Narrow Results

As information technology develops rapidly and smart devices become popular, the traditional publishing industry is changing form. It has become very common for newspapers, books, magazines and pictures to transmit on the network. Because the network is easy to copy and spread text resources, the lawful interests of owners are liable to violate. In order to solve this problem, copyright protection technology represented by the text watermark has been invented. In this paper, a novel digital text watermarking algorithm utilizing word processing software is researched, which can ignore some faults in the documents to some extent. By means of this new algorithm, users can keep the copyright information in the reserved words of files and properly use the documents. The embedded watermark can be extracted and the copyright can be verified.

In this paper we introduce and develop a framework for visual data-hiding technologies that aim at resolving emerging problems of modern multimedia networking. First, we introduce the main open issues of public network security, quality of services control and secure communications. Secondly, we formulate digital data-hiding into visual content as communications with side information and advocate an appropriate information-theoretic framework for the analysis of different data-hiding methods in various applications. In particular, Gel'fand-Pinsker channel coding with side information at the encoder and Wyner-Ziv source coding with side information at the decoder are used for this purpose. Finally, we demonstrate the possible extensions of this theory for watermark-assisted multimedia processing and indicate its perspectives for distributed communications.

In this paper, we propose an improved autocorrelation function (ACF)-based watermarking that is robust against combined geometric and removal attacks. ACF-based watermarking is known to be effective against geometric attacks. In this watermarking scheme, both the embedded watermark and autocorrelation peaks of the watermark should survive a variety of attacks. However, the autocorrelation peaks are not strong enough. The proposed method improves the robustness of ACF-based watermarking by enhancing the strength of the autocorrelation peaks. Instead of the simple addition of a watermark to an image, the proposed watermark embedder uses the information of an original image more actively during the embedding process, so that the marked image has strong autocorrelation peaks. Experimental results show that the proposed scheme provides better robustness than conventional ACF-based watermarking against a variety of combined geometric-removal attacks.

Digital watermarking consists in embedding imperceptible information into a host signal. It has been proposed to solve problems as varied as the protection of the copyright, content authentication, fingerprinting and broadcast monitoring. This paper presents a new approach for audio watermarking using the QR factorization in wavelet domain. This approach is based on embedding a watermark binary image in the R matrices of low frequency blocks DWT coefficients of audio signal. In this algorithm, the watermark is embedded by applying a Quantization Index Modulation (QIM) process on the determined optimal sample for each matrix R. The watermark can be blindly extracted without the knowledge of the original audio signal. Experimental results show that the proposed audio watermarking scheme maintains high quality of the audio signal. Signal to Noise Ratio (SNR), Log Spectral Distortion (LSD) and Mean Opinion Score (MOS) are about 40 dB, 0.37 dB and 4.84, respectively. Moreover, the scheme is quite robust against common signal processing attacks such as noise addition, filtering and MP3 compression. In addition, this method ensures a secure extraction process by using a private key, making it suitable for secure applications such as copyright protection.

Robustness, especially to geometrical distortions is the present problem unresolved in the digital watermarking field. We describe an adaptive watermarking algorithm based on quantization in the DFT domain, which is robust to global geometrical distortions. The watermark was composed of a chaotic sequence, and it was embedded in the magnitudes of the DFT, and the embedded positions were the circle in the centered frequencies. The embedding strength adjusted to the properties of the original image. Watermark extraction was implemented without the original image. Experimental results show that our watermarking scheme is robust to global geometrical attacks, such as scaling, translation and rotation.

Today, many people are so conscious on intellectual property rights that lots of good solutions have been carried out to protect them. Digital watermarking is among of those ones. In this paper, we are going to describe a novel wavelet-based watermarking scheme which is designed to prevent the affection from any combination of attacks such as blurring, sharpening, noise, cropping, shifting, scaling, and rotating, that seek to eliminate the embedding watermark. In addition, the proposed watermarking system is very practical that the original image and watermark are not required during the watermark extracting phase, and the system can easily be extended to process different types of images. According to our experiments, our proposed system appears good results in its robustness.

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 wavelet transforms, an algorithm is proposed to scramble digital images. The algorithm changes both the location and the grey grade of image points. As a result, it achieves good scrambling effects and information security. When embedding digital watermarks, the fusion factors are adjusted to maximize fusion intensity using the critical threshold of human eyes for just noticeable difference (JND). Numerical experiments show good information hiding effects and high attack resistance of the hidden images, especially the ability to resist JPEG compression. The proposed algorithm can be used to protect the copyrights of digital images, and network transmission of encrypted hidden information.

The paper proposes a music copyright protection platform. It provides services of information hiding and extracting in the form of audio digital watermarking. The information hiding algorithms of this system are designed by combining wavelet transform, data scrambling and data fusion techniques, and encapsulated.

This paper presents an improved dual-watermarking scheme for two purposes: one is to protect the copyright of an image with a robust watermark, and the other is to verify integrity of ROI (region of interest) with a fragile watermark. These two watermarks are embedded in different domains with different techniques. The advanced robust watermarking correlating the watermark information sequence with the watermark position sequence is embedded into coefficients of ROB (region of backgrounds) after DWT. Then the fragile-watermarking is embedded into the LSB (least significant bit) of ROI in spatial domain. Both theoretic analysis and experiment show that our proposed dual-watermarking scheme is effective to affirm copyright and verify content integrity simultaneity; furthermore, robustness and security of the robust watermark are greatly improved with associated-sequences technique.

Digital video broadcasting is being increasingly adopted all over the world. This will necessitate proper digital copyrights management in order to assure fair returns to the content creators and reasonable prices for the subscribers. In this paper we propose a novel method to achieve video security and copyright protection in a broadcasting or a multicasting environment. The proposed method is an efficient solution for resolving the conflicting requirements of single copy transmission for broadcasting/multicasting and several copy transmissions for copyright protection by the broadcaster/multicaster. The proposed method supports dynamic join and leave and is not compute intensive and demands less resources from the broadcaster/multicaster compared to the existing methods. Essentially, the method relies upon the robust invisible watermarking, masking and conditional access techniques to achieve the desired result. The proposed method could be used for providing security and copyright protection for digital audio, image, video and also stored media (e.g. VCD, DVD) content.

In this paper, a new robust digital image watermarking algorithm based on wavelet is proposed. Instead of embedding watermark into a source image, this algorithm uses the source image and the watermark to generate a secret key which will be kept by a third party for copy right protection and watermark detection, and the quality of the source image is not degraded. Moreover, by dividing the wavelet coefficient bands of the source image into some sections and making use of average compare strategy, this algorithm is robust against a lot of attacks, including image compressing, Gaussian noise, blurring and cropping. Experiments in this paper illustrate its effectiveness and robustness.

With the development and widespread application of multimedia and network technologies, the protection of multimedia contentssuch as image, audio, and video becomes an urgent problem. As the powerful tool for copyright protection and authentication, digital watermark technology has gained wide attention and development. The principle of digital watermark technology is briefly introduced in this paper, and the copyright authentication scheme which applied in WWW is proposed.