US6421146B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus and method for shading correction in image scanning system
Assignee: S Printing Solution Co Ltd
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Filing: 1999-05-26
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Granted: 2002-07-16
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Expires: 2019-05-26
Abstract
Abstract A a shading correction apparatus and method for an image scanning system are provided. The shading correction apparatus of an image scanning system includes: an analog/digital converter for converting the analog image signals into digital image data having a preset number of bits; a shading memory for storing a shading factor matrix prepared from a first shading reference pattern at the preset storage time; a time determination corrector for periodically generating correction determination data as shading data achieved from a second shading reference pattern to determine the correction time for optical parts, and informing whether deviation data between correction data at the present time and preset standard data is above a certain allowed value; and a shading corrector to perform shading correction on receipt of the output from the analog/digital converter using the shading factor matrix when the operation of the image scanning system is in a real scan mode.
Inventors
- 👤 Young-Jun Yoo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 15:22
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/04; H04N1/40; H04N1/407; H04N1/4076
Claims Analysis
Total Claims: 42
Claim 1
Independent Claim
189 words
A shading correction apparatus of an image scanning system, comprising: an image sensor to output analog image signals by the photoelectric conversion of an optical density of a document; an analog/digital converter for converting the analog image signals into digital image data having a preset number of bits; a shading memory for storing a shading factor matrix prepared from a first shading reference pattern at a preset storage time for direct shading correction at the location of each corresponding pixel; a timing determination corrector for periodically generating correction determination data as shading data achieved from a second shading reference pattern to determine a correction time for optical parts of the image scanning system when the operation mode of the image scanning system is in a correction determination mode, and to inform whether a deviation data between the correction determination data at a present time and preset standard data is above an allowed value; and a shading corrector for performing shading correction on receipt of the output from the analog/digital converter using the shading factor matrix when the operation of the image scanning system is in a real scan mode.
Claim 2
Dependent Claim
189 words
A shading correction apparatus of an image scanning system, comprising: an image sensor to output analog image signals by the photoelectric conversion of an optical density of a document; an analog/digital converter for converting the analog image signals into digital image data having a preset number of bits; a shading memory for storing a shading factor matrix prepared from a first shading reference pattern at a preset storage time for direct shading correction at the location of each corresponding pixel; a timing determination corrector for periodically generating correction determination data as shading data achieved from a second shading reference pattern to determine a correction time for optical parts of the image scanning system when the operation mode of the image scanning system is in a correction determination mode, and to inform whether a deviation data between the correction determination data at a present time and preset standard data is above an allowed value; and a shading corrector for performing shading correction on receipt of the output from the analog/digital converter using the shading factor matrix when the operation of the image scanning system is in a real scan mode.
Claim 3
Dependent Claim
58 words
The shading correction apparatus of claim 1 , further comprising a shading factor renewer for renewing the shading factor matrix by scanning the first shading reference pattern after performing shading correction for optical parts of the image scanning system on receipt of information from the timing determination corrector that the deviation data is above a preset allowed value.
Claim 4
Dependent Claim
150 words
The shading correction apparatus of claim 2 , wherein the timing determination corrector comprises: a correction memory for storing the preset standard data; a maintenance data generator for receiving correction determination data as shading data achieved from the second shading reference pattern at the correction determination mode from the analog/digital converter and storing the correction determination data into the correction memory; a data comparator for comparing whether the deviation data between the correction determination data at the present time and the preset standard data is above a preset allowed value; and a correction notice informer for informing the correction time to the shading factor renewer if there is a deviation above the preset allowed value as a result of the comparison by the data comparator, and for providing an alarm as to the correction time to a user using at least one of an audio alarm and a visual alarm.
Claim 5
Dependent Claim
43 words
The shading correction apparatus of claim 3 , wherein a maximum pixel light value (M) for the shading factor matrix is achieved by subtracting 1 from the value of 2 to a number (m) of a preset bit power, wherein M=2 m −1.
Claim 6
Dependent Claim
18 words
The shading correction apparatus of claim 4 , wherein the first shading reference pattern comprises a white paper.
Claim 7
Dependent Claim
18 words
The shading correction apparatus of claim 5 , wherein the second shading reference pattern comprises a white roller.
Claim 8
Dependent Claim
34 words
The shading correction apparatus of claim 6 , wherein the preset standard data is shading data for determining the correction time prepared by scanning the second shading reference pattern at the preset storage time.
Claim 9
Dependent Claim
23 words
The shading correction apparatus of claim 7 , wherein the preset storage time is a time of manufacturing of the image scanning system.
Claim 10
Dependent Claim
16 words
The shading correction apparatus of claim 8 , wherein the shading memory comprises a Flash Memory.
Claim 11
Dependent Claim
16 words
The shading correction apparatus of claim 2 , wherein the shading memory comprises a Flash Memory.
Claim 12
Dependent Claim
120 words
The shading correction apparatus of claim 1 , wherein the timing determination corrector comprises: a correction memory for storing the preset standard data; a maintenance data generator for receiving correction determination data as shading data achieved from the second shading reference pattern at the correction determination mode from the analog/digital converter and storing the correction determination data into the correction memory; a data comparator for comparing whether the deviation data between the correction determination data at the present time and the preset standard data is above a preset allowed value; and a correction notice informer for informing the correction time if there is a deviation above the preset allowed value as a result of the comparison by the data comparator.
Claim 13
Dependent Claim
43 words
The shading correction apparatus of claim 11 , wherein a maximum pixel light value (M) for the shading factor matrix is achieved by subtracting 1 from the value of 2 to a number (m) of a preset bit power, wherein M=2 m −1.
Claim 14
Dependent Claim
34 words
The shading correction apparatus of claim 12 , wherein the preset standard data is shading data for determining the correction time prepared by scanning the second shading reference pattern at the preset storage time.
Claim 15
Dependent Claim
23 words
The shading correction apparatus of claim 13 , wherein the preset storage time is a time of manufacturing of the image scanning system.
Claim 16
Dependent Claim
16 words
The shading correction apparatus of claim 14 , wherein the shading memory comprises a Flash Memory.
Claim 17
Dependent Claim
43 words
The shading correction apparatus of claim 1 , wherein a maximum pixel light value (M) for the shading factor matrix is achieved by subtracting 1 from the value of 2 to a number (m) of a preset bit power, wherein M=2 m −1.
Claim 18
Dependent Claim
58 words
The shading correction apparatus of claim 16 , further comprising a shading factor renewer for renewing the shading factor matrix by scanning the first shading reference pattern after performing shading correction for optical parts of the image scanning system on receipt of information from the timing determination corrector that the deviation data is above a preset allowed value.
Claim 19
Dependent Claim
18 words
The shading correction apparatus of claim 1 , wherein the first shading reference pattern comprises a white paper.
Claim 20
Dependent Claim
18 words
The shading correction apparatus of claim 1 , wherein the second shading reference pattern comprises a white roller.
Claim 21
Dependent Claim
34 words
The shading correction apparatus of claim 1 , wherein the preset standard data is shading data for determining the correction time prepared by scanning the second shading reference pattern at the preset storage time.
Claim 22
Dependent Claim
23 words
The shading correction apparatus of claim 1 , wherein the preset storage time is a time of manufacturing of the image scanning system.
Claim 23
Independent Claim
203 words
A method for shading correction for an image scanning system to read image data of a document by photoelectric conversion, comprising the steps of: producing and storing a shading factor matrix comprising shading factors corresponding to each pixel location from a scanned image of a first shading reference pattern at a preset storage time; storing shading data achieved by scanning a second shading reference pattern as a standard data to determine a correction time; determining whether the operation mode of the image scanning system is a real scan mode for real-scanning or a correction determination mode for determining the correction time; performing shading correction by multiplying (a) digital image data output after analog to digital converting a scanned document and (b) the shading factor matrix for the each pixel location, if the operation mode of the image scanning system is the real scan mode; and determining the correction time by periodically preparing correction determination data as shading data achieved from the second shading reference pattern, if the operation mode of the image scanning system is the correction determination mode, and determining whether deviation data between the correction determination data at a present time and the standard data is above a preset allowed value.
Claim 24
Independent Claim
203 words
A method for shading correction for an image scanning system to read image data of a document by photoelectric conversion, comprising the steps of: producing and storing a shading factor matrix comprising shading factors corresponding to each pixel location from a scanned image of a first shading reference pattern at a preset storage time; storing shading data achieved by scanning a second shading reference pattern as a standard data to determine a correction time; determining whether the operation mode of the image scanning system is a real scan mode for real-scanning or a correction determination mode for determining the correction time; performing shading correction by multiplying (a) digital image data output after analog to digital converting a scanned document and (b) the shading factor matrix for the each pixel location, if the operation mode of the image scanning system is the real scan mode; and determining the correction time by periodically preparing correction determination data as shading data achieved from the second shading reference pattern, if the operation mode of the image scanning system is the correction determination mode, and determining whether deviation data between the correction determination data at a present time and the standard data is above a preset allowed value.
Claim 25
Dependent Claim
35 words
The method of claim 22 , further comprising the step of renewing the shading factor matrix by scanning the first shading reference pattern after performing shading correction on receipt of information of the correction time.
Claim 26
Dependent Claim
116 words
The method of claim 23 , wherein the step of producing and storing the shading factor matrix comprises the steps of: determining a plurality of first scanning data by repeating at least one time scanning the first shading reference pattern; providing shading data by averaging the plurality of the first scanning data by a scanning time; producing the shading factor matrix by dividing the shading data by a preset maximum pixel light value and then storing the shading factor matrix; determining a plurality of second scanning data by repeating at least one time scanning the second shading reference pattern; and storing data determined by averaging the plurality of the second scanning data as the standard data.
Claim 27
Dependent Claim
79 words
The method of claim 24 , wherein the step of determining the correction time comprises the steps of: storing the correction determination data achieved from the second shading reference pattern at the correction determination mode; comparing whether there is a deviation between the correction determination data at the present time and the standard data above the preset allowed value; and generating an order to renew the shading factor matrix if there is a deviation above the preset allowed value.
Claim 28
Dependent Claim
41 words
The method of claim 25 , wherein a maximum pixel light value (M) for the shading factor matrix is achieved by subtracting 1 from the value of 2 to a number (m) of a preset bit power, wherein M=2 m −1.
Claim 29
Dependent Claim
26 words
The method of claim 26 , wherein the standard data is shading data prepared by scanning the second shading reference pattern at the preset storage time.
Claim 30
Dependent Claim
20 words
The method of claim 27 , wherein the preset storage time is a time of manufacturing the image scanning system.
Claim 31
Dependent Claim
16 words
The method of claim 27 , wherein the first shading reference pattern comprises a white paper.
Claim 32
Dependent Claim
16 words
The method of claim 27 , wherein the second shading reference pattern comprises a white roller.
Claim 33
Dependent Claim
116 words
The method of claim 22 , wherein the step of producing and storing the shading factor matrix comprises the steps of: determine a plurality of first scanning data by repeating at least one time scanning the first shading reference pattern; providing shading data by averaging the plurality of the first scanning data by a scanning time; producing the shading factor matrix by dividing the shading data by a preset maximum pixel light value and then storing the shading factor matrix; determining a plurality of second scanning data by repeating at least one time scanning the second shading reference pattern; and storing data determined by averaging the plurality of the second scanning data as the standard data.
Claim 34
Dependent Claim
79 words
The method of claim 31 , wherein the step of determining the correction time comprises the steps of: storing the correction determination data achieved from the second shading reference pattern at the correction determination mode; comparing whether there is a deviation between the correction determination data at the present time and the standard data above the preset allowed value; and generating an order to renew the shading factor matrix if there is a deviation above the preset allowed value.
Claim 35
Dependent Claim
41 words
The method of claim 32 , wherein a maximum pixel light value (M) for the shading factor matrix is achieved by subtracting 1 from the value of 2 to a number (m) of a preset bit power, wherein M=2 m −1.
Claim 36
Dependent Claim
116 words
The method of claim 22 , wherein the step of producing and storing the shading factor matrix comprises the steps of: determining a plurality of first scanning data by repeating at least one time scanning the first shading reference pattern; providing shading data by averaging the plurality of the first scanning data by a scanning time; producing the shading factor matrix by dividing the shading data by a preset maximum pixel light value and then storing the shading factor matrix; determining a plurality of second scanning data by repeating at least one time scanning the second shading reference pattern; and storing data determined by averaging the plurality of the second scanning data as the standard data.
Claim 37
Dependent Claim
79 words
The method of claim 22 , wherein the step of determining the correction time comprises the steps of: storing the correction determination data achieved from the second shading reference pattern at the correction determination mode; comparing whether there is a deviation between the correction determination data at the present time and the standard data above the preset allowed value; and generating an order to renew the shading factor matrix if there is a deviation above the preset allowed value.
Claim 38
Dependent Claim
41 words
The method of claim 22 , wherein a maximum pixel light value (M) for the shading factor matrix is achieved by subtracting 1 from the value of 2 to a number (m) of a preset bit power, wherein M=2 m −1.
Claim 39
Dependent Claim
16 words
The method of claim 22 , wherein the first shading reference pattern comprises a white paper.
Claim 40
Dependent Claim
16 words
The method of claim 22 , wherein the second shading reference pattern comprises a white roller.
Claim 41
Dependent Claim
26 words
The method of claim 22 , wherein the standard data is shading data prepared by scanning the second shading reference pattern at the preset storage time.
Claim 42
Dependent Claim
19 words
The method of claim 22 , wherein the preset storage time is time of manufacturing the image scanning system.
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| 7.5 Years (Year 8) | 2009-07-15 | 2010-01-14 | 2010-07-16 | $3760.00 | Window Closed / Lapsed |
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