Karim M A, Liu H K
Department of Electrical Engineering, The University of Alabama, PO Box 6169, University, Alabama 35486, USA.
Opt Lett. 1981 May 1;6(5):207-9. doi: 10.1364/ol.6.000207.
Linear and logarithmic coherent spatial-filtering techniques are compared in the separation of multiplicative noise from an image in a coherent-optical image-processing system. It is demonstrated that both techniques are effective in the removal of simple grating-type high-frequency noises, but that linear filtering cannot remove noise of spatial frequencies lower than 5 lines/cm, whereas logarithmic filtering can.
在相干光学图像处理系统中，对线性和对数相干空间滤波技术在从图像中分离乘性噪声方面进行了比较。结果表明，两种技术在去除简单光栅型高频噪声方面都是有效的，但线性滤波无法去除空间频率低于5线/厘米的噪声，而对数滤波则可以。
