JPH08234720A - Data structure of font data memory - Google Patents

Abstract

PURPOSE: To make it possible to decrease the memory capacity of font data memories by storing font data canon to plural type faces only in the specific type face and storing at least the type face instruction information to instruct the specific type face in place of the font data for the other type faces. CONSTITUTION: The outline data regulating contour lines for each of the plural characters, such as Alphabet characters and symbols for each of the three type faces 'type face A', 'type face B', 'type face C' of a MINCHO system are stored in correspondence to character codes in a font data memory 23. The font index information consisting of font names and storage regions of font information are stored in each of the three type faces A, B, C in a type face management memory 23a. The font data common to the three type faces are stored into the memory 23b of the specific type face A and the type face instruction data instructing the type face A is stored in place of the font data in the memories 23c, 23d for the other type faces A, B, C.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data structure of a font data memory in which font information for a plurality of fonts is stored. In particular, the font data common to a plurality of fonts is shared to reduce the storage capacity and the shared fonts. The present invention relates to a device in which a data storage position is instructed by typeface instruction information or code instruction information.

[0002]

2. Description of the Related Art Conventionally, in general, a large computer or personal computer is connected to various printing devices such as a laser printer, and printing data such as characters or graphics is transmitted from these computers to the printing device to print characters or graphics. A printing system has been put into practical use, which is capable of printing such items on a printing medium at high speed. Here, the transmitted print data can be printed in a desired typeface selected from a plurality of typefaces.
The printing device is equipped with a dot pattern data creation device, and the font data memory of the dot pattern data creation device contains font data such as outline font data and dot pattern data for multiple Mincho typefaces and Gothic typefaces for each typeface. I try to remember them separately. On the computer side, the typeface instruction code is transmitted prior to the print data of the character string used for printing.

That is, the font data memory provided in this dot pattern data creating apparatus is composed of a non-volatile memory such as a ROM or a hard disk. In this font data memory, font information of a plurality of characters or symbols is stored in each font data. It is composed of outline font data representing characters or shapes, font data such as dot pattern data, and index information including the code of the character or symbol corresponding to each font data and the font data storage position. Minutes are stored. Here, for example, symbols such as “+”, “−”, “$”, ... Are often common font data in a plurality of Mincho typefaces, and in a plurality of Gothic typefaces. It is often common font data.

Therefore, as for these common font data, the font data of a specific typeface among a plurality of Mincho typefaces or Gothic typeface types is stored, while the font data of a typeface other than the specific typeface is stored. Only the start address of the font data stored in a specific typeface is stored so that the memory capacity of the font data memory is reduced. Then, when the print data is received, when the font data corresponding to the character code of the typeface designated by the typeface designation data is read out based on the index information and the leading address is stored instead of the font data, Common font data can be read from a specific typeface based on the start address.

On the other hand, in Japanese Patent Laid-Open No. 4-217019, the character groups to be printed are the first group "the character group different for each typeface" which is most frequently used and the second group "Limited sensitivity". Character groups ”and“ general-purpose character group ”, which is the third group with the least frequency of use, are stored in separate font data memories, so that they can be shared by multiple typefaces (typefaces). , For example, "+", "-", "$", ...
A general-purpose symbol such as "can be stored in common as a" general-purpose character group ", and a printer in which the memory capacity of the font data memory is reduced is described.

[0006]

As described above, in the font data memory, the font data common to a plurality of fonts stores the font data of a specific font, while the font data of a font other than the specific font is stored. When only the start address of the font data stored in the particular typeface is stored as the font data, the font data memory is generally a non-volatile memory, and the address of this non-volatile memory in the control system is the printer model. Since it is often different for each model, the start address to be stored as font data of a typeface other than the specific typeface is set individually for each model, and the work of storing this start address is complicated. Each time you change the storage area of a specific typeface, you have to store the complicated start address. There is a problem that becomes.

On the other hand, in the printer described in Japanese Patent Laid-Open No. 4-217019, characters and symbols that can be shared are:
There are multiple types, and when sharing all sharable font data, it is necessary to separate the character groups each time the combination of typefaces to be stored is changed. There is the problem of complication. Furthermore, even if the font data can be shared by multiple typefaces, if the code data is different,
There is a problem that the code data cannot be changed and the sharable font data is stored in a duplicated manner, and the data amount of the font data cannot be reduced.

An object of the present invention is to make it possible to surely share common font data among a plurality of fonts to reduce the memory capacity of the font data memory, and to change the storage area of a specific font storing the common font data. Even so, it is to provide a data structure of a font data memory that can simplify font data management.

[0009]

According to the data structure of a font data memory of claim 1, font information of a plurality of characters and symbols is font data representing the shape of each character and symbol,
In the data structure of the font data memory, which is composed of the code of the character or symbol corresponding to each font data and the index information including the font data storage position, and the font information is stored in multiple fonts, For font data that is common to multiple fonts, the font data for the specific font of the multiple fonts is stored, while at least the font instruction information that indicates the specific font is used as the font data for the other fonts. It is stored.

Here, in the data structure of the font data memory of claim 2, in the invention of claim 1, as the font data of the other typeface, in addition to the typeface instruction information for instructing a specific typeface, a specific typeface is added. It stores code instruction information for instructing codes of characters and symbols in.

[0011]

In the data structure of the font data memory according to the first aspect, the font information of a plurality of characters and symbols is the font data representing the shape of each character and symbol and the code of the character and symbol corresponding to each font data. The font data is stored in a font data memory, and the font information is stored in the font data memory for a plurality of fonts. Regarding font data common to a plurality of fonts among font data of a plurality of characters and symbols, the font data of a particular font of the plurality of fonts is stored, while at least a specific font data of other fonts is stored. Stores typeface instruction information for instructing a typeface.

As described above, since font data common to a plurality of fonts is stored only in a specific font, and font information for other fonts is stored instead of the font data. It is possible to reduce the font information for a plurality of fonts, thereby reducing the memory capacity of the font data memory. Furthermore,
Even if the storage area of the specific typeface is changed, the font data management can be simplified by the typeface instruction information for instructing the specific typeface.

In the data structure of the font data memory of claim 2, the same operation as in claim 1 is achieved, but as font data of the other typeface, in addition to the typeface instruction information for instructing a specific typeface, a specific type is specified. Since the code instruction information for instructing the codes of the characters and symbols in the typeface is stored, even if the font data can be shared and the code data are different, the different code data is stored as the code instruction information. By doing so, duplicate storage of font data can be avoided, and the amount of data in the font data memory can be reliably reduced.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, print data such as text data is received from an external device, and with respect to the text data, dot pattern data is created by converting outline data (font data) representing a character outline into dot data for each pixel for printing. The present invention is applied to the font data memory of the dot pattern data creation device provided in the laser printer. First, the laser printer LP will be briefly described. Basically, as shown in FIG.
0, a dot pattern data creating device 20, and a printing mechanism 40.

The control unit 10 of the laser printer LP is provided with a serial interface for receiving various data supplied from the external device 50, a video controller, a DC controller, etc. The dot pattern data is provided to the printing mechanism 40 by a laser diode, which is a light emitting element of a semiconductor laser, a polyhedral mirror,
This is for driving and controlling a developing mechanism, a fixing mechanism and the like to print on a printing paper. The control unit 10 is the same as the one that is generally used and is not directly related to the present invention, so a detailed description thereof will be omitted.

The dot pattern data creating device 20
2, is basically composed of a CPU 21, ROMs 23 to 24 connected to the CPU 21 via a bus 25 such as a data bus, and a RAM 30, and the bus 25 is a control unit. It is connected to the bus in 10. In the font data memory 23 composed of the ROM, for each of the three Mincho typefaces “typeface A”, “typeface B”, and “typeface C”, for each of a plurality of characters such as alphabet letters, numbers and symbols,
Outline data defining a contour line is stored in association with a character code. Here, the font index management memory 23a stores font index information including a font name and a font information storage area for each of the three fonts "Font A", "Font B", and "Font C".

That is, in the font information memory 23b in which "type A" (this corresponds to a specific type) is stored,
As shown in FIG. 3, a font name “Font A” and font information composed of index information and font data are stored. As index information, in addition to uppercase alphabetic characters "A, B, C, ... Z", lowercase alphabetic characters "a, b, c, ... Z", numbers "1 to 0", "+" , "-", "/", ...
Corresponds to code data of multiple characters consisting of symbols such as, and offset data (corresponding to the font data storage position) that indicates the address of the font data area where the font data of these characters, numbers, and symbols are stored. In addition, they are stored in a predetermined order. Further, outline data of the plurality of characters is stored as font data in a predetermined order.

Further, as shown in FIG. 4, the font information memory 23c in which "typeface B" is stored stores the typeface name "typeface B" and font information composed of index information and font data. Has been done. As the index information, as in the case of the "type A", the code data of a plurality of characters and the offset data indicating the address of the font data area in which the font data of these characters, numbers, and symbols are stored are associated with each other. And are stored in a predetermined order. Furthermore, outline data of these multiple characters is used as font data.
It is stored in a predetermined order. However, "+", "-", "/", ... Common to the font data of "Type A"
・ For font data of symbols such as "Type A"
Typeface instruction data for instructing (corresponding to typeface instruction information)
Are stored respectively.

Further, as shown in FIG. 5, the font information memory 23d in which "typeface C" is stored stores the typeface name "typeface C" and font information composed of index information and font data. Has been done. As the index information, as in the case of the "type A", the code data of a plurality of characters and the offset data indicating the address of the font data area in which the font data of these characters, numbers, and symbols are stored are associated with each other. And are stored in a predetermined order.

Further, as font data, outline data of the plurality of characters is stored in a predetermined order. However, regarding the font data of symbols such as "+", "-", "/", etc. which are common to the font data of "Type A", the type designation data designating "Type A" are stored respectively. Has been done. In particular, for the symbol "/", since the code data is different from the "/" of the "type A", the code instruction data (corresponding to the code instruction information) for instructing the code in the "type A" is stored. . Here, these "type B" and "type C" correspond to other typefaces.

The program memory 24, which is a ROM, stores various control programs for controlling the driving of the laser printer LP, including the dot pattern data creation control described later. The received data memory 31 of the RAM 30 stores a character code of a character received from the external device 50, size data designating a print size, and the like. The outline data memory 32 stores the outline data read out for each character. The created print dot pattern data is expanded and stored in the print data buffer 33.

Next, the dot pattern data creating device 20
The routine of the dot pattern data creation control performed in step 2 will be described with reference to the flowchart of FIG.
In addition, reference numeral Si (i = 10, 11, 12, ...) In the drawing represents each step. However, in this control, it is assumed that the external device 50 transmits a typeface instruction code for instructing a typeface and print data including a character string of characters or symbols. The print data is transmitted from the external device 50,
This control is started when the data is stored in the reception data memory 31, and first, the typeface instruction data is received from the reception data memory 31.
The character code of the character or symbol is read (S1
0), the font index information in the font management memory 23a is searched for the font name designated by the font designating data (S11).

When the designated typeface is stored in the font data memory 23 (S12: Yes).
), The index information of the designated typeface is searched for the read character code, and when the character code is stored (S13: Yes
), Font data is searched based on the offset data of the character code, and when the font data is stored (S14: Yes), the font data is read and stored in the outline data memory 32 (S19). . Next, the outline data memory 32
The dot pattern data is created based on the outline data of, and the dot pattern data is expanded as print dot pattern data in the print data buffer 33 (S20), the control is terminated, and the process returns to the main routine to print. The mechanism 40 prints on the printing paper.

By the way, when the font data of the read character code is searched, when the font data is not stored (S14: No), and the font designating data is stored instead of the font data,
The typeface instruction data is read (S15: Yes), and is replaced with the read typeface instruction data instead of the transmitted typeface instruction data (S16). Next, when the code instruction data is not stored in addition to the typeface instruction data (S17: No), the process returns to S11 without changing the character code. Then, after S11 is executed and the font data of the changed font is stored (S12 to S14: Yes), the created dot pattern data for printing is expanded in the print data buffer 33 by S19 to S20. To be done.

For example, when the transmitted typeface instruction data is "typeface A" and the read character is the symbol "+", the font data of the symbol "+" is stored as shown in FIG. The font data is read out and processed into dot pattern data. However, when the transmitted typeface instruction data is “typeface B” or “typeface C” and the read character is the symbol “+”, as shown in FIGS. 4 and 5, instead of font data, “typeface A” is used. The font data of the symbol "+" is read from the "font A" because the font designating data for indicating "" is stored.

By the way, when the font designating data and the code designating data are stored in place of the read character code font data (S17: Yes), the code designating data is designated instead of the read character code. Is changed to a character code (S18),
Return to S11. Then, after S11 is executed and the character code in the changed typeface is stored (S12 to S14: Yes), by S19 to S20,
The created print dot pattern data is expanded in the print data buffer 33. For example, when the transmitted typeface instruction data is “typeface C” and the read character is the symbol “/”, as shown in FIG. 5, the typeface instruction data indicating “typeface A” is used instead of the font data. ,
Since the character code in the "type A" is stored, the font data of the symbol "/" is "type A".
It is read as the character code of.

As described above, the font information composed of the font data and the index information is "type A",
When three typefaces consisting of "typeface B" and "typeface C" are stored, the common symbols "+", "-",
The font data such as “/”, ... Is stored only in the specific font A, and the font data for the other fonts B and C is replaced with the font instruction information or the code instruction data for instructing the specific font. Since it is stored, font data can be shared, and even if the code data is different, by storing the different code data as code instruction data, duplicate storage of font data can be avoided. It is possible to reduce the font information for three typefaces, and thus it is possible to surely reduce the memory capacity of the font data memory 23. Further, by the typeface instruction data for instructing the specific typeface A, the specific typeface A
Even if the storage area of the control system is changed, the font data management can be simplified.

The three typefaces, "typeface A", "typeface B", and "typeface C" are managed by font numbers, and typeface instruction data and code instruction data are included in the index information of the font management memory 23a. For example, within the scope of the technical idea of the present invention, various modifications may be made based on existing technology or technology obvious to those skilled in the art. It is needless to say that the present invention can be applied to the data structure of various font data memories that store outline font data and dot pattern data of a plurality of fonts.

[0029]

According to the data structure of the font data memory of claim 1, when the font information composed of the font data and the index information is stored for a plurality of fonts, the font data common to the plurality of fonts is specified. Since it stores only in the typefaces of other, and at least the typeface instruction information for instructing a specific typeface is stored instead of the font data for the other typefaces, the font information for a plurality of typefaces can be reduced, As a result, the memory capacity of the font data memory can be reduced. Further, the font data management can be simplified even if the storage area of the specific font is changed by the font designating information for designating the specific font.

According to the data structure of the font data memory of claim 2, the same effect as that of claim 1 can be obtained, but as font data of the other typeface, in addition to the typeface instruction information for instructing a specific typeface, Since the code instruction information for instructing the character code in a specific typeface is stored, it is possible to share font data, and even if the code data is different, store the different code data as code instruction information. Thus, it is possible to avoid duplicate storage of font data, and it is possible to reliably reduce the amount of data in the font data memory.

[Brief description of drawings]

FIG. 1 is a schematic block diagram of a control system of a laser printer.

FIG. 2 is a block diagram of a control system of a dot pattern data creation device of a laser printer.

3 is a diagram showing a data structure of a typeface A. FIG.

FIG. 4 is a diagram showing a data structure of a typeface B.

5 is a diagram showing a data structure of a typeface C. FIG.

FIG. 6 is a schematic flowchart of a dot pattern data creation control routine.

[Explanation of symbols]

 LP laser printer 20 dot pattern data generator 23 font data memory (ROM)

Claims (2)

[Claims] 1. The font information of a plurality of characters or symbols is composed of font data representing the shape of each character or symbol and index information including a code of the character or symbol corresponding to each font data and a font data storage position. In the data structure of the font data memory configured to store the font information for a plurality of typefaces, the font data common to a plurality of typefaces among the font data of the plurality of characters and symbols is a specific typeface among the plurality of typefaces. While storing at least font data of other fonts, at least font designating information designating the particular font is stored as font data of other fonts. 2. As the font data of the other typeface,
The data structure of the font data memory according to claim 1, wherein, in addition to the typeface instruction information for instructing the specific typeface, code instruction information for instructing a code of a character or a symbol in the specific typeface is stored.