Generation of encrypted video information
US7681227B2 · kind B2 · utility
11Cited by
7References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 20, 2004 |
| Grant date | Mar 16, 2010 |
| Priority date | — |
| Expiry date | Jun 26, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/4623
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An encrypted stream of video information (20) contains first video frames (22) and second video frames which are accessible and not accessible during trick play respectively. From a source stream encrypted that is for decryption with repeatedly changing control words sections of the stream are identified where respective first ones of the frames occur in the stream. Control words for decryption (24) are included in the stream. At least part of the control words are included in the stream at positions selected synchronized to the identified sections.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.