JPH06183074A - Character processing device - Google Patents

Abstract

PURPOSE:To improve processing speed in a character processing device which utilizes a font cache memory. CONSTITUTION:In a font cache memory 300, diagram data such as characters are registered as dot pattern. A registration/un-registration determining means 100 determines whether an output request character is being registered in the font cache memory 300 or not. When it is being registered, a first read means 200A is started. When it is unregistered, a second read means 200B is started. The first read means 200A reads out, from the font cache memory 300, an 'identical character' which coincides with the output request character in kind of character, size of character, and typestyle. The second read means 200B reads out a 'similar character' with which only kind of character and size of character coincide.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a character processing device, and more particularly, to a character cache device for expanding graphic data (vector font) of characters or the like expressed in vector format into dot format data and registering the data. It relates to a character processing device.

[0002]

2. Description of the Related Art Using character data represented in a vector format has an advantage that high quality characters can be obtained, but on the other hand, there is a problem that it takes time to develop the character data in dot format.

In order to solve this problem, once expanded dot format character data is registered in the font cache memory, and when the same character is requested later, the data in the font cache memory is reused and high speed is achieved. A technique of outputting a document to a computer has been developed. For example, the IPSJ journal Vol. 31, No. 1, it is discussed as "high-quality Japanese character high-speed output method".

Since the storage area of the font cache memory is limited, it is necessary to replace the dot data by expelling the unused dot data and storing new dot data.

Conventionally, methods such as the FIFO method and the LRU method have been generally used to determine which dot data is not required.

The FIFO (First in First Out) type font cache is a system in which the oldest one stored in the font cache memory is flushed first.

[0007] On the other hand, the LRU (Least Recentry Used) font cache is a method in which, of the fonts stored in the font cache memory, the one with the oldest used time is expelled first.

[0008]

In the character processing device having the font cache memory described above, high-quality characters can always be obtained, but since the characters that appear for the first time must be expanded from the vector font, the expansion time is increased. Is required.

On the other hand, there are cases where it is desired to give priority to the processing speed over the quality of characters, such as when laying out a document or when an output document is not an official document. In such a case, the character requested to be output and the character actually output are
For the time being, if the character types (character codes) match,
There is no particular problem even if the typefaces (Mincho, Gothic, etc.) do not match.

However, in the above-mentioned conventional technique, if none of the character type, character size, and typeface matches the output request character, the character cannot be read from the font cache memory, which makes high-speed processing difficult. .

An object of the present invention is to solve the above-mentioned problems of the prior art and to further improve the processing speed of a character processing device using a font cache memory.

[0012]

In order to achieve the above object, according to the present invention, in a character processing device having a font cache memory for expanding and registering a vector font in dot format data, an output request character Registered / unregistered determining means for determining whether or not the same character is already registered in the font cache memory; and, if already registered, first reading means for reading the same character from the font cache memory, and unregistered. Then, the second read means for reading a character similar to the output request character from the font cache memory is provided.

[0013]

According to the above configuration, even if a character that completely matches the output request character is not registered in the font cache memory, a character similar to this is read instead by the second reading means, so that the similar character is obtained. If the characters are registered, the expansion processing is unnecessary and the processing speed is improved.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram for explaining the function of the first embodiment of the present invention.

In the font cache memory 300, a large number of graphic data such as characters developed from vector fonts are registered as dot patterns. The registered / unregistered determining unit 100 determines whether the output request character is already registered or unregistered in the font cache memory 300, and if it is already registered, the first reading unit 200A is activated,
If it is not registered, the second reading means 200B is activated.

The first reading means 200A reads the "same character" whose character type (character code), character size, and typeface all match the output request character from the font cache memory 300 and outputs it.

The second reading means 200B reads "similar characters" whose character type and character size are the same as those of the output request character and differs only in the typeface from the font cache memory 300 and outputs them.

According to the above configuration, even if a character that exactly matches the output request character is not registered in the font cache memory 300, a character similar to this is read by the second reading means 200B instead. If similar characters are registered, the expansion process becomes unnecessary and the processing speed can be improved.

FIG. 4 is a block diagram showing the hardware arrangement of a character processing apparatus (printer apparatus) according to an embodiment of the present invention.

In the figure, the ROM 2 stores a program for controlling the overall operation of the character processing device, a program for controlling the font cache memory 8, a program for defining the operation of the printer immediately after the power is turned on, and an output request character. The font cache memory 8 stores a program for determining whether or not the font cache memory 8 is already registered. RA
M3 is used as a save area for the stack of the CPU 1.

The CPU 1 sends commands and image data to the printer engine 5 through the printer interface 4, and conversely, the printer engine 5 sends the internal state of the printer engine 5 to the CPU 1 through the printer interface 4. . The printer engine 5 actually prints the image data transmitted through the printer interface 4 on paper.

The CPU 1 has a host interface 7
Via the host workstation 6 to receive document data to be printed, print control commands, etc., and based on them, the vector format data stored in the vector font memory 9 is expanded into dot format data. The operation of forming a bitmap image for one page in the page memory 10 and sending it to the printer engine 5 is controlled.

Next, an example of the structure of the document data received by the CPU 1 from the host workstation 6 will be described with reference to FIG.

The structure of one page of document data is made up of a position designation command, a command for each character of the document, a page print command, and the like. The position command command is a command for instructing the print position of the first character of the document. The commands for each of the characters include a font setting command, a character printing command, and the like. The page print command is provided at the end of each page of document data. It should be noted that FIG. 3 shows only the instructions related to the operation of the present invention, and the description of other instructions is omitted.

Next, the operation of this embodiment will be described in detail with reference to the flowcharts shown in FIGS. 5 and 6 and the document data shown in FIG.

In step S1 of FIG. 5, the CPU1
First receives document data from the host computer 1. The document data is stored in the RAM 3.

In step S2, the operator sets the operation mode. In the present embodiment, if the character type and size match, the standard mode for reading from the font cache memory 8 only the characters whose character type, character size, and typeface all match the output request character, and the font type mismatch is ignored. There is a preview mode to use.

When the setting of the operation mode is completed, the process proceeds to step S3, and the CPU 1 executes the process of developing the document data into a bit map image. An example of the expansion processing will be described with reference to the flowchart in FIG.

When the expansion process starts, step S in FIG.
One instruction is read in 302 and a position designation instruction is input at first, so the determination in step S303 is negative, and in step S305, it is determined whether or not it is a font setting instruction.

If this judgment is negative, step S30
At 7, it is determined whether the command is a character print command. In the present embodiment, this determination is also negative, the process proceeds to step S309 to execute the process in response to the command, and then returns to step S302 to input the next one command.

As is apparent from FIG. 3, since the font setting command (12-po, Mincho type) is input this time, the determination at step S303 becomes negative and step S305.
Go to. This time, the determination in step S305 is affirmative, so the flow advances to step S306 to update the current font. That is, in this example, the current font (character size and typeface) is set to "12-po, Mincho-type."

When the process of step S306 is completed, the process returns to step S302 again, and the next one command is input. In this example, a character print command (A) is input. Therefore, the determinations of steps S303 and S305 following step S302 are negative, and the determination of step S307 is affirmative, and the process proceeds to step S308.

In step S308, the font cache memory (FCM) 8 is searched by using the character code and the font and character size of the current font as keys.
In step S310, it is determined whether or not the dot data relating to the character is registered in the font cache memory 8. If registered, step S31
At 8, the dot data is output from the font cache memory 8 to the page memory 10.

On the other hand, if not registered, step S3.
In 11, the current operation mode is determined, and if the standard mode is set, then in step S315, it is determined whether registration in the font cache memory 8 is possible. If registration is not possible, in step S316, the dot data registered in the font cache memory 8 by the LRU method is selectively deleted, and registration becomes possible.
In step S317, the vector font corresponding to the character is expanded into dot data and registered in the font cache memory 8. In step S318, the dot data is output from the font cache memory 8 to the page memory 10.

On the other hand, if it is determined in step S311 that the preview mode is set, step S312 is executed.
At S319, a process of outputting a character similar to the character is executed.

In step S312, the font cache memory 8 is searched using only the character code and the character size as keys. If it is determined in step S313 that the font cache memory 8 is not registered, the process jumps to step S315.
Further, if it is determined that it is registered, step S31
In 9, the dot data of the retrieved similar character is output from the font cache memory 8 to the page memory 10.

Thereafter, when the page print command is read, step S303 becomes affirmative and the process proceeds to step S4 of the main routine. In steps S4 and S5, the CPU
1 sends a bitmap image for one page from the page memory 10 to the printer engine 5 via the printer interface 4, and printing on the recording paper is executed.

According to the present embodiment, when the document is laid out, the output document is not an official document, etc.
In preview mode, which requires high-speed processing even if the character quality is slightly inferior, if the requested character is not registered in the font cache memory, "similar character", which has a different typeface and character code and size, is used instead. Since this is done, the expansion time is unnecessary and high-speed processing becomes possible.

By the way, in the above-described first embodiment, it is explained that the similar character is retrieved from the font cache memory 8 by using the character code and the character size as keys in the preview mode. In the second embodiment, similar characters are searched using only the character code as a key.

FIG. 2 is a block diagram for explaining the function of the second embodiment of the present invention, in which the same symbols as those used above represent the same or equivalent portions.

In the figure, third reading means 200C
Is the same as the output request character, and at least "similar characters" having different sizes are set in the font cache memory 30.
Read from 0 and output. The approximating means 400 enlarges or reduces the read similar character in accordance with the output request character, and makes the size of the similar character approximately equal to the size of the output request character to approximate both.

FIG. 7 is a flow chart for explaining the expansion processing according to the second embodiment of the present invention. In the steps denoted by the same reference numerals as the processing described with reference to FIG. 6, the same or equivalent processing is executed. Therefore, the description thereof will be omitted.

If it is determined in step S311 that the preview mode is set, step S31
In 2a, the font cache memory 8 is searched using the character code as a key. When it is determined in step S313 that a character having the same character code is registered, in step S314, the character is enlarged or reduced according to the requested character size.

According to this embodiment, under the preview mode in which high-speed processing is desired even if the character quality is slightly inferior, if the requested character is not registered in the font cache memory, the character code is different from the character size but the character code is different. Since the matching character is read and it is enlarged or reduced according to the size of the output request character, even if the character code matches but only the characters of different sizes are registered,
High-speed processing is possible because the expansion time is unnecessary.

[0045]

As described above, according to the present invention, the following effects can be achieved. (1) If you want to perform high-speed processing even if the character quality is somewhat inferior, such as when laying out a document, even if the requested character is not registered in the font cache memory, the character and character code and size match. Since "similar characters" are read out and used as a substitute, the expansion time is unnecessary and high-speed processing is possible. (2) If you want high-speed processing even if the character quality is slightly inferior, even if the requested character is not registered in the font cache memory, read out "similar character" whose character code matches the character code and request it. Since the characters are enlarged or reduced according to the size of the character to be used instead, even when only characters having the same character code but different sizes are registered, the expansion time becomes unnecessary and high-speed processing becomes possible.

[Brief description of drawings]

FIG. 1 is a functional block diagram of a first embodiment of the present invention.

FIG. 2 is a functional block diagram of a second embodiment of the present invention.

FIG. 3 is a diagram showing an outline of document data.

FIG. 4 is a block diagram of a document processing apparatus according to an embodiment of the present invention.

FIG. 5 is a flowchart showing the operation of the first exemplary embodiment of the present invention.

FIG. 6 is a flowchart showing details of step S3 in FIG.

FIG. 7 is a flowchart showing the operation of the second exemplary embodiment of the present invention.

[Explanation of symbols]

1 ... CPU, 2 ... ROM, 3 ... RAM, 4 ... Printer I
/ F, 5 ... Printer engine, 6 ... Host W / S, 7 ...
Host I / F, 8, 500 ... Font cache memory, 9 ... Vector font memory, 10 ... Page memory, 100 ... Registered / unregistered determination means, 200A ... First
Reading means, 200B ... second reading means, 200C ... third reading means, 300 ... font cache memory, 4
00 ... approximating means

Claims (3)

[Claims] 1. A font cache memory for expanding and registering a vector font in dot format data,
In a character processing device that reads registered data from the font cache memory without expanding it again, a registered / unregistered determining unit that determines whether or not the same character as the output request character is already registered in the font cache memory; If the character string is registered, the same character is read from the font cache memory, and if the character string is not registered, the character similar to the output request character is read from the font cache memory. A character processing device characterized by the above. 2. The character processing apparatus according to claim 1, further comprising an approximation unit that approximates the read similar character to an output request character. 3. The character processing device according to claim 2, wherein the approximating means enlarges or reduces the similar character in accordance with the size of the output request character.