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Nowadays, multimedia applications are extensively utilized and communicated over Internet. Due to the use of public networks for communication, the multimedia data are prone to various security attacks. In the past few decades, image watermarking has been extensively utilized to handle this issue. Its main objective is to embed a watermark into a host multimedia data without affecting its presentation. However, the existing methods are not so effective against multiplicative attacks. Therefore, in this paper, a novel quantum-based image watermarking technique is proposed. It initially computes the dual-tree complex wavelet transform coefficients of an input cover image. The watermark image is then scrambled using Arnold transform. Thereafter, in the lower coefficient input the watermark image is embedded using quantum-based singular value decomposition (SVD). Finally, the covered image is obtained by applying the inverse dual-tree complex wavelet transform on the obtained coefficients. Comparative analyses are carried out by considering the proposed and the existing watermarking techniques. It has been found that the proposed technique outperforms existing watermarking techniques in terms of various performance metrics.

In a buyer–seller watermarking protocol, a seller should embed a buyer's fingerprinting and seller's watermark into the work before the sale of a work to a buyer. If the work is violated, the fingerprinting and watermark can be extracted to correctly identify who holds the legal copyright of the work and trace the illegal reseller. In this paper, we propose a robust buyer–seller watermarking scheme based on discrete wavelet transformation (DWT) which embeds the buyer's fingerprinting and seller's watermark into an image. Besides, during the extraction phase, the extraction of the fingerprinting and watermark does not require the original image for more feasibility in real application. The proposed scheme has the following advantages. Firstly, the extraction of the fingerprinting and watermark does not require the original image. Secondly, the watermarked image maintains a good visual quality after the fingerprinting and watermark embedding. Thirdly, the proposed scheme is robust against several image processing attacks.

An improved scheme for integrity protection of binary images representing text documents based on the topologies of these images is proposed. The image skeleton and the inverse skeleton are found through thinning and the skeleton signature is combined with watermark information. The result is encrypted asymmetrically and hidden in embeddable locations of the image. A series of attack experiments are conducted to demonstrate that the approach is capable of detecting tampering. Even single malicious pixel modifications are detected. The approach has a lower computation cost than previous methods.

In this paper, a novel watermarking technique based on parametric slant-Hadamard transform is presented. Our approach embeds a pseudo-random sequence of real numbers in a selected set of the parametric slant-Hadamard transform coefficients. By exploiting statistical properties of the embedded sequence, the mark can be reliably extracted without resorting to the original uncorrupted image. The presented method is capable of increasing the flexibility of the watermarking scheme, where the changes in parameter set help to improve fidelity and robustness against a number of attacks. Experimental results show that the proposed technique is secure and indeed highly robust to these attacks.

In this paper, a novel image watermarking scheme based on a self-reference technique is proposed. The meaningful watermark is embedded into a gray-level image according to the relation between the constructed reference image and the original host. In order to be robust against Jpeg compression, the reference image should be robust under Jpeg compression. Firstly, the original image is transformed into DCT domain; and then most of the high frequency coefficients are omitted; after the quantization step and inverse DCT transform, we can obtain a robust reference. By considering the relation between the original image and its reference, we can embed the watermark into the host. The watermark extraction process is oblivious. Experimental results under several attacks show good robustness of the proposed scheme. Especially under cropping and Jpeg compression attacks, the watermark can be extracted with only few errors.

In this paper, an adaptive digital image watermarking technique using fuzzy gradient on DCT domain is presented. In our approach, the image is divided into separate blocks and the DCT is applied on each block individually. Then, the watermark is inserted in the transform domain and the inverse transform is carried out. We increase the robustness of the watermark by increasing the watermark strength. However, this reduces the fidelity of the watermarking scheme. This is because the fidelity and robustness of watermarking are generally in conflict with each other. To improve the fidelity, a new fuzzy-based method is introduced. In this method, a fuzzy gradient-based mask is generated from the host image. Then, as a post-processing stage, the generated mask is combined with the watermarked image. Experimental results show that the proposed technique has high fidelity as well as high robustness against a variety of attacks.

Objective: This research aims to survey the efforts of researchers in response to the new and disruptive technology of skin cancer apps, map the research landscape from the literature onto coherent taxonomy, and determine the basic characteristics of this emerging field. In addition, this research looks at the motivation behind using Smartphone apps in the diagnosis of skin cancer and in health care and the open challenges that impede the utility of this technology. This study offers valuable recommendations to improve the acceptance and use of medical apps in the literature. Methods: We conducted a comprehensive survey using the keywords “skin cancer,” “apps,” and “Smartphone” or “m-Health” in different variations to find all the relevant articles in three major databases: Web of Science, Science Direct, and IEEE Xplore. These databases broadly cover medical and technical literature. Results: We found 110 articles after a comprehensive survey of the literature. Out of the 110 articles, 46 present actual attempts to develop and design medical apps or share certain experiences of doing so. Twenty-eight articles consist of analytical studies on the incidence of skin cancer, the classification of malignant cancer or benign cancer, and the methods of prevention and diagnosis. Twenty-two articles comprise studies that range from the evaluative or comparative study of apps to the exploration of the desired features for skin cancer detection. Fourteen articles consist of reviews and surveys that refer to actual apps or the literature to describe medical apps for a specific specialty, disease, or skin cancer and provide a general overview of the technology. New research direction: With the exception of the 110 papers reviewed earlier in results section, the new directions of this research were described. In state-of-the-art, no particular study presenting watermarking and stenography approaches for any type of skin cancer images based on Smartphone apps is available. Discussion: Researchers have attempted to develop and improve skin cancer apps in several ways since 2011. However, several areas or aspects require further attention. All the articles, regardless of their research focus, attempt to address the challenges that impede the full utility of skin cancer apps and offer recommendations to mitigate their drawbacks. Conclusions: Research on skin cancer apps is active and efficient. This study contributes to this area of research by providing a detailed review of the available options and problems to allow other researchers and participants to further develop skin cancer apps, and the new directions of this research were described.

The watermarking technique is an active subject in current research used as a solution for copyright protection in multimedia documents. In this paper, we propose the first hardware invisible robust video watermarking application based on motion estimation. Since the designers of this application face many challenges, two types of architecture are performed: static and dynamic/partial reconfigurable architecture. The proposed architecture is adapted to HEVC encoded video. Two protection techniques are linked up: the digital watermarking to insert a watermark in the video, and the scrambling technique for overall video protection. The watermark embedding is treated in the horizontal and vertical components of even motion vectors. Eventually, the entire vectors are scrambled. The used watermark is a binary sequence where only one bit is inserted into the horizontal and the vertical components of motion vectors. The recommended architecture applies for slow and fast video sequence, where we use a motion estimator reconfigured according to the macro-block video movement. We also utilize a pipeline structure and a clock gating module to increase computing power and reduce power consumption. Experimental results show that the suggested static and dynamic/partial reconfigurable architecture guarantees material efficiency and superior performance in terms of frequency and power consumption.

Watermarking techniques for vector graphics dislocate vertices in order to embed imperceptible, yet detectable, statistical features into the input data. The embedding process may result in a change of the topology of the input data, e.g., by introducing self-intersections, which is undesirable or even disastrous for many applications. In this paper we present a watermarking framework for two-dimensional vector graphics that employs conventional watermarking techniques but still provides the guarantee that the topology of the input data is preserved. The geometric part of this framework computes so-called maximum perturbation regions (MPR) of vertices. We propose two efficient algorithms to compute MPRs based on Voronoi diagrams and constrained triangulations. Furthermore, we present two algorithms to conditionally correct the watermarked data in order to increase the watermark embedding capacity and still guarantee topological correctness. While we focus on the watermarking of input formed by straight-line segments, one of our approaches can also be extended to circular arcs. We conclude the paper by demonstrating and analyzing the applicability of our framework in conjunction with two well-known watermarking techniques.

The interest for multimedia contents authentication has recently increased. In particular watermarking-based authentication schemes seem to be offering some advantages with respect to classical cryptography tools (e.g. real content authentication, localization of manipulations, storage format independence, transparency to common signal processing, etc.). In this paper a simple and secure self recovery authentication algorithm which hides an image digest into some DWT subbands of the to be authenticated image is presented. This technique has been designed for video surveillance and/or remote sensing applications. The main goal of this approach is to detect possible malevolent object manipulations undergone by the image (object replacing and/or deletion) by means of a self recovery processing. This valuable characteristic has to be maintained also when an image is processed through an usual and friendly transformation like JPEG compression. Particular care is given to make the scheme robust against innocuous manipulations, and secure against forgery attempts. Experimental results are presented that demonstrate the good performance of the proposed system.

In this paper, we investigate the general problem of data hiding and propose an approach for effective cover noise interference rejection in oblivious applications. We first evaluate the performance in the commonly used direct sequence modulation approach where a low-power signal is embedded into the original cover signal. The optimal detection is derived and its performance is analyzed. Second, we study a novel approach in oblivious data hiding and evaluate its performance and compare it with existing algorithms. Both simulation studies and empirical data hiding results validate its efficiency in the multimedia oblivious applications.

Many current watermarking algorithms insert data in the spatial or transform domains like the discrete cosine, the discrete Fourier, and the discrete wavelet transforms. In this paper, we present a data-hiding algorithm that exploits the singular value decomposition (SVD) representation of the data. We compute the SVD of the host image and the watermark and embed the watermark in the singular vectors of the host image. The proposed method leads to an imperceptible scheme for digital images, both in grey scale and color and is quite robust against attacks like noise and JPEG compression.

In the current digital age, the piracy of digital media content has become rampant. Illegal distribution of movies and video clips on a global scale causes a significant loss to the media industry. To prevent such theft and distribution of content, we use a watermarking technique for videos where copyright information is hidden inside the original video in the form of a watermark video. Using a video as the watermark facilitates the user in hiding a large amount of information. The watermarking scheme used in this paper is semi-fragile, such that tampering of videos can be detected with relative ease. To improve the robustness of the watermark, we embed the watermark in frequency domain, where we use DWT+DCT+SVD to embed the watermark. The original video and watermark video are transformed by using the DWT and DCT sequentially, then the singular values of the watermark with some embedding strength are added to the singular values of the original video thus obtaining a watermarked video. Some detection tools which are available today cannot detect the watermark video inside the original video. This method equalizes the frames of the watermark and original video to reduce time consumed as well as complexity. The effects of various attacks on the watermarked video have been analyzed using the calculated PSNR values.

To achieve robustness and imperceptibility, an adaptive compressed domain blind video watermarking method based on Discrete Wavelet Transform (DWT) is proposed in this research. In this technique, multiple binary images derived from a single watermark image are first embedded in a video sequence. The spatial spread spectrum watermark is directly incorporated in the compressed bit streams by modifying the four sets of discrete wavelet coefficients. Comprehensive simulation experiments demonstrate that the developed approach is efficient and also robust against spatial attacks such as scaling and frame averaging, noise attacks such as Gaussian and salt pepper noise, and temporal attacks like frame dropping and shifting. Moreover, the proposed approach can also withstand against rotation attacks of arbitrary angle.

This paper proposes a multimodal biometric based authentication (verification and identification) with secured templates. Multimodal biometric systems provide improved authentication rate over unimodal systems at the cost of increased concern for memory requirement and template security. The proposed framework performs person authentication using face and fingerprint. Biometric templates are protected by hiding fingerprint into face at secret locations, through blind and key-based watermarking. Face features are extracted from approximation sub-band of Discrete Wavelet Transform, which reduces the overall working plane. The proposed method also shows high robustness of biometric templates against common channel attacks. Verification and identification performances are evaluated using two chimeric and one real multimodal dataset. The same systems, working with compressed templates provides considerable reduction in overall memory requirement with negligible loss of authentication accuracies. Thus, the proposed framework offers positive balance between authentication performance, template robustness and memory resource utilization.

In this paper, a dynamic stochastic resonance (DSR) based watermark detection technique in discrete wavelet transform (DWT) domain is presented. Pseudo random bit sequence having certain seed value is considered as a watermark. Watermark embedding is done by embedding random bits in spread-spectrum fashion to the significant DWT coefficients. Watermark detection is quantitatively characterized by the value of correlation. The performance of watermark detection is improved by DSR which is an iterative process that utilizes the internal noise present in the image or external noise which is added during attacks. Even under various noise attacks, geometrical distortions, image enhancement and compression attacks, the DSR-based random bits detection is observed to give noteworthy improvement over existing watermark detection techniques. DSR-based technique is also found to give better detection performance when compared with the suprathreshold stochastic resonance-based detection technique.

In this paper, a selective curvelet coefficient digital watermarking algorithm is proposed. Traditionally, curvelet watermarks are embedded into all sample frequency bands. However, the study of individual band behavior and the use of single band for watermarking have not been reported. The selective band will provide an addition security feature against any physical tampering. This paper aims to give an intensive study on the robustness of watermarking using selective curvelet coefficients from a single band and to find out the best band for embedding watermark. Wrapping of specially selected Fourier samples is employed to implement Fast Discrete Curvelet Transforms (FDCT) to transform the digital image to the curvelet domain.

Watermarking is a potential method for the protection of ownership rights on digital images. A robust, invisible, non-blind watermarking scheme in the wavelet domain is proposed in this paper. The watermark is embedded in the mid frequency band after performing a single level wavelet decomposition using Discrete Wavelet Transform (DWT). The coefficients are grouped randomly prior to watermarking. The watermarked image is tested for various attacks including filtering and geometric attacks. The novelty of the proposed approach is that it provides better resistance to collusion attack also when compared with existing spatial domain approach. The appropriate mid frequency band for embedding the watermark is tested and the HL band proves to be the best.

In this paper, six robust non-blind watermarking schemes based on curvelet transform are proposed. Single band watermarking method was proposed in Ref. 1. This paper develops the single band watermarking method and adds Human Vision System (HVS) to form six different multi-bands watermarking methods. With the increasing redundancy of watermark, the robustness of the algorithm will be investigated and comparative studies with the single band watermarking will be shown. The experimental results demonstrate that the proposed algorithms have great robustness against various imaging attacks.

Digital watermarking is a process of embedding hidden information called watermark into different kinds of media objects. It uses basic modulation, multiplexing and transform techniques of communication for hiding information. Traditional techniques used are least significant bit (LSB) modification, discrete cosine transform (DCT), discrete wavelet transform (DWT), discrete Fourier transform (DFT), code division multiple access (CDMA) or a combination of these. Among these, CDMA is the most robust against different attacks except geometric attacks. This paper proposes a blind and highly robust watermarking technique by utilizing the basis of orthogonal frequency division multiplexing (OFDM) and CDMA communication system. In this scheme, the insertion process starts by taking DFT of host images, permuting the watermark bits in randomized manner and recording them in a seed as a key. Then PSK modulation follows inverse DFT (IDFT) that gives watermark information as OFDM symbols. These symbols are spread using spreading codes and then arithmetically added to the host image. Finally, scheme applies inverse DCT (IDCT) to get watermarked host images. The simulation results of the proposed scheme are compared with CDMA-based scheme in DCT domain. The results show that the robustness of the proposed scheme is higher than the existing scheme for non-geometric attacks.