This paper is concerned with the robust identiication of patches from simple geometric surfaces such as planes, spheres, and cylinders. This is done from 3D data acquired using a range scanner, along with principal quadric estimates at each point. Properties of the Gaus-sian and mean curvature (e.g., their sign) at points on surfaces of the target class are used to reject all points that could ...

Full-waveform lidar system records the received signals continuously for analysis. As it provides more information than the conventional pulsed lidar, the waveform lidar plays an important role in land cover classification as well as object reconstruction. The objective of this research is to analyze the features of grouped full-waveform lidar point clouds. The two major works are segmentation ...

Cell segmentation from microscopic images is the first stage of the automatic biomedical image processing, which plays a crucial role in the study of cell behaviour which is a very difficult and tedious task because of the variation that exist in illumination and dye concentration of the cells due to the staining procedure. This paper proposes a new method for segmentation of cervical cell nucl...

This paper presents a new LiDAR segmentation technique for automatic extraction of building roofs. First, it uses a height threshold, based on the digital elevation model to divide the LiDAR point cloud into ‘ground’ and ‘non-ground’ points. Then starting from the maximum LiDAR height, and decreasing the height at each iteration, it looks for coplanar points to form planar roof segments. At eac...

Vessel cross-sectional diameter is an important feature for analyzing retinal vascular changes. In automated retinal image analysis, the measurement of vascular width is a complex process as most of the vessels are few pixels wide or suffering from lack of contrast. In this paper, we propose a new method to measure the retinal blood vessel diameter which can be used to detect arteriolar narrowi...

Massive events, as sportive events, involves a huge amount of spectators. Citizens that wish to attend buy a ticket that allows them to seat in a given zone of the stadium with several features, but usually they do not buy the physical seat at the sport ground. Then, one of the duties of the organizing committees is to allocate the different localities of the enclosure to the persons that have ...

This study has utilized a spatial region growing segmentation and a classification using fuzzy membership vectors to detect the changes in the images observed at different dates. Consider two co-registered images of the same scene, and one image is supposed to have the class map of the scene at the observation time. The method performs the unsupervised segmentation and the fuzzy classification ...

A new region growing algorithm has recently been proposed for computing Euclidean Distance Maps in a time comparable to widely used chamfer DT. In this paper we show how this algorithm can be extended to more complex tasks such as the computation of distance maps on an-isotropic grids and the generation of a new type of Euclidean skeletons.

Als annähernd unabhängige anatomische Komponenten der Lunge spielen die Lungenlappen eine wesentliche Rolle bei der Diagnose und Therapie von Lungenkrankheiten. Leider stellt eine genaue Lokalisierung der Lappengrenzen, der sogenannten Fissuren, sogar für Experten oftmals eine nicht-triviale Aufgabe dar. Das liegt unter anderem daran, dass die Fissuren aus sehr dünnem Bindegewebe bestehen. Beso...

The detection of scars in the cerebral cortex usually involves a manual process performed by radiologists, who have to face multiple troubles. For example, the bad calibration of the equipment used to get images of the cerebral cortex can cause spacial and geometrical distortions in the MRI (Magnetic Resonance Imaging) sequences. Owing to the advances in algorithms capable of analyzing MRI sequ...