Halftone dot-growth technique based on morphological filtering
US7365881B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 19, 2002 |
| Grant date | Apr 29, 2008 |
| Priority date | — |
| Expiry date | Feb 20, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/407
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method for converting an original halftone bitmap image to a color converted halftone bitmap image. A set of asymmetrical morphological filters is provided. The original halftone bitmap image is segmented into blocks and for each block: apply the set of morphological filters to the original halftone bitmap image to produce a set of modified halftone bitmap images; estimate the percent dot area of the original halftone bitmap image and the set of modified halftone bitmap images; a predetermined dot-gain to the percent dot area of the original halftone bitmap image to produce a modified percent dot area; select the modified halftone bitmap image whose percent dot area is closest to the modified percent dot area to produce a block of the color corrected halftone bitmap image; and replace the original halftone bitmap image with the combined blocks of selected modified halftone bitmap image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.