US5745172A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Noise elimination circuit in negative image pickup apparatus
Assignee: Fujifilm Corp
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Filing: 1995-04-24
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Granted: 1998-04-28
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Expires: 2015-04-24
Abstract
Abstract A luminance signal obtained by negative-positive inverting and gamma-correcting a signal indicating an image on a negative film and a contour correction signal Y ap generated from the luminance signal Y are input, and a signal Y ap1 and a signal Y ap2 are obtained by an adder, a subtractor and an adder in accordance with following equations: Y.sub.ap1 =Y.sub.ap -kY, Y.sub.ap2 =Y.sub.ap +kY, where K is a damping coefficient. Next, a slice circuit picks out signals having a higher level than the maximum level of the noise element, from the signal Y ap1 generated as mentioned above and another slice circuit picks out signals having a lower level than the minimum level of the noise element, from the signal Y ap2 . An adder adds up these picked-out signals to be used as the noise free contour correction signal.
Inventors
- 👤 Mamoru Miyashita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 02:30
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/14; H04N5/21; H04N1/00; H04N1/46; H04N1/56; H04N1/60; H04N1/6027; H04N23/00; H04N23/80; H04N23/82; H04N23/83; H04N5/20; H04N5/205; H04N5/208; H04N9/00; H04N9/64; H04N9/646
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
165 words
A noise elimination circuit in a negative image pickup apparatus which receives a luminance signal obtained by negative-positive inverting and gamma-correcting a signal indicating an image on a negative film and a contour correction signal generated from said luminance signal and which eliminates a noise included in said contour correction signal, comprising: means for generating a signal Y ap1 and a signal Y ap2 in accordance with a following equation when said luminance signal is Y and said contour correction signal is Y ap : Y.sub.ap1 =Y.sub.ap -kY Y.sub.ap2 =Y.sub.ap +kY, where k is an attenuating coefficient; a first slice circuit which picks out signals having a higher level than a maximum level of a noise element in said signal Y ap1 ; a second slice circuit which picks out signals having a lower level than a minimum level of a noise element in said signal Y ap2 ; and, an adder which adds up signals picked out by said first and second slice circuits.
Claim 2
Dependent Claim
165 words
A noise elimination circuit in a negative image pickup apparatus which receives a luminance signal obtained by negative-positive inverting and gamma-correcting a signal indicating an image on a negative film and a contour correction signal generated from said luminance signal and which eliminates a noise included in said contour correction signal, comprising: means for generating a signal Y ap1 and a signal Y ap2 in accordance with a following equation when said luminance signal is Y and said contour correction signal is Y ap : Y.sub.ap1 =Y.sub.ap -kY Y.sub.ap2 =Y.sub.ap +kY, where k is an attenuating coefficient; a first slice circuit which picks out signals having a higher level than a maximum level of a noise element in said signal Y ap1 ; a second slice circuit which picks out signals having a lower level than a minimum level of a noise element in said signal Y ap2 ; and, an adder which adds up signals picked out by said first and second slice circuits.
Claim 3
Dependent Claim
33 words
The noise elimination circuit in the negative scanner as set forth in claim 1, wherein a gamma value of a curve in a gamma-correction for obtaining said luminance signal is more than 1.
Claim 4
Dependent Claim
69 words
The noise elimination circuit in the negative scanner as set forth in claim 2, wherein an outline of a plot of a signal ky which is obtained by multiplying said attenuating coefficient k by said luminance signal y versus luminance has the same inclination as that of an outline of a plot of a maximum value of a noise included in said contour correction signal Y ap versus luminance.
Claim 5
Dependent Claim
27 words
The noise elimination circuit in the negative scanner as set forth in claim 1, wherein a signal output from said adder serves as the contour correction signal.
Claim 6
Independent Claim
147 words
A method for eliminating noise in a negative image pickup apparatus which receives a luminance signal obtained by negative-positive inverting and gamma-correcting a signal indicating an image on a negative film and a contour correction signal generated from said luminance signal, the method eliminating noise in said contour correction signal, comprising the steps of: generating a signal Y ap1 and a signal Y ap2 in accordance with a following equation when said luminance signal is Y and said contour correction signal Y ap : Y.sub.ap1 =Y.sub.ap -kY Y.sub.ap2 =Y.sub.ap +kY, where k is an attenuating coefficient; picking out first signals having a higher level than a maximum level of a noise element in said signal Y ap ; picking out second signals having a lower level than a minimum level of a noise element in said signal Y ap2 ; and, adding said first and second signals.
Claim 7
Independent Claim
147 words
A method for eliminating noise in a negative image pickup apparatus which receives a luminance signal obtained by negative-positive inverting and gamma-correcting a signal indicating an image on a negative film and a contour correction signal generated from said luminance signal, the method eliminating noise in said contour correction signal, comprising the steps of: generating a signal Y ap1 and a signal Y ap2 in accordance with a following equation when said luminance signal is Y and said contour correction signal Y ap : Y.sub.ap1 =Y.sub.ap -kY Y.sub.ap2 =Y.sub.ap +kY, where k is an attenuating coefficient; picking out first signals having a higher level than a maximum level of a noise element in said signal Y ap ; picking out second signals having a lower level than a minimum level of a noise element in said signal Y ap2 ; and, adding said first and second signals.
Claim 8
Dependent Claim
27 words
The method as set forth in claim 5, wherein a gamma value of a curve in a gamma-correction for obtaining said luminance signal is more than 1.
Claim 9
Dependent Claim
58 words
The method as set forth in claim 5, further including selecting said attenuating coefficient k so that an outline of a plot of a product of k and said luminance signal y versus luminance has the same inclination as that of an outline of a plot of maximum noise of said contour correction signal Y ap versus luminance.
Claim 10
Dependent Claim
21 words
The method as set forth in claim 5, further including delivering a signal from said adding as said contour correction signal.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2001-04-27 | 2001-10-27 | 2002-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-04-27 | 2005-10-27 | 2006-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-04-27 | 2009-10-27 | 2010-04-28 | $7700.00 | Window Closed / Lapsed |