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The upraise of autonomous driving technologies asks for maps characterized bya broad range of features and quality parameters, in contrast to traditional navigation maps which in most cases are enriched graph-based models. This paper tackles several uncertainties within the domain of HD Maps. The authors give an overview about the current state in extracting road features from aerial imagery for creating HD maps, before shifting the focus of the paper towards remote sensing technology. Possible data sources and their relevant parameters are listed. A random forest classifier is used, showing how these data can deliver HD Maps on a country-scale, meeting specific quality parameters.

ABSTRACT:The federal governments of Germany endeavour to create a harmonized 3D building data set based on a common application schema (the AdV-CityGML-Profile). The Bavarian Agency for Digitisation, High-Speed Internet and Surveying has launched a statewide 3D Building Model with standardized roof shapes for all 8.1 million buildings in Bavaria. For the acquisition of the 3D Building Model LiDAR-data or data from Image Matching are used as basis in addition with the building ground plans of the official cadastral map. The data management of the 3D Building Model is carried out by a central database with the usage of a nationwide standardized CityGML-Profile of the AdV. The update of the 3D Building Model for new buildings is done by terrestrial building measurements within the maintenance process of the cadaster and from image matching. In a joint research project, the Bavarian State Agency for Surveying and Geoinformation and the TUM, Chair of Geoinformatics, transformed an AdV-CityGML-Profilebased test data set of Bavarian LoD2 building models into an INSPIRE-compliant schema. For the purpose of a transformation of such kind, the AdV provides a data specification, a test plan for 3D Building Models and a mapping table. The research project examined whether the transformation rules defined in the mapping table, were unambiguous and sufficient for implementing a transformation of LoD2 data based on the AdV-CityGML-Profile into the INSPIRE schema. The proof of concept was carried out by transforming production data of the Bavarian 3D Building Model in LoD2 into the INSPIRE BU schema. In order to assure the quality of the data to be transformed, the test specifications according to the test plan for 3D Building Models of the AdV were carried out. The AdV mapping table was checked for completeness and correctness and amendments were made accordingly.

ABSTRACT:The Bavarian State Office for Surveying and Geoinformation has launched a statewide 3D Building Model with standardized roof shapes without textures for all 8.1 million buildings in Bavaria. For acquisition of the 3D Building Model LiDAR-data are used as data basis as well as the building ground plans of the official cadastral map and a list of standardized roof shapes. The data management of the 3D Building Model is carried out by a central database with the usage of a nationwide standardized data model and the data exchange interface CityGML. On the one hand the update of the 3D Building Model for new buildings is done by terrestrial building measurements within the maintenance process of the cadastre. On the other hand the roofs of buildings which were built after the LiDAR flight and which were not measured terrestrially yet, are captured by means of picture-based digital surface-models derived from image-matching of oriented aerial photographs (DSM from image matching).* Corresponding author. 1.1. 1. INTRODUCTIONDue to the federal structure in Germany the official surveying and mapping is assigned to the states. Therefore, nationwide projects need close cooperation and commitment by the states. »The Cadastral and Surveying Authorities of the state, which are responsible for the real estate cadastre and state survey (Official German Surveying and Mapping), cooperate within the Working Committee (AdV, URL: http://www.adv-online.de) of the Surveying Authorities of the States of the Federal Republic of Germany to discuss technical issues of fundamental and nationwide importance targeting standardized regulations.« This includes the determination of common standards for the acquisition of 3D Building Models across Germany. In 2012 AdV decided a product standard for 3D Building Models. According to that, the building ground plans are derived from the official digital cadastral map and the buildings are represented as blocks uniformly with a flat roof in the so called first detailed level (Level of Detail 1 -LoD1). Since 2013 a central LoD1-dataset is initially assembled which is expected to be centrally delivered in the middle of 2013. The data exchange between the states and the central service center uses a nationwide uniform profile of the AdV based on the City Geography Markup Language (CityGML) Encoding Standards from OpenGIS ® and the Open Geospatial Consortium (OGC) Specification CityGML 1.0.0. This AdV-CityGML-profile is also designed for the delivery of building data with standardized roof shapes as building models of the second detailed level (LoD2) with optional photorealistic textures. The degree of automatic recognition of roof shapes and the elevation accuracy of the automatic roof reconstruction are on the one hand dependent on the degree of generalization of the roofs to the standard roof forms and on the other hand based on the acquisition basis. If LiDAR-data (Light Detection And Ranging) from airborne laser scanning is used for the acquisition, then the density of the point cloud is si...

In the Bavarian Surveying Administration, remote sensing methods are applied in the context of nationwide airborne surveys for the acquisition of aerial photographs and airborne laser scanning for the derivation of the digital terrain model (DTM). At the Bavarian Agency for Digitisation, High-Speed Internet and Surveying (LDBV = Landesamt für Digitalisierung, Breitband und Vermessung), image-based digital surface models (bDOM) and digital orthophotos without building lean (trueDOP) are produced using the dense image matching (DIM) method. Buildings and their roofs are displayed in the trueDOP in the correct position to the cadastral ground plan. Based on these data, an expert system was developed for the investigation of construction cases and for the updating of 3D building models, which automatically calculates change notices and makes them available to the Agencies for Digitisation, High-Speed Internet and Surveying (ADBV = Amt für Digitalisierung, Breitband und Vermessung). The reliable detection of buildings plays a decisive role here. Representative reference classes for the classification of building roofs in the RGB colour space are formed and frequencies are calculated across the boundaries of the photo-flights. The classification is carried out with the aid of a normalized digital surface model (nDOM), which is calculated from the height differences between the bDOM and the DTM, and with heuristically defined threshold values for the colours in the representative RGB colour spaces. The presented method is transferable to all federal states.