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In this paper we present an improved support vector machines (SVMs) watermarking system for still images and video sequences. By a thorough study on feature selection for training SVM, the proposed system shows significant improvements on computation efficiency and robustness to various attacks. The improved algorithm is extended to be a scene-based video watermarking technique. In a given scene, the algorithm uses the first h' frames to train an embedding SVM, and uses the trained SVM to watermark the rest of the frames. In the extracting phrase, the detector uses only the center h frames of the first h' frames to train an extracting SVM. The final extracted watermark in a given scene is the average of watermarks extracted from the remaining frames. Watermarks are embedded in l longest scenes of a video such that it is computationally efficient and capable to resist possible frames swapping/deleting/duplicating attacks. Two collusion attacks, namely temporal frame averaging and watermark estimation remodulation, on video watermarking are discussed and examined. The proposed video watermarking algorithm is shown to be robust to compression and collusion attacks, and it is novel and practical for SVM-applications.

A novel sparse domain-based information hiding framework is proposed in this paper to attach the watermarking signal to the most significant sparse components of the host signal over the pre-defined overcomplete dictionary. The adaptive sparse domain can be utilized to embed watermarking logo with better security and robustness. This can be realized owing to the fact that, not only the sparse domain can be customized from the given samples, but also the sparse transform coefficients of the original watermarking signal can be embedded, which provides inherent privacy. This paper provides two kinds of methods that embed watermark directly and embed the sparse representation coefficients of watermarking logo, and analyzes the condition of uniqueness of the sparse solution. Experimental results demonstrate the superiority of the proposed sparse domain digital watermarking technique over the traditional frequency domain or spatial domain schemes.

This paper presents a copyright owner detection technique for images and graphics. A digital time-stamped signature for this copyright identification technique is also introduced in this work. The secret key, used to compute the watermark, is generated from the extracted features of the host images in the proposed scheme. The proposed algorithm enables the successful revealing of watermarks under several attacks, such as filtering, lossy compression, cropping, rotating, and so on. In particular, our method is not only suitable for ordinary natural images, but can also be applied to cartoon graphics. Most importantly, the proposed scheme can be applied to the media in which distortion is not allowable, such as medical images, source code of programs, and so on.

Data mining aims at extracting knowledge from data. Sometimes this requires the data owner to make data available to the data analyst. Unless the analyst is trusted by the data owner, the latter may wish to have his intellectual property rights protected. Watermarking is a way to provide some protection, not only for multimedia data, but also for numerical data. It consists of imperceptibly embedding a secret mark into the data to be protected. The mark can later be used to resolve any subsequent disputes on data ownership. This paper presents a watermarking method that embeds a watermark into each attribute of a multivariate continuous numerical dataset. This watermarking method is shown to be robust against random noise addition attacks. Data quality is assured to the extent that the watermarked data nearly preserve the attribute means and the covariance matrix from the original dataset. Our proposal is the first known watermarking system for multivariate numerical datasets with such robustness and quality properties.

Digital watermarking has been proposed for the protection of digital medias. This paper presents two watermarking algorithms for binary images. Both algorithms involve a blurring preprocessing and a biased binarization. After the blurring, the first algorithm embeds a watermark by modifying the DC components of the Discrete Cosine Transform (DCT), followed by a biased binarization, and the second one embeds a watermark by directly biasing the binarization threshold of the blurred image, controlled by a loop. Experimental results show the imperceptibility and robustness aspects of both algorithms.

In this paper, we propose a watermarking scheme for non-uniform B-spline (NUBS) surface. Firstly, we first do sampling on a NUBS surface and get the sample points, then the watermark is embedded into the DCT coefficients of the sample points and the watermarked sample points are transformed back, finally the watermarked surface is reconstructed from watermarked sample points using global interpolation. A sign correlation detector is used to test for the presence of the watermark, and the original surface is not required at this stage. Experimental results show that our algorithm can preserve the shape of the original surface within a specified error, and that it is robust against attacks including knot insertion, order elevation, addition of white noise, rotation, scaling, translation and further watermarking.

This paper presents a new robust reference watermarking scheme based on wavelet packet transform (WPT) and bidiagonal singular value decomposition (bSVD) for copyright protection and authenticity. A small gray scale logo is used as watermark instead of randomly generated Gaussian noise type watermark. A reference watermark is generated by original watermark and the process of embedding is done in wavelet packet domain by modifying the bidiagonal singular values. For the robustness and imperceptibly, watermark is embedded in the selected sub-bands, which are selected by taking into account the variance of the sub-bands, which serves as a measure of the watermark magnitude that could be imperceptibly embedded in each block. For this purpose, the variance is calculated in a small moving square window of size S_p × S_p (typically 3 × 3 or 5 × 5 window) centered at the pixel. A reliable watermark extraction is developed, in which the watermark bidiagonal singular values are extracted by considering the distortion caused by the attacks in neighboring bidiagonal singular values. Experimental evaluation demonstrates that the proposed scheme is able to withstand a variety of attacks and the superiority of the proposed method is carried out by the comparison which is made by us with the existing methods.

Traditional singular value decomposition (SVD)-based watermarking schemes, already exist for watermark embedding on the image as a whole. In this paper, a chaos-based hybrid watermarking scheme that combines the Fourier transform and the SVD is proposed. Instead of modifying the original cover image to embed the watermark, a reference image is formed in the proposed scheme to embed the watermark. The watermark is embedded by modifying the singular values of the reference image. The watermark extraction process is semi-blind, i.e. it does not require the original image. Chaotic map is used to shuffle the pixel positions of the image, which can be used as a secret key to improve the security of the algorithm. The security of the scheme is further strengthened by applying Zig-Zag scan on the watermark before embedding. A series of experiments is conducted to prove the fidelity and robustness property of the proposed scheme. Experimental results show that our scheme is strong enough to resist common image-processing attacks, geometric distortions, and some composite attacks. The results also show that our scheme outperforms related works in most cases.

Image watermarking is one of the most accepted solutions protecting image authenticity. The method presented in this paper not only provides the desired outcome also efficient in terms of memory requirements and preserving image characteristics. This scheme effectively utilizes the concepts of block truncation coding (BTC) and lifting wavelet transform (LWT). The BTC method is applied to observe the binary watermark image corresponding to its gray-scale image. Whereas, the LWT is incorporated to transform the cover image from spatial coordinates to corresponding transform coordinates. In this, a quantization-based approach for watermark bit embedding is applied. And, the extraction of binary watermark data from the attacked watermarked image is based on adaptive thresholding. To show the effectiveness of the proposed scheme, the experiment over different benchmark images is performed. The experimental results and the comparison with state-of-the-art schemes depict not only the good imperceptibility but also high robustness against various attacks.

This paper presents a novel adaptive watermarking based on iteration mapping and image content. An original image is divided into non-overlapped blocks, which are analyzed by means of fractal dimension, and the feature blocks which contain edges and textures are further classified by variance characteristics into three different parts: edges, weak textures, and strong textures. The original watermark is a distinguishable gray image, which is scrambled and amended to form a watermark signal to be embedded. DCT is applied to all the original image blocks and the formed watermark is embedded into their middle-frequency coefficients with different strength. Performance analysis of adaptive watermark extraction is presented in details. Experimental results show that this algorithm is able to achieve a watermarked image with good perceptual invisibility, high security and strong robustness.

The Fourier transform is undoubtedly one of the most valuable and frequently used tools in signal processing and analysis but it has some limitations. In this paper, we rectify these limitations by proposing a newer version of Fourier transform, namely, Distributed Multiresolution Discrete Fourier Transform (D-MR-DFT) and its application in digital watermarking. The core idea of the proposed watermarking scheme is to decompose an image into four frequency sub-bands using D-MR-DFT and then singular values of every sub-band are modified with the singular values of the watermark. The experimental results show better visual imperceptibility and resiliency of the proposed scheme against intentional or unintentional variety of attacks.

We propose a new digital image watermarking method based on the dyadic wavelet packet transform (DYWPT) and fast interval arithmetic (IA) techniques. Because the DYWPT has a redundant representation, like the dyadic wavelet transform (DYWT), the amount of information that the watermark must contain is greater than in the case of methods based on ordinary discrete wavelet transforms (DWTs) and the discrete wavelet packet transform (DWPT). However, the order of the high frequency components is not necessarily the same as the order of their frequency domain. Therefore, in our approach, we rearrange the order of the high frequency components in descending order of frequency components and embed a watermark selectively into higher frequency components. Our watermark is a ternary-valued logo that is embedded into higher frequency components through use of the DYWPT and fast IA techniques. We describe our watermarking procedure in detail and present experimental results demonstrating that our method produces watermarked images that have better quality and are robust with respect to various types of attacks, including marking, clipping, median filtering, contrast tuning (histeq and imadjust commands in the MATLAB Image Processing Toolbox), addition of Gaussian white noise, addition of salt & pepper noise, JPEG and JPEG 2000 compressions, rotation, and resizing.

In watermarking schemes, image can be considered as a communication channel to transmit messages. This paper presents a new adaptive capacity analysis scheme for image watermarking, realizes a content adaptive watermarking algorithm invisibly embedding the strongest watermark, and discusses the watermarking capacity of blind watermarking and non-blind watermarking. This paper also analyzes the relation between watermarking capacity and watermarking detection bit error rate (BER), and derives the relation between capacity and the limit of BER. According to the result of research, watermarking detection BER mainly influenced by the watermarking average energy and watermarking capacity. The BER rises with the increase of watermarking capacity.

We propose a robust digital watermarking technique based on Principal Component Analysis (PCA) and evaluate the effectiveness of the method against some watermark attacks. In this proposed method, watermarks are embedded in the PCA domain and the method is closely related to DCT or DWT based frequency-domain watermarking. The orthogonal basis functions, however, are determined by data and they are adaptive to the data. The presented technique has been successfully evaluated and compared with DCT and DWT based watermarking methods. Experimental results show robust performance of the PCA based method against most prominent attacks.

An adaptive digital watermarking algorithm was proposed, in which Gold codes was applied, and the watermark was inserted into the wavelet domain of the carrier image according to the analysis of human visual system. The robustness and efficiency of the algorithm is enhanced because of the introduction of CDMA. At first, Gold codes were generated by m-sequences, and the watermark was encoded through CDMA technique, then the encoded information was inserted into the wavelet domain adaptively according to JND (Just Noticeable Difference). Experiment results show that the embedded watermark is invisible, and can resist to Gaussian Noise, JPEG compression and median filtering.

In this paper, we proposed a strong watermark algorithm for digital image protection based on wavelet. Instead of adding watermark into source image, we use it to generate a standard key to identify the copyright and ownership. The key will be sent to a third party, and there will be no modification to the source, which means this algorithm guarantees perceptual invisibility. We use a 256-level image as watermark and convert every pixel into an 8-bit binary; it has been proven that both stability and amount of embedded information were increased. Besides, taking full advantage of average compare is doubly enhanced the strength. We will illustrate its effectiveness and robustness by showing the detecting result after experimental attacks.

Based on Deepa Kundur's paper [1], in this paper we present an improved version with stronger robustness. Instead of random picking, we select embedding position according with HVS characteristic, and by mathematical deduction, specific conditions are given to make sure the algorithm works well when the quantified distance is tiny or even 0, which is impossible for the original algorithms. In this way, both robustness and imperceptibility are guaranteed. Experiment results show that proposed algorithm greatly enhanced the ability to against various attacks, especially cropping, as well as offering superior advantages over Deepa's algorithms.

This paper based on the feasibility of using rough sets theory in digital image watermarking technology. The carrier image was regarded as a knowledge system, and condition attributes and decision attributes are represented by some visual characteristics. Embedding method of watermark information which is adapted to the visual demand was summarized after objective analyses. Results of the experiments carried on test images show that the embedding rules acquired according to this paper have good effect.

The first application of singular value decomposition(SVD) to digital watermarking in 2002[1] has attracted scholars' attention ever since. Currently, because of the stability of singular value decomposition and the algebraic characteristics of images, many robust watermarking algorithms based on singular value decomposition have been proposed. This paper introduces the application of SVD to a digital watermarking algorithm. Through four experiments, the paper shows that the SVD-based algorithms evoke problems of uncertainty, as copyright ownership cannot be determined.

The present paper discusses the work of digitization of cultural heritage of India. Non-contact digitizing system is the only practical choice for high resolution scanning of sculptures and artifacts. They collect from 20 to more than 25,000 points per second and provide resolution of better than O.OOl-inch to 0.020-inch, depending on technology. Tlhis work is carried out at Indian Institute of Technology, Kanpur and in Allahabad University and focuses mainly on Buddhist deities Hariti and Gajlaxmi. We will discuss about the digitization of these artifacts, concept of Rapid Prototyping, Reverse Engineering. In the paper we will also discuss the detail of the development of the Rapid Prototype of Buddha statue in FDM (Fused Deposition Modeling). Certain research issues pertaining to reconstruction and databases are also discussed.