Airborne laser scanning provides a huge amount of data in the form of point cloud located in space. A full-waveform laser scanners generate informations such as amplitude, backscatter cross section and echo width. The latter is the main subject of the thesis. Automatic and simple classification of laser points is still a major challenge, especially in specific tasks such as buildings modelling. Many procedures for buildings modelling are still very dependent on human judgement. This problem encourages us to analyse echo width as a possibility for the extraction of the buildings outline. Practical work presented in the thesis was accomplished in Vienna, at the Institute of Photogrametry and Remote Sensing. All required data, professional help and all final results were gained during my research at this Institution. Analysis includes two parts: the first one presents a research on the echo width and the selection of the points adequate for further process, the second one process of segmentation. A slope adaptive neighbourhood system was used and the segments acquired which represent buildings outlines of two selected houses. Main motivation for the work was a quest for more simple and automatic procedures; yet, this analysis is still based on personal judgement and not automatic work. Nevertheless, the main goal has been achieved: the extraction of the buildings outline. The thesis presents and describes an echo width in great detail. At the end a comparison between laser data results and cadastral data is also presented. A comparison of both is included as an interesting detail but is not relevant for evaluating of the data.
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