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Steganography methods are considered to be one of the most common technologies for the protection of any digital data when transmitted over open communication channels at a given time. The solution of the problem of digital data protection using steganography methods is used not only by government services, but also by terrorist organizations. Therefore, the need for research, development and continuous improvement of steganoanalytical methods is becoming extremely important. The steganoanalytical algorithm based on the study of the singular decomposition of digital image matrix blocks is proposed in the paper. The main purpose of this paper is to increase the efficiency of digital image steganoanalysis, in the absence of a container, by developing a new steganoanalytical algorithm based on the study of the singular decomposition of digital image matrix blocks. As a result of a detailed study of the steganography algorithm using the singular decomposition of digital image matrix blocks, the statistical characteristics of the singular values of image matrix blocks are established. Based on the defined characteristics, the paper presents the main steps of the stegananoanalytical algorithm. As a criterion for assessing the effectiveness of the developed steganoanalytical algorithm, the probability of detecting additional information was used. Errors of the first and second type are considered. To compare the results of the developed steganoanalytical algorithm with existing algorithms in open access, the following applications are selected: XSteg; StegSpy. The software product "StegoAnalysis" has been implemented for the automated solution of the stegananalytical problem for digital image. [ABSTRACT FROM AUTHOR]

Video analysis is a very important tool in video surveillance systems with one or more cameras. Among the most promising features are tracking the movement of objects - tracking. The current state of development in the field of tracking is considered in the work. There are several types of trekking. Pixel Tracking is the tracking of the movement of a specific point (pixel) or group of points on the original video sequence. The result of this process is the trajectory of the pixel, corresponding to the movement of an object in the frame. Matchmoving is a complex process that allows you to create a three-dimensional scene with a digital camera based on the available video sequence, which exactly repeats the movement of a real camera. Motion Capture is a technology designed to determine the position and orientation of a real object in a virtual environment, determining the position and orientation of a real object in space is carried out using special sensors and markers. Each of these types of tracking can be used on its own or as part of more complex processes. The paper develops a modification of the camera motion detection algorithm, which works in the field of Pixel Tracking. The description of the main approaches to motion estimation is given, namely recursive raster algorithms, frequency domain algorithms, optical flow algorithms and block matching methods. The urgency of the work, its purpose and objectives are given. The paper describes a method of arranging blocks in a video sequence frame, which are used to calculate the movement of the camera. Similarity metrics are used to estimate the similarity of the blocks, namely the correlation coefficient. The paper describes the steps of the developed modification of the camera motion detection algorithm. The results of the modification of the camera motion detection algorithm are presented. The result of this work is an indicator of the visual quality of tracking in the form of a 2D image of the camera motion vector. [ABSTRACT FROM AUTHOR]

The protection of electronic information by cryptographic and steganographic methods, as well as their combination, is in great demand today. However, the new type of steganography - hash-steganography, fundamentally differs from classical steganography in that there is no need to embed messages in a container, no need to worry about the amount of information that can be transmitted in one container without compromising the visual stability of the image. A certain sequence of ordinary digital images is a message. The purpose of this work is to increase the efficiency of transmitting a secret message by modifying the hash-method of steganography. Previously, algorithms for obtaining hash functions of digital images have not been used to transmit messages, but they have found their application in hash-steganography. This paper compares two algorithms for obtaining hash codes and suggests a method of their application for transforming a text message into a sequence of digital images. It is a certain order of files transferred that is decisive in the decryption of a message. The symbols of the message are put in correspondence with the part of the hash code of the digital image. Thus, the necessary combination of files is formed, the number of which is equal to the number of symbols in the message. A comparative analysis of the two algorithms of the method has been performed. The results obtained have confirmed the effectiveness of the hash code algorithm based on the analysis of digital image DCT coefficients. This algorithm makes the method resistant to attack by compression, changing brightness and contrast, magnification and rotation. [ABSTRACT FROM AUTHOR]

In this paper the new method for digital image processing is proposed. Application of this method leads to decrease the conditioning number of the majority of matrix blocks obtained by standard partitioning as a result of preconditioning of the corresponding matrices. The proposed method preserves the reliability of the perception of the distorted image, which in the work is quantitatively estimated using the peak signal-to-noise ratio. The application of the proposed method as pre-processing of the cover image before steganography transformation makes it possible to extend the application domain of the steganography algorithm based on the sign-insensitivity of the singular vectors of blocks of the digital image matrix developed by one of the authors earlier. The preconditioning of the block matrix occurred after its precoding. The result of precoding is a symmetric positive-definite sparse matrix, which is mapped to the image block. The positive definiteness and sparsification of obtained matrix make it possible to use as its preconditioner the incomplete Cholesky factorization. The results of the computational experiment are presented. [ABSTRACT FROM AUTHOR]

In this paper it is proposed basics of a new approach to identify cloning results, conducted in digital images, in additional disturbing influences conditions in a digital image after cloning, that may be considered as lossy compression, add noise, blur, etc. The approach is based on identifying the comparability of the surface parts, which is put into correspondence the analyzed image appropriate clones and its preimage. The surface is determined by the graph of the interpolation spline, approaching the function of the image, and the elements of the image are regarded as the interpolation nodes. It is proved that as the main quantitative characteristics of such comparability is advisable to use the volume of a cylindrical body with generator parallel to the axis OZ, bounded from above corresponding part of the interpolation function graph, bounded below - plane XOY. [ABSTRACT FROM AUTHOR]

In this paper we study the behavior of function of standard deviation of the discrete cosine transform coefficients from their requantized values for the original and forged digital images. The forgery was conducted under different conditions. A new method for the detection and localization of digital image forgery is developed. In addition, it is applied for detection and localization of small sized forgery regions. [ABSTRACT FROM AUTHOR]