Method for video synchronization in video distribution systems

• US 9,973,795 B2
• Filed: 08/27/2015
• Issued: 05/15/2018
• Est. Priority Date: 08/27/2014
• Status: Active Grant

• Current Assignee: Clearone Incorporated
• Original Assignee: Clearone Incorporated
• Inventors: Cunningham, John P., Zimmerman, Donald Shelly
• Primary Examiner(s): Kumar, Pankaj
• Assistant Examiner(s): Riaz, Sahar A
• Application Number:
  US14/837,321
• Publication Number:
  US 20160066000A1
• Time in Patent Office: 992 Days
• Field of Search: 725 90
• CPC Class Codes: H04N 21/231 Content storage operation, e.g. caching movies for short term storage, replicating data over plural servers, prioritizing data for deletion
• CPC Class Codes: H04N 21/234381 by altering the temporal resolution, e.g. decreasing the frame rate by frame skipping
• 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 21/44004 involving video buffer management, e.g. video decoder buffer or video display buffer

Abstract

This disclosure describes a method for video synchronization in video distribution systems that includes a system that re-synchronizes the video playback of a video synchronization device with that of a host device after any change by the host, interruption within the host, or interruption of data flow between a video source device and a video display device.

Claims

1. A video synchronization system that re-synchronizes the video playback of a video synchronization device with that of a host device after any change by the host, interruption within the host, or interruption of video data signals between a video source device and a video display device, comprising:

a video data signal generated by the video source device;

a video display device that generates an extended display identification data;

a video synchronization device with a video synchronization device processor and a video synchronization device memory, said video synchronization device is in communication with sad video display device, said video synchronization device generates video parameters;

a host device with a host processor and a host memory, said host device is coupled to said video synchronization device, said host device generates and stores in said host memory a predefined relationship that is further based on a predefined frame size based on said extended display identification data and said video parameters, said host device receives said video data signal from the video source device and stores said video data signal in said host memory, said video data signal further comprises video subframes at a first frame rate;

said video synchronization device is configured to execute the following steps;

receive one or more video subframes from said video data signal received from said host device, said video subframes in said predefined relationship to said predefined frame size;

transmit the video data signal to said video display device;

request said host device for a next video subframe having said predefined frame size;

set a condition flag in said video synchronization device memory that can be read by said host device if the next video subframe is not available at the required time to be transmitted to said video display device in order to notify said host device that an underrun has occurred,

reset the video playback pointer of said video synchronization device to row one, column one of a new frame; and

continuously send the previously received video data signal to said video display device using a “

frame repeat”

function and wait indefinitely for said host device to provide new data representing the pixel at the first row and first column of a new video frame once the flow of said video data into said host device has resumed;

wherein said video synchronization device may be configured to remove existing video transmission settings related to or embedded in the last outputted or transmitted video frame and request a new frame from said host device upon detecting a loss of synchronization between said video display device and said host device where the removal of the last transmitted frame data, represented by the existing video transmission settings, prevents any overlap between the last transmitted video frame and a new frame to be transmitted.

13. The claim of claim 1 further comprising said video synchronization device flushing the existing data in said video synchronization device memory, resets its video playback pointer to row one column one of a new frame, and notifies said host device that said video synchronization device is ready to begin video playback if it is notified by said host that the frame rate of incoming video must change.

2. A video synchronization system that re-synchronizes the video playback of a video synchronization device with that of a host device after any change by the host, interruption within the host, or interruption of video data signals between a video source device and a video display device, comprising:

a video data signal generated by the video source device;

a video display device that generates an extended display identification data;

a video synchronization device with a video synchronization device processor and a video synchronization device memory, said video synchronization device is in communication with said video display device, said video synchronization device generates video parameters;

a host device with a host processor and a host memory, said host device is coupled to said video synchronization device, said host device generates and stores in said host memory a predefined relationship that is further based on a predefined frame size based on said extended display identification data and said video parameters, said host device receives said video data signal from the video source device and stores said video data signal in said host memory, said video data signal further comprises video subframes at a first frame rate;

said video synchronization device is configured to execute the following steps;

receive one or more video subframes from said video data signal received from said host device, said video subframes in said predefined relationship to said predefined frame size;

transmit the video data signal to said video display device;

request said host device for a next video subframe having said predefined frame size;

set a condition flag in said video synchronization device memory that can be read by said host device if the next video subframe is not available at the required time to be transmitted to said video display device in order to notify said host device that an underrun has occurred,

reset the video playback pointer of said video synchronization device to row one, column one of a new frame; and

continuously send the previously received video data signal to said video display device using a “

frame repeat”

function and wait indefinitely for said host device to provide new data representing the pixel at the first row and first column of a new video frame once the flow of said video data into said host device has resumed;

wherein said video synchronization device uses said extended display identification data to dynamically preset or update the video clock frequency at which it outputs said video data signal.

14. The claim of claim 2 further comprising said video synchronization device flushing the existing data in said video synchronization device memory, resets its video playback pointer to row one column one of a new frame, and notifies said host device that said video synchronization device is ready to begin video playback if it is notified by said host that the frame rate of incoming video must change.

3. A video synchronization system that re-synchronizes the video playback of a video synchronization device with that of a host device after any change by the host, interruption within the host, or interruption of video data signals between a video source device and a video display device, comprising:

a video data signal generated by the video source device;

a video display device that generates an extended display identification data;

a video synchronization device with a video synchronization device processor and a video synchronization device memory, said video synchronization device is in communication with said video display device, said video synchronization device generates video parameters;

a host device with a host processor and a host memory, said host device is coupled to said video synchronization device, said host device generates and stores in said host memory a predefined relationship that is further based on a predefined frame size based on said extended display identification data and said video parameters, said host device receives said video data signal from the video source device and stores said video data signal in said host memory, said video data signal further comprises video subframes at a first frame rate;

said video synchronization device is configured to execute the following steps;

receive one or more video subframes from said video data signal received from said host device, said video subframes in said predefined relationship to said predefined frame size;

transmit the video data signal to said video display device;

request said host device for a next video subframe having said predefined frame size;

set a condition flag in said video synchronization device memory that can be read by said host device if the next video subframe is not available at the required time to be transmitted to said video display device in order to notify said host device that an underrun has occurred,

reset the video playback pointer of said video synchronization device to row one, column one of a new frame; and

continuously send the previously received video data signal to said video display device using a “

frame repeat”

function and wait indefinitely for said host device to provide new data representing the pixel at the first row and first column of a new video frame once the flow of said video data into said host device has resumed;

wherein said host device uses said extended display identification data along with information on the frequency with which said video synchronization device is requesting new video data in comparison with the rate at which the said host device is receiving video data from the video source device to dynamically adjust the video transmission settings in order to adjust the frame rate of said video synchronization device.

15. The claim of claim 3 further comprising said video synchronization device flushing the existing data in said video synchronization device memory, resets its video playback pointer to row one column one of a new frame, and notifies said host device that said video synchronization device is ready to begin video playback if it is notified by said host that the frame rate of incoming video must change.

4. A method to manufacture a video synchronization system that re-synchronizes the video playback of a video synchronization device with that of a host device after any change by the host, interruption within the host, or interruption of video data signals between a video source device and a video display device, comprising:

providing a video data signal generated by the video source device;

providing a video display device that generates an extended display identification data;

coupling a video synchronization device with a video synchronization device processor and a video synchronization device memory said video display device, said video synchronization device generates video parameters;

coupling a host device with a host processor and a host memory to said video synchronization device, said host device generates and stores in said host memory a predefined relationship that is further based on a predefined frame size based on said extended display identification data and said video parameters, said host device receives said video data signal from the video source device and stores said video data signal in said host memory, said video data signal further comprises video subframes at a first frame rate;

said video synchronization device is configured to execute the following steps;

receive one or more video subframes from said video data signal received from said host device, said video subframes in said predefined relationship to said predefined frame size;

transmit the video data signal to said video display device;

request said host device for a next video subframe having said predefined frame size;

set a condition flag in said video synchronization device memory that can be read by said host device if the next video subframe is not available at the required time to be transmitted to said video display device in order to notify said host device that an underrun has occurred,

reset the video playback pointer of said video synchronization device to row one, column one of a new frame; and

continuously send the previously received video data signal to said video display device using a “

frame repeat”

function and wait indefinitely for said host device to provide new data representing the pixel at the first row and first column of a new video frame once the flow of said video data into said host device has resumed;

wherein said video synchronization device may be configured to remove existing video transmission settings related to or embedded in the last outputted or transmitted video frame and request a new frame from said host device upon detecting a loss of synchronization between said video display device and said host device where the removal of the last transmitted frame data, represented by the existing video transmission settings, prevents any overlap between the last transmitted video frame and a new frame to be transmitted.

16. The claim of claim 4 further comprising said video synchronization device flushing the existing data in said video synchronization device memory, resets its video playback pointer to row one column one of a new frame, and notifies said host device that said video synchronization device is ready to begin video playback if it is notified by said host that the frame rate of incoming video must change.

5. A method to manufacture a video synchronization system that re-synchronizes the video playback of a video synchronization device with that of a host device after any change by the host, interruption within the host, or interruption of video data signals between a video source device and a video display device, comprising:

providing a video data signal generated by the video source device;

providing a video display device that generates an extended display identification data;

coupling a video synchronization device with a video synchronization device processor and a video synchronization device memory said video display device, said video synchronization device generates video parameters;

coupling a host device with a host processor and a host memory to said video synchronization device, said host device generates and stores in said host memory a predefined relationship that is further based on a predefined frame size based on said extended display identification data and said video parameters, said host device receives said video data signal from the video source device and stores said video data signal in said host memory, said video data signal further comprises video subframes at a first frame rate;

said video synchronization device is configured to execute the following steps;

receive one or more video subframes from said video data signal received from said host device, said video subframes in said predefined relationship to said predefined frame size;

transmit the video data signal to said video display device;

request said host device for a next video subframe having said predefined frame size;

set a condition flag in said video synchronization device memory that can be read by said host device if the next video subframe is not available at the required time to be transmitted to said video display device in order to notify said host device that an underrun has occurred,

reset the video playback pointer of said video synchronization device to row one, column one of a new frame; and

continuously send the previously received video data signal to said video display device using a “

frame repeat”

function and wait indefinitely for said host device to provide new data representing the pixel at the first row and first column of a new video frame once the flow of said video data into said host device has resumed;

wherein said video synchronization device uses said extended display identification data to dynamically preset or update the video clock frequency at which it outputs said video data signal.

17. The claim of claim 5 further comprising said video synchronization device flushing the existing data in said video synchronization device memory, resets its video playback pointer to row one column one of a new frame, and notifies said host device that said video synchronization device is ready to begin video playback if it is notified by said host that the frame rate of incoming video must change.

6. A method to manufacture a video synchronization system that re-synchronizes the video playback of a video synchronization device with that of a host device after any change by the host, interruption within the host, or interruption of video data signals between a video source device and a video display device, comprising:

providing a video data signal generated by the video source device;

providing a video display device that generates an extended display identification data;

coupling a video synchronization device with a video synchronization device processor and a video synchronization device memory said video display device, said video synchronization device generates video parameters;

coupling a host device with a host processor and a host memory to said video synchronization device, said host device generates and stores in said host memory a predefined relationship that is further based on a predefined frame size based on said extended display identification data and said video parameters, said host device receives said video data signal from the video source device and stores said video data signal in said host memory, said video data signal further comprises video subframes at a first frame rate;

said video synchronization device is configured to execute the following steps;

receive one or more video subframes from said video data signal received from said host device, said video subframes in said predefined relationship to said predefined frame size;

transmit the video data signal to said video display device;

request said host device for a next video subframe having said predefined frame size;

set a condition flag in said video synchronization device memory that can be read by said host device if the next video subframe is not available at the required time to be transmitted to said video display device in order to notify said host device that an underrun has occurred,

reset the video playback pointer of said video synchronization device to row one, column one of a new frame; and

continuously send the previously received video data signal to said video display device using a “

frame repeat”

function and wait indefinitely for said host device to provide new data representing the pixel at the first row and first column of a new video frame once the flow of said video data into said host device has resumed;

wherein said host device uses said extended display identification data along with information on the frequency with which said video synchronization device is requesting new video data in comparison with the rate at which the said host device is receiving video data from the video source device to dynamically adjust the video transmission settings in order to adjust the frame rate of said video synchronization device.

18. The claim of claim 6 further comprising said video synchronization device flushing the existing data in said video synchronization device memory, resets its video playback pointer to row one column one of a new frame, and notifies said host device that said video synchronization device is ready to begin video playback if it is notified by said host that the frame rate of incoming video must change.

7. A method to use a video synchronization system that re-synchronizes the video playback of a video synchronization device with that of a host device after any change by the host, interruption within the host, or interruption of video data signals between a video source device and a video display device, comprising:

receiving a video data signal generated by the video source device;

generating an extended display identification data using a video display device;

communicating between a video synchronization device with a video synchronization device processor and a video synchronization device memory and said video display device, said video synchronization device generates video parameters;

communicating between a host device with a host processor and a host memory, and said video synchronization device, said host device generates and stores in said host memory a predefined relationship that is further based on a predefined frame size based on said extended display identification data and said video parameters, said host device receives said video data signal from the video source device and stores said video data signal in said host memory, said video data signal further comprises video subframes at a first frame rate;

said video synchronization device is configured to execute the following steps;

receive one or more video subframes from said video data signal received from said host device, said video subframes in said predefined relationship to said predefined frame size;

transmit the video data signal to said video display device;

request said host device for a next video subframe having said predefined frame size;

set a condition flag in said video synchronization device memory that can be read by said host device if the next video subframe is not available at the required time to be transmitted to said video display device in order to notify said host device that an underrun has occurred,

reset the video playback pointer of said video synchronization device to row one, column one of a new frame; and

continuously send the previously received video data signal to said video display device using a “

frame repeat”

function and wait indefinitely for said host device to provide new data representing the pixel at the first row and first column of a new video frame once the flow of said video data into said host device has resumed;

wherein said video synchronization device may be configured to remove existing video transmission settings related to or embedded in the last outputted or transmitted video frame and request a new frame from said host device upon detecting a loss of synchronization between said video display device and said host device where the removal of the last transmitted frame data, represented by the existing video transmission settings, prevents any overlap between the last transmitted video frame and a new frame to be transmitted.

19. The claim of claim 7 further comprising said video synchronization device flushing the existing data in said video synchronization device memory, resets its video playback pointer to row one column one of a new frame, and notifies said host device that said video synchronization device is ready to begin video playback if it is notified by said host that the frame rate of incoming video must change.

8. A method to use a video synchronization system that re-synchronizes the video playback of a video synchronization device with that of a host device after any change by the host, interruption within the host, or interruption of video data signals between a video source device and a video display device, comprising:

receiving a video data signal generated by the video source device;

generating an extended display identification data using a video display device;

communicating between a video synchronization device with a video synchronization device processor and a video synchronization device memory and said video display device, said video synchronization device generates video parameters;

communicating between a host device with a host processor and a host memory, and said video synchronization device, said host device generates and stores in said host memory a predefined relationship that is further based on a predefined frame size based on said extended display identification data and said video parameters, said host device receives said video data signal from the video source device and stores said video data signal in said host memory, said video data signal further comprises video subframes at a first frame rate;

said video synchronization device is configured to execute the following steps;

receive one or more video subframes from said video data signal received from said host device, said video subframes in said predefined relationship to said predefined frame size;

transmit the video data signal to said video display device;

request said host device for a next video subframe having said predefined frame size;

set a condition flag in said video synchronization device memory that can be read by said host device if the next video subframe is not available at the required time to be transmitted to said video display device in order to notify said host device that an underrun has occurred,

reset the video playback pointer of said video synchronization device to row one, column one of a new frame; and

continuously send the previously received video data signal to said video display device using a “

frame repeat”

function and wait indefinitely for said host device to provide new data representing the pixel at the first row and first column of a new video frame once the flow of said video data into said host device has resumed;

wherein said video synchronization device uses said extended display identification data to dynamically preset or update the video clock frequency at which it outputs said video data signal.

20. The claim of claim 8 further comprising said video synchronization device flushing the existing data in said video synchronization device memory, resets its video playback pointer to row one column one of a new frame, and notifies said host device that said video synchronization device is ready to begin video playback if it is notified by said host that the frame rate of incoming video must change.

9. A method to use a video synchronization system that re-synchronizes the video playback of a video synchronization device with that of a host device after any change by the host, interruption within the host, or interruption of video data signals between a video source device and a video display device, comprising:

receiving a video data signal generated by the video source device;

generating an extended display identification data using a video display device;

communicating between a video synchronization device with a video synchronization device processor and a video synchronization device memory and said video display device, said video synchronization device generates video parameters;

communicating between a host device with a host processor and a host memory, and said video synchronization device, said host device generates and stores in said host memory a predefined relationship that is further based on a predefined frame size based on said extended display identification data and said video parameters, said host device receives said video data signal from the video source device and stores said video data signal in said host memory, said video data signal further comprises video subframes at a first frame rate;

said video synchronization device is configured to execute the following steps;

receive one or more video subframes from said video data signal received from said host device, said video subframes in said predefined relationship to said predefined frame size;

transmit the video data signal to said video display device;

request said host device for a next video subframe having said predefined frame size;

set a condition flag in said video synchronization device memory that can be read by said host device if the next video subframe is not available at the required time to be transmitted to said video display device in order to notify said host device that an underrun has occurred,

reset the video playback pointer of said video synchronization device to row one, column one of a new frame; and

continuously send the previously received video data signal to said video display device using a “

frame repeat”

function and wait indefinitely for said host device to provide new data representing the pixel at the first row and first column of a new video frame once the flow of said video data into said host device has resumed;

wherein said host device uses said extended display identification data along with information on the frequency with which said video synchronization device is requesting new video data in comparison with the rate at which the said host device is receiving video data from the video source device to dynamically adjust the video transmission settings in order to adjust the frame rate of said video synchronization device.

21. The claim of claim 9 further comprising said video synchronization device flushing the existing data in said video synchronization device memory, resets its video playback pointer to row one column one of a new frame, and notifies said host device that said video synchronization device is ready to begin video playback if it is notified by said host that the frame rate of incoming video must change.

10. A non-transitory program storage device readable by a computing device that tangibly embodies a program of instructions executable by the computing device to perform a method to use a video synchronization system that re-synchronizes the video playback of a video synchronization device with that of a host device after any change by the host, interruption within the host, or interruption of video data signals between a video source device and a video display device, comprising:

receiving a video data signal generated by the video source device;

generating an extended display identification data using a video display device;

communicating between a video synchronization device with a video synchronization device processor and a video synchronization device memory and said video display device, said video synchronization device generates video parameters;

communicating between a host device with a host processor and a host memory, and said video synchronization device, said host device generates and stores in said host memory a predefined relationship that is further based on a predefined frame size based on said extended display identification data and said video parameters, said host device receives said video data signal from the video source device and stores said video data signal in said host memory, said video data signal further comprises video subframes at a first frame rate;

said video synchronization device is configured to execute the following steps;

receive one or more video subframes from said video data signal received from said host device, said video subframes in said predefined relationship to said predefined frame size;

transmit the video data signal to said video display device;

request said host device for a next video subframe having said predefined frame size;

set a condition flag in said video synchronization device memory that can be read by said host device if the next video subframe is not available at the required time to be transmitted to said video display device in order to notify said host device that an underrun has occurred,

reset the video playback pointer of said video synchronization device to row one, column one of a new frame; and

continuously send the previously received video data signal to said video display device using a “

frame repeat”

function and wait indefinitely for said host device to provide new data representing the pixel at the first row and first column of a new video frame once the flow of said video data into said host device has resumed;

wherein said video synchronization device may be configured to remove existing video transmission settings related to or embedded in the last outputted or transmitted video frame and request a new frame from said host device upon detecting a loss of synchronization between said video display device and said host device where the removal of the last transmitted frame data, represented by the existing video transmission settings, prevents any overlap between the last transmitted video frame and a new frame to be transmitted.

22. The claim of claim 10 further comprising said video synchronization device flushing the existing data in said video synchronization device memory, resets its video playback pointer to row one column one of a new frame, and notifies said host device that said video synchronization device is ready to begin video playback if it is notified by said host that the frame rate of incoming video must change.

11. A non-transitory program storage device readable by a computing device that tangibly embodies a program of instructions executable by the computing device to perform a method to use a video synchronization system that re-synchronizes the video playback of a video synchronization device with that of a host device after any change by the host, interruption within the host, or interruption of video data signals between a video source device and a video display device, comprising:

receiving a video data signal generated by the video source device;

generating an extended display identification data using a video display device;

communicating between a video synchronization device with a video synchronization device processor and a video synchronization device memory and said video display device, said video synchronization device generates video parameters;

communicating between a host device with a host processor and a host memory, and said video synchronization device, said host device generates and stores in said host memory a predefined relationship that is further based on a predefined frame size based on said extended display identification data and said video parameters, said host device receives said video data signal from the video source device and stores said video data signal in said host memory, said video data signal further comprises video subframes at a first frame rate;

said video synchronization device is configured to execute the following steps;

receive one or more video subframes from said video data signal received from said host device, said video subframes in said predefined relationship to said predefined frame size;

transmit the video data signal to said video display device;

request said host device for a next video subframe having said predefined frame size;

set a condition flag in said video synchronization device memory that can be read by said host device if the next video subframe is not available at the required time to be transmitted to said video display device in order to notify said host device that an underrun has occurred,

reset the video playback pointer of said video synchronization device to row one, column one of a new frame; and

continuously send the previously received video data signal to said video display device using a “

frame repeat”

function and wait indefinitely for said host device to provide new data representing the pixel at the first row and first column of a new video frame once the flow of said video data into said host device has resumed;

wherein said video synchronization device uses said extended display identification data to dynamically preset or update the video clock frequency at which it outputs said video data signal.

23. The claim of claim 11 further comprising said video synchronization device flushing the existing data in said video synchronization device memory, resets its video playback pointer to row one column one of a new frame, and notifies said host device that said video synchronization device is ready to begin video playback if it is notified by said host that the frame rate of incoming video must change.

12. A non-transitory program storage device readable by a computing device that tangibly embodies a program of instructions executable by the computing device to perform a method to use a video synchronization system that re-synchronizes the video playback of a video synchronization device with that of a host device after any change by the host, interruption within the host, or interruption of video data signals between a video source device and a video display device, comprising:

receiving a video data signal generated by the video source device;

generating an extended display identification data using a video display device;

communicating between a video synchronization device with a video synchronization device processor and a video synchronization device memory and said video display device, said video synchronization device generates video parameters;

communicating between a host device with a host processor and a host memory, and said video synchronization device, said host device generates and stores in said host memory a predefined relationship that is further based on a predefined frame size based on said extended display identification data and said video parameters, said host device receives said video data signal from the video source device and stores said video data signal in said host memory, said video data signal further comprises video subframes at a first frame rate;

said video synchronization device is configured to execute the following steps;

receive one or more video subframes from said video data signal received from said host device, said video subframes in said predefined relationship to said predefined frame size;

transmit the video data signal to said video display device;

request said host device for a next video subframe having said predefined frame size;

set a condition flag in said video synchronization device memory that can be read by said host device if the next video subframe is not available at the required time to be transmitted to said video display device in order to notify said host device that an underrun has occurred,

reset the video playback pointer of said video synchronization device to row one, column one of a new frame; and

continuously send the previously received video data signal to said video display device using a “

frame repeat”

function and wait indefinitely for said host device to provide new data representing the pixel at the first row and first column of a new video frame once the flow of said video data into said host device has resumed;

wherein said host device uses said extended display identification data along with information on the frequency with which said video synchronization device is requesting new video data in comparison with the rate at which the said host device is receiving video data from the video source device to dynamically adjust the video transmission settings in order to adjust the frame rate of said video synchronization device.

24. The claim of claim 12 further comprising said video synchronization device flushing the existing data in said video synchronization device memory, resets its video playback pointer to row one column one of a new frame, and notifies said host device that said video synchronization device is ready to begin video playback if it is notified by said host that the frame rate of incoming video must change.