Anti-aliasing for digital printing
US6654147B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 6, 1999 |
| Grant date | Nov 25, 2003 |
| Priority date | — |
| Expiry date | Jul 6, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2200/12
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The present invention presents method and apparatus for anti-aliasing elements in pages containing variable information, to be printed by a digital printer. Each page element is pre-rasterized to a resolution higher by a given factor than the output resolution, and the pixels that belong to non-printable areas are denoted ‘Background’. During the anti-aliasing (averaging) process, each new pixel gets an attribute value, dependent on the higher resolution pixels that contributed to the new pixel:Background—if all contributing pixels were denoted ‘Background’.Opaque—if all contributing pixels were denote ‘Non-Background’.Semi-Background—if the contributing pixels were partly ‘Background’ and partly ‘Non-Backgroun’.One or two intermediate frame buffers serve to assemble sequentially, for each element, the pixel's value, when it is defined as ‘Opaque’, and the calculated new value, when it is defines as ‘Semi-Background’. A merging mechanism computes the final output value of each pixel using the values and attributes assigned to it.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.