US5140424A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image signal processing apparatus with noise reduction
Assignee: Canon Inc
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Filing: 1991-04-12
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Granted: 1992-08-18
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Expires: 2011-04-12
Abstract
Abstract An image signal processing apparatus inputs a video signal, delays it by one field using a field memory, multiplies the delayed signal by a value K (K less than 1), adds the output from the multiplication to the input signal and supplies the sum to the field memory. The level of the signal read out from the field memory is compared with a predetermined value, and based on the result of that comparison, the video signal being input is substantially inhibited from being supplied to the adding means. The signal obtained by multiplying the immediately-preceding field signal by k, and the present-field signal, are cyclically added, so that the amplitude can be gradually increased. The comparison inhibits addition of a new field signal when the level of that stored in the field memory has reached a predetermined level.
Inventors
- 👤 Katsuji Yoshimura
- 👤 Yoshitake Nagashima
- 👤 Teruo Hieda
- 👤 Tadayoshi Nakayama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 16:54
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/14; H04N5/21
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
79 words
An image signal processing apparatus comprising: means for amplifying an input image signal with a predetermined gain, wherein said input image signal is an image signal supplied from an image pickups element; means for reducing noise of the image signal amplified by said amplifying means; means for detecting a level of the input image signal; and means for controlling an operation of said noise reducing means and said amplifying means in accordance with an output of said detecting means.
Claim 2
Dependent Claim
79 words
An image signal processing apparatus comprising: means for amplifying an input image signal with a predetermined gain, wherein said input image signal is an image signal supplied from an image pickups element; means for reducing noise of the image signal amplified by said amplifying means; means for detecting a level of the input image signal; and means for controlling an operation of said noise reducing means and said amplifying means in accordance with an output of said detecting means.
Claim 3
Dependent Claim
48 words
An apparatus according to claim 1, wherein said noise reducing means includes: a memory for storing the image signal; and means for controlling write access of the image signal in said memory, said write access controlling means reducing the noise by adding image signals written in said memory.
Claim 4
Dependent Claim
34 words
An apparatus according to claim 1, wherein said operation controlling means controls said noise reducing means not to perform noise reduction when a gain of said amplifying means is smaller than a predetermined level.
Claim 5
Dependent Claim
17 words
An apparatus according to claim 1, further comprising means for changing the gain of said amplifying means.
Claim 6
Dependent Claim
108 words
An image signal processing apparatus, comprising: means for amplifying an input iamge signal with a predetermined gain; means for reducing noise of the input iamge signal amplified by said amplifying means; means for detecting a level of the input image signal; means for controlling an operation of said noise reducing means and said amplifying means in accordance with an output of said detecting means; and means for changing the gain of said amplifying means, said changing means including a manual switch for changing the gain of said amplifying means and automatic gain control means for automatically controlling gain in accordance with a level of the input image signal.
Claim 7
Dependent Claim
108 words
An image signal processing apparatus, comprising: means for amplifying an input iamge signal with a predetermined gain; means for reducing noise of the input iamge signal amplified by said amplifying means; means for detecting a level of the input image signal; means for controlling an operation of said noise reducing means and said amplifying means in accordance with an output of said detecting means; and means for changing the gain of said amplifying means, said changing means including a manual switch for changing the gain of said amplifying means and automatic gain control means for automatically controlling gain in accordance with a level of the input image signal.
Claim 8
Dependent Claim
21 words
An apparatus according to claim 5, wherein said input image signal is an image signal supplied from an image pickup element.
Claim 9
Dependent Claim
50 words
An apparatus according to claim 5, wherein said noise reducing means includes: a memory for storing the input image signal; and means for controlling write access of the input image signal in said memory, said write access controlling means reducing the noise by adding image signals written in said memory.
Claim 10
Dependent Claim
35 words
An apparatus according to claim 5, wherein said operation controlling means controls said noise reducing means not to perform noise reduction when the gain of said amplifying means is smaller than a second predetermined gain.
Claim 11
Dependent Claim
93 words
An image signal processing apparatus comprising: means for amplifying an input image signal with a predetermined gain; means for reducing noise of the input image signal amplified by said amplifying means, said noise reducing means further comprising memory means for storing the input image signal; means for detecting a level of the input image signal; and means for controlling an operation of said noise reducing means and said amplifying means in accordance with an output of said detecting means, wherein said memory comprises a memory for storing at least a one-frame image signal.
Claim 12
Dependent Claim
93 words
An image signal processing apparatus comprising: means for amplifying an input image signal with a predetermined gain; means for reducing noise of the input image signal amplified by said amplifying means, said noise reducing means further comprising memory means for storing the input image signal; means for detecting a level of the input image signal; and means for controlling an operation of said noise reducing means and said amplifying means in accordance with an output of said detecting means, wherein said memory comprises a memory for storing at least a one-frame image signal.
Claim 13
Dependent Claim
13 words
An apparatus according to claim 9, wherein said memory comprises a field memory.
Claim 14
Dependent Claim
21 words
An apparatus according to claim 9, wherein said input image signal is an image signal supplied from an image pickup element.
Claim 15
Dependent Claim
34 words
An apapratus according to claim 9, wherein said operation controlling means controls said noise reducing means not to perform noise reduction when the gain of said amplifying means is smaller than a predetermined gain.
Claim 16
Dependent Claim
17 words
An apparatus according to claim 9, further comprising means for changing the gain of said amplifying means.
Claim 17
Dependent Claim
97 words
An image signal processing apparatus comprising: means for amplifying an input image signal with a predetermined gain; a field cyclic processing circuit having a field memory, for processing the input image signal amplified by said amplifying means, by combining an image signal delayed by said field memory and the input image signal amplified by said amplifying means and not delayed by said field memory; means for detecting a level of the input image signal; and means for controlling an operation of said processing circuit and said amplifying means in accordance with an output of said detecting means.
Claim 18
Dependent Claim
97 words
An image signal processing apparatus comprising: means for amplifying an input image signal with a predetermined gain; a field cyclic processing circuit having a field memory, for processing the input image signal amplified by said amplifying means, by combining an image signal delayed by said field memory and the input image signal amplified by said amplifying means and not delayed by said field memory; means for detecting a level of the input image signal; and means for controlling an operation of said processing circuit and said amplifying means in accordance with an output of said detecting means.
Claim 19
Dependent Claim
23 words
An apparatus according to claim 14, wherein said control means interrupts the operation of said processing circuit in accordance with the predetermined gain.
Claim 20
Dependent Claim
74 words
An image processing apparatus comprising: (a) means for amplifying an input image signal with a predetermined gain; (b) field cyclic noise reduction means for reducing a noise component of said amplifying means, said field cyclic noise reduction means reducing noise by combining two successive field image signals, in a ratio corresponding to a first parameter; and (c) means for controlling the first parameter in accordance with a second parameter, corresponding to said amplifying means.
Claim 21
Dependent Claim
74 words
An image processing apparatus comprising: (a) means for amplifying an input image signal with a predetermined gain; (b) field cyclic noise reduction means for reducing a noise component of said amplifying means, said field cyclic noise reduction means reducing noise by combining two successive field image signals, in a ratio corresponding to a first parameter; and (c) means for controlling the first parameter in accordance with a second parameter, corresponding to said amplifying means.
Claim 22
Dependent Claim
60 words
An image processing apparatus according to claim 16, wherein said field cyclic noise reduction means includes a field memory for storing the input image signal amplified by said amplifying means and addition means for adding the image signal stored in said field memory and an image signal not stored in said field memory, in the ratio corresponding to the parameter.
Claim 23
Dependent Claim
18 words
An image processing apparatus according to claim 16, further comprising: (d) means for generating the input image signal.
Claim 24
Dependent Claim
15 words
An image processing apparatus according to claim 18, wherein said generating means comprises a CCD.
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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) | 1995-08-18 | 1996-02-17 | 1996-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-08-18 | 2000-02-17 | 2000-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-08-18 | 2004-02-17 | 2004-08-18 | $7700.00 | Window Closed / Lapsed |