1. Key Laboratory of Spectral Imaging Technology, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an 710119, China
2. University of Chinese Academy of Sciences, Beijing 100049, China
Abstract:Air pollution has a serious effect on the quality of image, and image taking under hazy weather suffers from poor contrast and resolution. It is of great significance to use the polarimetric spectral information for image dehazing and the research of polarization dehazing for spectral data cube. The data used in this paper was pushbroomed under moderate hazy weather, and original Vis-NIR polarimetric data of 380~1 000 nm was captured, the original polarimetric images at 450, 550, 650, 750, 850 nm and the dehazed images were studied. The results of the research showed that wavelength had a significant effect on the difference of gray value between targets and background, and both the dynamic range of gray value and the smoothness of histogram were improved after the dehazing process. On average, the image contrast of the far-field targets increased by 5 times. The far-field targets at 450 nm had the lowest contrast, and the dehazing process increased the image contrast by 7.13 times which made the undetectable targets detectable. The far-field targets at 850 nm had the highest contrast, and the dehazing process increased the image contrast by 3.86 times. The dynamic range of histogram of the full image increased to 13.5% to 28.6% from 450 to 850 nm, the dynamic range of histogram of the near-field targets are increased to 33.3% to 44.0%. Based on the analyzation of the possible estimation error, two correction factors were proposed to revise the degree of polarization of the airlight and the intensity of the airlight from an object at an infinite distance, the regularity of the two factors were given to guide the image dehazing process under new conditions. The polarimetric information is obtained through the original data by the Stokes parameters, the dehazing process is based on the polarimetric difference between the air light scattered from the haze particles and the direct light reflected from the objects. The polarization spectral dehazing technique not only expands the application area of the imaging spectrometer, but also provides a new idea for image dehazing.
夏 璞,刘学斌. 偏振光谱图像去雾技术研究[J]. 光谱学与光谱分析, 2017, 37(08): 2331-2338.
XIA Pu, LIU Xue-bin. Study on the Polarization Spectral Image Dehazing. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2017, 37(08): 2331-2338.
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