JPH0784739A - Data converter - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a data conversion device capable of always converting outline data into well-balanced dot data regardless of the output size. A laser printer equipped with the present data conversion device has a CPU 12 for data conversion stored in a program ROM 16 according to an output size (size when converted to dots) input from an input device 30. By executing the program, the corresponding outline data is selected from the plurality of outline data stored in the character ROM 14, and the outline data is converted into a dot pattern.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data conversion device for converting characters, figures, etc. from outline data defining the shape of their contour lines to dot data.

[0002]

2. Description of the Related Art Conventionally, when data representing characters, figures, etc. is processed using a computer and displayed in a form of printing or display, dot data is created for each pixel which is the minimum processing unit and is stored in a memory. Since an extremely large memory is required to store it in JP-B-53-410
As described in Japanese Patent Publication No. 17, gazettes, characters, figures, etc. are stored as outline data defining the shape of their contours, and converted into dot data by a device equipped with a filling means at the time of printing or display. It is desirable to display it.

Here, the filling means is capable of forming a bit map by converting the contour line into a desired size and placing bits therein.

In addition, when the resolution of the output device is low or the size of the character is small, various problems caused by a quantization error in forming a bitmap from a size-converted contour pattern are addressed. Therefore, a countermeasure process called a hint process is included. For example, line width correction for correcting the line width of characters and symbols to a beautiful balance.

[0005]

However, in the conventional method as described above, when converting outline data such as characters and figures into dot data of a small size, even if hint processing is used, an ideal outline is obtained. There is a problem in that it is impossible to represent data with a small number of dots, and as a result, it is converted into distorted dot data.

For example, in FIG. 6, 61 indicates outline data and 62 indicates dots, but such well-balanced dot data could not be obtained.

The present invention has been made to solve the above-mentioned problems, and provides a data conversion device capable of always converting outline data into well-balanced dot data regardless of the output size. Is intended.

[0008]

In order to achieve this object, the data conversion apparatus of the present invention stores a character, a figure, etc. as one or a plurality of outline data defining the shape of the contour line thereof. Means, output size designating means for designating an output size, outline selecting means for selecting the outline data stored in the storage means according to the output size designated by the output size designating means, and the outline selecting means. And a filling means for converting the selected outline data into a dot pattern.

[0009]

The data conversion apparatus of the present invention having the above-described structure, as shown in FIG. 1, has the outline selecting means according to the output size (size when converted to dots) designated by the output size designating means. Selects the corresponding outline data from the plurality of outline data stored in the storage means, and the filling means converts the outline data into a dot pattern.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the data converter of the present invention will be described below with reference to the drawings.

FIG. 2 is a diagram mainly showing a portion related to data conversion in the control circuit of the laser printer to which the present invention is applied. The microcomputer unit 10, which is the main body of this control circuit, includes a CPU 12, a character ROM 14,
A program ROM 16, a text memory 18, a working memory 20, a dot data memory 24, and a print dot data memory 26 are provided.

The CPU 12 and the like are connected by a bus 28, and an input device 30 is further connected to the bus 28.
And the printing unit 32 is connected. Here, the input device 30 sends necessary data to the microcomputer unit 10.
The printing section 32 is a section for performing printing by the laser printing method based on a command from the microcomputer section 10. The resolution of this laser printer is 300 dots / inch.

As shown in FIG. 3, the CPU 12 conceptually has an outline selecting section 37, a data reading section 36,
The hint executing unit 38, the data setting unit 40, and the like are operated. The text memory 18 stores print data composed of code data input from the input device 30, and the working memory 20 stores data necessary for executing a program.

Further, the dot data memory 24 stores the dot data set based on the filling means. Further, the print dot data memory 26 stores the dot data stored in the dot data memory 24.

The character ROM 14 stores outline data of characters such as alphabets and other characters and symbols. This outline data is composed of one or a plurality of outline data per character.

The coordinate plane that determines the outline of the character is
As shown in FIG. 4, the vertical (Y-axis) and the horizontal (X-axis) each have a size of 1000 × 1000, and uppercase letters of the alphabet are drawn between Y-axis coordinate values of 200 to 1000. , Lowercase letters are drawn using between 0 and 200. When the outline of the character is designed on such a coordinate plane, the character forming line forming the character has a width and is surrounded by the outline 46.

The outline data is created for each of a plurality of line elements forming the outline of the character, and includes the type of the line element and the coordinates of each point at both ends. The coordinates of each of these points are stored in order along a fixed direction (indicated by an arrow in the figure) defined on the contour line 46, and are stored first of the two points at both ends of each line element. The point is the start point, and the point stored later is the end point. The outline data includes straight line data and each coordinate of the start point and end point when the line element is a straight line, and includes curve data, a function formula of the curve and each coordinate of the start point, end point and auxiliary point when the line element is a circle In this case, the arc data and the coordinates of the start point, the end point, and the center of the circle are included. The character ROM 14 also stores the number N of outline data for each character.

In this laser printer, the conversion of outline data into dot data is performed on the assumption that the pixel screen 50 shown in FIG. 6 is used and the outline of the character is superimposed on the pixel screen 50. Pixel screen 50 is computational for converting outline data to dot data, but is illustrated here as being real-life for ease of understanding. or,
Here, the pixel is a minimum printing unit when printing is performed by a laser. The dot data is obtained by designating the center point of each pixel of the pixel screen existing inside the outline of the character as an on-dot.

Note that the pixels may be rectangular or any other shape. The laser printer can print characters in any size such as 4.8 points, 10 points, 12 points, 20 points, 24 points, and 30 points.
The coordinate values of the contour formed on the 0x1000 coordinate plane are converted. The coordinate values are converted on the assumption that a coordinate plane in which the length of one side of one pixel is represented by 1 is assumed to be on the pixel screen 50, and if the character of the point is represented by C × C pixels, it is 1000 By multiplying the coordinate value of each point that determines the contour on the coordinate surface of × 1000 by C / 1000, the coordinate value on the coordinate surface assumed on the pixel screen 50 can be obtained.

Further, the program ROM 16 stores various programs necessary for printing, as well as a program for converting outline data shown in the flow charts of FIGS. 8 and 9.

The conversion from outline data to dot data will be described below with reference to FIGS. 4 to 9.

First, in step S1, a character code to be converted into dot data and its conversion information are given. This conversion information is called CTM, and transformation information such as character size, rotation direction, and italics is given as a matrix.

Next, in step S2, the number of outline data is extracted based on this character code.

Then, in step S3, the number of outline data is judged, and if the outline data is one, the outline data and its hint data are fetched in step S7. In the case of two, step S4
In, the size of the character is judged from the given CTM.

If the size is smaller than the stored fixed value, the small character outline data and the small character hint data are fetched in step S5. If the size is large, the large character outline data and the large character are fetched in step S6. Import hint data for use.

Next, in step S8, hint processing is performed on the fetched outline data using the hint data similarly fetched.

The hint processing here refers to line width correction and the like, but there are many known techniques that have already been put to practical use in this technique, and the description thereof is omitted because it is not the main part of the present invention.

Then, in step S9, the outline data after the hint processing is filled with dots by using a filling means such as a raster scan method to create dot existence data (dot data).

For example, if the outline data of a large character has the contents shown in FIG. 4, dots as shown in FIG. 6 will be formed with a small number of points. In this patent, in addition to the outline shown in FIG. 7, outline data shown in FIG. 5 is stored as an outline for a small character, and in the case of a small character, by selecting it, the outline data shown in FIG. Dot data as shown can be obtained.

The dot data set as described above is stored in the dot data memory 24. The dot data memory 24 is supposed to be able to store dot data for one character when a character is printed in the largest size, and when the printing size is small, the dot data is stored in part of it. .

After setting the dot data, the dot data stored in the dot data memory 24 in step S10 is stored in the print dot data memory 26. The print dot data memory 26 is a memory that can store dot data for one page, and is stored at a predetermined position determined based on the print position of the character. Then, the printing unit prints according to the contents of the print dot memory 26.

As is apparent from the above description, in the present embodiment, the character ROM 14 constitutes a storage means for storing outline data, and the CPU 12 constitutes an outline selection means.

In the present embodiment, the outline data is formed in a part of the ROM, but it may be given from the outside by downloading or the like.

Also, in the present embodiment, one or two outline data are stored for each character.
More than one may be stored.

Further, the present invention can be applied to a laser printer for printing a graphic or a printer other than the laser printer, and of course to a device other than the printer, which needs to convert outline data such as characters and graphics into dot data. Generally, the present invention can be applied.

Besides, the present invention can be implemented in various modified and improved forms based on the knowledge of those skilled in the art.

[0037]

As is apparent from the above description, according to the data conversion apparatus of the present invention, it is possible to always convert well-balanced dot data regardless of the output size.

[Brief description of drawings]

FIG. 1 is a diagram conceptually explaining the contents of a data conversion device of the present invention.

FIG. 2 is a block diagram showing a control circuit of a laser printer equipped with the data converter of the present invention.

FIG. 3 is a diagram conceptually showing a CPU constituting the control circuit shown in FIG.

FIG. 4 is a diagram showing outline data for large characters stored in a ROM.

FIG. 5 is a diagram showing outline data for small characters stored in a ROM.

FIG. 6 is a diagram showing dot data when painting is performed based on the outline data for large characters shown in FIG.

FIG. 7 is a diagram showing dot data when painting is performed based on the outline data for small characters shown in FIG.

FIG. 8 is a flowchart for explaining a data conversion operation.

FIG. 9 is a flowchart for explaining a data conversion operation.

[Explanation of symbols]

 12 CPU 14 Character ROM 16 Program ROM 30 Input device

Claims (1)

[Claims] 1. Storage means for storing characters, figures, etc. as one or a plurality of outline data defining the shape of their contour lines, output size designating means for designating output size, and output size designating means therefor. The outline selection means for selecting the outline data stored in the storage means in accordance with the output size specified by, and the filling means for converting the outline data selected by the outline selection means into a dot pattern. Characteristic data converter.