运用窗函数提高运动模糊图像PSF参数精度的方法  

Method to Improve Accuracy of PSF parameters of Motion Blur Images using Window Functions

作　　者：琚三元 高树辉[1] Ju Sanyuan;Gao Shuhui(School of Investigation,People’s Public Security University of China,Beijing 100038,China)

机构地区：[1]中国人民公安大学侦查学院,北京100038

出　　处：《激光与光电子学进展》2024年第4期541-548,共8页Laser & Optoelectronics Progress

基　　金：中国人民公安大学刑事科学技术双一流创新研究专项(2023SYL06)。

摘　　要：运动模糊图像点扩散函数(PSF)的精确估算是模糊图像复原的关键。为了提高PSF参数估计的准确性,消除频谱图中央亮线对模糊角度估计的干扰,提出一种运用窗函数来提高PSF参数估计精度的方法。对运动模糊图像进行二维离散傅里叶变换和对数运算,计算图像的功率频谱图,对频谱图像添加窗函数Hanning,对处理后的图像进行中值滤波平滑处理和二值变换处理,再结合形态学算法和Canny算子边缘检测对频谱图进行优化,最后通过Radon变换,得到模糊方向。根据模糊方向结果,在模糊角度方向上对运动模糊图像的频谱图进行Radon变换,分析负峰值之间的距离,得到暗条纹间距,根据暗条纹间距与模糊长度之间的关系,求出模糊长度,从而完成两个点扩散函数参数的估算。结果显示,与现有算法相比,所提算法提高了参数估计的精度,复原时产生的振铃和伪影现象减少,充分利用图像信息的同时操作简便。Accurate estimation of the point spread function(PSF)is crucial for restoring blurry images caused by motion blur.This paper proposes a method using window functions to improve the accuracy of PSF parameter estimation and eliminate the interference from the central bright line in the spectrogram on the blurred-angle estimation.To achieve this,two-dimensional discrete Fourier transform and logarithmic operation are performed on the motion-blurred image,followed by the calculation of the power spectrogram.Thereafter,the Hanning window function is added to the spectrogram,and the image is processed using median filtering smoothing and binary transformation processing,in combination with morphological algorithm and Canny operator edge detection.Finally,the fuzzy direction is obtained using the Radon transform.Based on the blurred-direction results,the spectrogram of the motion-blurred image is processed by Radon transform in the direction of the blur angle.The distance between the negative peaks is analyzed to obtain the dark fringe spacing,and the blur length is calculated according to the relation between the dark fringe spacing and the blur length.This completes the estimation of the two point spread function parameters.Comparing the proposed algorithm with existing ones,the results show an improvement in the accuracy of parameter estimation,and a reduction in ringing and artifact phenomena generated during restoration.The proposed method makes full use of image information,and is easy to operate.

关 键 词：窗函数 运动模糊图像 图像复原 点扩散函数 参数估计 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]