Results 261 to 270 of about 8,134 (290)

Skeletonizing the distance transform on the hexagonal grid

[1988 Proceedings] 9th International Conference on Pattern Recognition, 2003
An efficient skeletonizing algorithm is presented for the hexagonal grid. The skeleton has unit width, except at crossings and in regions of the shape having even width. Otherwise the skeleton has all the properties generally required for correct skeletons.
G Borgefors, G Sanniti di Baja
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A hexagonal Fourier model of grid cells

Hippocampus, 2018
AbstractGrid cells in rat medial entorhinal cortex are widely thought to play a major role in spatial behavior. However, the exact computational role of the population of grid cells is not known. Here we provide a descriptive model, which nonetheless considers biologically feasible mechanisms, whereby the grid cells are viewed as a two‐dimensional ...
Ulises Rodríguez‐Domínguez, Jeremy B. Caplan   +1 more
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Geometric transformations on the hexagonal grid

IEEE Transactions on Image Processing, 1995
The hexagonal grid has long been known to be superior to the more traditional rectangular grid system in many aspects in image processing and machine vision related fields. However, systematic developments of the mathematical backgrounds for the hexagonal grid are conspicuously lacking. The purpose of this paper is to study geometric transformations on
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Go Without Ko on Hexagonal Grids [PDF]

ICGA Journal, 2012
The note explains why the ko rule, which is essential for the game of Go, is not needed for hexagonal versions of the game. This known property was recently re-discovered through an evolutionary search for new games.
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Drawing conics on a hexagonal grid

Proceedings Fifth International Conference on Information Visualisation, 2002
An algorithm is presented which can be used to outline ellipses, circles, or any of the other conic sections on a hexagonal lattice. The basic algorithm requires just one test and three add operations in the inner loop, though an additional test is required to detect a change in the overall direction between two adjacent sectants.
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Potentials on the hexagonal grid

Circuits Systems and Signal Processing, 1997
The author considers the problem of determining the potentials at the vertices of a uniform hexagonal grid when the difference of potential is given between two of them. The result is obtained as the Fourier transform of a distribution on a two-dimensional torus. A discussion is also given of the Green's function for the system.
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Optimal halftoning over hexagonal grids

SPIE Proceedings, 2006
Halftoning approaches to image rendering on binary devices have traditionally relied on rectangular grids for dot placement. This practice has been followed mainly due to restrictions on printer hardware technology. However, recent advances on printing devices coupled with the availability of efficient interpolation and resampling algorithms are making
Jan Bacca Rodríguez, Alvaro J. González, Gonzalo R. Arce, Daniel Leo Lau   +3 more
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Bounds for Codes Identifying Vertices in the Hexagonal Grid

SIAM Journal on Discrete Mathematics, 2000
In an undirected graph \(G=(V,E)\), a subset \(C\) of \(V\) is called an identifying code of the sets \(B_1(v)\cap C\) consisting of all elements of \(C\) within distance one from the vertex \(v\) if these sets are nonempty and different. The authors take as \(G\) the infinite hexagonal grid graph and show that the density of any identifying code is at
Gérard D. Cohen, Iiro S. Honkala, Antoine Lobstein, Gilles Zémor   +3 more
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Image reconstruction with a hexagonal grid

2002 IEEE Nuclear Science Symposium Conference Record, 2003
Conventional image reconstruction methods use a square grid for ease of calculation or display of the image. On a square grid there are two possible ways to define neighboring pixels. We can either regard pixels as neighbors when they have a common edge or when they have at least one common corner, so that four and eight neighbors exist (a 4 ...
A. Yabushita, K. Ogawa
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A generalized methodology for the gridding of microarray images with rectangular or hexagonal grid

Signal, Image and Video Processing, 2015
Microarrays provide a simple way to measure the level of hybridization of known probes of interest with one or more samples under different conditions. The rapid development of microarray technology requires the implementation of smart and flexible algorithms to deal either with the great amount of data or with the variations of the used hardware.
Nikolaos Giannakeas, Fanis G. Kalatzis, Markos G. Tsipouras, Dimitrios I. Fotiadis   +3 more
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