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Abstract: According to the characteristic of large aperture static interference imaging spectrometer (LASIS), a non-linear orientation prediction three-dimensional (3D) wavelet transform method is proposed in this paper on the basis of the 3D orientation prediction wavelet transform method proposed by Li, Ma and Wu in 2008 [1]. The method proposed in this paper still combines directional prediction into 3D lifting wavelet transformation, but compared with the 3D orientation prediction wavelet transform method, it made a breakthrough in the limitation that the orientation predicted must be a straight linear direction. The experimental results showed that this method improved the performance of wavelet obviously, especially on the LASIS image with quite severe and unstable directional characteristic as seen in the study of Ma and Ma (2009) [2]. Meanwhile, the characteristic of spectrum image recovered by the proposed method also possessed better performance. [Copyright &y& Elsevier]

Abstract: In this paper, a high efficient adaptive LBG VQ (vector quantization) method is proposed, which is an improved version of the expansion LBG VQ method [1] (proposed in 2009)and exploits the shortest distance from a point to line segment. Moreover, the proposed method is used on the lossless compression of LASIS (Large Aperture Static Imaging Spectrometer) interferential multi-spectral images. Compared with the expansion LBG VQ method proposed in 2009, the experimental results showed that the adaptive LBG VQ method improved the compression performance obviously. And the experiment also showed that when using these LBG VQ methods above without Dual-Direction Prediction [2], the entropy generated by expansion LBG VQ method [1] sometimes will be larger than that generated by traditional LBG VQ method [3], and when using these LBG VQ methods above after Dual-Direction Prediction [2], CR (compression ratio) generated by expansion LBG VQ method [1] sometimes will be less than that generated by traditional LBG VQ method [3], while the entropy generated by the method proposed in this paper will be much less than that generated by either traditional LBG VQ method [3] or the expansion LBG VQ method [1], and CR generated by the method proposed in this paper will be much larger than that generated by either traditional LBG VQ method [3] or the expansion LBG VQ method [1]. [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]