Geometric Attacks Research Articles

Performance analysis of image steganography using wavelet transform for safe and secured transaction

Internet applications are increased and growing at efficient way. By this technological growth, data communication in the internet in secured way has got a challenging task. Transmitting information in network is a great risk. Hacking the data and use those data for their benefits is done by intruders. To control these unwanted acts, steganography is used. It ensures safety of secret message. Invisible communication is a study by Steganography and it denotes with communicating message hiding. Data embedding can make in transform and spatial domain for secret communication, military communication, multimedia (hiding, copyright protection), authentication etc. A best steganography algorithm will have maximum embedding capacity, high fidelity and the good security level. Image Steganography has the robustness and security problem in the existing work. For the defence application, social problems such as terrorists, more number of attacks (cyber) and Geometric attack are caused. To overcome such drawbacks, this research work proposes Discrete Wavelet Transform (DWT) which has more advantages than other transforms technique like DCT (Discrete Cosine Transform). This is because of quality scalability, Interest in region coding, low bit rate transmission which is quickly operating and also it is compatible to Visual System by Human that provides good perception quality. Geometric attack induces synchronization errors between the first image and also the extracted stego image throughout the detection method during which its positions are modified. Image characters are analyzed well by Wavelet Space - frequency property of localization which makes additional strong to the attack such as geometric. This property will enlarge the embedded area and improves the security. Hence DWT results in high imperceptibility and PSNR in range of 30-54 dB.

Digital hologram watermarking by embedding Fresnel-diffracted watermark data

Since holograms are very costly content, security against holograms is very important. Hologram watermarking has been researched for a long time as a security solution for the digital hologram distributed on the network as the hologram is digitized. We deal with a digital watermarking for digital hologram contents as ownership protection tool. Since holograms have different optical characteristics from natural images, a watermarking technique using these characteristics should be needed. We therefore selected Fresnel diffraction for this property. Both of the host holograms and the watermarks are diffracted more than once for each. The results are refracted to concentrate the diffracted data into the localized regions of the transformed plane so that the region occupied one region among them. From this process, we change and select the region of the watermark. We experimented our scheme with various test images for various attacks on data-manipulating attack and geometric attack. It is apparently recognizable for eye inspection. From the results, we expect the proposed watermarking scheme to be an appropriate solution for protecting the ownership of holograms.

A Robust Multi-Watermarking Algorithm for Medical Images Based on DTCWT-DCT and Henon Map

To resolve the contradiction between existing watermarking methods—which are not compatible with the watermark’s ability to resist geometric attacks—and robustness, a robust multi-watermarking algorithm suitable for medical images is proposed. First, the visual feature vector of the medical image was obtained by dual-tree complex wavelet transform and discrete cosine transform (DTCWT-DCT) to perform multi-watermark embedding and extraction. Then, the multi-watermark was preprocessed using the henon map chaotic encryption technology to strengthen the security of watermark information, and combined with the concept of zero watermark to make the watermark able to resist both conventional and geometric attacks. Experimental results show that the proposed algorithm can effectively extract watermark information; it implements zero watermarking and blind extraction. Compared with existing watermark technology, it has good performance in terms of its robustness and resistance to geometric attacks and conventional attacks, especially in geometric attacks.

Dual Zero-Watermarking Scheme for Two-Dimensional Vector Map Based on Delaunay Triangle Mesh and Singular Value Decomposition

Digital watermarking is important for the copyright protection of electronic data, but embedding watermarks into vector maps could easily lead to changes in map precision. Zero-watermarking, a method that does not embed watermarks into maps, could avoid altering vector maps but often lack of robustness. This study proposes a dual zero-watermarking scheme that improves watermark robustness for two-dimensional (2D) vector maps. The proposed scheme first extracts the feature vertices and non-feature vertices of the vector map with the Douglas-Peucker algorithm and subsequently constructs the Delaunay Triangulation Mesh (DTM) to form a topological feature sequence of feature vertices as well as the Singular Value Decomposition (SVD) matrix to form intrinsic feature sequence of non-feature vertices. Next, zero-watermarks are obtained by executing exclusive disjunction (XOR) with the encrypted watermark image under the Arnold scramble algorithm. The experimental results show that the scheme that synthesizes both the feature and non-feature information improves the watermark capacity. Making use of complementary information between feature and non-feature vertices considerably improves the overall robustness of the watermarking scheme. The proposed dual zero-watermarking scheme combines the advantages of individual watermarking schemes and is robust against such attacks as geometric attacks, vertex attacks and object attacks.

Rotation and scale invariant image watermarking based on polar harmonic transforms

Geometric attacks such as rotation and scale can destroy the synchronization of watermarking, designing a geometric-distortion resilient watermarking is currently a challenging work. In this paper, we propose a robust image watermarking technique based on polar harmonic transforms (PHTs) which are defined in a circle domain. The watermarking embedding process includes three principal steps: Firstly, we explicitly exploit invariant properties of PHTs’ moments to compute orthogonal moment features. Next, according to the order and repetition of PHTs’ moments, steady moments those are not sensitive to geometric attacks are picked out. Finally, watermark embedding is performed through quantization modulation on the selected steady moments, and the watermarked image is reconstructed by combining the original and the compensating image acquired from unmodulated and modulated PHTs’ moments, respectively. Experimental results show that the proposed watermarking approach is robust to both geometric distortions (rotation and scaling) and general signal processing attacks (Gaussian filtering, median filtering, average filtering, Gaussian noise, salt & pepper noise, speckle noise, JPEG compression, etc.) and outperforms state-of-the-art watermarking methods.

Blind Image Watermarking Based on Adaptive Data Spreading in n-Level DWT Subbands

This paper proposes a new adaptive watermarking scheme for digital images, which has the properties of blind extraction, invisibility, and robustness against attacks. The typical scheme for invisibility and robustness consisted of two main techniques: finding local positions to be watermarked and mixing or embedding the watermark into the pixels of the locations. In finding the location, however, our scheme uses a global space such that the multiple watermarking data is spread out over all four lowest-frequency subbands, resulting from n-level Mallat-tree 2D (dimensional) DWT, where n depends on the amount of watermarking data and the resolution of the host image, without any further process to find the watermarking locations. To embed the watermark data into the subband coefficients, weighting factors are used according to the type and energy of each subband to adjust the strength of the watermark, so we call this an adaptive scheme. To examine the ability of the proposed scheme, images with various resolutions are tested for various attacks, both pixel-value changing attacks and geometric attacks. With experimental results and comparison to the existing works we show that the proposed scheme has better performance than the previous works, except those which specialize in certain types of attacks.

Shape Adaptable Medical Multimedia Processing

Introduction:Electronic medical healthcare systems are becoming the backbone of health organizations over the world. The huge amounts of medical multimedia produced by these systems especially images and videos are transmitted by the computer networks that connect these systems. The variability in the shape and texture of transferred medical multimedia data needs adaptable procedures to process these data efficiently. In other words, these procedures must adjust automatically based on the shape of region of interests in the medical multimedia images to cope with fast changes in the healthcare environments. In this paper, we have proposed shape adaptable watermarking approaches for medical multimedia processing systems. The medical images generated by X-rays, MRI and CT modalities are used in our experiments to test proposed approaches. In addition, these approaches were tested under different kinds of signal processing and geometric attacks. The comparative comparison of our proposed approaches with state-of-art approaches proved the superiority and capability of our approaches to adjust the number of selected subands of medical cover image to embed and extract the hospital watermark logos.Background and Objective:The development of an adjustable approach to process medical multimedia signals for healthcare system. The aim of this research is to select adaptably the number of subands of cover image to hide the information of hospital logo watermark inside them such that embedded watermarks can resist different kinds of attacks.Method:The proposed adjustable approach consists of suband selection method, criterion, embedding and extraction procedures, DWT transform, attacks, evaluation metrics,etc.Results & Conclusion:It provides robust and adjustable method to embed and extract watermark logo at different resolution levels of cover medical image and uses with images of different sizes and modalities.

Robust watermarking in curvelet domain for preserving cleanness of high-quality images

Watermarking inserts invisible data into content to protect copyright. The embedded information provides proof of authorship and facilitates the tracking of illegal distribution, etc. Current robust watermarking techniques have been proposed to preserve inserted copyright information from various attacks, such as content modification and watermark removal attacks. However, since the watermark is inserted in the form of noise, there is an inevitable effect of reducing content visual quality. In general, most robust watermarking techniques tend to have a greater effect on quality, and content creators and users are often reluctant to insert watermarks. Thus, there is a demand for a watermark that maintains maximum image quality, even if the watermark performance is slightly inferior. Therefore, we propose a watermarking technique that maximizes invisibility while maintaining sufficient robustness and data capacity to be applied in real situations. The proposed method minimizes watermarking energy by adopting curvelet domain multi-directional decomposition to maximize invisibility and maximizes robustness against signal processing attacks with a watermarking pattern suitable for curvelet transformation. The method is also robust against geometric attacks by employing the watermark detection method utilizing curvelet characteristics. The proposed method showed very good results of a 57.65 dB peak signal-to-noise ratio in fidelity tests, and the mean opinion score showed that images treated with the proposed method were hardly distinguishable from the originals. The proposed technique also showed good robustness against signal processing and geometric attacks compared with existing techniques.

A Novel Robust Watermarking Algorithm for Encrypted Medical Image Based on DTCWT-DCT and Chaotic Map

In order to solve the problem of patient information security protection in medical images, whilst also taking into consideration the unchangeable particularity of medical images to the lesion area and the need for medical images themselves to be protected, a novel robust watermarking algorithm for encrypted medical images based on dual-tree complex wavelet transform and discrete cosine transform (DTCWT-DCT) and chaotic map is proposed in this paper. First, DTCWT-DCT transformation was performed on medical images, and dot product was per-formed in relation to the transformation matrix and logistic map. Inverse transformation was undertaken to obtain encrypted medical images. Then, in the low-frequency part of the DTCWT-DCT transformation coefficient of the encrypted medical image, a set of 32 bits visual feature vectors that can effectively resist geometric attacks are found to be the feature vector of the encrypted medical image by using perceptual hashing. After that, different logistic initial values and growth parameters were set to encrypt the watermark, and zero-watermark technology was used to embed and extract the encrypted medical images by combining cryptography and third-party concepts. The proposed watermarking algorithm does not change the region of interest of medical images thus it does not affect the judgment of doctors. Additionally, the security of the algorithm is enhanced by using chaotic mapping, which is sensitive to the initial value in order to encrypt the medical image and the watermark. The simulation results show that the pro-posed algorithm has good homomorphism, which can not only protect the original medical image and the watermark information, but can also embed and extract the watermark directly in the encrypted image, eliminating the potential risk of decrypting the embedded watermark and extracting watermark. Compared with the recent related research, the proposed algorithm solves the contradiction between robustness and invisibility of the watermarking algorithm for encrypted medical images, and it has good results against both conventional attacks and geometric attacks. Under geometric attacks in particular, the proposed algorithm performs much better than existing algorithms.

Dual Video Watermarking Algorithm Based on SIFT and HVS in the Contourlet Domain

We propose dual un-compressed video watermarking algorithms based on human visual system and scale invariant feature transform (SIFT) in the contourlet domain. First, every frame is decomposed by contourlet transform to obtain the low-frequency band and several high-frequency sub-bands in different directions. The energy value of every high-frequency sub-band is calculated. The low-frequency sub-band and the high-frequency sub-bands of the largest energy values are chosen to be embedded into watermarking signals. Second, the first watermarking algorithm is realized to embed watermarking signals by adjusting the size ratio between the coefficient histograms of low-frequency sub-band because the coefficient histogram of low-frequency sub-band possesses invariance to conventional geometric transform. Third, to the second watermarking algorithm, the human visual masking threshold based on contourlet domain is calculated as the maximum embedding tolerance, which is embedded in the largest energy value of the high-frequency sub-band as watermarking signals to guarantee the imperceptibility. Finally, when the watermarked video frame suffered from geometrically attacks, the SIFT and fine corrections are combined to effectively correct and restore the synchronization between geometrically attacked video frames and watermarking signals. The experimental results indicate that: 1) the visual masking based on video motion information in the contourlet domain can effectively improve the transparency and 2) combining the histogram mapping in low-frequency sub-band coefficients with SIFT and fine corrections can resist common geometric attacks and therefore improve the robustness of the watermarking algorithm.

Geometrically Invariant Color Medical Image Null-Watermarking Based on Precise Quaternion Polar Harmonic Fourier Moments

The traditional embedded watermarking scheme achieves copyright protection of images by embedding watermarks into the original images. This process will deteriorate the original image, so it is not suitable for medical images. In order to overcome this limitation, this paper proposes a geometrically invariant color medical image null-watermarking scheme based on quaternion polar harmonic Fourier moments (QPHFM), which achieves the copyright protection without changing the original medical image. First, a high-precision QPHFM computation method based on wavelet numerical integration is designed, which can effectively improve the computation precision. Then based on the precise QPHFM (PQPHFM) and chaotic map, a robust null-watermarking scheme for color medical images is proposed to protect the copyright of color medical images. This scheme uses the PQPHFM to construct feature images and its good stability and geometric invariance make the proposed null-watermarking scheme has good robustness and resistance against geometric attacks. Extensive simulation experiments show that the proposed scheme is highly robust in resisting common attacks and geometric attacks such as scaling, rotation, change of length-width ratio, and flipping. The performance of the proposed scheme is superior to that of similar robust null-watermarking schemes and other color medical image watermarking schemes.

New Image Watermarking Algorithm Based on DWT and Pixel Movement Function PMF

In this paper, we propose a new algorithm of image watermarking based on Discrete Wavelet Transform (DWT) including a function for pixels movement. The proposed algorithm uses DWT of two levels in order to compact a higher energy in component LL1, and Contrast Sensitivity Function (CSF) to improve the invisibility and robustness, the new Function of Pixel Movement (PMF) is applied to increase the security properties. Pixel Movement Function (PMF) is a function of N iteration inside each block, this function required a changeable key K calculated in each iteration N for the position of each block. Numerical experiments are performed to demonstrate that the proposed method can improve watermarking quality in terms of imperceptibility of watermark, capacity of insertion and robustness against different attacks such as Joint Photographic Experts Group (JPEG) compression, noise addition and geometrical attacks.

A novel watermarking algorithm for three-dimensional point-cloud models based on vertex curvature

A new blind watermarking scheme for three-dimensional point-cloud models is proposed based on vertex curvature to achieve an appropriate trade-off between transparency and robustness. The root mean square curvature of local set of every vertex is first calculated for the three-dimensional point-cloud model and then the vertices with larger root mean square curvature are used to carry the watermarking information; the vertices with smaller root mean square curvature are exploited to establish the synchronization relation between the watermark embedding and extraction. The three-dimensional point-cloud model is divided into ball rings, and the watermarking information is inserted by modifying the radial radii of vertices within ball rings. Those vertices taking part in establishing the synchronization relation do not carry the watermarking information; therefore, the synchronization relation is not affected by the embedded watermark. Experimental results show the proposed method outperforms other well-known three-dimensional point-cloud model watermarking methods in terms of imperceptibility and robustness, especially for against geometric attack.

A Hybrid Transforms-Based Robust Video Zero-Watermarking Algorithm for Resisting High Efficiency Video Coding Compression

With the rampancy of pirated videos, video watermarking for copyright protection has become a widely researched topic. In this paper, zero-watermarking is applied to videos for the first time to resist high efficiency video coding compression, which can improve the robustness of the watermarking algorithm and ensure the videos' quality. A robust video zero-watermarking algorithm based on the discrete wavelet transform, the all phase biorthogonal transform, and singular value decomposition is proposed. Utilizing the properties of hybrid transforms, robust features can be extracted from videos, and robust zero-watermarks can be constructed. Experimental results demonstrate that the proposed algorithm has strong robustness to high efficiency video coding compression attacks with different quantization parameters. In addition, the algorithm can also resist common image processing attacks, geometric attacks, frame-based attacks, and hybrid attacks. Compared with existing video watermarking algorithms, the proposed algorithm can more accurately and completely reconstruct watermark images.

A Robust Image Watermarking Scheme Using Z-Transform, Discrete Wavelet Transform and Bidiagonal Singular Value Decomposition

Watermarking is a widely used solution to the problems of authentication and copyright protection of digital media especially for images, videos and audio data. Chaos is one of the emerging techniques adopted in image watermarking schemes due to its intrinsic cryptographic properties. This paper proposes a new chaotic hybrid watermarking method combining Discrete Wavelet Transform (DWT), Z-transform (ZT) and Bidiagonal Singular Value Decomposition (BSVD). The original image is decomposed into 3-level DWT, and then, ZT is applied on the HH3 and HL3 sub-bands. The watermark image is encrypted using Arnold Cat Map. BSVD for watermark and transformed original image were computed, and the watermark was embedded by modifying singular values of the host image with the singular values of the watermark image. Robustness of the proposed scheme was examined using standard test images and assessed against common signal processing and geometric attacks. Experiments indicated that the proposed method is transparent and highly robust.

Research on Digital Watermarking Algorithm for Anti-geometric Attack

For the problem that the traditional digital watermarking algorithm is less robustness against geometric attacks, this paper introduces the related content of digital watermarking technology, which combs digital watermarking technology, digital watermarking attack technology and digital watermarking evaluation method, and summarizes the improved algorithms proposed in recent years. Next, the traditional wavelet transform algorithm and the improved algorithm based on DCT transform are selected for comparison experiments. The latter combines Arnold scrambling and SVD decomposition, which has better shear resistance. Finally, combined with the research status, the future research focus of digital watermarking algorithm is prospected.

Cross-Layered Embedding of Watermark on Image for High Authentication

Watermarking on multimedia gives more attention in research society. In this non-blind watermarking approach a watermark is reshaped and grouped into odd and even images. Next, wavelet is imposed on an original image and to enrich the robustness of the technique, watermarking process is enabled only in the upper diagonal regions of middle level wavelet coefficients. Further, the backward process is taken place to obtain the watermarked image. To prove ownership, original and watermarked image have undergone the same operation and acquire the copyright information. Experimental results indicate that the quality of the watermarked image is better also this algorithm is robust against filtering and geometrical attacks.

Feature-based synchronization correction for multilevel watermarking of medical images

Desynchronization attacks cause the global geometric displacements such as Rotation, Scaling, and Translation (RST) of the watermarked image. One of promising way is to embed hiding information in the stable to RST attacks regions defined by feature points. However, a multilevel protection of medical images supposes the embedding of Region Of Interest (ROI), electronic patient record, and fragile watermark. Volume of embedding information is too large to be stored in the restricted regions robust to attacks. First, a preliminary step is required for intensity equalization and detection of the cropped regions. Second, we use a synchronization correction of the global geometric attacks with the following compensation of possible local warping. The applied frequency transform such as digital wavelet transform or digital shearlet transform with single value decomposition is chosen due to a changeable volume of embedded information. Arnold’s transform is additional procedure increasing a security. Our experiments show that the proposed synchronization correction provides accuracy of the extracted watermarks up to 92%.

Video Watermarking System for Copyright Protection based on Moving Parts and Silence Deletion

In recent years, video watermarking has emerged as a powerful technique for ensuring copyright protection. However, ensuring the lowest level of distortion, high transparency and transparency control, integrity of the watermarked video, and robustness against attacks that can be applied to destroy the embedded watermark are important properties that should be satisfied in a watermarking system. In this paper, we propose a video watermarking system that hides a watermark in both the visual and audio streams to ensure the integrity of the watermarked video. Specifically, we propose the moving block detection (MBD) algorithm for hiding the watermark in the moving parts of the original visual stream of the video. The MDB algorithm ensures that a minimal amount of distortion is caused by embedding the watermark. The MBD uses entropy to find the moving parts of the visual stream to hide the watermark. The process of hiding in the visual stream is performed using DWT to ensure both transparency and resistance against attacks. We employ the power factors of DWT to control the level of transparency. In addition, we propose the silence deletion algorithm (SDA), which generates a pure original audio stream by removing the noise from the original audio stream to form the hiding place of the watermark within the audio stream. DCT is employed to hide the watermark within the pure original audio stream to ensure resistance against attacks. Under a threat model, which includes bilinear, curved, and LPF geometric attacks and compression and Gaussian noise non-geometric attacks, the experimental results demonstrated that the proposed system outperformed four similar systems: key-frame-, I-frame-, spread-spectrum-, and LBS-based systems.

Reversible data hiding methods in Integer Wavelet Transform

Reversible data hiding is art of concealing secret information such that cover media and secret information are both recovered without any information loss. In this paper high frequency sub-bands of integer wavelet transform are used for data embedding. All coefficients are used for embedding and to improve the security the embedding is carried out in frequency domain using spiral, sequential and random embedding method. The main objective of this research is to hide the maximum data with minimal distortion and to attain reversible hiding phenomenon both in cover and secret image. The experimental result shows the improved capacity, imperceptibility and complete reversibility attained on standard and medical images. The parameter of robustness has not been vastly studied for reversible data hiding and an attempt is made to check the same for basic attacks and results shows that it can withstand geometrical attack.