US3835243A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuitry for reducing effects of noise on color image
Assignee: Panasonic Holdings Corp
•
Filing: 1973-04-03
•
Granted: 1974-09-10
•
Expires: 1993-04-03
Abstract
Abstract A picture quality improving apparatus for a color television receiver. A signal detecting means for detecting a specific portion of the color-difference signal which reproduces a highsaturation color on the screen is connected to a nonlinear processing means coupled to the signal detecting means. The processing means reduces the amplitude of the color-difference signal in response to the output signal of the signal detecting means in order to eliminate noise disturbances, decreases in the sharpness and luminance errors appearing in a high-saturation color portion of a picture.
Inventors
- 👤 Y Nagaoka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 13:43
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/64; H04N9/68; H04N9/646
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
176 words
A picture quality improving apparatus for a color television receiver comprising signal detecting means having two input terminals, one of which is adapted to be connected to the source of the color-difference signal in the receiver to be supplied with the color-difference signal, the other of which is adapted to be connected to the source of the luminance signal in the receiver to be supplied with the luminance signal, said signal detecting means including detecting means for detecting a specific portion of said color-difference signal which reproduces a high-saturation color on the screen, and control signal producing means for producing a control signal when said specific portion is detected, and nonlinear processing means with two input terminals, one of which is adapted to be connected to the source of the color-difference signal to be supplied with said color-difference signal, the other of which is connected to said signal detecting means and is supplied with said control signal, said non-linear processing means being for reducing the amplitude of said color-difference signal in response to said control signal.
Claim 2
Dependent Claim
176 words
A picture quality improving apparatus for a color television receiver comprising signal detecting means having two input terminals, one of which is adapted to be connected to the source of the color-difference signal in the receiver to be supplied with the color-difference signal, the other of which is adapted to be connected to the source of the luminance signal in the receiver to be supplied with the luminance signal, said signal detecting means including detecting means for detecting a specific portion of said color-difference signal which reproduces a high-saturation color on the screen, and control signal producing means for producing a control signal when said specific portion is detected, and nonlinear processing means with two input terminals, one of which is adapted to be connected to the source of the color-difference signal to be supplied with said color-difference signal, the other of which is connected to said signal detecting means and is supplied with said control signal, said non-linear processing means being for reducing the amplitude of said color-difference signal in response to said control signal.
Claim 3
Dependent Claim
40 words
A picture quality improving apparatus as claimed in claim 1, wherein said detecting means of said signal detecting means is for detecting a specific portion of the amplitude of said color-difference signal which is larger than a predetermined threshold level.
Claim 4
Dependent Claim
66 words
A picture quality improving apparatus as claimed in claim 1, wherein said detecting means of said signal detecting means consists of a first means which produces a normalized color-difference signal by dividing said color-difference signal by said luminance signal and a second means coupled to said first means which detects the portion of said normalized color-difference signal having an amplitude larger than a predetermined threshold level.
Claim 5
Dependent Claim
64 words
A picture quality improving apparatus as claimed in claim 1, wherein said detecting means of said signal detecting means consists of a first means which produces a difference signal between said color-difference signal and said luminance signal and second means coupled to said first means which detects a specific portion of said difference signal which has an amplitude larger than a predetermined threshold level.
Claim 6
Dependent Claim
102 words
A picture quality improving apparatus as claimed in claim 1, wherein said detecting means of said signal detecting means is for detecting a specific portion of said luminance signal which has an amplitude larger than a predetermined threshold level, said nonlinear processing means having a different threshold level and comprises means for reducing the amplitude of said color-difference signal which exceeds said different threshold level when said control signal is not produced, and for preventing said amplitude reduction of said color-difference signal due to increasing effect of said different threshold level caused by said control signal when said control signal is applied.
Claim 7
Dependent Claim
33 words
A picture quality improving apparatus as claimed in claim 1, wherein said nonlinear processing means consists of means for shunting the load resistor of a color-difference amplifier in response to said control signal.
Claim 8
Dependent Claim
23 words
A picture quality improving apparatus as claimed in claim 1, wherein said nonlinear processing means and said signal detecting means comprise clipping circuits.
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) | 1977-09-09 | 1978-03-11 | 1978-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-09 | 1982-03-11 | 1982-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-09 | 1986-03-11 | 1986-09-10 | $7700.00 | Window Closed / Lapsed |