![]() |
Graphics Dithering - What Is It And When Is I |
The information in this document applies to:
WordPerfect® 5.1 for DOS
Problem
Symptoms: Why does WP do dithering? When does WP do dithering? Does it only do it on bitmapped images or does it do it on all images? Is dithering in WP used specifically for scanned images or does it serve other purposes also? Solutions: Newspapers and magazines use halftoning to simulate shades of gray by varying the size of circular black dots on a fixed grid pattern. Dithering, a kind of halftoning, also simulates shades of gray--but by varying the patterns of identically shaped dots. WP does not halftone or put a dither pattern on an image unless there is gray scaling information present. If the there is no gray scaling, WP will just bring in the image. The problem with working on images that are already halftoned is that you cannot scale them in WP without causing a pattern grid to appear. For more information on this subject, read the article "Scanning Safari" by Steve Roth in the April 1989 issue of WP magazine. Also, there is more information in Folio memos 19246T and 16154W. Most of the files that customers have sent in for inspection show some faulty values in the prefix for dots per inch, or resolution. Specialists need to look at each individual file though, to determine if WP is not reading it correctly, or if the file bad. |
Answer:
Details:
Product specifications, packaging, technical support and information (*Specifications*) refer to theUnited States retail English version only. Specifications for other versions may vary. All Specifications, claims, features, representations, and/or comparisons provided are correct to the best of our knowledge of the date of publication, but are subject to change without notice.OUR MAXIMUM AGGREGATE LIABILITY TO YOU AND THAT OF OUR DEALERS AND SUPPLIERS IS LIMITED. IT SHALL NOTEXCEED THE AMOUNT YOU PAID TO ACCESS THE INFORMATION. SEE LEGAL DISCLAIMER. |