Method of creating and applying half tone screen patterns
US5187594A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 9, 1990 |
| Grant date | Feb 16, 1993 |
| Priority date | — |
| Expiry date | Feb 9, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/4058
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A technique for creating and applying half tone screen patterns by computer, consisting of a screen generator and a screen applicator. The screen generator accepts a set of parameters specifying the angle and frequency of the desired screen, the output printing device resolution, and parameter tolerances. It then produces a half tone screen pattern file according to the specified parameters, as a set of repeat arrays for each desired gray level. The screen applicator accepts an input contone image representation such as is produced by a scanner or other device, and the half tone screen pattern file produced by the screen generator. It then interpolates between the pixel values, at the output device resolution, by examining the repeat arrays for each device cell. In this way, a representation of a half tone screening of the input contone image results where the output device resolution is fully exploited.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.