Automated Mapping of Streams
Student thesis: Master Thesis and HD Thesis
- Mette Lund Jensen
- Jakob Hjorth Hansen
- Martin Hertz Sørensen
4. semester, Surveying, Planning and Land Management (cand.geom.), Master (Master Programme)
This report addresses automated mapping of streams in the context of climate changes and environmental management. The report has a holistic approach to addressing the mapping of the streams. Four products are mapped: The water’s edge line, the center of the stream, the shoulder break points and the cross section.
The method uses remote sensing data: multispectral images and a digital terrain model. The stream and its geometrical course is enhanced in a combined photo with the multispectral image, a relative terrain model and band ratios with the near infra red band (NDVI and blue/NIR).
The water’s edge line and the center of the stream are mapped by image classification, and its result is used to outline the stream. The cross section is produced orthogonal on the center and by interpolation of the profile point in the TIN-model made of the digital terrain model. The shoulder break point is mapped by evaluating the height relation within the cross section.
The accuracy of the products exceeds the defined requirements, however the method does still hold potential for mapping. Possible solutions for handling problems are listed in the report, and an improved terrain model is regarded as a big step towards improving the results.
The method uses remote sensing data: multispectral images and a digital terrain model. The stream and its geometrical course is enhanced in a combined photo with the multispectral image, a relative terrain model and band ratios with the near infra red band (NDVI and blue/NIR).
The water’s edge line and the center of the stream are mapped by image classification, and its result is used to outline the stream. The cross section is produced orthogonal on the center and by interpolation of the profile point in the TIN-model made of the digital terrain model. The shoulder break point is mapped by evaluating the height relation within the cross section.
The accuracy of the products exceeds the defined requirements, however the method does still hold potential for mapping. Possible solutions for handling problems are listed in the report, and an improved terrain model is regarded as a big step towards improving the results.
Language | Danish |
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Publication date | 13 Jun 2013 |
Number of pages | 193 |