Dehalftoning of digital images
US6020897A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 1997 |
| Grant date | Feb 1, 2000 |
| Priority date | — |
| Expiry date | Dec 22, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T11/60
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Methods and apparatus for blending graphics objects. In one aspect, a method includes receiving a first graphics object; rendering the first graphics object to produce a first pixel map having a first bit depth; increasing a bit depth of a second pixel map associated with a second graphics object that is to be blended with the first graphics object, where the second bit depth is less than the first bit depth; and blending the first and second pixel maps. The method may be implemented to blend graphics objects received by a printing device. In one embodiment, the invention features blending deep pixel data received by a printing device with corresponding shallow halftoned data stored in a shallow frame buffer. The invention may be implemented as a printer configured to receive a page description language description of a page to be printed, the printer including a dehalftone engine for deriving deep pixel data values for objects stored in a shallow frame buffer. In another aspect, the invention features using a pixelmap representative of underlying graphics data for transfer between a host and a remote device by transmitting a halftone representation of the pixelmap from the host to…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.