US4977460A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Video signal reproducing apparatus having setup level elimination
Assignee: NEC Home Electronics Ltd
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Filing: 1988-04-28
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Granted: 1990-12-11
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Expires: 2008-04-28
Abstract
Abstract The present invention provides a video signal reproducing apparatus in which a set-up level of a video signal can be cancelled and the contrast of the signal maintained to obtain an accurately reproduced video signal. The present invention includes a set-up period indication circuit for generating a set-up period indication signal if a video signal with a set-up level exists, a subtraction circuit for subtracting a predetermined set-up level from the video signal containing the set-up level and an amplifier circuit for amplifying the subtracted video signal to a predetermined amplitude so that an accurately reproduced video signal is obtained.
Inventors
- 👤 Mitsuo Hirose
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 06:05
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/76; H04N5/91; H04N5/93; H04N5/931
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
73 words
An apparatus for producing an accurately reproduced video signal comprising: means for inputting a video signal; means for generating a set-up period indication signal if said video signal contains a set-up level during a set-up period; means for subtracting during said set-up period said set-up level from said video signal if said set-up period indication signal is present; and means for amplifying said subtracted video signal to obtain said accurately reproduced video signal.
Claim 2
Independent Claim
73 words
An apparatus for producing an accurately reproduced video signal comprising: means for inputting a video signal; means for generating a set-up period indication signal if said video signal contains a set-up level during a set-up period; means for subtracting during said set-up period said set-up level from said video signal if said set-up period indication signal is present; and means for amplifying said subtracted video signal to obtain said accurately reproduced video signal.
Claim 3
Dependent Claim
29 words
An apparatus according to claim 1 further including: means for detecting if a drop-out area exists in said video signal; and means for compensating said drop-out area by interpolation.
Claim 4
Dependent Claim
18 words
An apparatus according to claim 1 further including means for correcting time-base fluctuations present in said video signal.
Claim 5
Dependent Claim
40 words
An apparatus according to claim 1 wherein said set-up period indication signal generation means includes means for separating a synchronization signal from said video signal and wherein said synchronization signal is then used to generate said set-up period indication signal.
Claim 6
Dependent Claim
28 words
An apparatus according to claim 4 wherein said set-up period indication signal generation means and said amplifying means receive a set-up level on signal from an operation part.
Claim 7
Independent Claim
159 words
An apparatus for producing an accurately reproduced video signal comprising: means for inputting a first analog video signal; means for converting said first analog video signal to a digital signal; means for detecting if said first analog video signal contains a drop-out area; means for compensating said drop-out areas of said digital signal to obtain a compensated digital signal; means for generating a set-up period indication signal if said first analog video signal contains a set-up level during a set-up period; means for subtracting during said set-up period said set-up level from said compensated digital signal if said set-up period indication signal is present to obtain a subtracted digital signal; means for correcting time-based fluctuations in said subtracted digital signal to obtain a corrected digital signal; means for converting said corrected digital signal to a second analog video signal; and means for combining said second analog video signal with a character signal to obtain said accurately reproduced video signal.
Claim 8
Independent Claim
159 words
An apparatus for producing an accurately reproduced video signal comprising: means for inputting a first analog video signal; means for converting said first analog video signal to a digital signal; means for detecting if said first analog video signal contains a drop-out area; means for compensating said drop-out areas of said digital signal to obtain a compensated digital signal; means for generating a set-up period indication signal if said first analog video signal contains a set-up level during a set-up period; means for subtracting during said set-up period said set-up level from said compensated digital signal if said set-up period indication signal is present to obtain a subtracted digital signal; means for correcting time-based fluctuations in said subtracted digital signal to obtain a corrected digital signal; means for converting said corrected digital signal to a second analog video signal; and means for combining said second analog video signal with a character signal to obtain said accurately reproduced video signal.
Claim 9
Dependent Claim
66 words
An apparatus according to claim 6 wherein said digital to analog converter means and said set-up period indication signal generation means receives a set-up level on signal from an operation part if said first analog video signal contains said set-up level and wherein said digital to analog converter means includes means for amplifying said second analog video signal if it receives said set-up level on signal.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1993-12-10 | 1994-06-11 | 1994-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-10 | 1998-06-11 | 1998-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-10 | 2002-06-11 | 2002-12-11 | $7700.00 | Window Closed / Lapsed |