Picture printing device

• US 4,387,435 A
• Filed: 08/29/1980
• Issued: 06/07/1983
• Est. Priority Date: 09/03/1979
• Status: Expired due to Term

• Current Assignee: Fuji Xerox Company Limited (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Xerox Company Limited (Fujifilm Holdings Corporation)
• Inventors: Arai, Yoshio, Kataoka, Hiroyuki, Moriya, Yasumasa
• Primary Examiner(s): Krass, Errol A.
• Application Number:
  US06/182,727
• Time in Patent Office: 1,012 Days
• Field of Search: 364/515, 364/518, 364/571, 358/183, 358/280, 340/723, 340/727
• US Class Current: 358/1.6
• CPC Class Codes: H04N 1/3878 Skew detection or correction

Abstract

A picture printing device and method for printing pictures using a main scan and a sub scan. A first comparison means counts the number of picture elements in a main-scanning direction and compares that number with a first value preset in the first comparison means. A second comparison means counts the number of scanning lines in a sub-scanning direction and compares that number with a second value preset in the second comparison means. A printer records predetermined signals in response to combinations of the outputs of the first and second comparison means.

Claims

1. A picture printing device for printing pictures using a main scan and a sub scan and in which predetermined picture position data is simultaneously printed at predetermined coordinate positions with respect to main-scanning and sub-scanning start reference points comprising:

first comparison means for counting a number of picture elements in a main-scanning direction and comparing said number of picture elements thus counted with a first value preset in said first comparison means;

second comparison means for counting the number of scanning lines in a sub-scanning direction and comparing said number of scanning lines thus counted with a second value preset in said second comparison means;

means for printing and recording predetermined signals in response to combinations of outputs of said first comparison means and said second comparison means wherein the printing of said predetermined signals is accompanied by said predetermined picture position data, and means for utilizing said predetermined picture position data to correct the alignment of a re-read print output with respect to the horizontal and vertical axes of a recording medium.

2. A picture printing device for printing pictures using a main scan and a sub scan and in which predetermined picture position data is simultaneously printed at predetermined coordinate positions with respect to main-scanning and sub-scanning start reference points comprising:

a picture reading device producing a serial output signal representing a read picture, said picture reading device starting operation in response to a read start signal, and said picture reading device producing an operation complete signal and an output synchronization signal;

a reading mode flag flip-flop, said reading mode flag flip-flop being set to a first state by said read start signal and a second state by said operation complete signal;

a series-to-parallel converter receiving said serial output signal from said picture reading device as a data input signal, said series-to-parallel converter operating in response to said output synchronization signal produced by said picture reading device;

a first byte counter operatively coupled to count in response to said output synchronization signal from said picture reading device;

a printer, said printer starting operation in response to a print start signal, said printer producing an operation complete signal and a data reading synchronization signal;

a second byte counter operatively coupled to count in response to said data reading synchronization signal produced by said printer;

a first data selector, a carry output of said first byte counter being coupled to a first input of said first data selector and a carry output of said second byte counter being coupled to a second input of said first data selector, said first data selector operating in response to an output of said reading mode flag flip-flop;

a printing mode flag flip-flop, said printing mode flag flip-flop being set to a first state by said print start signal and to a second state by said operation completion signal produced by said printer;

a first OR gate having a first input coupled to an output of said printing mode flag flip-flop and a second input coupled to said output of said reading mode flag flip-flop;

a delay circuit having an input coupled to an output of said first data selector;

a memory address counter operatively coupled to count in response to an output of said delay circuit;

a central processing unit, said central processing unit having a read data bus, a write data bus, and a memory address bus, said central processing unit producing a write request signal and a read request signal;

a second data selector having a first input coupled to said output of said second byte counter and a second input coupled to said read request signal produced by said central processing unit, said data selector operating in response to said output of said printing mode flag flip-flop;

a third data selector having a first input coupled to said output of said first byte counter and a second input coupled to said write request signal produced by said central processing unit, said third data selector operating in response to said output of said reading mode flag flip-flop;

a fourth data selector having a first input port coupled to count outputs of said memory address counter and a second input port coupled to said memory address bus of said central processing unit, said fourth data selector operating in response to an output of said first OR gate;

a fifth data selector having a first input port coupled to outputs of said series-to-parallel converter and a second input port coupled to said write data bus of said central processing unit, said fifth data selector operating in response to said output of said reading mode flag flip-flop;

a main buffer memory having an address input port coupled to an output port of said fourth data selector, a data input port coupled to an output port of said fifth data selector, a write request input coupled to an output of said third data selector, a read request input coupled to an output of said second data selector, and an output data port coupled to said read data bus of said central processing unit;

a parallel-to-series converter having a data input port coupled to said read data bus of said central processing unit, said parallel-to-series converter operating in response to said output of said delay circuit and said data reading synchronization signal produced by said printer;

a set of AND gates having first inputs coupled to corresponding outputs of said parallel-to-series converter and outputs coupled to data inputs of said printer;

a column counter operatively coupled to count in response to said data reading synchronization signal produced by said printer, a first register for storing a first fixed digital number;

a first comparator having a first input port coupled to an output port of said line counter and a second input port coupled to outputs of said first register;

a line counter operatively coupled to count in response to a carry output of said column counter, said line counter producing a carry output signal coupled as an operation completion signal to said printer;

a second register for storing a second fixed digital number;

a second comparator having a first input port coupled to outputs of said line counter and a second input port coupled to outputs of said second register; and

a second OR gate having a first input coupled to a comparison output of said first comparator and a second input coupled to a comparison output of said second comparator, an output of said second OR gate being coupled to inputs of said AND gates.

4. The picture printing device of claim 2, further including means for utilizing said predetermined picture position data to correct the alignment of a re-read print output with respect to the horizontal and vertical axes of a recording medium.

3. A method for correcting the position of a re-read print output comprising the steps of:

determining the number of picture elements n_a between the intersection of an a-th scanning line and a reference line, and the intersection of a position data line and said a-th scanning line;

determining the number of picture elements n_b between the intersection of said reference line and a (a+N)-th scanning line and the intersection of said position data line and said (a+N)-th scanning line;

determining the amount of rotational deviation φ

between an original picture stand and said position data line in accordance with φ

=tan^-1 (n_a -n_b)/N;

correcting the angular deviation of said picture in accordance with the value φ

;

determining the number of picture elements corresponding to the distance between said reference line and said position data line;

determining the number of scanning lines corresponding to the distance between a second reference line perpendicular to the first-mentioned reference line and a position data line perpendicular to the first-mentioned position data line; and

correcting horizontal and vertical deviations in response to the determined number of picture elements corresponding to the distance between said first-mentioned reference line and said first-mentioned data line and said second-mentioned reference line and said second-mentioned position data line, respectively.