Hierarchical DEM Refinement Using Surface Parallax
Abstract
We present a multi-resolution approach to update and refine coarse 3D models of urban environments from a sequence of intensity images using surface parallax. A coarse and potentially incomplete depth map of the scene obtained from a Digital Elevation Map (DEM) is used as a reference surface which is refined and updated using this approach. We first estimate the camera motion using the reference depth map. Using the estimated camera motion, at each level in the multi-resolution framework, motion of 3D points on the reference surface is compensated, and the residual flow field, which is an epipolar field, is estimated and used to refine the depth map at that level. At a coarse resolution, the difference between the reference depth and the true depth will be small, leading to a small parallax field. The refined depth map from the coarser level is the propagated to the finer level. Thus, significant deviations of an available model from a true model can be handled using this approach.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 2004
- Accession Number
- ADA431639
Entities
People
- Amit K. Agrawal
- Rama Chellappa
- Reuven Meth
Organizations
- University of Maryland