Embedding frequency modulation infrared watermark in digital document
US8064102B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 1, 2010 |
| Grant date | Nov 22, 2011 |
| Priority date | — |
| Expiry date | Jul 1, 2030 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S283/902
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
Embodiments are disclosed for generating an infrared mark indicator comprised of security information in a printed image. Image data is rendered to a CMYK image. A black plane of the CMYK image is separated and transformed to a frequency domain wherein the frequency components are alternated to encode the watermarking message. The CMY values are selected based on the encoded black value in order to maintain a same color appearance image for the printed image under a normal visual light illuminant. The image data is printed on the substrate in accordance with the transformed planes wherein upon the resultant printed image being exposed to infrared illuminant, a print pattern is detectable as an infrared mark when scanned with an infrared sensing device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.