Defocus Blurred Restoration Method for Raindrops Imaging and Its Application

Journal of Atmospheric and Environmental Optics ›› 2018, Vol. 13 ›› Issue (4): 315-320.

Defocus Blurred Restoration Method for Raindrops Imaging and Its Application

LIU Xichuan, HU Yuntao, GAO Taichang, Song Kun

(College of Meteorology and Oceanography, National University of Defense Technology, Nanjing 211101, China)

Received:2017-03-15 Revised:2017-05-11 Online:2018-07-28 Published:2018-07-10
Contact: 刘西川（1985-），男，河北清河人，博士，讲师，主要从事光学大气探测技术方面的研究。 E-mail: liuxc2012@hotmail.com
About author:刘西川（1985-），男，河北清河人，博士，讲师，主要从事光学大气探测技术方面的研究。
Supported by:
Supported by National Natural Science Foundation of China （国家自然科学基金, 41327003, 41505135）, Natural Science Foundation of Jiangsu Province（江苏省自然科学基金，BK20150708）

Abstract

Abstract:

Aiming at the raindrops imaging degradation of precipitation micro-physical characteristics sensor (PMCS), and consider the defocus blurring due to light source, a raindrop images restoration method based on point spread function (PSF) is proposed. Sharp images of raindrops can be obtained by the disk function. The radius of defocus blurring and thresholds of images binarization are determined by the calibration experiment of a series of glass balls, which have similar optical features with raindrops. The field experiment results show that the images restoration method can precisely correct the raindrops size and their distribution, the raindrop size distribution and rainrate measured by PMCS are in good agreement with the measurements of laser disdrometer. The application of images restoration method can promote the performance of raindrop size distribution, and other micro-physical characteristics measured by PMCS.

Key words: raindrops, images, point spread function, raindrop size distribution

CLC Number:

P412.13

LIU Xi-Chuan, HU Yun-Tao, GAO Tai-Chang, SONG Kun. Defocus Blurred Restoration Method for Raindrops Imaging and Its Application[J]. Journal of Atmospheric and Environmental Optics, 2018, 13(4): 315-320.

References

[1]Gao Taichang. Current and prospective development of the precipitation measuring techniques [J]. Meteorological and Hydrological Equipments, 2012, 23(6): 1-7(in Chinese).
高太长. 降水测量技术现状与展望 [J]. 气象水文装备, 2012, 23(6): 1-7.
[2] Yang Yanrong, Zeng Mingjian. Numerical simulation analysis on radar data assimilation for summer rainstorm forecast [J]. Journal of the Meteorological Sciences, 2012, 32(2): 145-152(in Chinese).
杨艳蓉, 曾明剑. 雷达资料同化对暴雨预报影响的数值模拟研究 [J]. 气象科学, 2012, 32(2): 145-152.
[3] Pu Jiangping, Zhang Hao, Zhou Xiao, et al. Comparative analysis on rain spectrum characteristics of deep convective cloud and its radar reflectivity [J]. Journal of the Meteorological Sciences, 2012, 32(3): 253-259(in Chinese).
濮江平, 张昊, 周晓, 等. 对流性降水雨滴谱特征及其与雷达反射率因子的对比分析 [J]. 气象科学, 2012, 32(3): 253-259.
[4] Jones D M A. The shape of raindrops [J]. Journal of Meteorology, 1959, 16: 504-510.
[5] Yu Dongsheng, Xu Qingshan, Xu Chidong, et al. Progress of measurement of raindrop size distribution [J]. Jounal of Atmospheric and Environmental Optics, 2011, 6(6): 403-408(in Chinese).
余东升, 徐青山, 徐赤东, 等. 雨滴谱测量技术研究进展 [J]. 大气与环境光学学报, 2011, 6(6): 403-408.
[6] An Yingyu, Jin Fengling, Zhang Yunfeng, et al. Automatic indentification methods of ground raindrop spectrum observation and image [J]. Journal of Applied Meteorological Science, 2008, 19(2): 188-193(in Chinese).
安英玉, 金凤岭, 张云峰, 等. 地面雨滴谱观测的图像自动识别方法 [J]. 应用气象学报, 2008, 19(2): 188-193.
[7] Gao Taichang, Liu Xichuan, Liu Lei, et al. Current and prospective development of the precipitation measuring scientific instruments [J]. Chinese Journal of Scientific Instrument, 2012, 33(8): 255-260(in Chinese).
高太长, 刘西川, 刘磊, 等. 降水测量科学仪器现状及展望 [J]. 仪器仪表学报, 2012, 33(8): 255-260.
[8] Joss J, Waldvogel A. A raindrop spectrograph with automatic analysis [J]. Pure and Applied Geophysics, 1967, 68: 240-246.
[9] Loffler-Mang M, Joss J. An optical disdrometer for measuring size and velocity of hydrometers [J]. Journal of Atmospheric and Oceanic Technol., 2000, 17(2): 130-139.
[10] Randeu W L, Kozu T, Shimomai T, et al. Raindrop axis ratios, fall velocities and size distribution over Sumatra from 2D-Video Disdrometer measurement [J]. Atmospheric Research, 2013, 119: 23-37.
[11] Battaglia A, Rustemeier E, Tokay A, et al. PARSIVEL snow observations: A critical assessment [J]. Journal of Atmospheric and Oceanic Technology, 2010, 27(2): 333-344.
[12] Szakall M, Diehl K, Mitra S K, et al. A wind tunnel study on the shape, oscillation, and internal circulation of large raindrops with sizes between 2.5 and 7.5 mm [J]. Journal of Atmospheric Sciences, 2009, 66(3): 755-765.
[13] Wang Mei, Pan Guohua, Wang Guohong, et al. The restoration method of motion-blurred and defocus-blurred images and its application [J]. Laser and Infrared , 2007, 37(10): 1120-1123(in Chinese).
王枚, 潘国华, 王国宏, 等. 运动和散焦模糊图像的复原方法及其应用研究 [J]. 激光与红外, 2007, 37(10): 1120-1123.
[14] Yang Lihong, Zhao Bianhong, Zhang Xingxiang, et al. Gaussian fitted estimation of point spread function and remote sensing image restoration [J]. Chinese Optics, 2012, 5(2): 181-188(in Chinese).
杨利红, 赵变红, 张星祥, 等. 点扩散函数高斯拟合估计与遥感图像恢复 [J]. 中国光学, 2012, 5(2): 181-188.
[15] Shu Xiaojian, Gao Taichang, Liu Xichuan, et al. Observation and analysis of raindrop shape based on the precipitation micro-physical characteristics sensor [J]. Meteorological Monthly, 2017, 43(1): 91-100(in Chinese).
舒小健, 高太长, 刘西川, 等. 基于降水微物理特征测量仪的雨滴形状观测与分析 [J]. 气象, 2017, 43(1): 91-100.