Packet-based video network

• US 20050220194A1
• Filed: 03/30/2005
• Published: 10/06/2005
• Est. Priority Date: 03/31/2004
• Status: Active Grant

• Current Assignee: Sony Europe BV (Sony Group Corp.)
• Original Assignee: Sony Europe Limited (Sony Group Corp.)
• Inventors: Saunders, Nicholas Ian, Compton, Matthew
• Granted Patent: US 8,050,252 B2
• Time in Patent Office: Days
• US Class Current: 375/240.280
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/70 Media network packetisation
• CPC Class Codes: H04L 65/80 Responding to QoS
• CPC Class Codes: H04N 21/242 Synchronization processes, e.g. processing of PCR [Program Clock References] arrangements for synchronising broadcast or distribution via plural systems in broadcast distribution systems H04H20/18
• CPC Class Codes: H04N 21/6437 Real-time Transport Protocol [RTP]
• CPC Class Codes: H04N 5/268 Signal distribution or switching

Abstract

A video data network device arranged to receive a video signal and an associated synchronisation signal and to launch video data packets representing the video signal onto a packet-based data network comprises means for detecting whether the video signal is synchronised with the synchronisation signal; and means for launching data onto the network indicating whether the video signal is synchronised with the synchronisation signal.

Claims

1. A video data network device arranged to receive a video signal and an associated synchronisation signal and to launch video data packets representing said video signal onto a packet-based data network, said device comprising:

a detector to detect whether said video signal is synchronised with said synchronisation signal; and

a launcher to launch data onto said network indicating whether said video signal is synchronised with said synchronisation signal.

2. A device according to claim 1, in which said data indicating whether said video signal is synchronised with said synchronisation signal comprises a data flag of one or more bits within at least a subset of said video data packets.

3. A device according to claim 2, in which said data indicating whether said video signal is synchronised with said synchronisation signal comprises a data flag of one or more bits within a packet header of at least a subset of said video data packets.

4. A device according to claim 1, in which said video data packets are Real Time Protocol (RTP) data packets.

5. A device according to claim 3, in which said video data packets are BT.656 data packets.

6. A device according to claim 5, in which said data flag is carried within said BT.656 packet header.

7. A device according to claim 1, comprising logic to launch packets onto said network carrying data representing the frequency and/or phase of said synchronisation signal.

14. A video data network comprising:

one or more devices according to claim 1;

one or more devices arranged to receive from a packet-based network;

video data;

timing data indicating the frequency and/or phase of a reference synchronisation signal; and

synchronisation data indicating whether said video data at said source device was synchronised with said reference synchronisation signal; and

comprising;

logic to synchronise a local synchronisation signal to said reference synchronisation signal using said timing data;

logic to output said video data in accordance with said local synchronisation signal; and

logic to associate an indicator with said video data in dependence on said synchronisation data; and

a network connection providing data communication between said devices.

8. A video data network device arranged to receive from a packet-based network:

video data;

timing data indicating the frequency and/or phase of a reference synchronisation signal; and

synchronisation data indicating whether said video data at said source device was synchronised with said reference synchronisation signal;

said device comprising;

logic to synchronise a local synchronisation signal to said reference synchronisation signal using said timing data;

logic to output said video data in accordance with said local synchronisation signal; and

logic to associate an indicator with said video data in dependence on said synchronisation data.

9. A device according to claim 8, in which said indicator comprises a visible modification of said video data.

10. A device according to claim 9, in which said indicator comprises a modification of the appearance of at least some pixels represented by said video data.

11. A device according to claim 10, in which said indicator comprises a readable message superposed on at least a portion of images represented by said video data.

12. A device according to claim 9, in which said indicator comprises a modification of the phase of said video data with respect to said local synchronisation signal.

13. A device according to claim 12, in which said indicator comprises a modification of said phase of said video signal so as to simulate a frame roll.

15. A method of operation of a video data network device arranged to receive a video signal and an associated synchronisation signal and to launch video data packets representing said video signal onto a packet-based data network, said method comprising the steps of:

detecting whether said video signal is synchronised with said synchronisation signal; and

launching data onto said network indicating whether said video signal is synchronised with said synchronisation signal.

20. A providing medium by which computer software having program code for carrying out a method according to claim 15 is provided.

21. A medium according to claim 20, said medium being a storage medium.

22. A medium according to claim 20, said medium being a transmission medium.

16. A method of operation of a video data network device arranged to receive from a packet-based network:

video data;

timing data indicating the frequency and/or phase of a reference synchronisation signal; and

synchronisation data indicating whether said video data at said source device was synchronised with said reference synchronisation signal;

said method comprising the steps of;

synchronising a local synchronisation signal to said reference synchronisation signal using said timing data;

outputting said video data in accordance with said local synchronisation signal; and

associating an indicator with said video data in dependence on said synchronisation data.

17. A providing medium by which computer software having program code for carrying out a method according to claim 16 is provided.

18. A medium according to claim 17, said medium being a storage medium.

19. A medium according to claim 17, said medium being a transmission medium.

23. A video data packet having:

a packet header; and

payload video data representing a portion of a video signal;

said packet carrying data indicating whether said video signal was synchronised with a reference synchronisation signal when said packet was assembled.