Devices, systems and methods for reducing switching time in a video distribution network

Patent metadata

Field	Value
Publication number	US-9516362-B2
Application number	US-201313764315-A
Country	US
Kind code	B2
Filing date	Feb 11, 2013
Priority date	Feb 10, 2012
Publication date	Dec 6, 2016
Grant date	Dec 6, 2016

Abstract

When switching sources, resolutions or refresh rates in a video distribution network, switching times are reduced by maintaining video lock and security authentication between a video switcher and a video sink. The scaler maintains video lock and security authentication by continuing to generate video timing data during switching events. The scaler also facilitates an aesthetically pleasing transition by generating image content data prior to and after the switching event.

First claim

What is claimed is:

1. A switcher device comprising:
(a) at least two input boards, each of the at least two input boards configured for receiving audiovisual data from a video source over a security protocol link; and
(b) a multiplexer communicatively coupled between the at least two input boards and an output board and configured for dynamically routing audiovisual data from the at least two input boards to the output board, and wherein
the output board is configured for
(i) transmitting audiovisual data to a downstream video sink over a security protocol link, and
(ii) maintaining the security protocol link in an authenticated interface with the downstream video sink during a switching event between the at least two input boards by outputting a continuous stream of uninterrupted video timing data during the switching event and wherein
the output board further comprises a scaler configured for generating the continuous stream of video timing data during the switching event,
the continuous stream of video timing data being generated in the absence of video timing data received from the at least two input boards.

2. The switcher device of claim 1 wherein the switching event is a switch from receiving video from a first source to receiving video from a second source.

3. The switcher device of claim 1 wherein the switching event is a switch from receiving video at a first resolution to receiving video at a second resolution.

4. The switcher device of claim 1 wherein the switching event is a switch from receiving video at a first refresh rate to receiving video at a second refresh rate.

5. The switcher device of claim 1 wherein the scaler is further configured for generating black frames of image content data during the switching event.

6. The switcher device of claim 5 wherein the scaler is configured for continuing to generate black frames of image content data until receiving a sufficient amount of image content data for generating a stable output of converted image content data.

7. The switcher device of claim 1 wherein the scaler generates continuous video timing data at a native resolution of the sink.

8. The switcher device of claim 7 wherein the scaler determines the native resolution of the video sink from Extended Display Identification Data (EDID) information of the video sink.

9. The switcher device of claim 1 wherein the security protocol comprises High-Bandwidth Digital Content Protection (HDCP).

10. The switcher device of claim 9 wherein the continuous stream of video timing data satisfies step three of the HDCP authentication protocol.

11. The switcher device of claim 1 wherein the switcher device comprises a chassis and wherein the output board is disposed on a modular output board configured for being removably inserted into a slot in the housing.

12. The switcher device of claim 1 wherein the output board is external to a housing of the switcher device.

13. The switcher device of claim 12 further comprising an extended transmission board and wherein
(a) the multiplexer routes audiovisual data from the at least two input boards to the output board via the extended transmission board,
(b) the extended transmission board is configured for transmitting audiovisual data to the output board over a security protocol link, and
(c) the output board is further configured for receiving audiovisual data over a security protocol link.

14. The switcher device of claim 1 wherein the output board further comprises an HDMI transmitter.

15. The switcher device of claim 5 wherein the switcher device comprises a processing unit in communication with the multiplexer and the output controller and wherein the processing unit transmits a prepare signal to the output board a predetermined amount of time before transmitting a switch signal to the multiplexer.

16. A switcher device comprising:
(a) at least two input boards, each of the at least two input boards configured for receiving audiovisual data from a video source over an HDCP link;
(b) a multiplexer board comprising:
(i) a multiplexer communicatively coupled between the at least two input boards and an output board and configured for dynamically routing audiovisual data from the at least two input boards to the output board, and
(ii) a processing unit in communication with the multiplexer and the output board and configured for transmitting a switch signal to the multiplexer and a prepare signal to the output board prior to a switching event between the at least two input boards; and

(c) the output board configured for transmitting audiovisual data to a video sink over an HDCP link and comprising
(i) a receiver configured for receiving audiovisual data routed from the multiplexer,
(ii) a scaler configured for converting audiovisual data received via the multiplexer to a native resolution of the video sink, generating a continuous stream of uninterrupted video timing data during the switching event at the native resolution of the video sink during the switching event wherein the continuous stream of uninterrupted video timing data is generated in the absence of video timing data received from the at least two input boards, and generating image content data for a period of time until achieving video lock in response to receiving the prepare signal, and
(iii) a transmitter configured for encrypting and transmitting generated audiovisual data to the video sink over an HDCP interface and maintaining the security protocol link in an authenticated interface with the video sink by outputting the continuous stream of uninterrupted video timing data during the switching event.

17. An output board for a switcher device configured for transmitting audiovisual data to a video sink over a security protocol link, the output board comprising:
(a) a receiver configured for receiving audiovisual data from at least two input boards;
(b) a scaler configured for converting the audiovisual data to a native resolution of the video sink and generating audiovisual data during a switching event between the at least two input boards comprising a continuous stream of uninterrupted video timing data, wherein the continuous stream of uninterrupted video timing data is generated in the absence of video timing data received from the at least two input boards;
(c) a transmitter configured for encrypting and transmitting the output of the scaler and further configured for maintaining the security protocol link in an authenticated interface with the video sink.

18. The output board of claim 17 wherein the switching event is a switch from receiving audiovisual data from a first source to receiving audiovisual data from a second source.

19. The output board of claim 17 wherein the switching event is a switch from receiving audiovisual data at a first resolution to receiving audiovisual data at a second resolution.

20. The output board of claim 17 wherein the switching event is a switch from receiving audiovisual data at a first refresh rate to receiving audiovisual data at a second refresh rate.

21. The output board of claim 17 wherein the scaler is configured for generating image content data during the switching event.

22. The output board of claim 21 wherein the scaler is configured for generating image content data after a switching event until receiving a sufficient amount of audiovisual data to generate a stable output of converted audiovisual data.

23. The output board of claim 22 wherein the scal

Assignees

• Velasco Adolfo
• Jackson Daniel
• Crestron Electronics Inc

Inventors

• Velasco Adolfo
• Jackson Daniel

Classifications

• H04N21/25 Primary

  Management operations performed by the server for facilitating the content distribution or administrating data related to end-users or client devices, e.g. end-user or client device authentication, learning user preferences for recommending movies {(maintenance or administration in data networks H04L41/00)} · CPC title

• H04N21/4402

  involving reformatting operations of video signals for household redistribution, storage or real-time display {(details of conversion of video standards at pixel level H04N7/01; video transcoding H04N19/40; adapting incoming signals to the display format of the display terminal G09G5/005; media handling at the source in data packet switching networks H04L65/764)} · CPC title

• H04N21/4344 Primary

  Remultiplexing of multiplex streams, e.g. by modifying time stamps or remapping the packet identifiers · CPC title

• H04N21/43635

  HDMI · CPC title

• H04N21/4367

  Establishing a secure communication between the client and a peripheral device or smart card · CPC title