Patent US5760831A successfully refreshed from Google Patents.
US5760831A
Expired / Lapsed
US
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Image processing apparatus with white balance control
Assignee: Canon Inc
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Filing: 1995-09-08
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Granted: 1998-06-02
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Expires: 2015-09-08
Abstract
Abstract An image processing apparatus comprises a coefficient generation circuit for generating a coefficient such as to decrease as a level of a luminance signal which is obtained by processing an input image signal increases while exceeding a predetermined limit value and to decrease as the luminance signal level decreases to a value lower than a predetermined lower limit value, a multiplier for multiplying a color difference signal which is obtained by processing the input image signal and the coefficient generated from the coefficient generation circuit, an integrating circuit for integrating the multiplication output from the multiplier into a plurality of predetermined regions on a screen, and a white balance control circuit to control the white balance of the screen by using the integration output of the integrating circuit.
Inventors
- 👤 Yasuyuki Tanaka
- 👤 Osamu Ueda
- 👤 Norihiro Kawahara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 13:58
CPC Classifications
H; H04; H04N; H04N23/00; H04N23/80; H04N23/84; H04N23/88
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
123 words
A white balance control apparatus comprising: coefficient generating means for generating a coefficient so as to decrease as the level of a luminance signal, which is obtained by processing an input image signal, increases while exceeding a predetermined upper limit value and so as to decrease as such a level decreases than a predetermined lower limit value; multiplying means for multiplying color difference signals obtained by processing the input image signal and the coefficient generated by said coefficient generating means; integrating means for integrating multiplication outputs of said multiplying means every plurality of regions which have been predetermined on a screen; and a white balance control circuit to control a white balance on the screen by using integration outputs of the integrating means.
Claim 2
Dependent Claim
123 words
A white balance control apparatus comprising: coefficient generating means for generating a coefficient so as to decrease as the level of a luminance signal, which is obtained by processing an input image signal, increases while exceeding a predetermined upper limit value and so as to decrease as such a level decreases than a predetermined lower limit value; multiplying means for multiplying color difference signals obtained by processing the input image signal and the coefficient generated by said coefficient generating means; integrating means for integrating multiplication outputs of said multiplying means every plurality of regions which have been predetermined on a screen; and a white balance control circuit to control a white balance on the screen by using integration outputs of the integrating means.
Claim 3
Dependent Claim
14 words
An apparatus according to claim 1, wherein said plurality of regions are irregularly arranged.
Claim 4
Dependent Claim
91 words
An image pickup apparatus comprising: coefficient generating means for generating a coefficient which decreases when the level of a luminance signal exceeds a predetermined limit; multiplying means for multiplying color difference signals obtained by processing the input image signal and the coefficient generated by said coefficient generating means; integrating means for integrating multiplication outputs of said multiplying means every plurality of regions which have been predetermined on a screen; and a white balance control circuit to control a white balance on the screen by using integration outputs of the integrating means.
Claim 5
Dependent Claim
91 words
An image pickup apparatus comprising: coefficient generating means for generating a coefficient which decreases when the level of a luminance signal exceeds a predetermined limit; multiplying means for multiplying color difference signals obtained by processing the input image signal and the coefficient generated by said coefficient generating means; integrating means for integrating multiplication outputs of said multiplying means every plurality of regions which have been predetermined on a screen; and a white balance control circuit to control a white balance on the screen by using integration outputs of the integrating means.
Claim 6
Dependent Claim
14 words
An apparatus according to claim 3, wherein said plurality of regions are irregularly arranged.
References Cited (Backward Citations)
JPS6229296A
Cited
JPH0250592A
Cited
JPH0250489A
Cited
US5270802A
Cited
US5040054A
Cited
JPH03259692A
Cited
JPH03289793A
Cited
US5223921A
Cited
US5267026A
Cited
US5361093A
Cited
US5274440A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-06-01 | 2001-12-01 | 2002-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-06-01 | 2005-12-01 | 2006-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-06-01 | 2009-12-01 | 2010-06-02 | $7700.00 | Window Closed / Lapsed |