US3814847A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Television signal processing device
Assignee: Thales SA
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Filing: 1971-12-27
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Granted: 1974-06-04
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Expires: 1991-12-27
Abstract
Abstract In order to obtain a contour corrected image signal, from which the noise is eliminated in the transition-free zones, a contour signal, derived from a blurred image signal (translating an image which is blurred as compared with that which is translated by the signal which is being processed, but from which the noise has been substantially eliminated) is added, with a suitable gain, to the blurred image signal.
Inventors
- 👤 M Longuet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 06:45
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/14; H04N5/142
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
140 words
A device for processing a television input signal, S(t), said device comprising a delaying and adding circuit for deriving from said input signal a further signal representative of the same image as said input signal but with a lower horizontal and vertical definition; a second circuit for delivering a contour signal, said second circuit having an output and comprising a subtracting device having first and second inputs respectively supplied with said input signal and with said further signal and an output, said output of said second circuit being coupled to said output of said subtracting device; and an adder having a first input coupled to said ouptut of said second circuit for receiving said contour signal, a second input coupled to said delaying and adding circuit for receiving said further signal, and an output for delivering a contour corrected signal.
Claim 2
Independent Claim
140 words
A device for processing a television input signal, S(t), said device comprising a delaying and adding circuit for deriving from said input signal a further signal representative of the same image as said input signal but with a lower horizontal and vertical definition; a second circuit for delivering a contour signal, said second circuit having an output and comprising a subtracting device having first and second inputs respectively supplied with said input signal and with said further signal and an output, said output of said second circuit being coupled to said output of said subtracting device; and an adder having a first input coupled to said ouptut of said second circuit for receiving said contour signal, a second input coupled to said delaying and adding circuit for receiving said further signal, and an output for delivering a contour corrected signal.
Claim 3
Dependent Claim
85 words
A device as claimed in claim 1, wherein said delaying and adding circuit is a circuit for delivering a signal Z(t) which is a linear function of the nine signals S(t-2H-2 theta ), S(t-2-theta ), S(t-2H), S(t-H-2 theta ), S(t-H- theta ), S(t-H), S(t-2 theta ), S(t- theta ) and S(t), where H is the line period and theta a duration which is small compared with H and wherein said first input of said subtracting device receives said input signal delayed by H+ theta .
Claim 4
Dependent Claim
18 words
A device as claimed in claim 2, wherein said linear function is the mean of said nine signals.
Claim 5
Dependent Claim
110 words
A device as claimed in claim 3 wherein said second circuit further comprises a double clipper which clips its input signal to either side of its mean value, and a filter, the two being supplied in parallel by said output of said subtracting device, and a further device, having an output, and two inputs respectively coupled to said double clipper and to said filter, for producing a contour signal of the form pC1+(1-p)C2 where C1 is the output signal from said filter, C2 that from said base clipper and p a parameter variable between zero and 1 said output of said further device forming said output of said second circuit.
Claim 6
Dependent Claim
32 words
A device as claimed in claim 4, wherein said second circuit further comprises two base-clippers through which said delayed input signal and said further signal are respectively applied to said subtracting device.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-03 | 1977-12-03 | 1978-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-03 | 1981-12-03 | 1982-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-03 | 1985-12-03 | 1986-06-04 | $7700.00 | Window Closed / Lapsed |