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Author Barrett, R. C. ♦ Jordan, B. W.
Source ACM Digital Library
Content type Text
Publisher Association for Computing Machinery (ACM)
File Format PDF
Language English
Subject Keyword Graphics ♦ Raster plotter ♦ Line drawing ♦ Dot generation ♦ Discrete image ♦ Scan conversion
Abstract Most graphics systems using a raster scan output device (CRT or hardcopy) maintain a display file in the XY or random scan format. Scan converters, hardware or software, must be provided to translate the picture description from the XY format to the raster format. Published scan conversion algorithms which are fast will reserve a buffer area large enough to accommodate the entire screen. On the other hand, those which use a small buffer area are slow because they require multiple passes through the XY display file. The scan conversion algorithm described here uses a linked list data structure to process the lines of the drawing in strips corresponding to groups of scan lines. A relatively small primary memory buffer area is used to accumulate the binary image for a group of scan lines. When this portion of the drawing has been plotted, the buffer is reused for the next portion. Because of the list processing procedures used, only a single pass through the XY display file is required when generating the binary image and only a slight increase in execution time over the fully buffered core results. Results show that storage requirements can be reduced by more than 80 percent while causing less than a 10 percent increase in execution time.
Description Affiliation: Northwestern Univ., Evanston, IL (Jordan, B. W.) || Hughes Aircraft Co., Culver City, CA (Barrett, R. C.)
Age Range 18 to 22 years ♦ above 22 year
Educational Use Research
Education Level UG and PG
Learning Resource Type Article
Publisher Date 2005-08-01
Publisher Place New York
Journal Communications of the ACM (CACM)
Volume Number 16
Issue Number 11
Page Count 7
Starting Page 676
Ending Page 682

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Source: ACM Digital Library