Digital watermark detecting with weighting functions
US6751337B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 26, 2002 |
| Grant date | Jun 15, 2004 |
| Priority date | — |
| Expiry date | Aug 26, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/018
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A digital watermark detector uses weighting functions to enhance watermark detection. The weighting function applies more weight to parts of a digitally watermarked signal that are more robust to distortion. As such, the method provides for more reliable watermark detection, especially in applications where distortions, such as lossy compression or analog conversion, more accurate detection more difficult. In one version of the method, the detector projects the watermarked signal into a pseudorandom direction specified by a key, applies the weighting function, and extracts auxiliary data symbols from the projected signal by quantizing the projected signal and deriving the symbol values based on the quantization.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.