Accession Number : AD0763439

Title :   Computer Processing of Line Drawings.

Descriptive Note : Technical rept.,

Corporate Author : NEW YORK UNIV BRONX DEPT OF ELECTRICAL ENGINEERING AND COMPUTER SCIENCE

Personal Author(s) : Freeman,Herbert

Report Date : MAY 1973

Pagination or Media Count : 95

Abstract : The paper describes various forms of line-drawing representation, compares different schemes of quantization, and reviews the manner in which a line drawing can be extracted from a tracing or a photographic image. The subjective aspects of a line drawing are examined. Different encoding schemes are compared, with emphasis on the so-called chain code which is convenient for highly irregular line drawings. The properties of chain-coded line drawings are derived, and algorithms are developed for analyzing line drawings to determine various geometric features. Procedures are described for rotating expanding, and smoothing line structures, and for establishing the degree of similarity between two contours by a correlation techniques. Some of the applications described include map matching, optimum two-dimensional layout, the searching of a contour map for a specific terrain elevation profile, and the automatic assembly of jig-saw puzzles. (Author)

Descriptors :   (*COMPUTER PROGRAMMING, GRAPHICS), PATTERN RECOGNITION, CHARACTER RECOGNITION, PICTURES, PHOTOINTERPRETATION

Subject Categories : Computer Programming and Software
      Computer Hardware

Distribution Statement : APPROVED FOR PUBLIC RELEASE