Explore chapters and articles related to this topic
Phase congruency-based filtering approach combined with a convolutional network for lung CT image analysis
Published in The Imaging Science Journal, 2021
Mohamed Ben Gharsallah, Hassene Seddik
Image filters can be categorized into three principal classes (Figure 2): spatial, transform domain and hybrid filtering. Spatial filtering uses conventional techniques of image filtering, which works directly on the pixels of images. Though categorized as classical does not mean the filtering methods on spatial domain finishes to be recommended. Principally, this filtering technique may be classified into two classes, linear and non-linear filters. Transform domain filter methods based on low pass frequency filtering have been proposed to reduce the additive noise that taints a digital image. These filtering techniques reduce noise very well in homogeneous areas of the image but also have the major disadvantage of also strongly attenuating the high frequencies of the image as contours, details and texture of the image.