High-quality character generating system and method for use therein

• US 5,426,727 A
• Filed: 12/03/1993
• Issued: 06/20/1995
• Est. Priority Date: 01/20/1989
• Status: Expired due to Fees

• Current Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
• Original Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
• Inventors: Maeda, Masato, Sugiura, Masayuki
• Primary Examiner(s): Nguyen, Phu K,
• Application Number:
  US08/161,310
• Time in Patent Office: 564 Days
• Field of Search: 382/46, 382/56, 395/143, 395/144, 395/150, 395/151, 395/, 345/141, 345/142, 345/143, 345/144
• US Class Current: 345/467
• CPC Class Codes: G06T 11/20 Drawing from basic elements, e.g. lines or circles
• CPC Class Codes: G09G 5/24 Generation of individual character patterns
• CPC Class Codes: Y10S 345/947 Font character edge processing

Abstract

A character generation system, in which multiple operations are performed in parallel to achieve higher-speed processing, includes a circuit for converting character contour data into coordinate axis data, a circuit for generating dot data expressive of the contour from the coordinate axis data, a circuit for sorting the coordinate axis data in a prescribed sequence and a circuit for performing image drawing operations in correspondence with the sorted data. At least two of these circuits include sufficient channels to permit the performance of their designated functions in parallel. The required image drawing time is reduced by a decrease in the required number of accesses to a bit map using a polygon approach to character generation. The invention selects only the starting point and terminating point for its image drawing process out of the coordinates which form the polygon and draws a character on the bit map while generating the coordinates incremented by a predetermined value from the starting point to the terminating point. The invention also relates to a method for image drawing.

Claims

1. A high-quality character generating system comprising:

a first memory for storing outline fonts composed of character contour data;

coordinate converting means, connected to said first memory, for converting coordinates of said character contour data into vector coordinates;

contour coordinate generating means, connected to said coordinate converting means, for generating dot data corresponding to the contours of characters from said vector coordinates;

sorting means, connected to said contour coordinate generating means, for sorting the dot data output from the contour coordinate generating means according to prescribed rules to generate sorted data;

image drawing means, connected to said sorting means, for generating character data as dots from said sorted data; and

a second memory for storing the character data as dots corresponding to the output from the image drawing means;

wherein at least two of the coordinate converting means, the contour coordinate generating means, the sorting means, and the image drawing means each operate in parallel.

2. A high-quality character generating system as claimed in claim 1, wherein said contour coordinate generating means comprises:

input control means for storing vector coordinates received from said coordinate converting means;

coordinate calculating means for reading out coordinates for a starting point and an ending point, and calculating and generating straight line coordinates for a straight line connecting said starting point and said ending point;

straight line coordinate selecting means for selecting only those of said straight line coordinates defining said character contour;

corner coordinate selecting means for selecting corner coordinates defining a corner; and

output control means for outputting said straight line coordinates and corner coordinates to said sorting means.

9. A high-quality character generating system as claimed in claim 1, wherein said coordinate converting means includes at least one of:

means for effecting a reduction of said character;

means for effecting an enlargement of said character;

means for effecting an inclination of said character;

means for effecting a rotation of said character; and

means for effecting a horizontal shift of said character.

3. A high-quality character generating system comprising:

a first memory for storing character contour data;

contour coordinate generating means for generating character contour coordinates based on said character contour data;

coordinate selecting means for selecting ones of said character contour coordinates, so that an even number of the selected coordinates will be arranged in a direction of an image drawing axis;

image drawing means for generating further coordinates, incremented by a predetermined value in the direction of the image drawing axis, from selected coordinates in odd-number positions in the direction of the image drawing axis out of the selected coordinates, until the further coordinates so generated correspond to the selected coordinates in the even-number positions; and

a second memory for storing character data generated by said image drawing means;

wherein the specified character is drawn in correspondence with the selected and further coordinates from the odd-number position to the even-number position as generated by the image drawing means.

4. A high-quality character generating system as claimed in claim 3, wherein said contour coordinate generating means comprises:

input control means for storing said character contour data received from said first memory;

coordinate calculating means for reading out coordinates for a starting point and an ending point, and calculating and generating straight line coordinates for a straight line connecting said starting point and said ending point;

straight line coordinate selecting means for selecting only those of said straight line coordinates that define said character contour;

corner coordinate selecting means for selecting corner coordinates defining a corner; and

output control means for outputting said straight line coordinates and corner coordinates to said image drawing means.

5. A method of generating high-quality characters, said method comprising the following steps:

storing outline fonts composed of character contour data;

converting coordinates of said character contour data into vector coordinates;

generating dot data corresponding to the contours of characters from said vector coordinates and providing output accordingly;

sorting the dot data output from said generating step according to prescribed rules to generate sorted data;

generating character data as dots from said sorted data; and

storing the character data as dots corresponding to the output from said second generating step;

wherein at least two of the converting step, the first and second generating steps, and the sorting step are each performed in parallel.

6. A method as claimed in claim 5, wherein said first generating step comprises the following steps:

storing vector coordinates received from said converting step;

reading out coordinates for a starting point and an ending point, and calculating and generating straight line coordinates for a straight line connecting said starting point and said ending point;

selecting only those of said straight line coordinates that define said character contour;

selecting corner coordinates that define a corner; and

outputting said straight line coordinates and corner coordinates for use in said sorting step.

10. A method as claimed in claim 5, wherein said converting step comprises at least one of the following steps:

effecting a reduction of said character;

effecting an enlargement of said character;

effecting an inclination of said character;

effecting a rotation of said character; and

effecting a horizontal shift of said character.

7. A method of generating high-quality characters, said method comprising the following steps:

storing character contour data;

generating character contour coordinates based on said character contour data;

selecting ones of said character contour coordinates, so that an even number of the selected coordinates will be arranged in a direction of an image drawing axis;

generating further coordinates, incremented in predetermined step in the direction of the image drawing axis, from selected coordinates in odd-number positions in the direction of the image drawing axis out of the selected coordinates, until the further coordinates so generated correspond to the selected coordinates in the even-number positions; and

storing character data generated by said second generating step;

wherein the specified character is drawn in correspondence with the selected and further coordinates from the odd-number position to the even-number position as generated by the second generating step.

8. A method as claimed in claim 7, wherein said first generating step comprises:

storing said character contour data received from said storing step;

reading out coordinates for a starting point and an ending point, and calculating and generating straight line coordinates for a straight line connecting said starting point and said ending point;

selecting only those of said straight line coordinates that define said character contour;

selecting corner coordinates that define a corner; and

outputting said straight line coordinates and corner coordinates for use in said second generating step.

11. A high-quality character generating system comprising:

first memory for storing character contour data;

coordinate converting means for converting the character contour data stored in said first memory into character contour coordinates;

contour coordinate generating means for generating dot data indicative of a contour of a specified character based on the contour coordinate output from said coordinate converting means;

sorting means for sorting the dot data from said contour coordinate generating means according to prescribed rules to generate sorted data;

image drawing means for generating character data as dots from the sorted data; and

a second memory for storing the character data as dots corresponding to an output of said image drawing means,

wherein said contour coordinate generating means comprises;

an arithmetic section for calculating coordinates of the dot data;

a first selecting means for selecting dot data forming a straight line from the coordinates of dot data received from said arithmetic section;

a second selecting means for receiving the dot data from said first selecting means and for selecting dot data forming a corner and allowing other dot data to be output in order; and

control section for controlling timing of output and input data from and to said first and second selecting means.

12. A high-quality character generating system as recited in claim 11, wherein said sorting means comprises:

a plurality of Content Addressable Data Managers (CADM) for ordering said dot data in an order with smaller values placed in earlier positions;

an input interface;

an output interface;

a multiplexor connected to said plurality of CADMs, said input interface and said output interface;

control means for controlling said multiplexor to connect said input interface to a first CADM and to connect said output interface to a second CADM different from said first CADM depending upon a processing state of said control means, wherein

the input interface is connected to the contour coordinate generating means and the output interface is connected to the image drawing means and ordering operations are performed in parallel in the plurality of CADMs.

13. A high-quality character generating system comprising:

first memory for storing character contour data;

coordinate converting means for converting the character contour data stored in said first memory into contour coordinates;

contour coordinate generating means for generating dot data indicative of a contour of a specified character based on the contour coordinate output from said coordinate converting means;

sorting means for sorting the dot data from said contour coordinate generating means according to prescribed rules to generate sorted data;

image drawing means for generating character data as dots from the sorted data; and

a second memory for storing the character data as dots corresponding to an output of said image drawing means,

wherein said contour coordinate generating means comprises;

an arithmetic section for calculating coordinates of the dot data;

a first selecting means for selecting dot data forming a straight line from the coordinates of dot data received from said arithmetic section;

a second selecting means for receiving the dot data from said first selecting means and for selecting dot data forming a corner and allowing other dot data to be output in order; and

control section for controlling timing of output and input data from and to said first and second selecting means and,

wherein said sorting means comprises;

a plurality of Content Addressable Data Managers (CADM) for ordering said dot data in an order with smaller values placed in earlier positions;

an input interface;

an output interface;

a multiplexor connected to said plurality of CADMs, said input interface and said output interface;

control means for controlling said multiplexor to connect said input interface to a first CADM and to connect said output interface to a second CADM different from said first CADM depending upon a processing state of said control means, wherein

the input interface is connected to the contour coordinate generating means and the output interface is connected to the image drawing means and ordering operations are performed in parallel in the plurality of CADMs.

14. A high-quality character generating system comprising:

first memory for storing character contour data;

coordinate converting means for converting the character contour data stored in said first memory into character contour coordinates;

contour coordinate generating means for generating dot data indicative of a contour of a specified character based on the contour coordinate output from said coordinate converting means;

sorting means for sorting the dot data from said contour coordinate generating means according to prescribed rules to generate sorted data;

image drawing means for generating character data as dots from the sorted data; and

a second memory for storing the character data as dots corresponding to an output of said image drawing means,

wherein said contour coordinate generating means comprises;

an arithmetic section for calculating coordinates of the dot data;

first selecting means for selecting dot data forming a straight line in a direction not substantially parallel with a drawing direction of said drawing means;

second selecting means for selecting ones of said character contour coordinates defining a corner so that an even number of the selected coordinates will be arranged in a drawing direction and remaining coordinates will be output; and

said sorting means sorting the dot data so as to be arranged in the drawing direction in order and said drawing means draw from an odd-number dot output from said sorting means to a next even-number dot output therefrom to draw a specified character.