Apparatus for and method of embedding and extracting digital information, and medium having program for carrying out the method recorded thereon
US6693965B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 21, 2000 |
| Grant date | Feb 17, 2004 |
| Priority date | — |
| Expiry date | Jan 21, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/327
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A digital information embedding apparatus comprises a band divider, a block divider, a key generator, an information embedder and a band synthesizer. The band divider divides the digital image signal into a plurality of frequency bands to obtain wavelet coefficients. The block divider divides the frequency band in which the digital information is to be embedded into a plurality of blocks in a predetermined block size. The key generator respectively generates secondary keys having different values from a key having a predetermined value using a predetermined function. The information embedder specifies the block in the embedding object region based on each of the generated secondary keys, and respectively embeds the corresponding information composing the digital information in the wavelet coefficients in the specified block in the embedding object region. The band synthesizer reconstructs a digital image signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.