Facsimile and static presentation processing – Static presentation processing – Attribute control
Patent
1983-11-30
1987-05-05
Groody, James J.
Facsimile and static presentation processing
Static presentation processing
Attribute control
358 80, 358280, 358283, 358284, H04N 146, H04N 140, G03F 308
Patent
active
046636625
ABSTRACT:
A picture signal processing circuit for use in a picture reproducing apparatus, wherein a picture to be copied is optically scanned by a line image sensor to provide picture signals for each of the plural picture elements of the picture. A detector circuit is arranged to detect a local variation in the density of the picture based on a convolution operation on picture signals of a two-dimensional picture-element array to produce a local density variation detection signal which represents a high frequency component of the input signal. The picture-element array being detected is shifted by one picture element in a scanning direction during optical scanning of the picture. A signal processor circuit is responsive to the local density variation detection signal to switch between a simple binarization processing using single threshold data and a dithering binarization processing using dither matrix threshold data for the picture signal to be applied to a printer. With this arrangement, line pictures, character pictures or the like are reproduced with binary signals and continuous tone pictures are reproduced with dithered signals.
REFERENCES:
patent: 3937878 (1976-02-01), Judice
patent: 4127871 (1978-11-01), Sakamoto
patent: 4194221 (1980-03-01), Stoffel
patent: 4251837 (1981-02-01), Janeway, III
patent: 4288821 (1981-09-01), Lavallee et al.
patent: 4485408 (1984-11-01), Kamizyo et al.
patent: 4495522 (1985-01-01), Matsunawa et al.
patent: 4517605 (1985-05-01), Yokomizo
patent: 4547811 (1985-10-01), Ochi et al.
patent: 4554593 (1985-11-01), Fox et al.
patent: 4556916 (1985-12-01), Matsunawa
patent: 4586089 (1986-04-01), Nakazato et al.
Schindler, H. R., et al., "Optical Scanning of Continuous-Tone and Line Documents with Spatial Frequency Separation for Improved Data Handling and Compaction", IBM Technical Disclosure Bulletin, vol. 20, No. 12, May 1978, pp. 5416-5421.
Brandley, C. R., "Pseudo-Halftone Generation", IBM Technical Disclosure Bulletin, vol. 20, No. 4, Sep. 1977.
Hosaka Yasuo
Miura Shuzo
Sekizawa Hidekazu
Yamada Kiyoshi
Groody James J.
Svihla Randall S.
Tokyo Shibaura Denki Kabushiki Kaisha
LandOfFree
Picture signal processing system featuring simple or dithering b does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Picture signal processing system featuring simple or dithering b, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Picture signal processing system featuring simple or dithering b will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2401430