US5485202A
Expired / Lapsed
US
⏱️ 0.0 years remaining
White balance adjusting apparatus
Assignee: Canon Inc
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Filing: 1994-03-01
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Granted: 1996-01-16
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Expires: 2014-03-01
Abstract
Abstract In a white balance adjusting apparatus, information about picture portions whose color components cannot be detected under normal conditions, e.g., picture portions whose brightness level is excessively high, or excessively low, are suppressed from white balance controlling data, so that data required for the white balance control can be correctly obtained without using small windows which a frame of picture is subdivided into. For this purpose, signals of predetermined window portions within one frame of picture are integrated by integration circuits, while weighting the signals by multiplication factor generating means based on brightness level, and then a white balance control is carried out by using an integrated value.
Inventors
- 👤 Osamu Ueda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 11:22
CPC Classifications
H; H04; H04N; H04N23/00; H04N23/80; H04N23/84; H04N23/88
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
164 words
A white balance adjusting apparatus comprising: an image pickup device for picking up an object image; image signal processing means for processing an image signal produced from the image pickup device and for deriving a brightness signal and color information signals; multiplication factor generating means for generating a variable multiplication factor in response to the brightness signal in such a manner that a high multiplication factor is set when the value of the brightness signal is within a predetermined range, whereas a multiplication factor lower than the above is set when the value of the brightness signal is out of said predetermined range; computing means for computing between multiplication factor derived from said multiplication factor generating means and said color information signals; integrating means for integrating output data from said computing means; and white balance controlling means for performing a white balance control to correct said image signal within said image signal processing means based upon the integrated data derived from said integrating means.
Claim 2
Dependent Claim
164 words
A white balance adjusting apparatus comprising: an image pickup device for picking up an object image; image signal processing means for processing an image signal produced from the image pickup device and for deriving a brightness signal and color information signals; multiplication factor generating means for generating a variable multiplication factor in response to the brightness signal in such a manner that a high multiplication factor is set when the value of the brightness signal is within a predetermined range, whereas a multiplication factor lower than the above is set when the value of the brightness signal is out of said predetermined range; computing means for computing between multiplication factor derived from said multiplication factor generating means and said color information signals; integrating means for integrating output data from said computing means; and white balance controlling means for performing a white balance control to correct said image signal within said image signal processing means based upon the integrated data derived from said integrating means.
Claim 3
Dependent Claim
76 words
A white balance adjusting apparatus as claimed in claim 1, wherein said multiplication factor generating means is such that a high value of the multiplication factor is set to a predetermined value when the value of the brightness signal is within said predetermined range, and a value of the multiplication factor is lower than the above and gradually decreased down to 0 (zero) when the value of the brightness signal is out of said predetermined range.
Claim 4
Dependent Claim
29 words
A white balance adjusting apparatus as claimed in claim 1 or 2, wherein said multiplication factor generating means includes a multiplication factor generator and a multiplication factor control circuit.
Claim 5
Dependent Claim
32 words
A white balance adjusting apparatus as claimed in claim 1, wherein said multiplication factor generating means includes a multiplication factor setting means capable of selectively setting said value of the multiplication factor.
Claim 6
Dependent Claim
20 words
A white balance adjusting apparatus as claimed in claim 4, wherein said multiplication factor generating means is a selector switch.
Claim 7
Dependent Claim
46 words
A white balance adjusting apparatus as claimed in claim 1, wherein said multiplication factor generating means includes a multiplication factor changing means for computing a mean value of said brightness signal for automatically changing the value of said multiplication factor based upon the obtained mean value.
Claim 8
Dependent Claim
16 words
A white balance adjusting apparatus as claimed in claim 1, wherein said computing means are multipliers.
Claim 9
Dependent Claim
33 words
A white balance adjusting apparatus as claimed in claim 1, wherein said integrating means includes an adder and an integration register to which an output signal of a window generating circuit is applied.
Claim 10
Dependent Claim
199 words
A white balance adjusting apparatus comprising: an image pickup device for picking up an object image; image signal processing means for processing an image signal produced from the image pickup device and for deriving a brightness signal and color information signals; multiplication factor generating means for generating a variable multiplication factor in response to the brightness signal in such a manner that a high multiplication factor is set when the value of the brightness signal is within a predetermined range, whereas a multiplication factor lower than the above is set when the value of the brightness signal is out of said predetermined range; said multiplication factor generating means including a multiplication factor changing means for computing a mean value of said brightness signal for automatically changing the value of said multiplication factor based upon the obtained mean value; computing means for computing between multiplication factor derived from said multiplication factor generating means and said color information signals; integrating means for integrating output data from said computing means; and white balance controlling means for performing a white balance control to correct said image signal within said image signal processing means based upon the integrated data derived from said integrating means.
Claim 11
Dependent Claim
199 words
A white balance adjusting apparatus comprising: an image pickup device for picking up an object image; image signal processing means for processing an image signal produced from the image pickup device and for deriving a brightness signal and color information signals; multiplication factor generating means for generating a variable multiplication factor in response to the brightness signal in such a manner that a high multiplication factor is set when the value of the brightness signal is within a predetermined range, whereas a multiplication factor lower than the above is set when the value of the brightness signal is out of said predetermined range; said multiplication factor generating means including a multiplication factor changing means for computing a mean value of said brightness signal for automatically changing the value of said multiplication factor based upon the obtained mean value; computing means for computing between multiplication factor derived from said multiplication factor generating means and said color information signals; integrating means for integrating output data from said computing means; and white balance controlling means for performing a white balance control to correct said image signal within said image signal processing means based upon the integrated data derived from said integrating means.
Claim 12
Dependent Claim
76 words
A white balance adjusting apparatus as claimed in claim 9, wherein said multiplication factor generating means is such that a high value of the multiplication factor is set to a predetermined value when the value of the brightness signal is within said predetermined range, and a value of the multiplication factor is lower than the above and gradually decreased down to 0 (zero) when the value of the brightness signal is out of said predetermined range.
Claim 13
Dependent Claim
29 words
A white balance adjusting apparatus as claimed in claim 9 or 10, wherein said multiplication factor generating means includes a multiplication factor generator and a multiplication factor control circuit.
Claim 14
Dependent Claim
32 words
A white balance adjusting apparatus as claimed in claim 9, wherein said multiplication factor generating means includes a multiplication factor setting means capable of selectively setting said value of the multiplication factor.
Claim 15
Dependent Claim
20 words
A white balance adjusting apparatus as claimed in claim 12, wherein said multiplication factor generating means is a selector switch.
Claim 16
Dependent Claim
36 words
A white balance adjusting apparatus as claimed in claim 9, wherein said multiplication factor generating means includes a multiplication factor changing means for automatically changing the value of said multiplication factor based upon said brightness signal.
Claim 17
Dependent Claim
16 words
A white balance adjusting apparatus as claimed in claim 9, wherein said computing means are multipliers.
Claim 18
Dependent Claim
33 words
A white balance adjusting apparatus as claimed in claim 9, wherein said integrating means includes an added and an integration register to which an output signal of a window generating circuit is applied.
References Cited (Backward Citations)
US5099316A
Cited
US5223921A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-01-15 | 1999-07-17 | 2000-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-01-15 | 2003-07-17 | 2004-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-01-15 | 2007-07-17 | 2008-01-16 | $7700.00 | Window Closed / Lapsed |