Fragile watermarking using finite field trigonometrical transforms

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

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.

A gray-level intensity image can be employed as a host image for hiding a watermark image to protect information security. Past research works demonstrate that a gray-level hidden image can be embedded into the host image by a digital phase-only holography method. However, the fidelity of retrieved watermark image from the host image is not very satisfactory and the host image quality is degraded due to the insertion of external data bits, especially when observers focus on the saliency regions in the host image. To address this problem, we propose a steganography method based on digital holography and the saliency map of the host image. First, we calculate the hidden capacity (number of bits to be replaced) for each host image pixel based on the weighted sum of pixel intensity and saliency value. Next, a multilevel phase-only digital hologram of the watermark image will be calculated by the Gerchberg–Saxton method under the constraint of the hidden capacity of host image. Finally, we embedded the multilevel phase-only digital hologram into the host image by replacing a corresponding number of bits in each pixel. In this way, the host image can preserve good image fidelity for its saliency regions even if we hide a large amount of digital hologram data into the host image. The experimental results show that the quality of retrieved watermark image from the host image and the quality of saliency regions in the watermarked host image, in our proposed scheme, are superior to the state-of-the-art works reported.

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.

Due to the rise in many industrial environment applications involving distributed networked collaborative intelligent measurement systems, intelligent monitoring and multi-sensor information exchange of private information, digital image information security and hidden image authentication, tampering detection, correction, and automatic intelligent self-recovery have become critical concerns. Towards that end, there is a need for more secure, efficient, and robust-to-unauthorized-tampering digital image watermarking, information hiding and authentication schemes. In our prior work, we introduced non-blind watermarking schemes where the carrier and watermark images are available at the receiver's end. We also proposed a double-blind scheme where both the carrier and the watermark images are not available at the receiver's end, but at the expense of possible lower pixel tampering, authentication and automatic intelligent self-correction ability. This paper proposes a blind wavelet-based, high capacity, secure digital watermarking and information hiding scheme with higher tampering localization and authentication that nullifies the need to have the carrier image available at the receiving end. The proposed scheme also increases robustness to image authentication and automatic self-recovery and correction compared to our prior double-blind scheme. The scheme is high capacity and sustains hiding secret hidden and watermarking images of the same full size as an arbitrary-sized carrier image. One of the benefits of the blind watermarking scheme is that it allows usage of varying and arbitrary carrier images that are unknown and unavailable anywhere, including the receiver's end. This is to prevent hackers' recognition of a familiar carrier image and their potential unauthorized tampering. Here, in this paper, two grayscale images are inserted in a colored carrier image. Here the watermark image is used for authentication and tamper localization. The second image is used as ownership or encoded secret hidden message image. The Arnolds Transform is used to introduce added security to a hidden image. The proposed scheme uses an embedded correction matrices mechanism for the extracted hidden information self-recovery from various tampering and digital attacks by unauthorized hackers.

The ease and extensive use of digital imaging systems raise serious questions about integrity and authenticity of digital images particularly in medical applications. A medical image requires great integrity of content since any change in the image might affect the diagnosis even if it is of small amount. Fragile watermark could be the best technique to provide efficient image authentication tool for medical images, in this paper we present different methods developed in image watermarking used in order to verify integrity and authenticity of images. We will present after that our proposed method and validated the embedding and extracting procedures

In this article is presented an application of synthetic hologram as fragile watermarking. The proposed technique is a frequency domain watermarking, based on computer generated hologram. Our technique, named Fragile Synthetic Holographic Watermarking (F-SHW), is suitable for ID Cart image authentication. In this paper, the F-SHW is applied to Color Images as well as to Gray Scale ones. The proposed schema is based on the knowledge of original mark from the Authentication Entity, for applying Image Correlation between this and the extracted one. Due to the application the mark is encrypted using a private key (symmetric schema).

Capability of accurately locating tampered pixels is desirable in image authentication. We propose a novel statistical scheme of fragile watermarking, in which a set of tailor-made authentication data for each pixel together with some additional test data are embedded into the host image. On the authentication side, examining the pixels and their corresponding authentication data will reveal the exact pattern of the content modification. As long as the tampered area is not too extensive, two distinct probability distributions corresponding to tampered and original pixels can be used to exactly identify the tampered pixels.

The main objectives of digital image watermarking schemes are to provide acceptable level of both imperceptibility and robustness for wide variety of host and watermark images. To support watermarking scheme in accomplishing these objectives, suitable watermark strength is identified in the form of scaling factor using Dynamic-PSO (DPSO) for colored images. A non-blind, DWT-SVD-based watermarking scheme is used to embed watermark in host image. Results achieved through DPSO are compared with PSO and other widely accepted variants of PSO. Experiment results demonstrate that performance of underline watermarking scheme when used with DPSO is better than other variants of PSO.

Image watermarking plays a vital role in providing protection from copyright violation. However, conventional watermarking techniques typically exhibit trade-offs in terms of image quality, robustness and capacity constrains. More often than not, these techniques optimize on one constrain while settling with the two other constraints. Therefore, in this paper, an enhanced saliency detection based watermarking method is proposed to simultaneously improve quality, capacity, and robustness. First, the enhanced structured matrix decomposition (E-SMD) is proposed to extract salient regions in the host image for producing a saliency mask. This mask is then applied to partition the foreground and background of the host and watermark images. Subsequently, the watermark (with the same dimension of host image) is shuffled using multiple Arnold and Logistic chaotic maps, and the resulting shuffled-watermark is embedded into the wavelet domain of the host image. Furthermore, a filtering operation is put forward to estimate the original host image so that the proposed watermarking method can also operate in blind mode. In the best case scenario, we could embed a 24-bit image as the watermark into another 24-bit image while maintaining an average SSIM of 0.9999 and achieving high robustness against commonly applied watermark attacks. Furthermore, as per our best knowledge, with high payload embedding, the significant improvement in these features (in terms of saliency, PSNR, SSIM, and NC) has not been achieved by the state-of-the-art methods. Thus, the outcomes of this research realizes a trade-off independent image watermarking method, which is a first of its kind in this domain.

Presented is an efficient watermarking scheme using Particle Swarm Optimization (PSO) to watermark host fingerprint images with their corresponding facial images in the Discrete Cosine Transform (DCT) domain. PSO is used to find the best DCT coefficients’ locations in the host image where the facial image data can be embedded, so that the distortion produced in the host image is minimum. The objective function for PSO is formulated in terms of the Structural Similarity Index (SSIM) and the Orientation Certainty Level Index (OCL) so as to base it on the simple visual effect of the human visual perception capability and correct minutia prediction ability. The results exhibit better watermarked image quality while retaining the feature set of the original fingerprint. Moreover, the proposed technique is robust so that the extraction of watermark is possible even after the watermarked image is exposed to attacks. As a result, at the receiver’s end, the watermarked fingerprint image and the extracted facial image can be verified for a secure and accurate biometric based personal authentication.

Digital watermarking provides the solution for problems such as copyright and authentication in today’s digital world of communication. Trustworthy watermarking techniques should provide the protection for rightful ownership, robustness and resist against attacks such as filtering and modification. In this paper, we proposed an efficient watermarking scheme based on singular value decomposition (SVD) and quantum Hilbert image scrambling. In the proposed watermarking scheme, first watermark is scrambled using quantum Hilbert image scrambling then perform alpha blending on scrambled watermark and SVD transformed cover image followed by alpha mixing operation. Finally, perform SVD operation of the generated signal; after alpha blending operation, we get watermarked image. The experimental results show strength of the proposed technique in terms of the robustness and security. Performance of the proposed scheme is tested on different image quality parameters of watermarked and host image. These are peak signal-to-noise ratio (PSNR), mean square error (MSE) and normalized cross-correlation (NCC), average difference (AD), maximum difference (MD), and structural contents (SC).KeywordsSingular value decompositionWatermarkQuantum Hilbert image scramblingSteganography

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.

Binocular visual characteristics based fragile watermarking scheme for tamper detection in stereoscopic images

Nowadays, digital watermarking approaches are proposed for content authentication of digital images. Digital watermarking is a technique that is used to embed watermarks into a digital image. In this work, a novel double authentication mechanism is proposed to ensure the authenticity of image content based on the hash function and signature value. The suggested technique is capable of finding malicious image manipulation even if simple image processing operations have unintentionally corrupted them. Using the hash function, the difficulty level of finding embedded bits is increased and this scheme also withstands any kind of attacks. Moreover, the proposed technique is simple which is based on modifying a single pixel value in the host image itself using the surrounding pixels i.e., neighboring pixels. Experimental results are shown to illustrate the system’s capability to detect unauthorized image alteration.