Adjacency detection using quadcodes

ABSTRACT

A method is presented for determining whether two given regions are adjacent, and for finding all the neighbors of different sizes for a given region. Regions are defined as elementary squares of any size. In a companion paper [2], we introduce the quadcode and discuss its use in representing geometric concepts in the coded image, such as location, distance, and adjacency. In this paper we give a further discussion of adjacency in terms of quadcodes. Gargantini [1] discussed adjacency detection using linear quadtrees. Her discussion was applied to pixels, and a procedure was given to find a pixel's southern neighbor only. This paper considers elementary squares of any size, and gives procedures for both aspects of the problem: for determining whether two given regions are adjacent, and for finding all the neighbors of different sizes for a given region.

REFERENCES

• 1: Irene Gargantini, An effective way to represent quadtrees, Communications of the ACM, v.25 n.12, p.905-910, Dec 1982 [doi>10.1145/358728.358741]
• 2: Shu-Xiang Li , Murray H. Loew, The quadcode and its arithmetic, Communications of the ACM, v.30 n.7, p.621-626, July 1987 [doi>10.1145/28569.28573]

INDEX TERMS

Classification:
  E. Data

  I. Computing Methodologies
  I.4 IMAGE PROCESSING AND COMPUTER VISION
      I.4.2 Compression (Coding)
          Subjects: Exact coding**
      I.4.6 Segmentation
          Subjects: Pixel classification; Region growing, partitioning
  I.5 PATTERN RECOGNITION
      I.5.4 Applications
          Subjects: Computer vision

General Terms:
Algorithms, Performance