Patent · US Expired

Means for combining data of different frequencies for a raster output device

USRE35657E · kind E · reissue

5Cited by
13References
42Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 29, 1995
Grant dateNov 11, 1997
Priority date
Expiry dateJun 29, 2015

Classification

  • Technology area (CPC —)General

Abstract

A circuit for enabling the raster display of text or line art in one constant color against a background of another constant color or against a continuous-tone picture, or the display of a continuous-tone picture through an arbitrary shape. The circuit has four channels, one each for constant colors, continuous-tone images, image masks, and instructions. The constant colors are stored in the first channel in the form of two 8-bit colors, one for the text or line art and one for the background. Any color pair can be read from this memory, divided into two 8-bit colors, and presented at two inputs of a final multiplexer. The second channel stores continuous tone color pictures and presents this information at a third input of the multiplexer. The third channel receives masks or outlines in the form of bitmaps and the fourth channel receives instructions which may be run-length encoded. These two channels combine their data, which is then used to control the multiplexer.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.