JPS561667A - Gamma correcting system for picture input/output device - Google Patents

Gamma correcting system for picture input/output device

Info

Publication number
JPS561667A
JPS561667A JP7740079A JP7740079A JPS561667A JP S561667 A JPS561667 A JP S561667A JP 7740079 A JP7740079 A JP 7740079A JP 7740079 A JP7740079 A JP 7740079A JP S561667 A JPS561667 A JP S561667A
Authority
JP
Japan
Prior art keywords
gate
prom5
density
sent
density level
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP7740079A
Other languages
Japanese (ja)
Inventor
Morizumi Kurose
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ricoh Co Ltd
Original Assignee
Ricoh Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ricoh Co Ltd filed Critical Ricoh Co Ltd
Priority to JP7740079A priority Critical patent/JPS561667A/en
Publication of JPS561667A publication Critical patent/JPS561667A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N1/00—Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
    • H04N1/40—Picture signal circuits
    • H04N1/407—Control or modification of tonal gradation or of extreme levels, e.g. background level
    • H04N1/4072—Control or modification of tonal gradation or of extreme levels, e.g. background level dependent on the contents of the original

Landscapes

  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Facsimile Image Signal Circuits (AREA)

Abstract

PURPOSE:To secure the simple and quick operation when the setting is altered for the density correction function, by providing several PROMs storing preveiously the gamma correction value according to the density and then using these PROMs selectively. CONSTITUTION:When mode change-over switch SW is set to the scan mode, gates G1-G3 are opened to form the circuit consisting of scanner 1 A/Dconverter 3 gate G1 gate G2 gate G7 PROM5 gate G3 interference 6 each. As a result, the digitized density level value of each picture element sent from converter 3 is sent to PROM5, and the contents storing the gamma correction value prviously according to the address is called out to be delivered to external unit 7 from interface 6. When switch SW is set under the plot mode, gates G4-G6 are opened to form the circuit consisting of interface 6 gate G5 gate G7 PROM5 gate G6 gate G4 D/A converter 4 plotter 2 each. And the optimum adjustment is given to the density level of the input picture, and the adjusted density level is sent to plotter 2 to reproduce a high-quality picture.
JP7740079A 1979-06-19 1979-06-19 Gamma correcting system for picture input/output device Pending JPS561667A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP7740079A JPS561667A (en) 1979-06-19 1979-06-19 Gamma correcting system for picture input/output device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP7740079A JPS561667A (en) 1979-06-19 1979-06-19 Gamma correcting system for picture input/output device

Publications (1)

Publication Number Publication Date
JPS561667A true JPS561667A (en) 1981-01-09

Family

ID=13632840

Family Applications (1)

Application Number Title Priority Date Filing Date
JP7740079A Pending JPS561667A (en) 1979-06-19 1979-06-19 Gamma correcting system for picture input/output device

Country Status (1)

Country Link
JP (1) JPS561667A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58161572A (en) * 1982-03-19 1983-09-26 Fuji Xerox Co Ltd Heat-sensitive recorder
JPS6074772A (en) * 1983-09-29 1985-04-27 Matsushita Electric Ind Co Ltd Quantizing method of multi-value picture information
JPS61242465A (en) * 1985-04-19 1986-10-28 Matsushita Graphic Commun Syst Inc Facsimile equipment provided with automatic dial function
JPH0522584A (en) * 1991-07-09 1993-01-29 Canon Inc Color image recording method and apparatus

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58161572A (en) * 1982-03-19 1983-09-26 Fuji Xerox Co Ltd Heat-sensitive recorder
JPS6074772A (en) * 1983-09-29 1985-04-27 Matsushita Electric Ind Co Ltd Quantizing method of multi-value picture information
JPS61242465A (en) * 1985-04-19 1986-10-28 Matsushita Graphic Commun Syst Inc Facsimile equipment provided with automatic dial function
JPH0522584A (en) * 1991-07-09 1993-01-29 Canon Inc Color image recording method and apparatus

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