DIGITAL SYSTEMS FOR AUTOMATED CARTOGRAPHIC FEATURE EXTRACTION

Working Group II/1 ABSTRACT Major research and development efforts are put on the automated extraction of man-made structures, like roads and buildings from digital aerial and space imagery. The approaches range from manual methods, to semi-automated and automated feature extraction methods from single and multiple image frames and digital surface models. The comparison of systems in literature is quite difficult. The used object model is not always explicitly defined. Quite often the amount of parameters and thresholds to be set by an operator are not given and there is still no comprehensive comparison performed to existing methods. Most efforts are put on building extraction. Considerably less on road networks and few on vegetation and river networks. Several systems are commercially available or close to it. They are using semi-automatic or automatic components with pre- and post editing. There is a definite trend to use existing map or GIS (Geographic information system) data for the extraction process. Lately more information has become available on the performance of single automated components. The field is quite young, and the major approaches are not settled. We can be, however, optimistic, that there will be more systems on the market dealing with automated feature extraction. They are not only provided by the classical vendors and we will for sure see some on the ISPRS Congress in Amsterdam. We will also see a trend to desktop and web-top photogrammetry reflected by the congress themes 'geoinformation for alland 'geoinformation producible by all'.