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US4740844A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of changing magnification of image

Assignee: Ricoh Co Ltd
•
Filing: 1986-04-09
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Granted: 1988-04-26
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Expires: 2006-04-09
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Abstract

Abstract A method of applying magnification changing processing to an image in a digital copier or the like. The processing consists of subprocessing which is effected by operating optics of a scanner, and subprocessing which is effected by space filter processing of the kind using a threshold matrix. When digital video data read by the scanner on a pixel basis and quantized with respect to multiple levels are to be binarized by the space filter processing, the size of the threshold matrix is changed to roughly change the magnification. A delicate change of magnification is performed by the operation of the optics while the scanner reads the image.

Inventors

  • 👤 Tsuyoshi Yoshimura

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 04:21
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/387; H04N1/393; H04N1/40; H04N1/405; H04N1/4051; H04N1/4055

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 98 words
A method of varying a magnification of an image carried on a document, comprising the steps of: (a) scanning the image of the document by a scanner to read the image on a pixel basis; (b) while the scanner reads the image, operating optics of the scanner to vary the magnification; (c) quantizing magnification-varied video data with respect to multiple levels to produce digital video data; (d) binarizing the digital video data by space filter processing which uses a threshold matrix; and (e) during the binarizing step, changing a size of the threshold matrix to change the magnification.
Claim 2
Independent Claim 98 words
A method of varying a magnification of an image carried on a document, comprising the steps of: (a) scanning the image of the document by a scanner to read the image on a pixel basis; (b) while the scanner reads the image, operating optics of the scanner to vary the magnification; (c) quantizing magnification-varied video data with respect to multiple levels to produce digital video data; (d) binarizing the digital video data by space filter processing which uses a threshold matrix; and (e) during the binarizing step, changing a size of the threshold matrix to change the magnification.
Claim 3
Dependent Claim 20 words
A method as claimed in claim 1, wherein the space filter processing in step (d) uses a partial matrix method.
Claim 4
Dependent Claim 20 words
A method as claimed in claim 1, wherein the space filter processing in step (d) uses a density pattern method.

References Cited (Backward Citations)

US3837743A Cited
US4424534A Cited
US4423439A Cited
US4521812A Cited
US4496983A Cited
US4679096A Cited
US4651225A Cited
US4684979A Cited
US4633327A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-04-26 1991-10-26 1992-04-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-04-26 1995-10-26 1996-04-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-04-26 1999-10-26 2000-04-26 $7700.00 Window Closed / Lapsed

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