Development of the system for automatic map generalization based on constraints

Transcription

1 Development of the system for automatic map generalization based on constraints 3rd Croatian NSDI and INSPIRE Day and 7th Conference Cartography and Geoinformation Marijan Grgić, mag. ing. Prof. dr. sc. Nada Vučetić, Geodetski fakultet, Zagreb Dragan Divjak, dipl. ing., Geofoto d.o.o. Split, 2011

2 Content Automated cartographic generalization Multi-agent systems in cartography Developed system for automatic map generalization

3 Automated generalization The development of conceptual models of cartographic generalization The development of algorithms to perform transformations in the generalization The development of information technology and multi-agent systems

4 Automated generalization the creation of cartographic representations in different scales from the same spatial database reducing the impact of cartographers in creating cartographic products (standardization)

5 Automated generalization Why generalization is hard to automate? the process of design is complex, different phenomena at different levels of detail (different scale) should be easy to explore, seeing generalization as a something you do at the end, interaction during map generalization is not standardized.

6 Multi agent systems (MAS) a system composed of multiple interacting intelligent agents, in the field of artificial intelligence, an agent - autonomous entity that within a system monitors the other elements of the system and directs its activities to achieving predefined goals, decentralization autonomy agent local views

7 Map generalization based on constraints Key aspects of constraints: A constraint can be specified as something to maintain or something to avoid, Aconstraintcanbeabsolute, something to optimize or both, A constraint has an application scope or extent, Aconstraintcanbeintrinsic or extrinsic, Aconstraintcanbeindependent or contextual, Constraints may operate differently at different scales of spatial analysis, Violations of constraints can be detected and evaluated by analyzing micro-, meso- and macroscale data using one or more measures.

8 Map generalization based on constraints AGENT project (Automated GEneralisation and New Technology) 1 A B 2 3 B D C 4 5 A hypothetical network of constraints in a generalization process

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12 Task: Topology of map objects must be maintained, roads must maintain its spatial position, roads may be generalized using algorithms for generalization, buildings depending on their surface should be displayed or omitted from the map view, system should assign a cartographic sign to a building if it meets the minimum area request, buildings should be set at a constant distance from roads, buildings should be set parallel to the direction of roads which are nearest to them, roads should not cross buildings, cartographic signs should not be overlap in the map view.

13 Safe Software FME Desktop primarily intended for conversion, transformation, and modifying the spatial raster and vector data FME Workbench, FME Universal Viewer, FME Universal Translator, FME Command-Line Engine interoperability, centralization and retaining attribute data

14 Smoothing using McMaster s algorithm

15 Minor and major roads - a problem in connecting

16 Minor and major roads - a problem in connecting

17 Original data

18 Buildings represented by cartographic signs

19 Buffered roads

20 Buildings represented by points set on a constant distance from roads

21 Buildings represented by cartographic signs set on a constant distance from roads

22 Buildings set parallel to the direction of roads

23 Buildings crossed by roads

24 Buildings crossed by roads

25 Problem with overlapping

26 Problem with overlapping

27 Vlastiti sustav za automatsku generalizaciju

28 Vlastiti sustav za automatsku generalizaciju

29 Vlastiti sustav za automatsku generalizaciju

30 Vlastiti sustav za automatsku generalizaciju

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37 MAS systems and map generalization Advantages: efficiency and effectiveness, robustness and reliability, flexibility and adaptability of the system, reduced costs (in the long run), opportunities for development and reusability of the system. Shortcomings: problem of the assessment of the quality of the final product, large initial investment, some procedures can not be automated at this moment.

38 MAS systems and map generalization Future directions: developing of new and better algorithms for generalization, facilitating quality assessment, post-editing, and representation refinement, creating an adaptive standardized system that automatically derives scale-based settings for generalization operators, parameters, priorities, and other preferences that govern the generalization processes and decisions, integration of more powerful algorithms in commercial software, creating of Web services for generalization and standalone applications for the generalization.

39 MAS systems and map generalization Conclusion: many NMAs and commercial map publishers need generalization in order to derive multiple products from a master database, map generalization using MAS systems and generalization systems has many advantages compared to traditional methods, MAS systems will be able to almost completely replace the manual generalization in the future.

40 Thank you for your attention.