Patent JPS5339874A successfully refreshed from Google Patents.
US4769692A
Expired / Lapsed
US
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Method and apparatus for calibrating the phase of a video signal
Assignee: Grass Valley USA LLC
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Filing: 1987-03-27
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Granted: 1988-09-06
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Expires: 2007-03-27
Abstract
Abstract The color burst of a first video signal is brought into a desired phase relationship with the color burst of a second video signal by generating a first number which is representative of the phase relationship between the burst of the second video signal and a calibration reference signal and generating a second number which is representative of the phase relationship between the burst of the first video signal and the calibration reference signal. The second number is compared with the first number, and the phase of the burst of the first video signal is adjusted automatically in a manner such as to achieve a predetermined relationship between the second number and the first number.
Inventors
- 👤 Grant McFetridge
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:42
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/44; H04N9/475
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
140 words
A method of calibrating the phase of the burst of a first video signal to bring it into a desired phase relationship with the burst of a second video signal, comprising the following steps: (a) generating a first number representative of a phase difference between the burst of the first video signal and a calibration reference signal, (b) generating a second number representative of a phase difference between the burst of the second video signal and the calibration reference signal, (c) comparing the second number with the first number to obtain a phase difference number, and (d) automatically adjusting the phase of the burst of the first video signal in response to the phase difference number to change the first number so as to make the phase difference number equal to a predetermined value representative of the desired phase relationship.
Claim 2
Independent Claim
140 words
A method of calibrating the phase of the burst of a first video signal to bring it into a desired phase relationship with the burst of a second video signal, comprising the following steps: (a) generating a first number representative of a phase difference between the burst of the first video signal and a calibration reference signal, (b) generating a second number representative of a phase difference between the burst of the second video signal and the calibration reference signal, (c) comparing the second number with the first number to obtain a phase difference number, and (d) automatically adjusting the phase of the burst of the first video signal in response to the phase difference number to change the first number so as to make the phase difference number equal to a predetermined value representative of the desired phase relationship.
Claim 3
Dependent Claim
32 words
A method according to claim 1, wherein step (a) is performed after step (b) and step (b) comprises the operation of storing the second number until the first number has been generated.
Claim 4
Dependent Claim
35 words
A method according to claim 1, comprising adjusting the phase of the burst of the first video signal in a manner such as to achieve substantial equality between the first number and the second number.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-09-06 | 1992-03-07 | 1992-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-06 | 1996-03-07 | 1996-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-06 | 2000-03-07 | 2000-09-06 | $7700.00 | Window Closed / Lapsed |