VIDEO TRANSMISSION SYSTEM AND VIDEO RELAYER DEVICE

• US 20100251319A1
• Filed: 03/31/2010
• Published: 09/30/2010
• Est. Priority Date: 03/31/2009
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: SAWADA, Junichi
• Granted Patent: US 8,196,173 B2
• Time in Patent Office: Days
• US Class Current: 725/119
• CPC Class Codes: H04N 21/6583 Acknowledgement
• CPC Class Codes: H04N 21/8455 involving pointers to the content, e.g. pointers to the I-frames of the video stream

Abstract

A video relayer device includes a processing unit and a memory. The processing unit includes: a key information transfer section to transfer first key information to a video content sink upon receiving the first key information from a video content source having a timer, and a timer pausing section to control the timer of the sink to pause upon receiving the first key information from the source. The processing unit is operable to receive second key information and a calculation result from the sink and store the same, respectively in the memory. The processing unit further includes a timer resuming section to control the timer of the source to resume when the second key information and the calculation result have been stored, respectively, in the memory.

Claims

1. A video transmission system including a video content source, a video content sink, and video relayer devices, at least one of the video relayer devices comprising:

a processing unit;

a memory to store a calculation result and second key information, the calculation result being produced by the sink based upon first key information, and the second key information being associated with a second key held by the sink;

the processing unit being configured to include,

a key information transfer section to transfer first key information to the sink upon receiving the first key information from the source, the first key information being associated with a first key held by the source;

a timer pausing section to control the timer of the source to pause upon receiving the first key information from the source;

the processing unit being operable to receive the second key information and the calculation result from the sink and store the same, respectively, in the memory; and

the processing unit being further configured to include,

a timer resuming section to control the timer to resume when the second key information and the calculation result have been stored, respectively, in the memory.

2. The video transmission system according to claim 1,

wherein upon receiving the first key information from the source, the timer pausing section is further operable to notify the source that the source and the sink are not connected and to control the timer to pause by turning off a hot-plug signal, and

wherein, when the second key information and the calculation result have been stored in the memory, respectively, the timer resuming section is further operable to notify the source that the source and the sink are connected and to control the timer to resume by transmitting a hot-plug signal.

3. A computer-readable medium comprising computer-executable instructions for performing a method, execution of which by the computer facilitates video transmission in circumstances of a video transmission system including a video content source that has a timer, a video content sink and video relayer devices, the method including:

transferring first key information to the sink upon receiving the first key information from a source;

receiving second key information from the sink and storing the same, the second key information being associated with a key held by the sink;

pausing the timer of the source upon receiving the first key information from the source;

receiving a calculation result from the sink and storing the same, the calculation result being a value produced by the sink based upon the first key information; and

controlling the timer to resume when the second key information and the calculation result have been stored, respectively.

4. The computer-readable medium according to claim 3,

wherein pausing operation of the timer includes turning off a hot-plug signal which indicates to the source that the source and the sink are not connected, and

wherein resuming operation of the timer is resumed by transmitting a hot-plug signal to the source which indicates to the source that the source and the sink are connected.

5. A video relayer device comprising:

a processing unit;

a memory to store a calculation result and second key information, the calculation result being produced by an external video content sink based upon first key information, and the first key information being associated with a first key held by an external video content source; and

the processing unit being configured to include,

a key information transfer section to transfer first key information to the sink upon receiving the first key information from the source, and

a timer pausing section to control the timer of the source to pause upon receiving the first key information from the source;

the processing unit being operable to receive second key information and a calculation result from the sink and store the same, respectively, in the memory; and

the processing unit being further configured to include,

a timer resuming section to control the timer of the source to resume when the second key information and the calculation result have been stored, respectively, in the memory.

6. The video relayer device according to claim 5,

wherein upon receiving the first key information from the source, the timer pausing section is further operable to notify the source that the source and the sink are not connected and to control the timer to pause by turning off a hot-plug signal, and

wherein, when the second key information and the calculation result have been stored in the memory, respectively, the timer resuming section is further operable to notify the source that the source and the sink are connected and to control the timer to resume by transmitting a hot-plug signal.