Google Research

Geometric Overpass Extraction from Vector Road Data and DSMs

  • Joshua Schpok
Proceedings of the 19th ACM SIGSPATIAL international Conference on Advances in Geographic information Systems, 2011 (to appear)


We present a method to extract elevated road structures, typically overpassing other roads, transit lines, and watercourses. The technique uses a digital surface model (DSM) and roughly aligned vector road data and outputs geometry approximating the shape and elevation of the elevated road deck. Our method is robust against noise in DSM elevations and can recover elevated roads partially obscured by trees and other overpasses. We demonstrate our method parallelized over city-wide DSMs, and formulate a confidence metric ranking the fidelity of the reconstruction.

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