US6707491B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of correcting white balance in video camera
Assignee: Hanwha Vision Co Ltd
•
Filing: 1999-08-23
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Granted: 2004-03-16
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Expires: 2019-08-23
Abstract
Abstract A method of correcting white balance in a video camera is provided, which controls the red gain and blue gain of a captured image signal to allow the average of color difference signals of a picture, the method including the steps of (a) dividing the captured image of one picture into a predetermined number of unit cells, and accumulating the color difference signals by cells divided, (b) extracting an effective cell according as the accumulated data of each of the unit cells is data required for white balance correction or not, (c) judging whether data of the effective cell extracted in step (b) is monochrome data or mixed color data, (d) performing white balance correction without using the effective cell when the data of the effective cell is judged to be mixed color data in step (c), and (e) carrying out white balance correction using the effective cell when the data of the effective cell is judged to be monochrome data in step (c).
Inventors
- 👤 Ki Young Choi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:10
CPC Classifications
H; H04; H04N; H04N23/00; H04N23/80; H04N23/84; H04N23/88
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
162 words
A method of correcting white balance in a video camera, which controls the red gain and blue gain of a captured image signal to allow the average of color difference signals of a picture, the method comprising the steps of: (a) dividing the captured image of one picture into a predetermined number of unit cells, and accumulating the color difference signals by cells divided; (b) extracting an effective cell according as the accumulated data of each of the unit cells is data required for white balance correction or not; (c) judging whether data of the effective cell extracted in step (b) is monochrome data or mixed color data; (d) performing white balance correction without using the effective cell when the data of the effective cell is judged to be mixed color data in step (c); and (e) carrying out white balance correction using the effective cell when the data of the effective cell is judged to be monochrome data in step (c).
Claim 2
Independent Claim
162 words
A method of correcting white balance in a video camera, which controls the red gain and blue gain of a captured image signal to allow the average of color difference signals of a picture, the method comprising the steps of: (a) dividing the captured image of one picture into a predetermined number of unit cells, and accumulating the color difference signals by cells divided; (b) extracting an effective cell according as the accumulated data of each of the unit cells is data required for white balance correction or not; (c) judging whether data of the effective cell extracted in step (b) is monochrome data or mixed color data; (d) performing white balance correction without using the effective cell when the data of the effective cell is judged to be mixed color data in step (c); and (e) carrying out white balance correction using the effective cell when the data of the effective cell is judged to be monochrome data in step (c).
Claim 3
Dependent Claim
50 words
The method as claimed in claim 1 , wherein the judgment whether the data accumulated in each of the unit cells is data required for white balance correction or not in step (b) is carried out according as the accumulated data exists in a predetermined region including blackbody radiation curve.
Claim 4
Dependent Claim
40 words
The method as claimed in claim 2 , wherein the judgement whether data of the effective cell is monochrome data or mixed color data in step (c) is carried out according to the amount of AF data corresponding cell has.
Claim 5
Dependent Claim
63 words
The method as claimed in claim 3 , wherein, for a cell whose data is judged to be monochrome data on the basis of the amount of AF data, the correlation between the cell and its neighboring cells is checked, and it is finally judged whether the data of the cell is monochrome data or mixed color data according to the checked result.
Claim 6
Dependent Claim
64 words
The method as claimed in claim 4 , wherein the correlation between corresponding cell and its neighboring cells is calculated on the basis of the distance difference between vector sum of color difference signal data accumulated in the corresponding cell and vector sum of color difference signal data of neighboring cells located in the upper, lower, left and right sides of the corresponding cell.
Claim 7
Dependent Claim
41 words
The method as claimed in claim 2 , wherein the judgement whether data of the effective cell is monochrome data or mixed color data in step (c) is carried out according to the correlation between corresponding cell and its neighboring cells.
Claim 8
Dependent Claim
64 words
The method as claimed in claim 6 , wherein the correlation between corresponding cell and its neighboring cells is calculated on the basis of the distance difference between vector sum of color difference signal data accumulated in the corresponding cell and vector sum of color difference signal data of neighboring cells located in the upper, lower, left and right sides of the corresponding cell.
Claim 9
Dependent Claim
81 words
The method as claimed in claim 2 , wherein the judgement whether data of the effective cell is monochrome data or mixed color data in step (c) is carried out by combining the weight as effective data on the basis of the amount of AF data of corresponding cell with the weight as effective data that the correlation between corresponding cell and its neighboring cells has, to calculate the final weight, and then comparing the final_weight with a predetermined reference value.
Claim 10
Dependent Claim
17 words
The method as claimed in claim 1 , wherein the number of the unit cells equals 64.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2007-03-16 | 2007-09-15 | 2008-03-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2011-03-16 | 2011-09-15 | 2012-03-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2015-03-16 | 2015-09-15 | 2016-03-16 | $7700.00 | Window Closed / Lapsed |