Television – Image signal processing circuitry specific to television – Matrixing or mixing
Patent
1997-05-08
2000-10-31
Powell, Mark R.
Television
Image signal processing circuitry specific to television
Matrixing or mixing
348531, 348642, 348661, 348697, H04N 972
Patent
active
061410640
ABSTRACT:
A luminance signal generation circuit with single clamp generates a separate luminance signal Y by combining RGB input signals in a weighted manner within a Y-Matrix circuit. During a burst period the single clamping circuit is enabled. When enabled, the single clamping circuit compares the separate luminance signal Y to a constant reference voltage signal. A difference signal, representing the difference between the separate luminance signal Y and the constant reference voltage signal, is used to adjust a blanking level of the RGB input signals until the blanking level of the separate luminance signal Y is equal to the constant reference voltage signal. During the non-burst periods the single clamping circuit is disabled and the Y-Matrix circuit combines the RGB input signals into the separate luminance signal Y. Preferably, the single clamping circuit sets the blank level of the separate luminance signal Y to a level equal to two volts. NPN transistor follower circuits are utilized within the clamping circuit and with input receiving circuits to provide the RGB input signals to the Y-Matrix circuit.
REFERENCES:
patent: 4295161 (1981-10-01), Hettiger
patent: 4473839 (1984-09-01), Noda
patent: 4667242 (1987-05-01), Hagino
patent: 4717953 (1988-01-01), Chang et al.
patent: 4866511 (1989-09-01), Belmares-Sarabia et al.
patent: 4930004 (1990-05-01), Yamamoto et al.
patent: 4965669 (1990-10-01), Canfield et al.
patent: 5126831 (1992-06-01), Nakagawara
patent: 5182497 (1993-01-01), Yamate et al.
patent: 5272522 (1993-12-01), Lagoni
patent: 5291276 (1994-03-01), Matsumoto
patent: 5339114 (1994-08-01), Lagoni et al.
patent: 5371552 (1994-12-01), Brummette
patent: 5448308 (1995-09-01), Walby
patent: 5638137 (1997-06-01), Thomas
patent: 5864371 (1999-01-01), Nayebi
Nayebi Mehrdad
Ngo Duc
Powell Mark R.
Sajous Wesner
Sony Corporation
Sony Electronics Inc.
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