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Aim to the problem of initial epipolar distance transformation algorithm is sensitive to illumination and depth discontinuous, an improved stereo matching algorithm is proposed. In Delta-Gama log-chromaticity space, Gamma correction coefficient is computed firstly according to raw disparity map which is used to Modified the similarity function bandwidth. Secondly, by employing image structure and color features, the segment of epipolar is obtained adaptively. At last, final disparity map is acquired by belief propagation method. Experimental results demonstrate the effectiveness of the proposed transform in illumination change regions and discontinuities regions. The matching rate of proposed algorithm is improved about 60%, comparing with the initial epipolar distance transformation algorithm and state-of-art algorithm such as ANCC(Adaptive Normalized Cross Correlation). [ABSTRACT FROM AUTHOR]

Airborne aiming pod is mainly used for searching, capturing and tracking the target indicated by the laser, and then dropping the laser-guided weapons precisely to complete the close-range support attack or dual-aircraft cooperative instruction/attack. High-precision laser beam pointing technology is the core of the airborne aiming pod, and the accuracy of it is fatal for the realization of the final tactical index. In this paper, the factors affecting the beam pointing accuracy based on the research of airborne aiming pod platform are analyzed. At first, the composition of the pod system and the motion coupling of the composite axis pod are introduced; and then the beam pointing algorithm under the external guidance combined with aircraft disturbance and the effects of atmospheric turbulence and atmospheric attenuation on beam quality, including optical axis drift, beam spread and intensity distribution variation are discussed. Finally, the performance of the pod servo system is simulated and verified in Simulink. The simulation result of the real flight situation with disturbance moment shows that the pointing accuracy of the airborne aiming pod can reach 0.0075 degrees. The data analyzed in this paper can provide technical reference for other aiming photoelectric platforms. [ABSTRACT FROM AUTHOR]

In this paper, one active polarization imaging technique is introduced to enhance the contrast between the target and the sky to overcome the environmental interference such as cloud and fog in the long-range detection of air vehicles. At first, the theory of the whole system, the selection of detection system and the wavelength of laser, and the brief design of the optical system are described. Secondly the selection of the laser power is derived based on the elements such as atmosphere attenuation, and the sensitivity, image contrast and signal-to-noise ratio in the detector. Then the polarization imaging mechanism of the full aperture polarization measurement platform is analyzed. Finally a nonlinear differentiator is proposed to improve the speed stability in the tracking to ensure high imaging quality. The purpose of this paper is to lay a theoretical foundation for active polarization imaging technology and to promote its engineering application in shooting range and other fields. [ABSTRACT FROM AUTHOR]

For realizing the engineering application of key technologies in the long-range active polarization imaging system, an experimental platform is built to study the static active polarization imaging technology and related image fusion algorithm in the smoke and dust environment. In the experiments, 532 nm CW laser is used as illumination source after collimation and beam expansion, metal bullet model is used as detection target, smoke environment is created through smoke generator in organic glass hood, polarization direction can be rotated by the polarizer, the images are collected by Lumerera-LM135 camera. The analysis and handling on the images are conducted by the use of the MATLAB software. In the aspects of image information entropy, average gradient, spatial frequency and standard deviation, the polarization imaging effects in various environments are quantitatively compared and analyzed, and the imaging advantages of laser illumination and polarization imaging technology in smoke and dust environment and dim conditions are verified. In order to further improve the imaging quality of active polarization imaging technology, a polarization image fusion algorithm based on fuzzy adaptive is proposed after analyzing a large number of data acquired in the experiment. The experimental results show that the active polarization imaging technology and the improved image fusion algorithm can improve the detection distance of optical system and image contrast, expand the digestible information of images for the long-range dim target imaging in low visibility environment, and provide important data reference and technology support for the application of this technology in shooting range. [ABSTRACT FROM AUTHOR]