Time-multiplexed multi-program encryption system
US7590237B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 2005 |
| Grant date | Sep 15, 2009 |
| Priority date | — |
| Expiry date | Jun 16, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/4623
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A system and method are described for greatly increasing the number of services that can be encrypted with existing conditional access equipment. The method is most useful when many digitally compressed programs are encrypted at the same time. Only the most critical components of each compressed video, audio, or data stream are selected and then sequenced into a single stream. Additional formatting causes this sequence of segments from multiple sources to appear as a single continuous stream to the conditional access system. Once this stream has been encrypted, it is demultiplexed and the components are restored and re-sequenced into their respective programs. Messages such as the Entitlement Control Messages that are inserted into the stream by the encryption system, are also adjusted and included with each of the reconstructed programs. The technique not only allows encryption systems to be designed using less encryption hardware, but also simplifies the management of encryption sessions, particularly in on-demand programming applications.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.