JPH0341496A - Font generating device with gradation - Google Patents

Abstract

PURPOSE:To reduce the capacity of gradation font data by providing a font storage means stored with font data as a bit map and a gradation difference font data storage means stored with difference data for gradation representation and position information on the bit map. CONSTITUTION:A binary font memory 1 stores binary font data as bit map data. A gradation difference font data memory 2 stores the difference data for gradation representation and the position information on the bit map. A control arithmetic circuit 4 calculates the difference data in the memory 2 for the binary font data on the memory 1 according to the gradation data in a gradation data table 3 to generate gradation data. At this time, the difference data on the memory 2 is stored together with the position information on the bit map, so only data on dots having differences are required.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a font generation device, and more particularly to a font generation device equipped with font data storage means having gradations.

(Prior Art) In recent years, many printers and displays that can express gradation by inputting digital signals have become common. However, font data for outputting and displaying characters, symbols, etc. is often expressed in binary format as in the past, and font data with gradation is not widely used.

The reason for this is that it is considered that characters are normally expressed in a single color, and that even binary data requires a large amount of font data (approximately 7,000 Japanese standard characters alone). If you want to express gradation, the data capacity will be several times that amount,
This has a significant impact on the cost of the product. However, when characters, etc. are expressed using binary data, not only are the fonts monotonous with no gradation, but the jagged edges of the diagonal lines become noticeable, making it impossible to obtain beautiful fonts.

As a solution to this problem, if the diagonal lines are expressed using gradation, the jaggedness of the diagonal lines becomes less noticeable, and the demand for gradation font data is also increasing in terms of obtaining beautiful fonts.

For example, the image processing device described in Japanese Patent Application Laid-Open No. 62-208176 creates a plurality of patterns corresponding to gradations of a predetermined size in a character font ROM that stores font patterns such as characters or symbols. Using a storage means for storing data, select a desired gradation pattern from a plurality of patterns stored in the storage means, and masking the selected pattern with data from the character font ROM to change the gradation. It is possible to generate a pattern with

Therefore, since many types of patterns can be obtained by combining gradation patterns, even if the memory capacity is smaller than when preparing multiple types of bright and dark character fonts, multiple gradation patterns can be obtained. This requires a considerable amount of memory capacity.

(Problems to be Solved by the Invention) The present invention has been made for the purpose of reducing the capacity of font data in a font generating device having gradations.

(Means for Solving the Problems) The present invention provides a font generating device having gradation, in which two
The present invention includes a binary font storage means for storing value font data as bitmap data, and a gradation difference font data storage means for storing difference data for gradation expression and its position information on the bitmap. This is a characteristic feature.

Instead of providing an index area in the gradation difference font data storage means, index index storage means for storing addresses in the gradation difference font data storage means for character codes may be interposed.

(Function) The function of the present invention is to perform the following on binary font data from the binary font storage means for storing bitmap data.
The gradation data is created by calculating the difference data for gradation expression from the gradation difference font data storage means. Since the difference data for expressing the gradation in the gradation difference font data storage means is stored together with the position information on the bitmap, data of only the dots having the difference is sufficient.

(Example) FIG. 1 is a schematic diagram for explaining an example of the present invention. In the figure, 1 is a binary font memory that stores binary font data as bit mat map data, 2 is a gradation difference font data memory that stores difference data for expressing gradation and its position on the bitmap, and 3 is a gradation difference font data memory that stores difference data for expressing gradation and its position on the bitmap. A gradation data table 4 stores the address from which a certain character data starts in the gradation difference font data memory 2, and 4 reads out the data in the binary font memory 1 and the data in the gradation difference font data memory 2, respectively. A control calculation circuit that performs calculations according to values and writes out the results; 5
is a gradation font buffer that temporarily stores gradation font data from the control arithmetic circuit.

The embodiment of the invention shown in FIG. 1 will be described with reference to FIGS. 2 to 5. The bitmap is 40 x 40 (bit) font data as shown in Figure 4, the gray scale is 256 gradations (8 bits), and the character is the kanji ``small''. explain. Of course, the number of dots and the number of gradations in the bitmap are not limited to these values, and any appropriate values can be adopted.

The binary font memory 1 stores binary bitmap data for each character as shown in FIG. The data format is well-known, and one line is from 0 to 39 in the X direction of the point address, and the lines are scanned from ○ to 39 in the Y direction, and for a total of 40 x 40 = 1600 addresses, "0 ” or “1” is written. Therefore, the hatched area in Figure 4 is marked "1", and the other white areas are marked "O".
” is written.

In the gradation font data memory 2, as shown in FIG. Address data indicating the position of the dot on the bitmap is used as point address (X) and point address (Y) as data.
It is stored for each character. In this case, the point address (X) and point address (Y) are each stored as 8-bit binary data. therefore,
Data up to 256x256 can be handled as a point address. The gradation difference data is similarly 8-bit binary data and can handle 256 gradations. “○” and “1” in the binary font memory 1 described above
” is data corresponding to gradations O and 255, so if the difference between them is ◯, the gradation difference data is omitted and is not stored in the gradation difference font data memory.

As shown in Fig. 3, the gradation data table 3 contains each character code and the position of the data in the gradation difference font data memory 2 (where the data of that character starts).
is stored as a gradation font data memory address. The character code is expressed in hexadecimal code, and the gradation font data memory address stores the start address, which is the starting position in memory of the gradation difference font data for each character shown in Figure 2, in hexadecimal code. ing.

In this embodiment, the memory for the gradation difference font data does not store the character code together with the character code, so it does not have an index, and by interposing the gradation data table explained in FIG. 3, the gradation for the accessed character is Added key difference font data. This method reduces the overall memory capacity, but if a character code area is provided in the gradation difference font data memory, a gradation data table is not necessary. Therefore, in FIG. 4, a value corresponding to the gradation difference is written only in the hatched area in FIG. 5.

When the control arithmetic circuit 4 is given a character code, it sequentially reads data corresponding to that character from the binary font memory 1, for example, every 16 bits.

Furthermore, manually enter the character code in the gradation data table 3,
The start address of the difference data corresponding to the character on the gradation difference font data memory 2 is obtained. Then, the start address is manually entered into the gradation difference font data memory 2, and the position data on the bitmap regarding that data and the difference data at that position are sequentially read out.

The positions on the bitmap that are not stored in the gradation difference font data memory 2 are stored in the binary font memory 1.
Refer only to the value read from , and if it is "○",
If it is "1", 255 is written to the corresponding bitmap position of the gradation font buffer 5. Furthermore, regarding the position on the bitmap stored in the gradation difference font data memory 2, the following calculation is performed using the values in the binary font memory and the gradation difference font data memory 2, and the results are converted into gradations. Write to the corresponding bitmap position in font buffer 5.

(2) When the value of the binary font memory is "O" The value of the gradation difference font data memory is used as the calculation result.

(2) When the value of the binary font memory is "1", the value of the 255-gradation difference font data memory is used as the calculation result.

In addition, to indicate the end of the Q-character data in the gradation difference font data memory 2, even if the difference data is O at the final bit position, it is always stored as (39, 39, difference data). It is possible to judge by setting the

In this way, a grayscale font can be obtained by storing one character's worth of gradation font data in the gradation font buffer 5 and then sending it to the output device.

(Effects of the Invention) As is clear from the above description, according to the present invention, the capacity of gradation font data can be significantly reduced compared to the conventional one.

For example, in the above embodiment (taking the character "small" as an example), assume that the address is represented by 8 bits + 8 bits.

) and binary data in conventional font memory, 25
Comparing the amount of data with 6-level gradation data (referred to as the conventional method), in the above example, [40 (bits) x 40 (bits) + 27 (voices) x 24 (address 16, gradation 8 bits)]: 8 bits = 281 BYTE + table memory amount / number of characters (number) In the conventional method, [40 (bits) is decreasing.

Furthermore, looking at all the characters on average, for example, the amount of data in the case of a gray scale of 256 x 256 bits x 8 gradations is that there are 100 points of bits with gradations (points that become gray scale). Assuming this, in the present invention, [256x256+100x24] ÷ 8 + number BTE = 8492 + number BYTE, whereas in the conventional method, it becomes [256x256x8 ÷ 8] 11 = 65536 BYTE. It can be seen that according to the invention, the memory capacity can be significantly reduced.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a schematic diagram of an embodiment of the present invention, FIG. 2 is an explanatory diagram of an example of data contents of a gradation font data memory, and FIG. 3 is a gradation difference font FIG. 4 is an explanatory diagram of an example of the data contents of the buffer, FIG. 4 is an explanatory diagram of an image of a bitmap font, and FIG. 5 is an explanatory diagram of an image of a grayscale font. Engineering: binary font memory, 2: gradation difference font data memory, 3: gradation data table, 4...
- Control calculation circuit, 5... gradation font buffer.

Claims (1)

[Claims] The present invention is characterized by comprising a font storage means for storing font data as bitmap data, and a gradation difference font data storage means for storing difference data for gradation expression and its position information on the bitmap. Font generator with gradation.