Printer driver architecture for reducing band memory
US5727137A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 15, 1995 |
| Grant date | Mar 10, 1998 |
| Priority date | — |
| Expiry date | Dec 15, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/1247
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A system renders a print image while enabling reduction of the size of band memory. The printer driver includes a rendering driver comprising a driver interface, a drawing engine, an image and color library, band buffers and a color converter. The driver interface receives image data and drawing commands and transmits them to the drawing engine. The drawing engine divides the page into a series of bands, applies each drawing command for a band and renders the portion of an object in the band to a temporary buffer. To render an object, the drawing engine applies enhancement functions such as color biasing, image resolution enhancements, inverse dot gain transforms, etc. on the object and then applies a dithering function to convert intended color or gray-scale values of objects in the band to bi-level planar pixel matrices. By applying the dithering function before storing each band in band buffer memory, the size of the requisite band buffer memory is significantly reduced. The drawing engine transfers the rendered object to a band buffer. The color converter converts the band color from a band buffer color format to a printer color format and then transmits the banded image to the…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.