Method for embedding and reading watermark-information in digital form, and apparatus thereof
US6185312A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 27, 1998 |
| Grant date | Feb 6, 2001 |
| Priority date | — |
| Expiry date | Jan 27, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/327
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An apparatus for embedding information comprises: a blocking step for dividing data to be processed into blocks; an orthogonal transform step for obtaining coefficients by carrying out orthogonal transformation for each block; an embedding coefficient selecting step for determining coefficients in which the watermark-information will be embedded by using a random sequence which is generated by initial value; an information embedding step for sequentially embedding the watermark-information, which has arbitrary length of bits, by quantizing value of said coefficients using a predetermined value for quantization; and an inverse orthogonal transform step for carrying out inverse orthogonal transformation for modified coefficients to form block in which the watermark-information is embedded, as well as combining the divided blocks and reconstructing the original form.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.