太阳X-EUV成像望远镜的图像优化处理

太阳X-EUV成像望远镜主要用来监测和预报影响空间天气变化的太阳活动,成像资料专门服务于空间天气预报研究.为了满足望远镜的空间适应性,望远镜获取的图像会受到其结构调制形成的噪声干扰.本文主要对望远镜所获取的图像进行优化处理,讨论了傅里叶变换的物理意义及其在图像处理中的应用.通过二维离散傅里叶变换,将图像变换到频率域空间;选用巴特沃思陷波滤波器滤波,通过程序设计,实际调试,在尽量减少图像失真的前提下,滤除图像中的周期性噪声.优化后的图像有利于进一步分析太阳活动现象.

Optimizing Process of the Images Captured by the Solar X-EUV Imaging Telescope

The solar X-EUV imaging telescope is mainly used to monitor and predict the solar activities that affect the space weather.The observed materials will be dedicated to the space weather forecast.For the space adaptability of the telescope,the image captured by CCD will be affected by the noise formed in structure modulation.This essay focuses on the optimizing process of the images captured by the telescope.It discusses the physical meaning of Fourier transform and its application in the image processing.With two-dimensional discrete Fourier Transform,images are transformed into frequency domain.With Butterworth wave-isolation filter,the program was designed and adjusted in practice,thus the periodicity noise in the image is smoothed to reduce the distortion of images as less as possible.The optimized images are favorable for further analysis of the solar activities.