We propose a novel framework for the analysis and modeling of discrete edge filters, based on the notion of signed rays. This framework will allow us to easily deduce the geometric and localization properties of a family of firstorder filters, and use this information to design custom filter banks for specific applications. As an example, a set of angle-selective corner detectors is constructed...

Many information of an object can simultaneously be conserved by histogram based features. Because of the different intensities of pixels and different lighting conditions in an image, histograms which are employed for extracting features are better to be first equalized. In this paper, the effect of equalization over the histograms used for feature extraction is studied. Experimental results o...

ÐIn edge and corner detection applications, it is typical to examine a single scale without knowing which scale is appropriate for each location in the image. However, many images contain a wide variation in the distance to the scene pixels and, thus, features of the same size can appear at greatly differing scales in the image. We present a method where the scale of the filtering and feature d...

Recently, a lot of research has been done on the matching of images and their structures. Although the approaches are very different, most methods use some kind of point selection from which descriptors or a hierarchy are derived. We focus here on the methods that are related to the detection of points and regions that can be detected in an affine invariant way. Most of the previous research co...

In intelligent surveillance of construction sites, safety helmet detection is great significance. However, due to the small size helmets and presence high levels noise in scenarios, existing methods often encounter issues related insufficient accuracy robustness. To address this challenge, paper introduces a new algorithm, FEFD-YOLOV5. The FEFD-YOLOV5 algorithm enhances performance by adding sh...