Showing papers by "Charles R. Dyer published in 1980"
TL;DR: This paper presents an algorithm for converting from quadtrees to a simple class of boundary codes and is shown to have an execution time proportional to the perimeter of the region.
Abstract: There has been recent interest in the use of quadtrees to represent regions in an image. It thus becomes desirable to develop efficient methods of conversion between quadtrees and other types of region representations. This paper presents an algorithm for converting from quadtrees to a simple class of boundary codes. The algorithm is shown to have an execution time proportional to the perimeter of the region.
173 citations
TL;DR: Real-time acceptors are presented for many of the languages that have been shown to be accepted by conventional two-way acceptors, including several classes of context-free languages.
Abstract: This paper studies a restriction of one-dimensional bounded cellular automata in which information is allowed to move only in one direction. Real-time acceptors are presented for many of the languages that have been shown to be accepted by conventional two-way acceptors, including several classes of context-free languages.
134 citations
TL;DR: The local property-counting techniques used with an array representation are generalized to counting local node configurations in a quadtree and the average running time of the algorithm is proportional to the product of the number of the leaf nodes in the quadtree.
106 citations
12 citations
TL;DR: Given a binary image containing a connected component, parallel propagation algorithms are presented for constructing upright and 45°-tilted framing rectangles around the component in time proportional to the sum of the dimensions of these rectangles.
3 citations