JPH03126992A - Font controller - Google Patents

Abstract

PURPOSE:To prevent the degradation in throughput by providing a dot pattern data memory section which allows the reading and writing of the dot pattern data with which development ends and using the developed dot pattern data when this data is stored. CONSTITUTION:A font section 2 stores the font consisting of the compressed data of the dot pattern data of a prescribed typeface and a control section 3 reads out the stored and compressed data in the section 2, subjects the data to development processing, and sends the data to a purpose section 1. The dot pattern data storage section 4 stores the dot pattern data subjected to the development processing by the control section 3. The character code sent from a host device is decided and the corresponding compressed data is read out of the font section 2. The display control or printing control of the purpose section 1 is executed in accordance with the dot pattern data stored in the dot pattern data storage section 4 by the control section 3 when the corresponding compressed data is already developed. The degradation in the throughput of the font consisting of the compressed data is prevented in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a font data control device for a device that displays or prints in a dot matrix font.

(Prior Art) Generally, characters displayed or printed on a display or printer used in a computer include characters in various fonts. For example, the characters are Mincho type characters, enlarged characters, italicized characters, etc. Here, a set of characters in the same typeface is called a font. Generally, characters are displayed or printed by dots arranged in a matrix, ie, a dot matrix.

Conventionally, devices such as displays and printers that display or print using dot matrix fonts require a small number and types of fonts. Therefore, there are few problems even if the dot pattern data of each font is stored in the device as is. However, in recent years, the number and types of fonts requested by users have increased dramatically. Moreover, as fonts themselves are required to be easy to read, there are also high-quality fonts with finer dots. Such high-quality fonts require a large amount of data, which requires a storage device with a large capacity. Therefore, if it is difficult to have the dot pattern data of the required font in its original form, the dot pattern data of each character can be stored as compressed data according to a certain algorithm. Accordingly, the data is developed into dot pattern data before being displayed on a display or printer or printed.

FIG. 2 is a block diagram showing the configuration of a conventional font control device.

The illustrated device includes an object section 1, a font section 2, and a control section 3.
It consists of

The objective section 1 consists of a display section or a printing section. In the case of the display unit, it is constituted by a display such as a CRT.

In the case of the control section, it is constituted by, for example, a wire dot type printer.

Font section 2 is ROM (read only memory)
etc., and stores fonts consisting of compressed data of dot patterns of predetermined fonts.

The control section 3 reads the compressed data stored in the font section 2, decompresses it, and sends it to the destination section 1.

Next, the operation of the above-described device will be explained.

FIG. 3 is a flowchart illustrating the processing procedure of a conventional device.

First, in step S31, a process is performed to determine the character code sent from the host device, and the corresponding compressed data is read from the font unit 2. Next, in step S32, the compressed data is expanded by the control section 3 and sent to the destination section 1 as dot pattern data. Step S
At step 33, the control section 3 performs display control or printing control of the target section 1 based on this dot pattern data.

Specific methods for compressing dot pattern data include the following.

First, a dot matrix that constitutes a character is divided into multiple partial matrices. Also, each partial matrix is compared with the adjacent partial matrix for differences in dot patterns. Then, separator pits for distinguishing between different dot patterns are stored for each partial matrix. When the dot pattern of a partial matrix is the same as the dot pattern of the adjacent partial matrix, this fact is displayed on the separator pit, and the dot pattern data is deleted (see, for example, Japanese Patent Publication No. 57-27477).

During expansion processing, the separator pits are referred to for each partial matrix, and if dot pattern data is omitted, the dot pattern data of the adjacent partial matrix is copied.

(Problems to be Solved by the Invention) However, the conventional device described above has the following problems.

That is, it is necessary to expand compressed data into dot pattern data each time printing is performed, and if the same character appears many times, the exact same expansion process must be repeated. Additionally, in general, the higher the degree of compression, the more complex the compression and decompression algorithms. Therefore, there is a problem in that the expansion process takes time and the throughput of the entire device decreases.

The present invention has been made with attention to the above points, and an object of the present invention is to provide a font control device that prevents a decrease in the throughput of a font made of compressed data and improves the throughput of the entire device. It is something.

(Means for Solving the Problems) The font control device of the present invention uses a font consisting of compressed data obtained by compressing dot pattern data representing characters to be displayed or printed, and develops the compressed data of the font into dot pattern data. A dot pattern data storage unit that can read and write the dot pattern data after the expansion process is provided, and at the time of printing, whether the dot pattern data representing the desired character is stored in the dot pattern data storage unit. If the dot pattern data representing the desired character is stored, the corresponding dot pattern data is read out from the dot pattern data storage section and displayed or printed.

(Function) In the above-mentioned apparatus, when compressed data corresponding to character data is expanded into dot pattern data when printing characters, the dot pattern data that has been expanded is stored in the dot pattern data storage section. Ru.

Then, during the next printing, if dot pattern data representing a desired character is stored in the dot pattern data storage section, this dot pattern data is read out. Therefore, the process of expanding compressed data into dot pattern data can be omitted, and the throughput of the entire apparatus can be improved.

(Embodiment) FIG. 1 is a block diagram showing the configuration of a font control device of the present invention.

The illustrated device includes an object section 1, a font section 2, and a control section 3.
and a dot pattern data storage section 4.

The objective section 1 consists of a display section or a printing section, as in the conventional case. In the case of the display unit, it is constituted by a display such as a CRT. In the case of the control section, it is constituted by, for example, a wire dot type printer.

As in the past, the font unit 2 stores a font that is extracted from a ROM (read only memory) or the like and is composed of compressed data of a dot pattern of a predetermined font.

The control section 3 reads the compressed data stored in the font section 2, decompresses it, and sends it to the destination section 1. The control section 3 also controls reading and writing of the dot pattern data storage section 4.

The dot pattern data storage section 4 is comprised of a RAM (random access memory), etc., and stores dot pattern data developed by the control section 3.

Next, the operation of the above-described device will be explained.

FIG. 4 is a flowchart illustrating the processing procedure of the apparatus of the present invention.

First, in step S41, a process is performed to determine the character code sent from the host device, and the corresponding compressed data is read out from the font section 2. Next, in step S42, it is determined whether the corresponding compressed data is the expansion source. If this answer is affirmative (Yes), steps S43 to S45
Skipping this process, the process proceeds to step S46, where the control section 3 performs display control or printing control of the target section 1 based on the dot pattern data stored in the dot pattern data storage section 4.

When the answer to step S42 is negative (No), the compressed data is expanded by the control unit 3 in step S43, and dot pattern data is created. Then, in the next step S44, it is determined whether or not the expanded dot pattern data is to be stored in the storage section 4. As a method for this determination, for example, it is determined whether the storage section 4 is full or not;
There is a way to make it remember as long as it is not full.

According to this method, a certain number of dot pattern data that have appeared since the start of printing are stored.

When the determination result in step S44 is affirmative (Yes),
In the next step S45, the developed dot pattern data is stored in the dot pattern data storage section 4. On the other hand, when the determination result in step S44 is negative (No), the process proceeds to step S46 without performing such storage.

In step S46, the control section 3 performs display control or printing control on the target section 1 based on the dot pattern data read from the dot pattern data storage section 4 or the dot pattern data expanded in step 343.

As described above, by providing the dot pattern data storage section 4, the dot pattern data that has been expanded is saved, thereby reducing the number of times that the expansion process is performed.
It becomes possible to improve the throughput of the entire device.

Note that the present invention is not limited to the embodiments described above.

For example, as an example of determining whether or not to store the developed dot pattern data in step S44 in FIG. , dot pattern data of newly appearing characters may be stored.

Alternatively, the number of times each character has appeared may be stored for each character, and characters with a higher number of occurrences may be given higher priority, and a certain amount of dot pattern data of the higher priority characters may be stored. The reason why it is necessary to select the dot pattern data to be stored is that the capacity of the dot pattern data storage section 4 is limited. Since the number of types of characters actually used is often not that large compared to the number of font data, the present invention can be expected to have a very large effect.

(Effects of the Invention) As explained above, according to the font control device of the present invention, by providing a dot pattern data storage unit that can read and write dot pattern data that has been expanded, the dot pattern data storage unit can When developed dot pattern data is stored, the dot pattern data stored in the storage section is used, so that the following effects can be obtained.

That is, it is possible to minimize the reduction in throughput of the device using the compressed font data. Additionally, because it is required to maintain high throughput, fonts made of compressed data cannot be used, and even devices that used large amounts of font data can now use small-sized compressed fonts. Become.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of the font control device of the present invention, FIG. 2 is a block diagram showing the configuration of a conventional font control device, FIG. 3 is a flowchart showing the processing procedure of the conventional device, and FIG. 4 is a flowchart showing the processing procedure of the apparatus of the present invention. DESCRIPTION OF SYMBOLS 1...Object part, 2... Font part, 3... Control part, 4... Dot pattern data storage part.

Claims (1)

[Scope of Claims] A font that uses a font consisting of compressed data obtained by compressing dot pattern data representing characters to be displayed or printed, and performs a decompression process of decompressing the compressed data of the font into dot pattern data, A dot pattern data storage unit that can read and write completed dot pattern data is provided, and when printing, it is determined whether dot pattern data representing a desired character is stored in the dot pattern data storage unit, and the desired character is represented. A font control device characterized in that when dot pattern data is stored, the corresponding dot pattern data is read out from the dot pattern data storage section and displayed or printed.