Publica
Hier finden Sie wissenschaftliche Publikationen aus den FraunhoferInstituten. Efficient correspondence search algorithm for GOBO projectionbased realtime 3D measurement
 Harding, K.G. ; Society of PhotoOptical Instrumentation Engineers SPIE, Bellingham/Wash.: Dimensional Optical Metrology and Inspection for Practical Applications VIII : 1617 April 2019, Baltimore, Maryland, United States Bellingham, WA: SPIE, 2019 (Proceedings of SPIE 10991) ISBN: 9781510626478 ISBN: 9781510626485 Paper 1099109, 8 pp. 
 Conference "Dimensional Optical Metrology and Inspection for Practical Applications" <8, 2019, Baltimore/Md.> 

 English 
 Conference Paper 
 Fraunhofer IOF () 
Abstract
Many robotoperated automation tasks require realtime reconstruction of accurate 3D data. While our sensors that are based on GOBO projectionaided stereo matching between two cameras allow for high acquisition frame rates, the 3D reconstruction calculation is really time consuming. In order to find corresponding pixels between cameras, it is necessary to search the best match amongst all pixels within the geometrically possible image area. The wellestablished method for this search is to compare each candidate pixel by temporal cross correlation of the brightnessvalue sequences of both pixels. This is computationally intensive and interdicts fast, realtime applications on standard PC hardware. We introduce a new algorithm, which minimizes the number of calculations needed to compare two pixels down to two binary operations per comparison. To achieve this, we precalculate a bitstring of binary features for each pixel of both cameras. Then, two pixels can be compared by counting the number of bits that differ between the two bit strings. Our algorithm's results are accurate to a few pixels and require a second, cross correlationbased refinement. In practice, our algorithm (including precalculation and refinement step) is much faster than traditional, purely cross correlationbased search, while maintaining a similar level of accuracy.