Title:
DATA REWRITING APPARATUS OF VIDEO PRINTER
Document Type and Number:
Japanese Patent JPH01133745
Kind Code:
A
Abstract:
PURPOSE:To add a function for inserting a character in a printed image on a digital base, by reading the drive signal of a thermal head by one of the change-over switches provided to the thermal head on the input side thereof and reading the switch signal written in a line memory by the other change-over switch to control the switches. CONSTITUTION:An input video signal (static image) is converted to R-, G- and B-signals by a decoder and converted to ink colors Cy, Mg, I/e by a complementary color converting circuit 3. The data sampled by an A/D converter 5 through a switch 4 is written in a line memory 6. For example, when a 2KX8 bit SRAM is used in the line memory and gradation data is set to 6-bit 64-gradation, since memory cells are left by 2 bits, one bit among them is utilized to write '1' in the address in a Y-direction desiring the rewriting of data, and '1' is read to change over a switch 22. The switch 22 is changed over so that the data from a gradation control circuit 7 is sent to a thermal head 8 at the time of '0' and the data from a switch 21 is sent thereto at the time of '1'. Data becomes a black or broken character based on whether the switch 21 is continued to Vcc or earth.
Inventors:
KIMURA HIROYUKI
OKI KATSUNORI
OKI KATSUNORI
Application Number:
JP29205887A
Publication Date:
May 25, 1989
Filing Date:
November 20, 1987
Export Citation:
Assignee:
HITACHI LTD
International Classes:
B41J2/525; B41J2/00; H04N1/46; H04N9/79; (IPC1-7): B41J3/00; H04N9/79
Attorney, Agent or Firm:
Katsuo Ogawa (1 person outside)