System and method for generating linear time code data

• US 20090067561A1
• Filed: 09/05/2008
• Published: 03/12/2009
• Est. Priority Date: 09/07/2007
• Status: Active Grant

• Current Assignee: Gvbb Holdings SARL (Vislink Technologies, Inc.)
• Original Assignee: Gvbb Holdings SARL (Vislink Technologies, Inc.)
• Inventors: Kuppens, Chris
• Granted Patent: US 8,290,106 B2
• Time in Patent Office: Days
• US Class Current: 375/362
• CPC Class Codes: G11B 20/10222 clock-related aspects, e.g. phase or frequency adjustment or bit synchronisation dedicated sync patterns in the modulation code G11B20/1403
• CPC Class Codes: G11B 2020/10537 Audio or video recording
• CPC Class Codes: H04N 5/77 between a recording apparatus and a television camera

Abstract

The present invention relates to a linear time code (LTC) generator that is adapted to generate LTC data. The LTC generator comprises a rising edge detector that is adapted to detect a frame sync input corresponding to a beginning of a frame time of video data and to generate a first synchronization signal corresponding to the frame sync input and a frame length measurement block that is adapted to count a number of clock cycles in the frame time. The LTC generator further comprises a bit rate calculator that is adapted to determine a bit rate of the frame time based on the number of clock cycles in the frame time and a bit rate counter block that is adapted to generate a second synchronization signal corresponding to the bit rate. Finally, the LTC generator comprises an output device that is adapted to insert a first data bit of the LTC data into a digital bit stream according to the first synchronization signal and to insert subsequent data bits of the LTC data (208) into the digital bit stream according to the second synchronization signal

Claims

1. A linear time code (LTC) generator that is adapted to generate LTC data, the LTC generator comprising:

a detector that is adapted to detect a frame sync input corresponding to a beginning of a frame time of video data and to generate a first synchronization signal corresponding to the frame sync input;

a frame length determination block that is adapted to determine a frame length of the video data in clock cycles by counting a number of clock cycles in the frame time;

a bit rate counter block that is adapted to generate a second synchronization signal corresponding to a bit rate that is determined from the frame length in clock cycles; and

an output device that is adapted to insert a first data bit of the LTC data into a digital bit stream according to the first synchronization signal and to insert subsequent data bits of the LTC data into the digital bit stream according to the second synchronization signal, so that the application of the LTC data is not dependent on the frame length.

2. The linear time code generator according to claim 1, said output device being adapted to insert the LTC data across a single frame time if the frame of video data has a frame rate below a predetermined threshold.

3. The linear time code generator according to claim 1, said output device being adapted to insert the LTC data across two frame times if the frame of video data has a frame rate above a predetermined threshold.

4. The linear time code generator according to claim 1, said output device being adapted to store the LTC data in association with a corresponding frame of video data.

5. The linear time code generator according to claim 1, said bit rate being determined according to the formula

6. A method for applying linear time code (LTC) data to a digital bit stream, the method comprising the steps of:

counting a number of clock cycles in a frame time of video data;

determining a frame length of the video data in clock cycles by counting a number of clock cycles in the frame time;

inserting a first data bit of the linear time code data into the digital bit stream according to a first synchronization signal that corresponds to a start of the frame time; and

inserting subsequent data bits of the linear time code data into the digital bit stream according to a second synchronization signal that corresponds to a bit rate that is determined from the frame length in clock cycles, so that the application of the LTC data is not dependent on the frame length.

7. The method for applying linear time code data to a digital bit stream according to claim 6, comprising the step of:

inserting the LTC data across a single frame time if the frame of video data has a frame rate below a predetermined threshold.

8. The method for applying linear time code data to a digital bit stream according to claim 6, comprising the step of:

inserting the LTC data across two frame times if the frame of video data has a frame rate above a predetermined threshold.

9. The method for applying linear time code data to a digital bit stream according to claim 6, comprising the step of:

storing the LTC data in association with a corresponding frame of video data.

10. The method for applying linear time code data to a digital bit stream according to claim 6, wherein the bit rate is calculated according to the formula