本文主要研究了频域滤波中平滑以及锐化技术，借助Butterworth滤波器以及Gauss滤波器探究了低通滤波器的性质；结合USM技术，Laplacian算子、以及Butterworth/Gauss滤波器研究了高通滤波器的特性.

doc文档最后附有所有我编写的的matlab代码-This paper studies the frequency domain filtering smoothing and sharpening techniques, using Gauss filter Butterworth filter and explores the nature of the low-pass filter　combined USM technology, Laplacian operator, and Butterworth/Gauss filter to study the high-pass filter characteristics. doc document with all my final written matlab code