Local Flextream over internet protocol
View Patent ↗The invention relates to the field of digital television. More exactly, the invention deals with video compression equipments inside television head-ends, which comprise encoders grouped in encoding pools for statistical multiplexing. The invention also concerns of a method for driving individual output bitrates for encoders gathered in such encoding pool. The present invention concerns an encoding pool comprising a master encoder MVE and at least one slave encoder SVEi, each encoder MVE, SVEi receiving an uncompressed video stream UM, USi and issuing an encoded stream TM, TSi via a first extremity of an IP link IPLM, IPLi, all second extremities of said IP links IPLM, IPLi being bound to a switch IPS, the at least one slave encoder SVEi sending a piece of information on the complexity Cli of the uncompressed video stream USi, the master encoder MVE evaluating an allocation for output bitrate BRi of the at least one slave encoder SVEi from the piece of information on the complexity Cli and sending said allocation BRi to the at least one slave encoder SVEi. According to the invention, the piece of information on the complexity Cli and the allocation for output bitrate BRi are transmitted via a path P i comprising the IP link IPLi, the switch IPS and the IP Link IPM.
1. Encoding pool comprising a master encoder and at least one slave encoder, each encoder receiving an uncompressed video stream and issuing an encoded video stream via a first extremity of an IP link, all second extremities of said IP links being bound to a switch, the at least one slave encoder sending a piece of information on the complexity of the corresponding received uncompressed video stream, the master encoder evaluating an allocation for output bitrate of the at least one slave encoder from the piece of information on the complexity and sending said allocation to the at least one slave encoder, wherein the piece of information on the complexity and the allocation for output bitrate are transmitted via a path comprising the IP link connecting the slave encoder and the switch, the switch and the IP Link connecting the master encoder and the switch.
2. Encoding pool according to claim 1 , wherein the encoders of the pool are designed for supporting IEEE1588 protocol.
3. Encoding pool according to claim 2 , wherein each slave encoder sends, simultaneously to the piece of information on the complexity, a timestamp representative of the date of sending of said piece of information.
4. Encoding pool according to claim 3 , wherein the master encoder evaluates the timestamp for qualifying the pertinence of the piece of information on the complexity.
5. Encoding pool according to claim 3 , wherein the switch is designed for supporting IEEE1588 protocol.
6. Encoding pool according to claim 1 , wherein the IP links are Ethernet links.
7. Method for driving individual output bitrates for encoders gathered in an encoding pool, said encoding pool comprising a master encoder and at least one slave encoder, each encoder receiving an uncompressed video stream (UM, USi) and issuing an encoded video stream with said output bitrate via a first extremity of an IP link, a second extremity of said IP links being bound to a switch, wherein it comprises:
A step for sending, by the at least one slave encoder to the master encoder, a piece of information on the complexity of the uncompressed video stream it receives, via a path comprising the IP link, the switch and the IP Link;
A step for evaluating by the master encoder an allocation for output bitrate for the at least one slave encoder from the piece of information on the complexity;
A step for sending the allocation for output bitrate by the master encoder to the at least one slave encoder via the path; and
A step for issuing encoded stream by the at least one slave encoder at the allocated output bitrate.
8. Method according to claim 7 wherein the sending step further comprises an emission of a timestamp representative of the date at which the sending of the piece of information on the complexity is performed.
9. Method according to claim 8 , wherein the evaluating step starts with an evaluation of the timestamp for qualifying pertinence of the piece of information on the complexity.
10. Method according to claim 8 , wherein it involves a synchronization mechanism for insuring the bitrates changes for are synchronous on all slave encoders.