A case is made for the use of regular hexagonal sampling systems in robot vision applications. With such a sampling technique, neighbouring pixels reside in equidistant shells surrounding the central pixel and this leads to the simpler design and faster processing of local operators and to a reduced image storage requirement. Connectivity within the image is easily defined and the aliasing associated with vertical lines in the hexagonal system is not a problem for robot vision. With modern processors only a minimal time penalty is incurred in reporting results in a rectangular coordinate system, and a comparison between equivalent processing times for hexagonal and rectangular systems implemented on a popular processor has shown savings in excess of 40% for hexagonal edge detection operators. Little modification is required to TV frame grabber hardware to enable hexagonal digitisation.

Date Published: 9 February 1989
PDF: 5 pages
Proc. SPIE 1008, Expert Robots for Industrial Use, (9 February 1989);

Published in SPIE Proceedings Vol. 1008:
Expert Robots for Industrial Use
David P. Casasent; Ernest L. Hall; Kenneth J. Stout, Editor(s)