US5446504A
Expired / Lapsed
US
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Image signal processing apparatus having function for compressing dynamic range and correcting color saturation
Assignee: Olympus Corp
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Filing: 1994-03-14
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Granted: 1995-08-29
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Expires: 2014-03-14
Abstract
Abstract An input section receives an image signal including signals related to colors to output at least a luminance signal component of the image signal. A compressing section compresses the dynamic range of the luminance signal component from the input section. A setting section obtains a compression coefficient from a relationship between the luminance signal component whose dynamic range is compressed by the compressing section and the luminance signal component from the input section. An operating section executes an operation for compressing dynamic ranges of the signals related to colors included in the image signal in accordance with the compression coefficient obtained by the setting section. A correcting section substantially corrects the color saturation of the signals related to a color included in the image signal while preserving the luminance of the image signal such that the color saturation is more intensively suppressed as the luminance becomes lower.
Inventors
- 👤 Tohru Wada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:54
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/64; H04N9/68
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
140 words
An image signal processing apparatus comprising: input means for inputting an image signal including signals related to colors, said input means including means for outputting a luminance signal in the image signal; dynamic range compressing means for compressing a dynamic range of the luminance signal from said input means; compression coefficient setting means for obtaining a compression coefficient from a relationship between an output from said dynamic range compressing means and the luminance signal from said input means; operating means for executing an operation for compressing dynamic ranges of the signals related to colors in accordance with the compression coefficient from said compression coefficient setting means; and color saturation correcting means for substantially correcting color saturation of the signals related to colors of one of a signal input to said operating means and a signal output from said operating means.
Claim 2
Dependent Claim
140 words
An image signal processing apparatus comprising: input means for inputting an image signal including signals related to colors, said input means including means for outputting a luminance signal in the image signal; dynamic range compressing means for compressing a dynamic range of the luminance signal from said input means; compression coefficient setting means for obtaining a compression coefficient from a relationship between an output from said dynamic range compressing means and the luminance signal from said input means; operating means for executing an operation for compressing dynamic ranges of the signals related to colors in accordance with the compression coefficient from said compression coefficient setting means; and color saturation correcting means for substantially correcting color saturation of the signals related to colors of one of a signal input to said operating means and a signal output from said operating means.
Claim 3
Dependent Claim
127 words
An apparatus according to claim 1, wherein: said input means includes a matrix circuit for receiving chrominance signals to generate at least a luminance signal, said dynamic range compressing means compresses a dynamic range of the luminance signal from said matrix circuit, said compression coefficient setting means obtains a compression coefficient from a relationship between an output from said dynamic range compressing means and the luminance signal from said matrix circuit, said operating means executes an operation for compressing a dynamic range of each chrominance signal in accordance with the compression coefficient from said compression coefficient setting means, and said color saturation correcting means is coupled to said operating means and corrects color saturation of each chrominance signal whose dynamic range is compressed by said operating means.
Claim 4
Dependent Claim
118 words
An apparatus according to claim 1, wherein: said input means includes a matrix circuit for receiving chrominance signals to generate at least a luminance signal, said dynamic range compressing means compresses a dynamic range of the luminance signal from said matrix circuit, said compression coefficient setting means obtains a compression coefficient from a relationship between an output from said dynamic range compressing means and the luminance signal from said matrix circuit, said color saturation correcting means corrects color saturation of each chrominance signal, and said operating means compresses a dynamic range of each chrominance signal, whose color saturation is corrected by said color saturation correcting means, in accordance with the compression coefficient from said compression coefficient setting means.
Claim 5
Dependent Claim
130 words
An apparatus according to claim 1, wherein: said input means includes a matrix circuit for receiving chrominance signals to generate at least color difference signals and a luminance signal, said dynamic range compressing means compresses a dynamic range of the luminance signal from said matrix circuit, said compression coefficient setting means obtains a compression coefficient from a relationship between an output from said dynamic range compressing means and the luminance signal from said matrix circuit, said operating means executes an operation for compressing a dynamic range of each color difference signal from said matrix circuit in accordance with the compression coefficient from said compression coefficient setting means, and said color saturation correcting means corrects color saturation of each color difference signal whose dynamic range is compressed by said operating means.
Claim 6
Dependent Claim
128 words
An apparatus according to claim 1, wherein: said input means includes a matrix circuit for receiving chrominance signals to generate at least color difference signals and a luminance signal, said dynamic range compressing means compresses a dynamic range of the luminance signal from said matrix circuit, said compression coefficient setting means obtains a compression coefficient from a relationship between an output from said dynamic range compressing means and the luminance signal from said matrix circuit, said color saturation correcting means corrects color saturation of each color difference signal from said matrix circuit, and said operating means compresses a dynamic range of each color difference signal, whose color saturation is corrected by said color saturation correcting means, in accordance with the compression coefficient from said compression coefficient setting means.
Claim 7
Independent Claim
45 words
An apparatus according to any one of claims 1 to 5, wherein said color saturation correcting means adaptively sets a correction amount of the color saturation in accordance with a magnitude of a compression ratio of the dynamic range by said dynamic range compressing means.
Claim 8
Independent Claim
39 words
An apparatus according to any one of claims 1 to 5, wherein said color saturation correcting means adaptively sets a correction amount of the color saturation in accordance with a magnitude of each pixel signal of the image signal.
Claim 9
Independent Claim
56 words
An apparatus according to any one of claims 1 to 5, wherein said color saturation correcting means adaptively sets a correction amount of the color saturation in accordance with a magnitude of each pixel signal of the image signal and a magnitude of a compression ratio of the dynamic range by said dynamic range compressing means.
Claim 10
Independent Claim
47 words
An apparatus according to any one of claims 1 to 5, wherein said color saturation correcting means adaptively sets a correction amount of the color saturation of each pixel of the image signal in accordance with a magnitude of an output from said compression coefficient setting means.
Claim 11
Dependent Claim
119 words
An image signal processing apparatus comprising: input means for inputting an image signal including signals related to colors, said input means including means for outputting a luminance signal in the image signal; dynamic range compressing means for compressing a dynamic range of the luminance signal from said input means; compression coefficient setting means for obtaining a compression coefficient from a relationship between an output from said dynamic range compressing means and the luminance signal from said input means; coefficient converting means for converting an output from said compression coefficient setting means into a coefficient including a color saturation correction coefficient; and operating means for operating on an output from said coefficient converting means and the signals related to colors.
Claim 12
Dependent Claim
119 words
An image signal processing apparatus comprising: input means for inputting an image signal including signals related to colors, said input means including means for outputting a luminance signal in the image signal; dynamic range compressing means for compressing a dynamic range of the luminance signal from said input means; compression coefficient setting means for obtaining a compression coefficient from a relationship between an output from said dynamic range compressing means and the luminance signal from said input means; coefficient converting means for converting an output from said compression coefficient setting means into a coefficient including a color saturation correction coefficient; and operating means for operating on an output from said coefficient converting means and the signals related to colors.
Claim 13
Dependent Claim
23 words
An apparatus according to claim 10, wherein said input means includes a matrix circuit for generating color difference signals and a luminance signal.
Claim 14
Dependent Claim
41 words
An apparatus according to claim 10 or 11, wherein said coefficient converting means adaptively sets a correction coefficient of the color saturation in accordance with a magnitude of a compression ratio of the dynamic range by said dynamic range compressing means.
Claim 15
Dependent Claim
35 words
An apparatus according to claim 10 or 11, wherein said coefficient converting means adaptively sets a correction coefficient of the color saturation in accordance with a magnitude of each pixel signal of the image signal.
Claim 16
Dependent Claim
52 words
An apparatus according to claim 10 or 11, wherein said coefficient converting means adaptively sets a correction coefficient of the color saturation in accordance with a magnitude of each pixel signal of the image signal and a magnitude of a compression ratio of the dynamic range by said dynamic range compressing means.
Claim 17
Dependent Claim
43 words
An apparatus according to claim 10 or 11, wherein said coefficient converting means adaptively sets a correction coefficient of the color saturation of each pixel of the image signal in accordance with a magnitude of an output from said compression coefficient setting means.
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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) | 1998-08-28 | 1999-02-27 | 1999-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-08-28 | 2003-02-27 | 2003-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-08-28 | 2007-02-27 | 2007-08-29 | $7700.00 | Window Closed / Lapsed |