METHOD OF DYNAMIC IMPLEMENTATION OF A ROBUST DIGITAL WATERMARK IN VIDEO DATA

В статье рассматривается модифицированный метод внедрения цифровых водяных знаков в видеоданные, заключающийся в дополнении уже известных методов новыми функциями, базирующихся на принципиальных отличиях видеопотока от статичной фотографии. The article discusses a modified method of introducing digital watermarks into video data, which consists in supplementing the already known methods with new functions based on the fundamental differences between the video stream and static photography.

Development of methods for generation of digital watermarks resistant to distortion

Active attacks and natural impacts can lead to two types of image-container distortions: noise-like and geometric. There are also image processing operations, e.g. scaling, rotation, truncation, pixel permutation which are much more detrimental to digital watermarks (DWM). While ensuring resistance to removal and geometric attacks is a more or less resolved problem, the provision of resistance to local image changes and partial image deletion is still poorly understood. The methods discussed in this paper are aimed at ensuring resistance to attacks resulting in partial image loss or local changes in the image. This study's objective is to develop methods for generating a distortion-resistant digital watermark using the chaos theory. This will improve the resistance of methods of embedding the digital watermark to a particular class of attacks which in turn will allow developers of DWM embedding methods to focus on ensuring the method resistance to other types of attacks. An experimental study of proposed methods was conducted. Histograms of DWMs have shown that the proposed methods provide for the generation of DWM of a random obscure form. However, the method based on a combination of Arnold’s cat maps and Henon maps has noticeable peaks unlike the method based on shuffling the pixels and their bits only with Arnold’s cat maps. This suggests that the method based only on Arnold’s cat maps is more chaotic. This is also evidenced by the value of the coefficient of correlation between adjacent pixels close to zero (0.0109) for color DWMs and 0.030 for black and white images.

Steganographic method based on hidden messages embedding into Bezier curves of SVG images

The description of the steganographic method for embedding the digital watermark into image vector files of the SVG format is given. Vector images in SVG format can include elements based on Bezier curves. The proposed steganographic method is based on the splitting of cubic Bezier curves. Embedding hidden information involves splitting cubic Bezier curves according to the digital watermark given as numerical sequence. Algorithms of direct and reverse steganographic transformation are considered for proving the authenticity and integrity of a digital vector image. The StegoSVG library has been developed to implement forward and reverse steganographic transformations. The developed desktop application that implements the method is briefly described.

A new method for watermarking color images using virtual hiding and El-Gamal ciphering

One of the important issues in the era of computer networks and multimedia technology development is to find ways to maintain the reliability, credibility, copyright and non-duplication of digital content transmitted over the internet. For the purpose of protecting images from illegal usage, a watermark is used. A hidden digital watermark is the process of concealing information on a host to prove that this image is owned by a specific person or organization. In this paper, a new method has been proposed to use an RGB logo to protect color images from unlicensed trading. The method depends on retrieving logo data from specific locations in the host to form a logo when the owner claims the rights to those images. These positions are chosen because their pixels match the logo data. The locations of matching pixels are stored in a table that goes through two stages of treatment to ensure confidentiality: First, table compression, second, encoding positions in the compressed table through El-Gamal algorithm. Because the method depends on the idea of keeping host pixels without change, PSNR will always be infinity. After subjecting the host to five types of attack, the results demonstrate that the method can effectively protect the image and hidden logo is retrieved clearly even after the attacks.

Research of the Stegosignal Propagation through the Acoustic Environment

The paper considers two main applications of stegosystems: as a digital watermark, for copyright protection, and as a method for secretly transmitting information through an acoustic environment. A stegosystem is studied theoretically and experimentally when information is transmitted over different distances in an acoustic medium in the presence of extraneous noise. Nowadays great attention is paid to the protection of intellectual property. Illegal distribution of media content, including copies of musical compositions, is widespread and reaches unprecedented proportions. Protecting audio files from unauthorized copying and using becomes increasingly important. Digital watermarks are a promising method for solving this problem. The purpose of the article is to develop an effective method for protecting audio files from illegal use by embedding a digital watermark (DW). After detection the illegal distribution of their product, the copyright holder will be able to track the presence of the digital watermark and apply to the court for damages.

Development of a method for improving stability method of applying digital watermarks to digital images

A technique for increasing the stability of methods for applying digital watermark into digital images is presented. A technique for increasing the stability of methods for applying digital watermarks into digital images, based on pseudo-holographic coding and additional filtering of a digital watermark, has been developed. The technique described in this work using pseudo-holographic coding of digital watermarks is effective for all types of attacks that were considered, except for image rotation. The paper presents a statistical indicator for assessing the stability of methods for applying digital watermarks. The indicator makes it possible to comprehensively assess the resistance of the method to a certain number of attacks. An experimental study was carried out according to the proposed method. This technique is most effective when part of the image is lost. When pre-filtering a digital watermark, the most effective is the third filtering method, which is averaging over a cell with subsequent binarization. The least efficient is the first method, which is binarization and finding the statistical mode over the cell. For an affine type attack, which is an image rotation, this technique is effective only when the rotation is compensated. To estimate the rotation angle, an affine transformation matrix is found, which is obtained from a consistent set of corresponding ORB-descriptors. Using this method allows to accurately extract a digital watermark for the entire range of angles. A comprehensive assessment of the methodology for increasing the stability of the method of applying a digital watermark based on Wavelet transforms has shown that this method is 20 % better at counteracting various types of attacks

An error resilient scheme of digital watermarking for MP3 streaming audio

The recent massive growth of networked multimedia has caused problems relative to the protection of intellectual property rights. This is particularly true to MP3 audio data. These types of protection systems involve the use of both encryption and authentication techniques. In this thesis we describe a form of authentication known as digital watermarking. A novel scheme to embed digital watermark to MP3 music using Quantization Index Modulation (QIM) algorithm is proposed in the thesis. A pseudorandom key is generated as watermark message which is embedded into MDCT coefficients of MP3 directly. At the receiver, the MP3 is decoded partially and the watermark is extracted frame by frame. Furthermore we discuss the recovery method of the watermarking after the watermarked MP3 audio is streamed on the network. Distributing digital watermark on Internet through streaming audio is a challenging task because most digital watermarking algorithm is very sensitive to packet loss due to the associated synchronization problem. On the current Internet, packet loss is almost inevitable since its backbone protocols are operating in best-effort manner and do not guarantee the successful delivery of data packets. Therefore it is very essential to develop a scheme that resists the damage caused by packet loss to audio watermarks. Our robust watermarking scheme can recover the watermarks despite the packets loss (loss rate equal or less than 10%) on the networks. In addition, we integrate the classical Forward Error Correction (FEC) code in our watermarking scheme, which achieves 100% recovery rate when the packet loss is 6%.