System providing standby operation of an auxiliary data decoder in a television receiver

• US 5,900,913 A
• Filed: 09/26/1995
• Issued: 05/04/1999
• Est. Priority Date: 09/26/1995
• Status: Expired due to Term

• Current Assignee: Thomson Consumer Electronics Incorporated (Vantiva SA)
• Original Assignee: Thomson Consumer Electronics Incorporated (Vantiva SA)
• Inventors: Tults, Juri
• Primary Examiner(s): Kostak, Victor R.
• Application Number:
  US08/533,951
• Time in Patent Office: 1,316 Days
• Field of Search: 348/468, 348/465, 348/461, 348/553, 348/569, 348/730, 348/706, 348/460
• US Class Current: 348/468
• CPC Class Codes: H04N 21/47 End-user applications
• CPC Class Codes: H04N 21/4884 for displaying subtitles
• CPC Class Codes: H04N 5/63 Generation or supply of power specially adapted for television receivers
• CPC Class Codes: H04N 7/035 Circuits for the digital non-picture data signal, e.g. for slicing of the data signal, for regeneration of the data-clock signal, for error detection or correction of the data signal
• CPC Class Codes: H04N 7/0882 for the transmission of character code signals, e.g. for teletext circuits for the digital non-picture data signal H04N7/035
• CPC Class Codes: H04N 7/0885 for the transmission of subtitles

Abstract

A decoder for decoding data from a data signal component of a television signal, such as closed caption data, decodes the data signal in response to a deflection signal during a normal mode of operation of a television receiver and in response to separated sync signal during a standby mode of operation of the television receiver.

Claims

1. A system comprising:

first means for producing a first timing signal in response to a synchronization signal component of a video signal;

second means for producing a second timing signal in response to said synchronization signal component of said video signal;

a decoder for decoding data included in a data signal component of said video signal in response to said first timing signal during a first mode of operation of said system and for decoding data included in said data signal component of said video signal in response to said second timing signal during a second mode of operation of said system; and

control means for disabling said first means during said second mode of operation, thereby preventing generation of said first timing signal by said first means during said second mode of operation.

2. The system of claim 1 wherein said first mode of operation comprises a normal mode of operation and said second mode comprises a standby mode of operation.

3. The system of claim 2 further comprising:

means for generating a control signal indicating whether said system is in said normal mode of operation or in said standby mode of operation; and

a switch responsive to said control signal for coupling said first timing signal to said decoder during said normal mode of operation and for coupling said second timing signal to said decoder during said standby mode of operation.

4. The system of claim 3 wherein said means for generating said first timing signal comprises a deflection signal generating unit and said first timing signal comprises a deflection signal for controlling a display device;

said means for generating said second timing signal comprises a sync separator and said second timing signal comprises a separated sync signal derived from said synchronization signal component of said video signal; and

said first and second timing signals indicate occurrence of a horizontal display interval.

5. The system of claim 3 wherein said means for generating said first timing signal comprises a deflection signal generating unit and said first timing signal comprises a deflection signal for controlling a display device;

said means for generating said second timing signal comprises a sync separator and said second timing signal comprises a separated sync signal derived from said synchronization signal component of said video signal; and

said first and second timing signals indicate occurrence of a vertical display interval.

6. The system of claim 4 wherein said decoder comprises means for establishing a duty cycle characteristic of said second timing signal for substantially preventing said decoder from responding to a portion of said synchronization signal component of said video signal.

7. The system of claim 6 wherein said second timing signal indicates a rate of occurrence of horizontal display intervals included in said synchronization signal component of said video signal;

and said duty cycle characteristic substantially prevents said decoder from responding to pulses occurring in said synchronization signal component at a rate greater than said rate of occurrence of said horizontal display intervals.

8. The system of claim 7 wherein said synchronization signal component of said video signal comprises a first group of pulses occurring at a horizontal display rate and a second group of pulses occurring at a vertical display rate;

said second group of pulses including a particular pulse exhibiting a pulse width greater than a pulse width of each of said pulses included in said first group of pulses; and

said apparatus further comprising means for detecting said particular pulse included in said second group of pulses.

9. The system of claim 8 wherein said data signal component represents one of closed caption data and XDS data and Starsight®

data.

10. A system comprising:

firstmeans for producing a first timing signal in response to a synchronization signal component of a video signal;

second means for producing a second timing signal in response to said first timing signal;

a decoder for decoding data included in a data signal component of said video signal in response to said first timing signal during a standby mode of operation of said system and for decoding data included in said data signal component of said video signal in response to said second timing signal during a normal mode of operation of said system; and

a source of operating power for supplying operating power to said second means during said first mode of operation and for removing said operating power from said second means during said second mode of operation.

11. The system of claim 10 further comprising:

means for generating a control signal indicating whether said system is in said normal mode of operation or in said standby mode of operation; and

a switch responsive to said control signal for coupling said first timing signal to said decoder during said normal mode of operation and for coupling said second timing signal to said decoder during said standby mode of operation.

12. The system of claim 11 wherein said means for generating said first timing signal comprises a sync separator and said first timing signal comprises a separated sync signal derived from said synchronization signal component of said video signal;

said means for generating said second timing signal comprises a deflection signal generating unit and said second timing signal comprises a deflection signal for controlling a display device; and

said first and second timing signals indicate occurrence of a horizontal display interval.

13. The system of claim 11 wherein said means for generating said first timing signal comprises a sync separator and said first timing signal comprises a separated sync signal derived from said synchronization signal component of said video signal;

said means for generating said second timing signal comprises a deflection signal generating unit and said second timing signal comprises a deflection signal for controlling a display device; and

said first and second timing signals indicate occurrence of a vertical display interval.

14. The system of claim 12 wherein said data signal component represents one of closed caption data and XDS data and Starsight®

data.

15. A system for processing a television signal to produce a video signal suitable for coupling to a display device for producing an image on said display device, said system comprising:

a deflection signal generating unit for generating vertical and horizontal deflection signals for controlling said display device during a normal mode of operation of said system;

a sync separator for generating a synchronization signal in response to a synchronization signal component of said television signal during a standby mode of operation of said system; and

a decoder for decoding a data signal component of said television signal in response to said vertical and horizontal deflection signals during said normal mode of operation and for decoding said data signal component of said television signal in response to said synchronization signal during said standby mode of operation.

16. The system of claim 15 wherein:

said decoder comprises a first counter responsive to a first control signal for generating a signal exhibiting a frequency substantially equal to a multiple of a horizontal display interval frequency of said video signal; and

a second counter responsive to a second control signal for counting horizontal line intervals of said video signal; and

wherein said system further comprises;

means for generating a third control signal indicating whether said system is in said normal mode of operation or in said standby mode of operation;

a first switch responsive to said third control signal for coupling said horizontal deflection signal to said first counter to provide said first control signal during said normal mode of operation and for coupling said synchronization signal to said first counter to provide said first control signal during said standby mode of operation; and

a second switch responsive to said third control signal for coupling said vertical deflection signal to said second counter to provide said second control signal during said standby mode of operation and for coupling said synchronization signal to said second counter to provide said second control signal during said standby mode of operation.