Patent US4254434A successfully refreshed from Google Patents.
US4254434A
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Video signal mixing system
Assignee: Sony Corp
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Filing: 1979-11-19
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Granted: 1981-03-03
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Expires: 1999-11-19
Abstract
Abstract A video signal mixing system in which a blanking portion is formed at a predetermined interval in a first video signal by a blanking signal, and a second video signal is inserted into the formed blanking portion of the first video signal, and in which a pedestal level of the first video signal, is detected and held, and the blanking level of the blanking portion is clamped at the held pedestal level of the first video signal with the application of the blanking signal.
Inventors
- 👤 Toshio Suzuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:39
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/222; H04N5/262; H04N5/265; H04N5/44; H04N5/445; H04N5/45
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
80 words
A method for operating a video signal mixing system, comprising: forming a blanking portion at a predetermined interval in a first video signal by a blanking signal; detecting and holding a pedestal level of said first video signal and clamping a blanking level of said blanking portion at the held pedestal level of said first video signal with the application of said blanking signal; and inserting a second video signal into the formed blanking portion of the first video signal.
Claim 2
Independent Claim
80 words
A method for operating a video signal mixing system, comprising: forming a blanking portion at a predetermined interval in a first video signal by a blanking signal; detecting and holding a pedestal level of said first video signal and clamping a blanking level of said blanking portion at the held pedestal level of said first video signal with the application of said blanking signal; and inserting a second video signal into the formed blanking portion of the first video signal.
Claim 3
Dependent Claim
42 words
A method for operating a video signal mixing system according to claim 1 including the steps of sampling said second video signal by said blanking signal, and inserting the sampled second video signal into said blanking portion of the first video signal.
Claim 4
Dependent Claim
27 words
A method for operating a video signal mixing system according to claim 2 including the step of subtracting a DC voltage from said sampled second video signal.
Claim 5
Dependent Claim
34 words
A method for operating a video signal mixing system according to claim 3 including the step of providing a level of said DC voltage equal to the pedestal level of said second video signal.
Claim 6
Dependent Claim
50 words
A method for operating a video signal mixing system according to claim 1 including the step of subtracting a DC voltage from said second video signal, sampling said second video signal by said blanking signal, and inserting the sampled video signal into said blanking portion of the first video signal.
Claim 7
Dependent Claim
34 words
A method for operating a video signal mixing system according to claim 5 including the step of providing a level of said DC voltage equal to the pedestal level of said second video signal.
Claim 8
Dependent Claim
84 words
A video signal mixing system, comprising: blanking means for forming a blanking portion at a predetermined interval in a first video signal by a blanking signal; clamping means for detecting and holding a pedestal level of said first video signal and clamping a blanking level of said blanking portion at the held pedestal level of said first video signal with the application of said blanking signal; and means for inserting a second video signal into the formed blanking portion of the first video signal.
Claim 9
Dependent Claim
84 words
A video signal mixing system, comprising: blanking means for forming a blanking portion at a predetermined interval in a first video signal by a blanking signal; clamping means for detecting and holding a pedestal level of said first video signal and clamping a blanking level of said blanking portion at the held pedestal level of said first video signal with the application of said blanking signal; and means for inserting a second video signal into the formed blanking portion of the first video signal.
References Cited (Backward Citations)
US3558815A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-03-02 | 1984-09-01 | 1985-03-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-02 | 1988-09-01 | 1989-03-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-02 | 1992-09-01 | 1993-03-03 | $7700.00 | Window Closed / Lapsed |