Collision detection and avoidance system based on computer vision
A wide selection of stereo matching algorithms have been evaluated for the purpose of
creating a collision avoidance module. Varying greatly in the accuracy, a few of the
algorithms were fast enough for further use.
Two computer vision libraries, OpenCV and MRF, were evaluated for their implementations
of various stereo matching algorithms. In addition OpenCV provides a wide variety of
functions for creating sophisticated computer vision programs and were evaluated on
this basis as well.
A stereo camera were constructed using low cost, of-the-shelf web cameras.
Two low-power platforms, The Pandaboard and the Beaglebone Black, were evaluated as
viable platforms for developing a computer vision module on top. In addition they were
compared to an Intel platform as a reference.
Based on the results gathered, a fast, but simple, collision detector could be made
using the simple block matching algorithm found in OpenCV. A more advanced detector
could be built using semi-global stereo matching. These were the only implementations
that were fast enough. The other energy minimization algorithms (Graph cuts and belief
propagation) did produce good disparity maps, but were too slow for any realistic
In order for the low-power platforms to be fast enough, a combination of improvements
must be used. OpenCV should be compiled with aggressive optimization options enabled
with support for hardware accelerated floating point math. Choice of low-power platform
matters, but it is possible to work around this by reducing the workload.
The most effective speedup that enables the low-power platforms were reducing the
resolution of the images to be matched. When reducing the size of the sub-problems
enough to align with cache size, considerable speedups were found with little
penalty in the corresponding disparity map.
Place, publisher, year, edition, pages
Institutt for teknisk kybernetikk , 2014. , 107 p.
IdentifiersURN: urn:nbn:no:ntnu:diva-24779Local ID: ntnudaim:7123OAI: oai:DiVA.org:ntnu-24779DiVA: diva2:720034
Skavhaug, Amund, Førsteamanuensis