Multidimensional Data Modeling for Feature Extraction and Mapping

1. Multidimensional Data Modeling for Feature Extraction and Mapping E. Lynn Usery usery@usgs.gov ACSM April 19, 2004 http://mcmcweb.er.usgs.gov/carto_research

2. Outline • Motivation • Objectives • Approach • Theoretical Model • Implementation • Scale Dependent Feature Rendering • Conclusions

3. Motivation • Conventional GIS model the world in two-dimensions with a map model and geographic features dependent on geometry for definition • This map model limits three-dimensional and temporal analysis, and multidimensional, multi-scale representations • Cognition studies indicate that humans perceive the geographic world as a set of definable entities with spatial, thematic, and temporal attributes associated

4. Objectives • Provide a theoretical model based on feature orientation • Develop the model to support unique entities with spatial, thematic, and temporal attributes and relations for each feature instance • Implement the model in a feature library and use the library for feature extraction to support The National Map

5. Approach • Implement the theoretical feature model in an object-oriented library • Develop feature instances for 20 specific features that are relevant to The National Map • Develop attributes and relationships including multiple representations (raster and vector) of attributes for each feature instance • Determine the extraction capability of each feature from various image sources

6. Feature Model • Feature is geographic entity and object representation • One feature, many objects • Multiple resolutions • Multiple geometries • Access from single identity

8. Definitions • Feature - A set of phenomena with common attributes and relationships. The concept of feature encompasses both entity and object. • Entity - A real-world phenomenon that cannot be subdivided into phenomena of the same kind. • Object - A digital representation of all or a part of an entity. • Attribute - Characteristic of a feature or of an attribute value. • Relationship - Linkage between features or objects. • Feature instance - An occurrence of a feature defined by a unique set of attributes and relationships.

10. Databases Supporting Feature Extraction and Map Generation • Feature Attributes and Relationships • Image • Image Chips • Spectral Responses • Digital Number Ranges for Multimodal Images • Map • Symbol Specifications • Symbol Chips • Inclusion Criteria

11. Feature Library Implementation

13. Multiple Feature InstanceExample with Actual Data

14. Feature Instance Implementation with Actual Water Quality Data

15. Relationship Implementation from NHD

16. Time Attribute Implementation

17. National Map Feature Extraction • Camp Lejeune study site • 20 features selected • All attributes and relationships built based on DLG-E specifications • Image chips extracted for storage as attributes • Spectral responses determined (laboratory and from images)

18. Table of the 20 Features

20. Airport -- DOQ

21. Airport – Ikonos Pan

22. Airport – Ikonos Pan-sharpened

23. Airport – Ikonos MX

24. Airport – SPOT Pan

25. Airport – CIR Photo

26. Trail – DOQ

27. Trail – Ikonos Pan

28. Trail – Ikonos Pan-sharpened

29. Trail – Ikonos MX

30. Trail – SPOT

31. Trail – CIR Photo

32. Trail – Color Photo

33. Airport Map Symbol

34. Trail Map Symbol

35. Geodatabase for the Study Area in ArcCatalog

36. Airport Feature

37. The Study Area – Camp Lejeune, NC

38. Scale Dependent Renderer

39. Trees on 1:30,000-Scale Map

40. Trees on 1:9,000-Scale Map

41. Buildings Rendered as Polygons 1:5,000-Scale Map

42. Buildings Rendered as Polygons/Points Based on the Longest Axis -- 1:12,000-Scale Map

43. Buildings Rendered as Points on 1:28,000-Scale Map

44. Buildings Not Displayed on 1:55,000- Scale Map

45. Conclusions • A theoretical model of features existing in the real world as single geographical entities has been developed • This model shows promise for implementing feature extraction methods and scale-dependent rendering for The National Map • Probabilities for extracting specific features from multimodal sources can be developed based on feature attributes and relationships and appearance in various image sources

46. Multidimensional Data Modeling for Feature Extraction and Mapping E. Lynn Usery usery@usgs.gov ACSM April 19, 2004 http://mcmcweb.er.usgs.gov/carto_research