Title:
IMAGE SIGNAL OUTPUT DEVICE FOR PRINTING
Document Type and Number:
Japanese Patent JPH01163068
Kind Code:
A
Abstract:
PURPOSE:To reduce interpolation noise and enhance image quality of, particularly, slant lines, by inserting a low-pass filter having such interpolation characteristics as to reproduce an continuous signal which has been sampled without any interpolation noise, between a digital filter and a binary coding device. CONSTITUTION:For pixel data inputted synchronously with a pixel clock signal for printing a pixel, a signal is outputted synchronously with a clock signal having a frequency of an integer times the frequency of the pixel clock signal. Next, an output from a digital filter 101 is smoothed by a low-pass filter 104, and an output from the filter 104 is binary coded by a binary coding device 102. The spatial spreading characteristics of a printer 103 have no spreading in the direction of continuous printing and o-th order interpolation characteristic in other directions. As a result, the printer 103 capable of continuously printing horizontally has no field of view for the pixel, and a black part is printed at an arbitrary position. Therefore, the width of a line can be made relatively uniform, and higher image quality can be contrived.
Inventors:
KOBAYASHI SHINYA
Application Number:
JP23256187A
Publication Date:
June 27, 1989
Filing Date:
September 18, 1987
Export Citation:
Assignee:
HITACHI LTD
HITACHI KOKI KK
HITACHI KOKI KK
International Classes:
B41J2/44; H04N1/393; H04N1/40; H04N1/409; (IPC1-7): B41J3/00; H04N1/40
Domestic Patent References:
| JPS6145675A | 1986-03-05 | |||
| JPS554195A | 1980-01-12 |
Attorney, Agent or Firm:
Masami Akimoto
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