Dual-channel opto-electronic surveillance systems which operate in visible and infrared spectrum ranges are widespread. Their analysis and design needs suitable tools. A simplified physics-mathematical model of a dual-channel optoelectronic surveillance system was developed to determine energy resolution of the system. Noise equivalent brightness difference and noise equivalent temperature difference were used to define the ability of television and thermal imaging systems to detect objects. As an example of applying the model an algorithm of spectral channel selection depending on the conditions of surveillance was developed.
A function-based approach of object rendering based on perturbation functions and 3D textures with the use of graphics processing units is proposed. To generate the terrain and the control in levels of detail, the similar technique as that for color textures is used. A method of real-time rendering of 3D clouds is described. For this aim, it is proposed to form 3D textures by means of pre-processing of the inner cloud pattern and volume-oriented rendering.
Among the various characteristics of infrared radiation, the degree of polarization is not often used in radiation analysis. The main reason is that polarization is less informative characteristic compared to others for most practical tasks. Also obtaining polarized radiation in infrared spectrum is relative complex and expensive act. In some cases, such as remote sensing, the improvement of spatial, radiometric and spectral resolution approaches it’s physical limit. It becomes relevant to obtain additional information of a different nature, such as polarization information. Modern infrared radiation polarizers based on diffraction gratings are quite expensive. The article explores the possibility of creating infrared polarizers based on a planeparallel plate, to which radiation falls at an Brewster angle. It is shown that the polarizer operating on transmittance will be more efficient than reflecting radiation polarizer, since it does not deviate the optical axis by a significant angle. Such a polarizer provides a polarization degree of 90% and a transmittance of about 50%.
This paper investigates the relationship between the integral equation and Kirchhoff approximation in the diffraction theory of coherent radiance. The spectrum of the reflected wave is formed in the far field (Fraunhofer zone) and the solution is to Fourier transform of effective reflectance coefficient of a surface. In the paper, the analytical relationship between the method of solving an integral equation and the Kirchhoff approximation has been proven. It helps to define the structure of the field of diffracted waves in a Fraunhofer zone for coherent scattered light. The analytical equations for calculation of the average value of intensity scattering field and the mirror reflection coefficient of a rough surface have been obtained. Analysis of the components of the scattering coherent light coming from a metal surface has been improved. It helps to specify the data processing algorithms for evaluation of statistical characteristics of rough surfaces.
Algorithm of Ramer–Douglas–Peucker for piecewise approximation was used for image multilevel segmentation. The cumulative histogram was chosen as a function for approximation. The developed algorithm was applied to the satellite map images to divide clouds of different intensity. The map images of clouds with different intensity were clustered to obtaine cloudiness values and classification.