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Various methods of background compensation in a sequence of images are analyzed under conditions where the main change in the background is its spatial shift. Methods of estimating the background in a current frame by means of interpolation of data contained in the previous frames are considered. Analytical estimates of the compensation error are given as functions of the spectral properties of images and interpolation methods. Results of numerical experiments are reported, which confirm these analytical estimates and show that the use of local interpolating filters allows extremely low errors of compensation.

An algorithm is proposed for segmenting anisotropic image based on estimates of the local orientation of textures obtained using a gradient structural tensor. A mixture of a uniform distribution and a von Mises distribution is used as the estimate model. An estimation algorithm for the unknown parameters of the mixture based on trigonometric moments is obtained. Examples are given demonstrating the effectiveness of the segmentation algorithm in identifying textures with one dominant direction.

This paper presents an algorithm for the reconstruction of digital color image component signals corrupted by impulse noise by exploiting interchannel redundancy. Results of numerical studies have shown that intercomponent gradient reconstruction is superior to median filtering in the accuracy of reconstruction of lost or corrupted color image elements. Processing of a three-component digital color image has shown the efficiency of the proposed algorithm.

The basic methods of detecting individual tonal components and algorithms for their implementation are considered; their advantages and disadvantages are analyzed. A generalization of the one-bin sliding parametric discrete Fourier transform is proposed. The algorithm implementing this transformation significantly reduces the number of operations required for the algorithm to enter the sliding measurement mode.

An algorithm of constructing displacement vector fields, based on the incremental approach to estimating displacements of image fragments, is proposed. Application of this algorithm for processing model and experimental optical images is analyzed. Noise immunity of the incremental algorithm for determining displacements is compared with that of the combined algorithm developed by the authors. It is shown that the proposed incremental algorithm ensures a more noise-immune estimate of displacements in processing images of a deformation relief essentially varying in time.

A method of synthesis and analysis of regression estimate of the multidimensional probability density under conditions of a large volume of initial statistical data is proposed. Its asymptotic properties are investigated. On this basis, the relationship between the efficiency factor of the proposed estimate and the parameters of the procedure of expansion of initial data is established.

A new method is proposed for suppressing artifacts of tomographic reconstruction. The method is based on selective estimation of the mathematical expectation of the residue between phantoms simulating a random distribution and their tomograms. The method is justified theoretically and is supported by a computational experiment.

This paper presents a study of an infinite-server multistage queuing system with a highrate renewal arrival process and arbitrary service time. It is shown that under the condition of infinitely increasing rate of arrival, the multidimensional distribution of the probabilities of the number of servers employed to service stages of the system can be approximated by a multidimensional normal distribution. The expectation vector and the covariance matrix of this distribution were obtained.

An experimental study of the effect of asymmetric strain of a photonic crystal in the form of changes in the slope of crystal planes during its filling with a gas analyte is performed. This effect is used as a basis for creating a model of a relatively inexpensive selective highly sensitive fast-response sensor of ammonia sensor.

A technique of calculating the spectral characteristics of model holographic photonic crystals (PhCs), including those with spatial structure defects, is presented. This technique is based on the model of a multilayer system of thin dielectric films and the calculated refractive index profile of the PhC structure along selected crystallographic directions. The calculation results of the studied characteristics for various examples of PhC structures are given.