so that the degradation of the watermark can reflect the degradation of the video quality. This scheme can track the change of the PSNR value and the Watson JND value. The Watson perceptual model is taken into account to weight the quality measurement according to the human visual system. The evaluations demonstrate the effectiveness of the proposed scheme against MPEG-2 compression and noise pollution

For traditional fragile watermarking schemes, isolated-block tamper which will destroy the minutiae of the fingerprint image can hardly be efficiently detected. In this paper, we propose a multi-block dependency based fragile watermarking scheme to overcome this shortcoming. The images are split into image blocks with size of 8 × 8; a 64-bit watermark is generated for each image block, and then equally partitioned into eight parts. Each part of the watermark is embedded into another image block which is selected by the corresponding secret key. Theoretic analysis and experimental results demonstrate that the proposed method not only can detect and localize the isolated-block tamper on fingerprint images with high detection probability and low false detection probability, but also enhances the systematic security obviously.

It is a common practice in transform-domain fragile watermarking schemes for authentication purposes to watermark some selected transform coefficients so as to minimise embedding distortion. The author points out that leaving most of the coefficients unmarked results in a wide-open security gap for attacks to be mounted on them. A fragile watermarking scheme is proposed to implicitly watermark all the coefficients by registering the zero-valued coefficients with a key-generated binary sequence to create the watermark and involving the unwatermarkable coefficients during the embedding process of the embeddable ones. Non-deterministic dependence is established by involving some of the unwatermarkable coefficients selected according to the watermark from a nine-neighbourhood system in order to thwart different attacks, such as cover-up, vector quantisation and transplantation. No hashing is needed in establishing the non-deterministic dependence.

Fragile watermarking is designed to protect content integrity of digital data, meaning to detect any change in the content as well as localize areas that have been changed. In this paper, we propose a fragile watermarking scheme, which embeds dual watermarks (one is naturally fragile and the other is actually robust) in JPEG-2000 compressed images with ROI (region of interest) selection. In this scheme, the fragile watermark is embedded in ROI coefficients at the first decomposition layer, while the robust watermark embedded in ROB (region of backgrounds) coefficients at the third decomposition layer. The combinational working of them is not only capable of detecting malicious changes precisely and flexibly but also estimating the degree of alteration to discriminate intended attacks from unintended ones (e.g., such normal image processing as compression, low-pass filtering, sharpening, etc). Experiments show that our functionally fragile watermarking scheme is scalable in view of detecting attack's intension as well as accuracy in localizing the tampered areas.

The wide use of digital speech recorders becomes a serious matter when they are involved in assisting with court rulings. How to distinguish if a recorded content is valid or not becomes a life-or-death question. In light of this concern, least significant bits (LSB) of excitation signals would be used as fragile watermarks in the hybrid speech vocoder. In addition, a location-variable content-dependent watermark generating mechanism is proposed. Such location-variable content-based watermark would allow users to detect where in the recording the content is being replaced, inserted, or deleted. Lastly, an attempt is done to store partial reconstruction data in the LSBs of excitation signals in the G.723.1 speech codec, so that the original speech content may be reconstructed after counterfeited. The proposed system is demonstrated to be a reliable system, with test results showing that a recording with watermarks has a perceptual evaluation of speech quality (PESQ) value down 0.2, while the accuracy in detecting faked regions can be up to 97.45%.

This paper presents a new technique for copyright protection and content authentication of satellite images. The novelty in the presented approach consists in designing a hybrid Discrete Wavelet Transform (DWT), Discrete Cosine Transform (DCT) and hash function based digital image watermarking. In this study, two watermarks are embedded in the cover image called robust copyright watermark and fragile authentication watermark. The robust watermark is embedded in hybrid frequency and wavelet domain by applying DWT and DCT respectively. Such two steps embedding allows the proposed approach to provide better imperceptibility in harmony with the human visual system and offers higher robustness against signal processing attacks. Subsequently, the fragile watermark is embedded in a spatial domain using the hash function approach. The proposed hybrid watermarking technique has been tested on DubaiSat-2 images with 1 meter resolution. The experimental results show that the proposed method is robust against JPEG compression, rotation and resizing attacks. In addition, the multi-watermarked image has a good transparency and the fragile watermark is sensitive to any tampering.

We developed an efficient and secure image sanitizing scheme that enables integrity check and authentication of a sanitized image. Sanitizing is to delete or conceal sensitive data such as national secrets or personal information in digital images/documents. With a typical digital signature or digital watermarking scheme, a sanitized image cannot be authenticated because the integrity of the content is broken when it is sanitized. Our image sanitizing scheme solves this problem by combining a digital signature, digital watermarking and error correction technique with Reed-Solomon (RS) code. In addition, due to the RS encoding, we can realize the lightweight image sanitizing with small signature size, which is quite significant for the practical implementation. Furthermore, we investigate the security of our image sanitizing scheme. Considering the security requirements for image sanitizing, our scheme turned out to be quite effective to safely release a sensitive image to the public. The detailed explanation of our image sanitizing scheme and its security evaluation are given in this paper.

According to the fragile watermarking theory and insecure computer network, the integrity authentication scheme of biometric image based on singular value decomposition (SVD) is proposed for remote users via insecure computer network. We make good use of singular values of singular value decomposition (SVD) of biometric image to check the integrity of biometric image. To make authentication data, the singular values are changed to the binary bits using modular arithmetic. The binary bits of authentication data are embedded into the least significant bit (LSB) of the original biometric image. The pixels to be changed are randomly selected in the original biometric image. The advantages of this scheme are that 1) we can detect any modification of watermarked biometric image; 2) the quality of watermarked biometric image is very high because only a few bits of authentication data are embedded. Experimental results show that the proposed fragile watermarking scheme can be applied to the integrity authentication systems based on biometric image.

<p>Video Encryption is widely used in many real-time applications today. Despite numerous video encryption techniques that are available today, the challenges such as time and space complexity, real time latency, scalability and vulnerability towards few attacks still exist in the research domain, however few algorithms have achieved acceptable computational complexity, but in such cases vulnerability to certain attacks (differential, statistical, plain text attack, and cipher text attacks) are still a threat to secure video transmission. To the best of our knowledge, a comprehensive but detailed systematic literature review on video encryption is needed for the researchers in the scientific community. This paper, therefore, presents a systematic literature review of 30 scientific documents extracted from platforms like scopus and web of science. The paper, comprehensively addresses, various techniques of video encryption and encoding, different evaluation parameters to testify the performance of the algorithms and discusses the challenges of the existing video encryption algorithms. After careful investigation, it has been observed the approaches which involve encryption of the video data post the same has been encoded is the most efficient and scalable approach towards video encryption. In addition, it also implies that in near future, the proposed algorithms, must be evaluated based on the various categorization of parameters illustrated in this paper.</p>

In the literature, robust reversible watermarking schemes (RWSs) allow the extraction of watermarks after the images have suffered attacks; however, the modified images are compromised. On the other hand, self-recovery schemes will restore the compromised regions of the images, but no secret messages are inserted in these schemes. A framework for robust reversible watermarking with signal restoration capabilities was previously proposed in the literature. This study selects four fragile reversible watermarking techniques and two self-recovery schemes to design different framework configurations. These configurations are evaluated to test the framework’s performance and determine the structure that yields better results in terms of perceptual transparency using a well-known image database as the signal input. It was found that fragile reversible watermarking schemes hold low perceptual distortion, while self-recovery schemes produce high perceptual distortion levels. The inherent characteristics of each algorithm determine, a priori, the behavior of the framework, which is approximated by a proposed equation.

This paper proposes an authentication scheme for JPEG images based on digital signature and semi-fragile watermarking. It can detect and locate malicious manipulations made to the image, and verify the ownership of the image at the same time. The algorithm uses the invariance of the order relationship between two DCT coefficients before and after JPEG compression to embed image content dependent watermark, therefore the watermark can survive the JPEG lossy compression. Since the scheme is based on the security of the cryptographic hash function and public key algorithm, it is believed to be secure to the extent that cryptography is believed to be. Theoretical analysis and experimental results show that the proposed scheme has the desired property and good performance for image authentication.

Fragile watermarking using finite field trigonometrical transforms

Steganography is a technique of writing hidden messages, whereas a fragile watermarking scheme is used for image authentication and integrity verification. In this study, we developed a method for block-based tamper detection steganography that can verify not only forgery but also a cutting attack on a stego image. Moreover, a stego image has better quality and more capacity than some previous steganography works. For verifying the integrity of the secret information, both the previous block and the most significant bits (MSBs) of the current block were used. The number of insertion bits per pixel is determined according to the variance of adjacent pixels. Secret information embedding and extraction are performed by using a block unit in the spatial domain of an image.

We present a domain-independent ICA-based approach to watermarking. This approach can be used on images, music or video to embed either a robust or fragile watermark.In the case of robust watermarking, the method shows high information rate and robustness against malicious and non-malicious attacks, while keeping a low induced distortion. The fragile watermarking scheme, on the other hand, shows high sensitivity to tampering attempts while keeping the requirement for high information rate and low distortion. The improved performance is achieved by employing a set of statistically independent sources (the independent components) as the feature space and principled statistical decoding methods. The performance of the suggested method is compared to other state of the art approaches. The paper focuses on applying the method to digitized images although the same approach can be used for other media, such as music or video.

In this paper, a fragile watermarking scheme is proposed for Tamper Detection in images. Here, watermark is derived from the original host image, which is consists of reference-bits and check-bits and is embedded into the host image using a lossless data-hiding technique. On the receiver side, one can attempt to extract the watermark bits and recover the original image. By comparing the watermark data extracted from received image and calculated from recovered image, tamper blocks can be identified.