Secure spread spectrum watermarking for multimedia data
US6208735A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 28, 1999 |
| Grant date | Mar 27, 2001 |
| Priority date | — |
| Expiry date | Jan 28, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B20/00891
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Digital watermarking of audio, image, video or multimedia data is achieved by inserting the watermark into the perceptually significant components of a decomposition of the data in a manner so as to be visually imperceptible. In a preferred method, a frequency spectral image of the data, preferably a Fourier transform of the data, is obtained. A watermark is inserted into perceptually significant components of the frequency spectral image. The resultant watermarked spectral image is subjected to an inverse transform to produce watermarked data. The watermark is extracted from watermarked data by first comparing the watermarked data with the original data to obtain an extracted watermark. Then, the original watermark, original data and the extracted watermark are compared to generate a watermark which is analyzed for authenticity of the watermark.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.