Shadow detection and compensation in aerial images with an application to building height estimation

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Date

2010

Author

Şeref, Ahmet

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This thesis is devoted to the shadow detection and compensation in aerial images with application of the detection results to building height detection. Shadows could be defined as the parts of the scene that is not directly illuminated by a light source due to obstructing object or objects. Usually the shadows in images or video are undesirable, since they could cause degradation of the expected results during processing of the image or video for object detection, segmentation, scene surveillance or similar purposes. However shadow information could also be used for beneficial purposes like revealing information about the object’s shape, orientation and even about the light source. In this thesis firstly shadow detection methods are overviewed. Beside the selected methods from literature, some novel approaches are also proposed and experimented. Then shadow compensation methods are overviewed and experimented. Finally an example of beneficial utilizations of shadow information is studied, where buildings’ heights are estimated from their shadow length and sun angles.

Subject Keywords

Photography, Aerial., Electrical engineering, Electronics, Nuclear engineering., Electrical engineering

URI

http://etd.lib.metu.edu.tr/upload/12612560/index.pdf
https://hdl.handle.net/11511/20316

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

A. Şeref, “Shadow detection and compensation in aerial images with an application to building height estimation,” M.S. - Master of Science, Middle East Technical University, 2010.