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US4884128A Expired / Lapsed US ⏱️ 0.0 years remaining

Signal processing apparatus with independent gain control for chrominance and color signals

Assignee: Canon Inc
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Filing: 1989-03-20
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Granted: 1989-11-28
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Expires: 2009-03-20
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Abstract

Abstract A signal processing apparatus comprising: first automatic gain controls for automatically controlling gains of a plurality of chrominance signals and outputting the result to a process circuit; circuiting for dot-sequencing the chrominance signals before the first automatic gain controls; and second automatic gain controls for automatically controlling the gain of the signals which had been dot-sequenced, wherein a video signal is obtained from the outputs of the first and second automatic gain controls. An image pickup apparatus for use in this signal processing apparatus is also provided.

Inventors

  • 👤 Teruo Hieda

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 13:58
CPC Classifications
H; H04; H04N; H04N23/00; H04N23/70; H04N23/76; H04N23/80; H04N23/84; H04N23/88; H04N9/00; H04N9/64; H04N9/68

Claims Analysis

Total Claims: 35
Claim 1
Independent Claim 71 words
A signal processing apparatus comprising: (a) first automatic gain control means for automatically controlling gains of a plurality of color signals; (b) chroma signal forming means for forming chroma signals using color signals whose gains are automatically controlled by said first automatic gain control means; (c) high-band luminance signal forming means for dot sequencing said plurality of color signals whose gains are not controlled by said first automatic gain control means.
Claim 2
Dependent Claim 71 words
A signal processing apparatus comprising: (a) first automatic gain control means for automatically controlling gains of a plurality of color signals; (b) chroma signal forming means for forming chroma signals using color signals whose gains are automatically controlled by said first automatic gain control means; (c) high-band luminance signal forming means for dot sequencing said plurality of color signals whose gains are not controlled by said first automatic gain control means.
Claim 3
Dependent Claim 22 words
A signal processing apparatus according to claim 1, wherein said high-band luminance signal forming means is means for forming a luminance signal.
Claim 4
Dependent Claim 33 words
A signal processing apparatus according to claim 1, further comprising: (d) second automatic gain control means for automatically controlling a gain of a dot-sequenced signal formed by said high-band luminance signal forming means.
Claim 5
Dependent Claim 25 words
A signal processing apparatus according to claim 3, further comprising: control means for controlling the operations of said first and second automatic gain control means.
Claim 6
Dependent Claim 25 words
A signal processing apparatus according to claim 1, wherein said first automatic gain control means has a frequency characteristic suited for a chrominance signal band.
Claim 7
Dependent Claim 25 words
A signal processing apparatus according to claim 3, wherein said second automatic gain control means has a frequency characteristic suited for a luminance signal band.
Claim 8
Dependent Claim 28 words
A signal processing apparatus according to claim 4, wherein said control means comprises means for limiting gain control ranges of said first and second automatic gain control means.
Claim 9
Dependent Claim 28 words
A signal processing apparatus according to claim 7, wherein said control means sets the gains of said first and second automatic gain control means to the same value.
Claim 10
Dependent Claim 44 words
A signal processing apparatus according to claim 4, wherein said control means comprises means for detecting the level of said dot-sequenced, gain-controlled signal and controlling the gain of said first and second automatic gain control means such that said level becomes a predetermined level.
Claim 11
Dependent Claim 36 words
A signal processing apparatus according to claim 1, further comprising: (d) output means for controlling the levels of said plurality of color signals and outputting resulting level-controlled color signals to said high-band luminance signal forming means.
Claim 12
Dependent Claim 33 words
A signal processing apparatus according to claim 10, further comprising: (e) means for controlling said output means such that a predetermined relation is obtained among the levels of said plurality of color signals.
Claim 13
Dependent Claim 39 words
A signal processing apparatus according to claim 11, wherein said control means includes: means for generating color difference signals from said chroma signals; and means for controlling said output means such that said color difference signals become predetermined levels.
Claim 14
Dependent Claim 26 words
A signal processing apparatus according to claim 10, wherein said output means is means for controlling the levels of the color signals in a stepwise manner.
Claim 15
Dependent Claim 92 words
An image pickup apparatus comprising: (a) image pickup means for generating a plurality of color signals; (b) first automatic gain control means for automatically controlling gains of said plurality of color signals generated from said image pickup means; (c) means for dot-sequencing the color signals whose gains are not controlled by said automatic gain control means; (d) second automatic gain control means for automatically controlling a gain of said dot-sequenced signals; and (e) processing means for the signals which were automatically gain controlled by said first and second automatic gain control means.
Claim 16
Dependent Claim 92 words
An image pickup apparatus comprising: (a) image pickup means for generating a plurality of color signals; (b) first automatic gain control means for automatically controlling gains of said plurality of color signals generated from said image pickup means; (c) means for dot-sequencing the color signals whose gains are not controlled by said automatic gain control means; (d) second automatic gain control means for automatically controlling a gain of said dot-sequenced signals; and (e) processing means for the signals which were automatically gain controlled by said first and second automatic gain control means.
Claim 17
Dependent Claim 18 words
An image pickup apparatus according to claim 14, wherein said dot-sequencing means is for forming a luminance signal.
Claim 18
Dependent Claim 25 words
An image pickup apparatus according to claim 15, further comprising: control means for controlling the operations of said first and second automatic gain control means.
Claim 19
Dependent Claim 25 words
An image pickup apparatus according to claim 14, wherein said first automatic gain control means has a frequency characteristic suited for a chrominance signal band.
Claim 20
Dependent Claim 25 words
An image pickup apparatus according to claim 14, wherein said second automatic gain control means has a frequency characteristic suited for a luminance signal band.
Claim 21
Dependent Claim 28 words
An image pickup apparatus according to claim 16, wherein said control means comprises means for limiting gain control ranges of said first and second automatic gain control means.
Claim 22
Dependent Claim 43 words
An image pickup apparatus according to claim 16, wherein said control means comprises means for detecting the level of said dot-sequenced signals and controlling the gains of said first and second automatic gain control means such that said level becomes a predetermined level.
Claim 23
Dependent Claim 69 words
A signal processing apparatus comprising: (a) supplying means for supplying a plurality of color signals; (b) dot-sequencing means for generating a high-band luminance signal by dot-sequencing said plurality of color signals; (c) automatic gain control means for controlling a level of said high-band luminance signal so as to become a predetermined level; and (d) means for nonlinearly converting the signal which was controlled by said automatic gain control means.
Claim 24
Dependent Claim 69 words
A signal processing apparatus comprising: (a) supplying means for supplying a plurality of color signals; (b) dot-sequencing means for generating a high-band luminance signal by dot-sequencing said plurality of color signals; (c) automatic gain control means for controlling a level of said high-band luminance signal so as to become a predetermined level; and (d) means for nonlinearly converting the signal which was controlled by said automatic gain control means.
Claim 25
Dependent Claim 28 words
A signal processing apparatus according to claim 21, further comprising: (e) clamp means for clamping said high-band luminance signal which was level-controlled by said automatic gain control means.
Claim 26
Dependent Claim 31 words
A signal processing apparatus according to claim 21, wherein said nonlinearly converting means comprises means for compressing the level of the signal which was controlled by said automatic gain control means.
Claim 27
Dependent Claim 23 words
A signal processing apparatus according to claim 21, wherein said supplying means comprises image pickup means for generating said plurality of color signals.
Claim 28
Dependent Claim 16 words
A signal processing apparatus according to claim 24, wherein said image pickup means is a CCD.
Claim 29
Dependent Claim 51 words
A signal processing apparatus according to claim 21, wherein said automatic gain control means includes: means for leveling the signal which was dot-sequenced by said dot-sequencing means; and means for controlling the level of said dot-sequenced signal which was leveled by said leveling means so as to become a predetermined level.
Claim 30
Dependent Claim 93 words
A signal processing apparatus comprising: (a) first control means for controlling such that a predetermined relation is obtained among levels of a plurality of color signals; (b) means for dot-sequencing the color signals which were level-controlled by said first control means; (c) means for respectively processing the plurality of color signals which are not level-controlled by said first control means; and (d) second control means for controlling the levels of said plurality of color signals which were processed by said processing means, wherein frequency characteristics of said first and second control means differ.
Claim 31
Dependent Claim 93 words
A signal processing apparatus comprising: (a) first control means for controlling such that a predetermined relation is obtained among levels of a plurality of color signals; (b) means for dot-sequencing the color signals which were level-controlled by said first control means; (c) means for respectively processing the plurality of color signals which are not level-controlled by said first control means; and (d) second control means for controlling the levels of said plurality of color signals which were processed by said processing means, wherein frequency characteristics of said first and second control means differ.
Claim 32
Dependent Claim 28 words
A signal processing apparatus according to claim 27, wherein said first control means has the frequency characteristic of a higher band than that of said second control means.
Claim 33
Dependent Claim 16 words
A signal processing apparatus according to claim 27, wherein said processing means includes a clamp circuit.
Claim 34
Dependent Claim 18 words
A signal processing apparatus according to claim 27, wherein said dot-sequencing means is for forming a luminance signal.
Claim 35
Dependent Claim 50 words
A signal processing apparatus according to claim 27, further comprising: (e) means for generating color difference signals from said plurality of color signals which were processed by said processing means; and (f) means for driving said first and second control means such that said color difference signals become predetermined levels.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-11-27 1993-05-29 1993-11-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-11-27 1997-05-29 1997-11-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-11-27 2001-05-29 2001-11-28 $7700.00 Window Closed / Lapsed

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