Lin Z.,Anhui University of Science and Technology |
Tao J.,Anhui University of Science and Technology |
Zheng Z.,Huayin Ordnance Test Center
International Conference on Signal Processing Proceedings, ICSP | Year: 2012
In this paper, we introduce a new approach for general purpose reduced-reference image quality assessment (RRIQA) based on the average directional information (ADI), which is obtained from complex wavelet coefficients. The dual-tree complex wavelet transform (DT-CWT) possessing more excellent properties than the discrete wavelet transform (DWT) such as shift invariance and multi-directional selectivity is used to produce complex wavelet coefficients. Then the inter-coefficient product (ICP) is computed to represent the feature orientation (through the complex phase) and the feature strength (through the complex magnitude). We consider the distortion progress affect the directional features in the reference image, so the difference between the ADI of the distorted image and the reference image can be an indicator that quantizes the degree of degradation. The experiments are performed based on LIVE database, and the results show that the proposed approach is comparable to PSNR and some of the state-of-the-art RR approaches, meanwhile has relatively small size of RR features. © 2012 IEEE.
Guo D.,Lanzhou University |
Guo D.,Huayin Ordnance Test Center |
Dong Z.,Lanzhou University |
Luo C.,Lanzhou University |
And 3 more authors.
RSC Advances | Year: 2014
A novel selective fluorescent chemosensor L based on rhodamine B derivative has been designed and synthesized to optically detect Cu2+ and S2- in aqueous buffer solution. The fluorescence of L was excited by Cu2+ with a 1:1 binding ratio, and could be used as a "turn-on" type sensor. Otherwise, the emission band would undergo a slight red-shift. Once binding with Cu2+, the copper complex can exhibit high selectivity for S2-. Upon addition of Cu2+, the color of the chemosensor L changes from colorless to pink. Additionally, the resulting pink solution changes to colorless immediately upon the addition of S2-. However, no phenomenon change could be observed in the presence of other anions. Conclusively, the color changes suggest that sensor L could serve as a "naked-eye" sensor for Cu2+ and S2-. © 2014 The Royal Society of Chemistry.
Wu H.,Xian Jiaotong University |
Wu H.,Huayin Ordnance Test Center |
Zhang C.,Xian Jiaotong University |
Bai X.,Xian Jiaotong University
Optics Communications | Year: 2010
A complete description of polarization and transmission of light in a uniaxial birefringent plate with arbitrary crystal axis direction is detailedly presented. A general case with nonnormal incidence in spatial domain is considered. The universal theoretical model is build up by referring to all the impact factors including the incident angle, the incident wavelength, the azimuth angle, and the optical axis direction of crystal plate. The simulated results show that the ordinary ray and extraordinary ray in birefringent crystal have unique polarization direction and distinct energy transmission property, respectively. The explicit representation in this paper allows a comprehensive analysis and determination for the polarization performance and transmission characteristics of light in various uniaxial birefringent components, and especially it is simple and clear in physical picture. © 2010 Elsevier B.V. All rights reserved.
Li J.,Xian Jiaotong University |
Zhu J.,Xian Jiaotong University |
Wu H.,Huayin Ordnance Test Center
Optics Letters | Year: 2010
The theoretical operation and experimental demonstration of a Fourier transform imaging spectropolarimeter for real time measurement of the polarization state of light are presented. The spectropolarimeter uses a Wollaston prismas a birefringent interferometer and two high-order retarders to incorporate channeled polarimetry. Compared with previous instruments, the most significant advantage of the described model is that the complete wavelength-dependent polarization is acquired simultaneously along a one-dimensional spatial image by a single snapshot. Also, we show that, in this configuration, we can benefit from the advantages of the model: it is compact and robust, and the birefringent interferometer has a high throughput. © 2010 Optical Society of America.
Gao M.,Shijiazhuang Mechanical Engineering College |
Zhang H.,Huayin Ordnance Test Center |
Zhou Y.,66393 Postdoctoral Science and Research Station |
Zhang B.,State Grid Corporation of China
Journal of Electronic Imaging | Year: 2016
In an effort to improve the tracking accuracy of the ground maneuvering target in infrared images, a method is proposed based on the strong tracking filter (STF) and the cubature Kalman filter (CKF) algorithms. In this method, the fading factor is introduced from the STF algorithm and is calculated by transforming the nonlinear measurement variance matrix to be linear approximately, and then the fading factor is used to correct the prediction error covariance matrix (PECM) of CKF, so that the gain matrix can be adjusted at real time and hence the tracking ability of the maneuvering target could be improved. After the digital simulation experiment, it is shown that, comparing with CKF and the unscented Kalman filter algorithms, the average tracking accuracy of the location is increased by more than 20% with the target velocity under 20 m/s and acceleration under 5 m/s2, and it can even be increased by 50% when the target step maneuver occurs. With the tracking experiment on the real infrared tank images, it can be concluded that the target could be tracked stably by the proposed method, and the maximum tracking error is not more than 8 pixels even though the 180 deg turning takes place. © 2016 SPIE and IS&T.