Secure device for the broadcasting, recording and viewing on demand of audiovisual works in a format of the MPEG-2 TS type
A process for distributing audiovisual sequences in accordance with a nominal stream format respecting a MPEG-2 TS norm including a succession of TS packets, including analyzing the stream made prior to transmitting to client equipment to generate a first stream in conformity with the MPEG-2 TS format, modifying all or part of the TS packets by substituting packets of the same structure, but whose content was modified, and generating a second stream of a format including digital information suitable for permitting reconstruction of the nominal stream, separately transmitting the two streams from a servers to the equipment, and a calculation is made on the equipment of a synthesis of a stream in nominal format as a function of the first stream and the second stream.
1. A process for distributing audiovisual sequences in accordance with a nominal stream format respecting a MPEG-2 TS norm comprising a succession of TS packets, comprising:
analyzing the stream made prior to transmitting to client equipment to generate a first stream in conformity with the MPEG-2 TS format,
modifying all or part of the TS packets by substituting modified packets of the same structure and size whose content is of primary importance for viewing,
generating a second stream of a format comprising digital information suitable to permit reconstruction of the nominal stream,
separately transmitting the two streams from a server to the client equipment, and
calculating a synthesis of a stream in nominal format as a function of the first stream and the second stream on the client equipment.
2. The process according to claim 1 , wherein the substituted TS packets contain information relative to one or several video streams included in the TS stream.
3. The process according to claim 1 , wherein the substituted TS packets contain information relative to one or several audio streams included in the TS stream.
4. The process according to claim 1 , wherein analyzing the stream comprises a stage for determination of the TS packets to be substituted as a function of their content.
5. The process according to claim 1 , wherein only certain parts of content of the substituted packets are actually modified.
6. The process according to claim 1 , wherein the second stream contains the substituted TS packets stemming from the nominal stream.
7. The process according to claim 1 , wherein the second stream contains data necessary for effecting substitutions of bytes to be applied in the first stream to obtain the nominal stream.
8. The process according to claim 1 , wherein the first stream is modified by modification of values of all or part of indicator fields.
9. The process according to claim 1 , wherein the second stream respects the MPEG-2 TS format.
10. The process according to claim 1 , wherein the first stream has the same size in bytes as the original stream in MPEG-2 TS format.
11. The process according to claim 1 , wherein the first stream and the second stream are transmitted to the equipment via the same communication network.
12. The process according to claim 1 , wherein the second stream in encrypted.
13. The process according to claim 11 , wherein the second stream is multiplexed in the first stream.
14. The process according to claim 12 , wherein the second stream is multiplexed in the first stream.
15. Equipment that fabricates a video stream according to claim 1 , comprising at least one multimedia server containing original video sequences and a device for analyzing the video stream coming from the server for generating the two streams.
16. Equipment that exploits a video stream according to claim 1 , comprising a standard reader of MPEG-2 TS streams, at least one recording interface for storing the content of the first stream and at least one display interface, and means for recomposition of the original stream from the two streams.
17. A system that transmits a video stream according to claim 1 comprising equipment that produces the video stream comprising at least one multimedia server containing original video sequences and a device for analyzing the video stream coming from the server for generating the two streams, at least one piece of equipment for exploiting a video stream comprising a standard reader of MPEG-2 TS streams, at least one recording interface for storing the content of the first stream and at least one display interface, means for recomposition of the original stream from the two streams, and at least one communication network between the production equipment and the piece or pieces of exploitation equipment.