JPS57123766A - Density gradation processing system of digital facsimile - Google Patents

Density gradation processing system of digital facsimile

Info

Publication number
JPS57123766A
JPS57123766A JP56009375A JP937581A JPS57123766A JP S57123766 A JPS57123766 A JP S57123766A JP 56009375 A JP56009375 A JP 56009375A JP 937581 A JP937581 A JP 937581A JP S57123766 A JPS57123766 A JP S57123766A
Authority
JP
Japan
Prior art keywords
image information
outputted
reception side
threshold level
comparator
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.)
Granted
Application number
JP56009375A
Other languages
English (en)
Other versions
JPS6149873B2 (ja
Inventor
Mutsuo Ogawa
Noboru Murayama
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 JP56009375A priority Critical patent/JPS57123766A/ja
Priority to US06/341,256 priority patent/US4504115A/en
Priority to DE19823202155 priority patent/DE3202155A1/de
Publication of JPS57123766A publication Critical patent/JPS57123766A/ja
Publication of JPS6149873B2 publication Critical patent/JPS6149873B2/ja
Granted 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
    • H04N1/41—Bandwidth or redundancy reduction
    • H04N1/4105—Bandwidth or redundancy reduction for halftone screened pictures
    • 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
    • H04N1/405—Halftoning, i.e. converting the picture signal of a continuous-tone original into a corresponding signal showing only two levels
    • H04N1/4055—Halftoning, i.e. converting the picture signal of a continuous-tone original into a corresponding signal showing only two levels producing a clustered dots or a size modulated halftone pattern

Landscapes

  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Facsimile Image Signal Circuits (AREA)
  • Image Processing (AREA)
JP56009375A 1981-01-23 1981-01-23 Density gradation processing system of digital facsimile Granted JPS57123766A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
JP56009375A JPS57123766A (en) 1981-01-23 1981-01-23 Density gradation processing system of digital facsimile
US06/341,256 US4504115A (en) 1981-01-23 1982-01-21 Digital facsimile communication system capable of representing tone differences
DE19823202155 DE3202155A1 (de) 1981-01-23 1982-01-23 Digitales faksimile-uebertragungssystem

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP56009375A JPS57123766A (en) 1981-01-23 1981-01-23 Density gradation processing system of digital facsimile

Publications (2)

Publication Number Publication Date
JPS57123766A true JPS57123766A (en) 1982-08-02
JPS6149873B2 JPS6149873B2 (ja) 1986-10-31

Family

ID=11718705

Family Applications (1)

Application Number Title Priority Date Filing Date
JP56009375A Granted JPS57123766A (en) 1981-01-23 1981-01-23 Density gradation processing system of digital facsimile

Country Status (3)

Country Link
US (1) US4504115A (ja)
JP (1) JPS57123766A (ja)
DE (1) DE3202155A1 (ja)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59143471A (ja) * 1983-02-04 1984-08-17 Shinko Electric Co Ltd 階調印字機能付プリンタ

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA1192997A (en) * 1982-11-30 1985-09-03 Northern Telecom Limited Bilevel coding of colour video signals
US4700234A (en) * 1983-08-30 1987-10-13 Canon Kabushiki Kaisha Image processing system
US4654721A (en) * 1985-04-12 1987-03-31 International Business Machines Corporation System for reproducing multi-level digital images on a bi-level printer of fixed dot size
US4673987A (en) * 1985-04-22 1987-06-16 Ibm Corporation Compressed block code for facsimile transmission
JPH049417Y2 (ja) * 1985-07-16 1992-03-09
JPS6277637A (ja) * 1985-10-01 1987-04-09 Seiko Instr & Electronics Ltd カラ−ハ−ドコピ−装置
US5175807A (en) * 1986-12-04 1992-12-29 Quantel Limited Video signal processing with added probabilistic dither
NL8902654A (nl) * 1988-11-24 1990-06-18 Oce Nederland Bv Werkwijze en inrichting voor het verwerken en weergeven van beeldinformatie.

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5223207A (en) * 1975-08-16 1977-02-22 Oki Electric Ind Co Ltd Method of coding pictures
JPS53139422A (en) * 1977-05-12 1978-12-05 Matsushita Graphic Commun Syst Inc Multi-gradation recording device

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5751310B2 (ja) * 1972-06-07 1982-11-01
JPS545613A (en) * 1977-06-16 1979-01-17 Kokusai Denshin Denwa Co Ltd Facsimile signal encoding system
GB2016872B (en) * 1978-02-23 1982-08-25 Nippon Electric Co Digital facsimile transmission system for screened pictures
JPS54124619A (en) * 1978-03-22 1979-09-27 Fuji Xerox Co Ltd Optical image reading method
US4353096A (en) * 1978-10-05 1982-10-05 Nippon Electric Co., Ltd. Digital facsimile system to band-compress half-tone picture signals
JPS5563173A (en) * 1978-11-06 1980-05-13 Ricoh Co Ltd Picture signal processing system
US4214277A (en) * 1979-02-02 1980-07-22 Xerox Corporation Halftone implementation apparatus
US4340912A (en) * 1980-09-15 1982-07-20 Am International, Inc. Random screen generator apparatus for producing halftone images
JPS5778275A (en) * 1980-11-01 1982-05-15 Canon Inc Signal processing method
US4420771A (en) * 1981-02-09 1983-12-13 Bell Telephone Laboratories, Incorporated Technique for encoding multi-level signals
GB2101836B (en) * 1981-07-18 1985-02-20 Linotype Paul Ltd Method for encoding image data
BE889996A (nl) * 1981-08-18 1981-12-16 Belge Lampes Mat Electr Mble Facsimile overdrachtsinrichting

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5223207A (en) * 1975-08-16 1977-02-22 Oki Electric Ind Co Ltd Method of coding pictures
JPS53139422A (en) * 1977-05-12 1978-12-05 Matsushita Graphic Commun Syst Inc Multi-gradation recording device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59143471A (ja) * 1983-02-04 1984-08-17 Shinko Electric Co Ltd 階調印字機能付プリンタ

Also Published As

Publication number Publication date
DE3202155C2 (ja) 1989-11-30
DE3202155A1 (de) 1982-09-23
US4504115A (en) 1985-03-12
JPS6149873B2 (ja) 1986-10-31

Similar Documents

Publication Publication Date Title
US4091424A (en) Facsimile compression system
US4468704A (en) Adaptive thresholder
JPS642475A (en) Image processing method and device therefor
KR920014215A (ko) 고효율 코딩 장치
US6614473B1 (en) Image sensor having a margin area, located between effective pixel and optical black areas, which does not contribute to final image
JPS57123766A (en) Density gradation processing system of digital facsimile
US4796092A (en) Image processing with compression encoding
EP0083247A2 (en) Facsimile data converting system
US5282059A (en) Facsimile apparatus comprising converting means for converting binary image data into multi-value image data
JPS55162179A (en) Picture processing method
JPS58215869A (ja) グレ−スケ−ル映像デ−タを縮少する方法
EP0195925A2 (en) Method for converting image gray levels
KR960014317B1 (ko) 화상 해상도 변환 장치
JPS6213165A (ja) 画信号符号化方式
JPH054876B2 (ja)
JPS58136173A (ja) デイザ処理装置
US5181126A (en) Reading device for facsimile apparatus
JPH0322675A (ja) 階調情報圧縮方式
JPS62200873A (ja) フアクシミリ装置
JPH04270561A (ja) 画像処理装置
Holladay A Performance Evaluation of LZ and CCITT Compression Techniques
JPS5948589B2 (ja) 画像信号の２値化変換回路
KR940001379Y1 (ko) 팩시밀리의 화신호 처리장치
JPS57146122A (en) Discriminating method for intermediate tone region
JPH067626Y2 (ja) 画情報読取装置