← Back to Patent Explorer
US4698690A Expired / Lapsed US ⏱️ 0.0 years remaining

Image signal processor

Assignee: Canon Inc
•
Filing: 1984-07-23
•
Granted: 1987-10-06
•
Expires: 2004-07-23
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An image signal processor capable of achieving an excellent image reproduction. The image signal processor has an input unit for entering analog video signals, and a converter for converting the analog video signals to digital video signals with a conversion factor which is changed according to the signal level, wherein binary video signals are formed based on the digital video signals from said converter.

Inventors

  • 👤 Hiroshi Tanioka

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 17:42
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/40; H04N1/407; H04N1/4072; H04N1/405; H04N1/4055

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 111 words
An image signal processor comprising: input means for entering an analog video signal representing a density of an image; means for converting the analog video signal fed from said input means to a digital video signal having a plurality of bits, said converting means having a plurality of analog-to-digital converters to which the analog video signal is applied on a parallel basis, said plurality of analog-to-digital converters being biased with mutually different reference voltage values so as to convert the analog video signal into the digital video signal on a non-linear characteristic basis; and processing means for performing processing for halftone reproduction on the digital video signal from said converting means.
Claim 2
Dependent Claim 111 words
An image signal processor comprising: input means for entering an analog video signal representing a density of an image; means for converting the analog video signal fed from said input means to a digital video signal having a plurality of bits, said converting means having a plurality of analog-to-digital converters to which the analog video signal is applied on a parallel basis, said plurality of analog-to-digital converters being biased with mutually different reference voltage values so as to convert the analog video signal into the digital video signal on a non-linear characteristic basis; and processing means for performing processing for halftone reproduction on the digital video signal from said converting means.
Claim 3
Dependent Claim 24 words
An image signal processor according to claim 1, wherein said processing means forms a binary video signal to be used for pseudo halftone reproduction.
Claim 4
Dependent Claim 25 words
An image signal processor according to claim 2 which further comprises recording means for recording on a recording medium based on the binary video signal.
Claim 5
Dependent Claim 49 words
An image signal processor according to claim 1, wherein said input means has reading means for reading photoelectrically an original image and outputting an analog video signal corresponding thereto, to be fed to said converting means as the analog video signal to be converted to the digital video signal.
Claim 6
Dependent Claim 24 words
An image signal process according to claim 1, wherein said processing means performs dither processing on the digital video signal from said converting means.
Claim 7
Dependent Claim 31 words
An image signal processor according to claim 1, wherein said plurality of analog-to-digital converters are operable to convert the analog video signal into the digit video signal with mutually different resolutions.
Claim 8
Dependent Claim 33 words
An image signal processor according to claim 1, wherein said plurality of analog-to-digital converters are operable to respectively convert the analog video signal within mutually different level ranges into the digital video signal.
Claim 9
Dependent Claim 33 words
An image signal processor according to claim 1, further comprising a laser beam printer for recording an image on a recording medium based on the digital video signal processed by said processing means.
Claim 10
Dependent Claim 108 words
An image signal processor comprising: input means for entering an analog video signal representing a density of an image; means for converting the analog video signal fed from said input means to a digital video signal having a plurality of bits, said converting means having a plurality of analog-to-digital converters to which the analog video signal is supplied on a parallel basis, said plurality of analog-to-digital converters being operable to convert the analog video signal within mutually different level ranges into the digital video signal with with mutually different resolutions; and processing means for performing processing for halftone reproduction on the digital video signal from said converting means.
Claim 11
Dependent Claim 108 words
An image signal processor comprising: input means for entering an analog video signal representing a density of an image; means for converting the analog video signal fed from said input means to a digital video signal having a plurality of bits, said converting means having a plurality of analog-to-digital converters to which the analog video signal is supplied on a parallel basis, said plurality of analog-to-digital converters being operable to convert the analog video signal within mutually different level ranges into the digital video signal with with mutually different resolutions; and processing means for performing processing for halftone reproduction on the digital video signal from said converting means.
Claim 12
Dependent Claim 24 words
An image signal processor according to claim 9, wherein said processing means forms a binary video signal to be used for pseudo halftone reproduction.
Claim 13
Dependent Claim 27 words
An image signal processor according to claim 10, which further comprises recording means for recording an image on a recording medium based on the binary video signal.
Claim 14
Dependent Claim 49 words
An image signal processor according to claim 9, wherein said input means has reading means for reading photoelectrically an original image and outputting an analog video signal corresponding thereto, to be fed to said converting means as the analog video signal to be converted to the digital video signal.
Claim 15
Dependent Claim 24 words
An image signal processor according to claim 9, wherein said processing means performs dither processing on the digital video signal from said converting means.
Claim 16
Dependent Claim 22 words
An image signal processor according to claim 9, wherein said plurality of analog-to-digital converters are biased with mutually different reference voltage values.
Claim 17
Dependent Claim 33 words
An image signal processor according to claim 9, further comprising a laser beam printer for recording an image on a recording medium based on the digital video signal processed by said processing means.

References Cited (Backward Citations)

US3723649A Cited
US4414581A Cited
US4475127A Cited
US4517605A Cited
US4495522A Cited
US4578712A Cited
US4578715A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-10-05 1991-04-06 1991-10-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-10-05 1995-04-06 1995-10-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-10-05 1999-04-06 1999-10-06 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag