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Utilization of ALS data for update of a road network
Kutišová, Tereza ; Lysák, Jakub (advisor) ; Brůha, Lukáš (referee)
Utilization of ALS data for update of a road network Abstract My thesis concerned problematics of automatic detection of communication data from aerial laser scanning. Goal of this method is to identify area of roads - tarmacs as accurate as possible. On its basis are counted attributes of specific parts. In first part of the thesis are summarized known procedures, which are used to deal with the issue and experiences and evaluation of the output of theirs authors. In practical part of the thesis is described procedure methodology, which is based on findings from the literature review. Subsequently, input data and model areas are introduced. In the final parts are described results and compared with the results of authors, who used such evaluation in their work. Key words: airborne laser scanning, digital topographic database, road network, database update
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Classification of Airborne Laser Scanning Data in Sandstone Landscapes
Tomková, Michaela ; Lysák, Jakub (advisor) ; Potůčková, Markéta (referee)
Classification of Airborne Laser Scanning Data in Sandstone Landscapes Abstract This work is concerned with the classification of airborne laser scanning data in sandstone landscapes called "rock cities". Standard filters do not work reliably in such a rugged terrain covered with dense vegetation and in the results the rock formations are smoothed or even removed from the terrain. The method of classification suggested in this work is based on the procedure used in manual filtration. When exploring a sufficiently dense point cloud in 3D, one is able to distinguish rock formations from trees even though their shapes are similar. In contrast to trees, rock pillars are modeled only by points reflected off the surface and therefore they make concave elevations in the ground. Because of penetration of trees, there are points reflected off a treetop, branches, leaves and also ground under the tree. The proposed method segments a point cloud according to local minima in approximated surface and classifies these objects into classes rock, tree, and mix by inner point distribution. Objects in classes tree and mix are then filtered by lasground function from LAStools. The method was tested with merged point cloud consisted of data from the standard airborne laser scanning of the Czech Republic and experimental...
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Production of cartographically correct countour lines from airborne laserscanning data in flat terrain
Picek, Jan ; Lysák, Jakub (advisor) ; Bayer, Tomáš (referee)
Production of cartographically correct countour lines from airborne laserscanning data in flat terrain Abstract The thesis is dedicated to the creation of contour lines from the data of airborne laserscanning in flat areas. For creation of contour lines in these parts is necessary specific generalization, that smooths unwanted artifacts, but does not delete the shapes, which are characteristic for the relief. The first part of the thesis is to serve as a short insight into the areas on which it is built, this thesis: the principle of airborne laserscanning and basic information on the contour line model. On the basis of technical literature are defined the requirements for the correct representation of the contour and cartographicly presented the different types of the DEM and generalization of contours. The main aim of this work is to design an algorithm that will combine several methods of generalization of contour while maintaining altitude accuracy as well as other requirements on their cartographicly the right terms, and to test this approach in several territories. In conclusion, the results of the methods of work and its implementation critically evaluated and outlined other possible developments of this issue. Keywords hypsography, airborne laserscanning, digital cartography, contour lines,...
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Characterisation of waterfalls in Krkonoše (Czechia) with the use of airborne laserscanning data
Hájek, Robert ; Lysák, Jakub (advisor) ; Janata, Přemysl (referee)
Characterisation of waterfalls in Krkonoše (Czechia) with the use of airborne laser scanning data Abstract This thesis deals with the possible use of airborne laser scanning data for the characterisation of waterfalls in Krkonoše Mountains. Data, which are used, was provided by The Krkonoše mountains national park administration. The objective of the thesis is a description of a new method how to locate the waterfall, measure its height, calculate basin area and create a longitudinal profile. The main research method is the analysis of the digital terrain model, derived from ALS data. The analysis is based on the use of ArcGIS 10.4.1 hydrological tools to detect the position of watercourses and to find optimal visualizations for locating crests and bases of the waterfalls. The characteristics of 28 selected waterfalls were obtained by using the proposed method. The end of the work presents the results and there are also discussed imperfections that were detected during application of the method. Keywords: airborne laser scanning, waterfall, Krkonoše
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Calculation of forest stand heights on the basis of airborne laser scanning on the territory of Training Forest Enterprise Křtiny
Procházková, Andrea
This diploma thesis deals with calculation of forest stand heights on the basis of airborne laser scanning (ALS) on the territory of Training Forest Enterprise Křtiny. Point cloud data from ALS were interpolated into digital terrain model (DTM), digital surface model (DSM) and subsequently by subtraction of DTM from DSM into canopy height model (CHM). Inverted CHM was used for detection of tree tops by Inversed Watershed Segmentation; tree tops were identified as local minima. Calculated heights of forest stands were compared with height data taken from Forest Management Plan (FMP) and with data from field survey.
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Utilization of additional information on the pulse for ALS data classification in rugged terrain
Poláková, Tereza ; Lysák, Jakub (advisor) ; Potůčková, Markéta (referee)
Utilization of additional information of the pulse for ALS data classification in ragged terrain Abstract The diploma thesis deals with airborne laser scanning filtering problem in sandstone landscape which is characterized by ragged terrain and in our country also by dense vegetation that makes difficult to transit laser pulse to terrain that can lead to lower accuracy of created DTM. In the first part the basic filtering algorithm that are systematic divided into several groups are described. The emphasis is also put on theoretic problems which we have to deal with during the filtering of laser scanner data acquired in sandstone landscape. The main goal of the thesis is to suggest changes in one of the existing algorithm to additional information of the pulse (mainly amplitude and width of the pulse) be used, and to test this method over the real data. At the end the results of the method and its implementation are critically evaluated. Keywords: airborne laser scanning, point cloud segmentation, point cloud classification, sandstone landscape, DTM
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Topographic mapping of rock formations with the use of airborne laser scanning data
Lysák, Jakub ; Potůčková, Markéta (advisor) ; Brázdil, Karel (referee) ; Šíma, Jiří (referee)
Abstract This thesis focuses on topographic mapping of rock formations with the use of new technologies in a comprehensive manner, from airborne laser scanning (ALS) data acquisition and processing in rocky terrains, followed by their processing to the content of topographic databases and their cartographic processing in maps. The introduction discusses issues of importance for practice, and the relation between topographic mapping of rocks and other fields of human activity. The ALS section describes products for topographic mapping of rocks derived from ALS data, and discusses the specifics of ALS data acquisition and processing in wooded rugged terrain. Existing solutions of this problem are explained and their limitations are identified. Author's own approaches to solving this task are presented as case studies, including three made a further three designed experiments with ALS data processing and evaluation of their results. Recommendation regarding mapping of sandstone landscapes in Czechia have been also addressed. The topographic section describes the current representation of rocks and related objects in the ZABAGED database (Czech national digital topographic database), explains the historical context, analyzes this data and identifies their shortcomings in relation to the ALS. Research...
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Utilization of airborne laser scanning data for the detection of agrarian forms of relief in the Giant Mountains
Jebavá, Lucie ; Kupková, Lucie (advisor) ; Potůčková, Markéta (referee)
Utilization of airborne laser scanning data for the detection of agrarian forms of relief in the Giant Mountains Abstract This thesis deals with the possible use of airborne laser scanning data for the detection of agrarian forms of relief in the Giant Mountains. The main research method is the analy- sis of the digital terrain model and digital surface model in the area of the Giant Mountains in the software ArcGIS 10.0. The analysis is based on specific functions in ArcGIS software (Slope, Curvature) as well as on combinations of rasters of shaded reliefs which led to the detection of further agrarian forms. To verify the precision of agrarian forms detection field verification was used. Based on verification and accuracy assessment the results can be designated as a very satisfactory. The Administration of the Giant Moun- tains National Park can use the research results to quantify the agrarian forms of relief, to improve their protection and, possibly also for further research and management. Keywords: airborne laser scanning, agrarian forms of relief, anthropogenic geo- morphology
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Modelling of selected forest geometric parameters from airborne laser scannig data
Sedláčková, Oldřiška ; Potůčková, Markéta (advisor) ; Klimánek, Martin (referee)
Modelling of selected forest geometric parameters from airborne laser scanning data Abstract The main aim of this work is to approximate the shape of a tree crown with mathematically describable 3D shape based on airborne laser scanning (ALS) data. And consequently derive geometrical parameters describing the tree from this model. Included in the work is a custom designed algorithm based on angular segmentation. Measured results of this algorithm are then compared to an algorithm based on RANSAC and field measurement. The first part of this work describes airborne laser scanning, its use to derive characteristics of forest stands and individual trees and the theory of tree crown modelling. The next part contains a description of both algorithms and presentation of results and field measurements. The conclusion summarizes and evaluates the outputs of the custom angular segmentation algorithm and discusses its possible modifications. Keywords: airborne laser scanning, tree height, crown width, crown height, crown cover, crown volume, crown shape, RANSAC
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Visualization of DTMs made from airborne laser scanning data
Picek, Jan ; Lysák, Jakub (advisor) ; Dušánek, Petr (referee)
Visualization of digital terrain models made from airborne laser scanning data Abstract The aim of this study is to evaluate opportunities of 2D visualization of digital terrain models made from airborne laser scanning data. Each method is described in detail with other parameters and approach. The focus is put on methods which are useful for the topographic mapping (f. e. orienteering maps) and for cartographic visualization. All this methods are tested for different data and type of relief (plain, mountainous, rock city, area with negative shapes). The aim of study is to find the optimal method for each type of relief which expresses most of typical features. There are shown methods on the maps for orienteering sports for detection of different object from airborne laser scanning data. Keywords: airborne laser scanning, digital terrain model, data visualization, hillshading
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