Embedding digital watermarks in spot colors
US6763124B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 11, 2002 |
| Grant date | Jul 13, 2004 |
| Priority date | — |
| Expiry date | May 29, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/327
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention relates to digitally watermarking spot colors. Spot colors are represented as digital files including a set of intensity values. These intensity values correspond to the amount or percentage of spot color ink that should be applied to a pixel, a group of pixel or to an image area. A watermark signal component including luminance value adjustments is converted to intensity value adjustments. These intensity value adjustments are applied to the spot color digital file to facilitated digital watermark embedding. In another embodiment, an adjustment is made to the intensity values to compensate for noise introduced by a scanner, camera or color conversion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.