KR960016738B1 - Method and apparatus for processing information - Google Patents

Abstract

No summary

Description

Information processing method and device

Fig. 1 is a block diagram showing a schematic configuration of a printer apparatus capable of performing compression and decompression processing of font data of this embodiment.

2 is a block diagram showing a schematic configuration of a display device capable of performing compression and decompression processing of font data of this embodiment.

Fig. 3 is a diagram showing the data structure of the ROM of the apparatus in this embodiment.

4 is a diagram showing a concrete example of the increase and the number of back dots of a character pattern according to the first embodiment of the present invention.

5 is a diagram for explaining a dot pattern corresponding to a predictive function value in the first embodiment of the present invention.

6 is a diagram showing prediction function values in the first embodiment of the present invention.

FIG. 7 is a diagram for explaining cut-out of font data in the first embodiment of the present invention. FIG.

8 is a diagram for explaining encoding of font data in an embodiment of the present invention.

Fig. 9 is a flowchart showing the process of increasing the number of back dots of font data and encoding in the first embodiment of the present invention.

FIG. 10 is a diagram showing a concrete example of the increase and the number of back dots of a character pattern according to the second embodiment of the present invention. FIG.

Fig. 11 is a diagram for explaining the process of increasing the number of back dots of font data in the second embodiment of the present invention.

Fig. 12 is a flowchart showing the process of increasing the number of back dots and encoding of font data in the second embodiment of the present invention.

Fig. 13 is a flowchart showing the process of increasing the number of back dots of font data and encoding in the third embodiment of the present invention.

14 is a diagram for explaining data showing the position of a hook dot in the third embodiment of the present invention.

FIG. 15 is a diagram for explaining data showing the following data in the third embodiment; FIG.

FIG. 16 shows the results of compressing the character fonts of FIG. 4 or FIG. 10 according to the third embodiment of the present invention. FIG.

Fig. 17 is a block diagram showing a printing apparatus with a compressed font on which the present invention is applied.

Fig. 18 is a diagram showing an internal block device of a printing device on which a compressed font is applied and a storage device of a display device according to the present invention.

FIG. 19 is a diagram of a prediction function in which (A) is a dot pattern transformed into a bag of a prediction function, (B) is a conversion table of a prediction function, and (C) is a diagram showing a technique of prediction function processing.

20 is a diagram showing processing results by a prediction function.

21 shows a code table of the fourth embodiment.

FIG. 22 is a flowchart showing a control procedure of the fourth embodiment. FIG.

Fig. 23 is a block diagram showing a display device on which a compressed font to which the present invention is applied is mounted.

FIG. 24 is a diagram showing processing results by an exclusive OR in the vertical and horizontal directions. FIG.

25 is a technique of longitudinal exclusive OR, (A) is a technique of lateral exclusive OR, and (B) is a technique of longitudinal exclusive OR.

FIG. 26 is a flowchart showing a control procedure of the fifth embodiment.

FIG. 27 is a flowchart showing a control procedure of the sixth embodiment.

FIG. 28 shows the coding scheme in the sixth embodiment, where (A) is the data representation method of the sixth embodiment, (B) is the representation method of the following data, and (C) is the sixth embodiment. Figure shows code data.

* Explanation of symbols for main parts of the drawings

101, 201: work memory 102, 202: CPU

103, 203: ROM104, 204: data receiving unit

105: bitmap memory 106: argument controller

107: printing mechanism unit 205: display memory

206: display control unit 207: display unit

The present invention relates to an information processing method and apparatus for compressing or decompressing font data displayed in a bitmap format.

In a printer apparatus and a display apparatus having font data constituting characters or figures by a plurality of dots, font data having a data size suitable for the performance of the apparatus is provided. For example, a printer device having a resolution of 180 dpi (dots / inch) requires font data of 24 dots vertically and 24 dots horizontally to print characters of 10 points of 10 CPI (character / inch) width. The number of bytes of font data per character is 72 bytes. Further, in order to print the same data with a 360 dpi printer device, font data of 48 bits in length and 48 bits in width is required, and the number of data is 288 bytes for one character in this case.

Such font data is stored in the ROM inside the apparatus in a dot format in accordance with the resolution of the display apparatus or printer apparatus described above, and sequentially read out in correspondence with the character code in accordance with the display command signal or the command signal from the host apparatus and the bitmap. After being deployed to, it is displayed or printed.

Such font data may vary in size depending on the type and number of characters, particularly for characters that have many fonts such as Chinese characters and require about 8000 font data per font. The amount of data is huge. In addition, as the resolution of the display device and the printer device described above increases, the amount of font data per character increases. As a result, more memory (memory element) is required to store the font data, which may increase the product cost and increase the size of the product.

The present invention has been made in view of the above-described conventional example, and an object thereof is to provide an information processing method and apparatus capable of compressing font data with high efficiency.

The present invention provides a conversion process of converting font data to increase one of zero or one data of bitmap font data, and data of increasing contiguous length and non-increased data of increased data in the converted font data. The present invention provides an information processing method and apparatus having a step of coating the number of to zero.

It is an object of the present invention to convert font data to increment either zero or one data of the bitmap font data, wherein the contiguous length of the increased data and the number of non-increased data in the converted font data is zero. An information processing method and apparatus for encoding are provided.

SUMMARY OF THE INVENTION An object of the present invention is to print or display a character / graphic font composed of vertical N lines and horizontal M lines by replacing a piece of white or black data with the other data by a certain technique, and converting the converted data. By performing the compression process of expressing the data as only white or black data, the generated compressed font can be significantly compressed with respect to the original original font data, and an information processing method and apparatus capable of reducing the font data capacity as a whole are provided. It is.

Example 1

Next, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, the present invention may be applied to a system composed of a plurality of apparatuses, or may be applied to an apparatus composed of one apparatus. It goes without saying that the present invention can also be applied to a system or an apparatus which is achieved by supplying a program for implementing the present invention.

1 is a block diagram showing a schematic configuration of a printer apparatus capable of compressing font data by the font compression method of the embodiment of the present invention. This device may be, for example, a Japanese word processor, or may be a workstation or a computer system.

In FIG. 1, 102 is a CPU for controlling the entire printer apparatus, and also has a function of expanding a compressed print. 101 is a work memory used when executing various control processes by the CPU 102, in order to expand the compressed font data, temporarily storing the compressed font data and temporarily storing the expanded font data. Numeral 103 denotes a ROM, which stores a control program and various data of the CPU 102, and further, stored as compressed font data compressed by the compression method of the present embodiment. 104 is a data receiving unit that receives data transmitted from a host device such as a host computer. Reference numeral 105 denotes a bit map memory, in which bitmap data recognized by the print mechanism unit 107 is stored. The bitmap memory 105 also develops image data in which the compressed font data are expanded as bit data, and is printed as a recording medium by the printing mechanism 107 based on the image data. In the printing control unit 106, control of the motor of the printing mechanism unit 107, driving control of the recording head, and the like are performed.

2 is a block diagram showing a schematic configuration of a display device which is an example of another device capable of compressing font data by the font compression method of this embodiment.

In FIG. 2, 202 is a CPU for controlling the entire display device, and also has a function of expanding the compressed font. 201 is used as a work area of the CPU 202 and can temporarily store various data. In addition, the compressed font data to be decompressed is temporarily stored in the work memory 201, and all data is converted among them during this decompression processing. 203 is a ROM which stores the control program and various data of the CPU 202, and also stores font data compressed by the compression method of this embodiment. 204 is a data receiving unit that receives data from a host device such as a host computer. 205 denotes a display memory, which stores display data displayed on the display unit 207. In this display memory 205, video data obtained by expanding font data is bitmap developed and displayed on the screen of the display unit 207. FIG. Reference numeral 206 denotes a display control unit which controls the brightness required for controlling the display on the display unit 207, the control of the display position, and the like.

The font data of this embodiment mounted on such a printer apparatus or display apparatus is stored in the ROM 103 203 with the data structure as shown in FIG. 3 is a diagram for explaining a data structure stored in the ROM 103 (203).

In FIG. 3, 301 is an area | region in which the control program of CPU102 (202) is stored. These devices are controlled according to this control program. 302 shows various tables in which data necessary for controlling the apparatus is stored. 303 indicates an area in which font data is stored, and this font data has a compressed font data portion, and a data table 304 for storing the compressed font data number and various data necessary for decompression of the font data. . It goes without saying that the ROM 103 203 may be composed of a plurality of ROMs depending on the data capacity, the ROM capacity, and the like.

In the present embodiment, in compressing font data, first, the back dots of the font data represented by the dots are increased, and then the data is compressed. Next, the compression process will be described.

5 to 7 show the processing for increasing the number of back dots of the font data in this embodiment.

First, as shown in FIG. 7 with respect to the original dot format font data (original font), when fonts of m × n dots are considered, the font data is surrounded by a pattern 701 having a thickness of one dot. As a result, a pattern of (m + 2) × (n + 2) is formed. The pattern is sequentially scanned using a 2 × 2 matrix pattern 501 to convert each dot from white to black, or from black to white.

5 and 6 are diagrams for explaining this dot conversion process. In the dot matrix 501 of FIG. 5 and FIG. 6, each dot is represented by a, b, c, d, and the dot located in the dot d is made into the object dot 501. FIG. The value of the target dot d predicted corresponding to the values of these dots a to c is shown in FIG. Thus, dot patterns corresponding to these prediction values are indicated by 502 to 509 in FIG.

Here, when the matrix 501 of FIG. 5 is applied to the dot pattern of FIG. 7 in turn, and the 2 × 2 dot pantone coincides with any of the patterns 502-509 of FIG. 5, The dot of the font data corresponding to the dot d (510) of the matrix 501 located is converted into the bag (0). On the other hand, when none of the patterns 502-509 match, the dot of the font data corresponding to the dot 510 is converted into black (1).

4 shows an example in which the dot pattern of the letter "H" is changed in this way.

Here, the periphery of the font data 401 is surrounded by a pattern 701 having a thickness of one dot, and the matrix 501 is sequentially applied to the font data. Returning to the uppermost data including the pattern 701), the same processing is performed to the last dot, and the value of each dot of the font data 401 is determined. The dot data converted in this way is indicated by 402. The dot data 402 shows that the number of back dots is increasing compared to the original font data 401. 403 shows an example of coding based on the rule shown in FIG. 8 based on this dot data 402.

In Fig. 8A, the number of data indicates the length (number of data) of continuous back dots, and the operand is determined as shown in the figure corresponding to the number of data. For example, if the back data is " 25 " dots consecutively and there is a hook dot thereafter, the operand is " 1 ", and the data portion is " 1 " from (25-24 = 1). Eighth (B) shows a data format of a code composed of an operand portion and a data portion, whereby the code at this time becomes "100001".

When the black dots are continuous for 4 dots, the number of back dots is displayed in a state where "0" is 3 dots continuous. That is, the data number "0" of the backdot is represented by the operand "1" and the data portion "0". As a result, a hook dot in which four dots are continuous is indicated as "100010001000". In this case, the remaining one dot is unnecessary when there is previous data, but is required when there is no data. In this case, the back data is encoded, and must be coded under the condition that hook data exists at the end of the data. Therefore, when the processing data is the last, it is determined that there is the last black dot and the processing ends. At the time of decompression, the last black is not represented because it exceeds the predetermined number of data.

Referring again to the code data 403 of FIG. 4, here, the converted dot data 402 is scanned and coded in the vertical direction. First, since there are "74" back dots up to the first black dot 401, FIG. From the figure, the operand is " 1 ", the data portion is (74-56 = 18) " 10010 ", and the code " 0001010010 " Next, since the black dots are continuous, the code is encoded as "1000" 412 as described above, and then 16 "dots" (413) are encoded because 16 back dots are continuous. The code 414 indicates the presence of subsequent black dots 420, and the next code 415 is a code " 100101 " that codes the number of back dots " 29 " from dots 420 to dots 430. . In the same manner, when the dot pattern 402 is encoded in the same manner, a total of 141 dots is expressed so that the dot pattern originally expressed by 576 bits is represented by 403.

Next, the compression process of the font data of this embodiment will be described with reference to the flowchart of FIG. The control flow for executing this process is stored in the ROM 103 (203).

First, the staff S1 reads font data for one character into the ROM 103 203 and writes it into the work area of the work memory 101. Subsequently, the procedure proceeds to step S2 where the font data stored in the work memory 101 is retrieved from the left end of the font data in units of a dot matrix 501 of 2x2 dots, and the pattern shown in FIG. See if there is a pattern that matches (502-509). When a matching pattern exists, processing is performed based on the above-described prediction function of converting the dot at the position corresponding to the dot 510 of the matrix 501 into a back dot. In step S1-step S3, this process is performed for all the dots of the original font data. Thereby, the dot pattern shown by 402 of FIG. 4 is obtained, for example.

Next, the flow advances to step S4 to scan the dot pattern created in steps S1-S3 in order to express the font pattern only with the back data, and counts the number of back dots until the dot is detected. When black dots are detected, the number of back dots up to that point is coded according to the coding scheme shown in FIG. Step S4-Step S6 performs the same processing on all of the converted dot patterns to code all the data.

When coding is completed in this manner, the flow advances to step S7 to write the compressed font data into the work memory 101 or another memory. The flow advances to step S8 to associate a character code with the compressed font data to create a font table. By proceeding with such a process, the original font data of "576" bits is compressed and stored into "141" bits, for example, as shown by code 403 of FIG.

Example 2

10 is a view for explaining the compression method of the second embodiment of the present invention. In the second embodiment, the number of back dots is increased by using the prediction function in the first embodiment, and in the second embodiment, an exclusive logical sum is performed on the up, down, left, and right directions of the font data. .

In Fig. 10, 710 denotes font data of the letter " H " composed of 24 dots x 24 dots, similarly to the first embodiment. 711 shows a result of increasing the number of back dots by the processing described later, and 712 shows a result of coding it.

FIG. 11 is a diagram for explaining the process of increasing the number of back dots by this exclusive logical sum. In FIG. 11 (A), an exclusive logical sum of left and right column data is first taken for data in the longitudinal direction of font data. Set the result in the data column on the right. All data processing is performed in units of columns, and the data columns after the calculation processing are also set in units of columns. In this case, the leftmost column data is not processed and the original font data remains. This process ends the font data width processing.

Next, as shown in the eleventh (B), an exclusive logical OR of data in the font data row direction is taken, and the result of setting the result in the lower row is sequentially executed for each row. As a result, the data in the top row is not processed and the original font data remains. If the font data is 24x24 font data, the number of processing in the lateral direction and the longitudinal direction is 24 times, respectively.

The result thus processed is indicated by 711 in FIG. 10, and the result of encoding it in the same manner as in the first embodiment described above is indicated by 712. FIG.

Next, the compression process of this second embodiment will be described with reference to the flowchart of FIG. The control program which executes this process is stored in the ROM 103 (203).

In step S11, original font data is read into the work memory 101 (201) similarly to step S1 of the first embodiment. Subsequently, the process proceeds to step S12, where an exclusive logical OR of the rows of the font data is taken, and the result is set in the lower row, and is written into the work memory 101 (201). In step S13, it is checked whether or not all data processing in the row direction has been completed. If the processing in the row direction ends, the process proceeds to step S14. This time, the exclusive logical sum of the column data of the font data is taken, and the result is written into the work memory 101 (201) so that the result is the right column data. In step S15, it is determined whether or not the processing for all data in the column direction is finished. In this way, when a dot pattern in which the number of back dots is increased is produced, in step S16 to step S20, it is coded in the same manner as in step S4-step S8 and stored in the memory.

By the processing shown in this flowchart, for example, code data 712 shown in FIG. 10 is obtained. In this case, the original font data was 579 bits, but is compressed to 171 bits of code data.

In the second embodiment, the font data is coded by increasing the back dot in the font data in a manner different from that in the first embodiment, but any method other than this may be used as the method of increasing the back dot. As described above, according to the present embodiment, the compression ratio of the font data is improved by increasing the number of back dots to scatter the back dots.

Example 3

Next, a third embodiment of the present invention will be described. 13 is a flowchart showing a process of the third embodiment, and a control program for executing this process is stored in the above-described ROM 103 (203).

First, in step 31, font data is read from the ROM 103 (203) and stored in the work area of the work memory 101 (201). Next, the flow advances to step S32 to perform the exclusive OR operation used in the above-described second embodiment in the transverse direction with respect to the adjacent dots of the font data, and determines whether or not the process is finished in step S33. Similarly, in step S34, the exclusive logical sum used in the above-mentioned second embodiment is performed between dots adjacent to each other in the longitudinal direction, and it is determined whether or not the processing is completed in step S35.

In this manner, the flow advances to step S36, and the black pattern is searched sequentially from the left in the row direction and the right in the up and down directions for the dot pattern in which the exclusive dot is increased in the vertical, horizontal and left directions. When black dots are found in this way, it is determined whether or not there are black dots adjacent to the black dots. As a result, in step S38, as shown in Figs. 14 to 15, the data indicating the direction in which the dot X direction (the horizontal direction) 140, the Y direction (the longitudinal direction) 141, and the next black data exist ( It is represented by three types of data consisting of 142). Next, the data shown in the black data direction is described continuously in the case shown in FIG. 14 when adjacent data are continuously present.

For example, as shown in FIG. 15, when the dot 150 designating the current position and the next black data 151 have a positional relationship as shown in the drawing, the data 150 shown in the direction of the next data is shown. As described above, only bits indicating the right direction of the direction data 142 are displayed as " 1 ". Moreover, when the direction is "upper side inclined to the right side", "lower side inclined to the right side", "upper side inclined to the left", "lower side inclined to the left", for example, the direction is "upper side inclined to the right" "," Is designated by turning on a plurality of bits corresponding to "right" and "upper" in the data 142. In any case of "left", "right", "up", and "down", only one bit of the direction data 142 of the next data is turned on (1). When all of the direction data 142 bits of the next data are '0', this indicates that there is no continuous data.

16 shows the result of encoding the letter "H" in FIG. 4 or 10 according to the third embodiment. Also in this case, the encoding algorithm is the same as in the above embodiment. This compresses, for example, 576 bits of font data into 288 bits of code.

In the above embodiment, the exclusive logical sum of the vertical and horizontal directions is used for the dot pattern to increase the back dot of the font data. However, even if the back dot is increased by using the prediction function or other method used in the above first embodiment, good.

In addition, the method of increasing the back dot is not limited to the method of the above-described embodiment, and various methods can be applied. In addition, in the present embodiment, the number of back dots is increased, but the number of black dots may be increased.

Although the present embodiment has described a method of increasing two back dots (predictive function method, exclusive logical sum of up, down, left, and right), any method may be used. Depending on the character type or the like, the white and black dots may be expressed alone without increasing the number of back dots.

In addition to the method of encoding, as shown in the third embodiment, any encoding process may be employed as long as the technique of focusing on and compressing black or white data in the font data is performed.

As described above, according to the present embodiment, the compression ratio is improved by encoding and compressing the font data into black or white data alone, and the capacity of the storage element of the device interrogating the font data can be reduced.

In addition, according to the font compression method of the present embodiment, the decompression processing can be simplified.

As described above, the present invention has the effect of compressing font data with high efficiency.

Example 4

Hereinafter, a fourth embodiment of the present invention will be described.

Fig. 17 is a block diagram of a printing apparatus capable of loading a compressed compressed font. 102 denotes a CPU for controlling the entire printing apparatus, and also has a function of expanding a compressed font. Reference numeral 101 denotes a work memory for temporarily storing compressed fonts to be decompressed, and all data conversion among them is performed during decompression processing. Numeral 103 denotes a ROM, which stores compressed fonts compressed by a compression method peculiar to the present embodiment, and data of various parameters used for programs and parameters for controlling the entire apparatus.

104 is a data receiving unit for receiving data from the host device. Numeral 105 denotes a print memory for storing data to be printed, and data in which the compressed font is expanded is also developed as bit map data on the print memory and printed on the recording medium. 106 denotes a print control unit for controlling data necessary for printing and controlling the print bit.

The font data mounted on the printing device is stored on a ROM having the internal structure of FIG. Here, 301 is a storage area of a program necessary for controlling the apparatus, and the printing apparatus is controlled according to this program. 302 is an area in which data necessary for controlling the apparatus is stored. 303 is a storage area for font data. This font data is composed of a compressed data portion and a data table 304 necessary for the number and compression of the compressed data.

Note that the ROM is also divided into a plurality of storage elements by the capacity of the data and the capacity of the ROM.

Fig. 19 describes the processing for increasing the number of back dots of font data. As shown in FIG. 19 (C) with respect to the original data of the font, font data, width width, and data of the font width of the font box are added by one dot to the left end of the font box, and the box-shaped area is divided into two bits up, down, left, and right. The pattern shown in Fig. 16 (A) is searched and replaced with the position processing target dot in d in Fig. 17 (A) when it matches the pattern. When it does not match this pattern, the position processing target dot of d of FIG. 19 (A) is replaced by black dot.

This will be described in more detail as follows.

First, one dot at the top of the vertical 48 * 48 font box, one dot at the left end, and NULL data are added to the font original data, and converted into font data formed of 384 dots as a whole. Next, data is sampled in the order of 2x2 masks from the upper left of the font original data that does not impose data (in the case of the first data, the lower right data of the 2x2 data is the upper right of the original font). , Upper left and lower left are all added NULL data.)

The sampled data is compared with the pattern in FIG. 19A, and if it is equal to one of them, the predicted data is set to "0", and if none is found, the predicted data is set to "1". Since the predictive function in () is adapted to the characteristics of the font, the data after the prediction from the original data increases by "0".

FIG. 19B shows the data of FIG. 19A in a table.

In the replacement of the back dots and the black dots, it is necessary to change the pattern depending on which data is increased. 19B of this embodiment is a data conversion table for increasing the back dot.

20 shows an example in which the number of back dots is increased by the method described in FIG. 19 using the letter "H". In the method of processing, the data is taken from the upper left and right sides of the data from two dots, and the data is replaced according to Fig. 19B. When the processing in one row is finished, the processing returns to the first head of the next row and processing continues, and the same processing is performed until the end of the data.

That is, Fig. 20 converts the data of the letter " H " using the above-described conversion method. The conversion procedure is placed at the bottom of the mask of 2x2 by one dot from the top left of the original font, checks whether it matches the pattern of Fig. 19A, and creates data after the prediction function.

In order to carry out the processing in the longitudinal direction, the second is the upper left and the left added data, the upper right and the previous processing target data, and the lower right becomes the current target data.

When the processing of one vertical line is finished, it moves to the right side and returns to the first image of the original font in the vertical direction (data with the upper right and the upper left added, the data at the same position in the longitudinal direction before the lower left one row, and the lower right processing) Target data).

This is repeated for the original font to form data after the prediction function. For example, in the case of the letter "H", since the first data is "0" and the data forming the mask of 2x2 is NULL data added other than the data to be processed, the upper left of Fig. 19A. The data after the prediction function is " 0 " in order to make it fit to ". &Quot; By repeating this processing, the data after the prediction function becomes 402 in FIG. 20, and the dot of data " 0 " It can be seen that is increasing.

The result is 402. Compared to 401, it can be seen that the back data is increasing. 403 is the result of coding the data according to the table shown in FIG. 21 after performing the process of increasing the bag. For example, when there are black dots after 25 dots of continuous data, it is "100001", and when black dots are continuous by 4 dots, it is "100010001000", and the black dots are represented without the back data.

In this case, the remaining one dot is unnecessary when the previous data is present, but is required when there is no data.

Although the above code is described with respect to the back data, it is always described under the condition that black data is at the end of the data.

When the processing data is the last, it is determined that there is a black dot at the end, and the processing ends. At the time of decompression, the last black is not represented because it exceeds the predetermined number of data.

Next, the control flow of this embodiment is explained using FIG.

In STEP 1, it corresponds to the reading part of the font data, and all data for one character is read into the work memory which is not shown in figure.

In step 2, the font data stored in the work memory is divided into two dots of up, down, left and right, and processed from the left of the font. The processing contents are as shown in FIG.

STEP 3 is to ensure that all data has been processed.

STEP 4 is a process for expressing only white data, and first calculates white data until black data is generated. In the stage where black has occurred, the white data up to that point is coded according to the table of Fig. 21 (STEP 5).

STEP 6 is a judgment step of determining whether all data has been processed.

STEP 7 writes to memory not shown as compressed data.

In STEP 8, tables are created according to the information corresponding to the compressed data.

By performing the above process, for example, 576 bits of data in the font original data can be represented by 141 bits as indicated by 403 in FIG.

In the present embodiment, the font data compression means mounted on the printing device has been described. However, the same compression process is possible by changing the order of data processing from the up-down direction to the left-right direction in the display device shown in FIG. .

In FIG. 23, reference numeral 202 denotes a CPU for controlling the entire display device, and also has a function of extending a compression font. 201 is a work memory for temporarily storing compressed fonts for decompression, and all data are converted among them during decompression processing. 203 is a ROM, which stores a compressed font compressed by a compression method peculiar to this embodiment, a program for controlling the entire apparatus, and data of various parameters used for display.

204 is a data receiving unit for receiving data from the host device. 205 is a display memory for storing data to be displayed, and data in which the compressed font is expanded is also developed as bitmap data on the display memory and displayed on the display medium. 206 is a display control unit for controlling the luminance necessary for displaying and controlling the display position.

Example 5

24 is an explanatory diagram showing a fifth embodiment of the present invention. The differences between the fifth embodiment and the first embodiment are as follows. In the process of increasing the back dot, the first embodiment uses a prediction function, whereas in the fifth embodiment, the processing is performed by performing an exclusive OR operation on the up, down, left, and right directions.

701 in FIG. 24 is indicated by the letter " H " composed of 24 dots × 24 dots as in the first embodiment.

As shown in FIG. 25A, as a method of increasing the back dot, an exclusive OR operation of left and right column data is first performed on the seed data of the font, and the data is set to the right data. All data processing is performed in units of columns, and the data after the processing is also set in units of columns. The data in the leftmost column is not processed, and the original data remains.

This process is repeated for the width of the font data to end the process.

Next, the exclusive OR operation is performed on the upper and lower data in the longitudinal direction of the font data, and the data is set on the lower side. The data in the top row is not processed, leaving the original data.

This longitudinal OR processing is repeated by repeating the length of the data. In the case of the present embodiment, the data count is 24 × 24, so that the number of repetitions in both sides is 24.

Next, the operation of this embodiment will be described using the flowchart of FIG. In step 1, original font data is read into the memory as in the fourth embodiment.

In STEP 2, the exclusive logical OR of the lateral direction is performed, and the memory is first written to the memory.

STEP 3 confirms that all data in the horizontal direction has been processed. Thereafter, an exclusive logical OR is performed in the longitudinal direction in STEP 4 to be written into the memory.

STEP 5 confirms that the processing of all data in the lateral direction has been completed.

STEP 6 to STEP 10 correspond to STEP 4 to STEP 8 of FIG. 22 showing the operation of the fourth embodiment, and the contents are the same.

By performing the processing described in the above control flow, the result shown in 703 in FIG. 24 is obtained, and 579 bits of font data can be compressed into 171 bits of code data as original data.

In this embodiment, the font data is coded by increasing the back dot in a manner different from that in the fourth embodiment, but any method of increasing the back dot can be used, and the number of the back dots increases, and the back dots are dotted. As a result, the compression ratio is further improved.

Example 6

27 shows the control flow of this embodiment. In step 1, font data is read and placed on a work memory, not shown. In STEP 2, the exclusive logical sum used in the above-mentioned fifth embodiment is performed in the horizontal direction, and in STEP 3, the end of the process is confirmed.

Similarly in STEP 4, the exclusive logical sum used in the above-described fifth embodiment is performed in the longitudinal direction, and in STEP 5, the end of the processing is confirmed.

In STEP 6, the hook dots are searched sequentially from the left in the left and right directions from the top in the left and right directions for data in which the back dot is increased by the above-described method of performing an exclusive OR in the upper and lower sinus directions. When a hook dot is found, it is searched whether there is a hook dot adjacent to the dot (STEP 7).

As a result, in STEP 8, it expresses with three types of data of the X direction (lateral direction), Y direction (vertical direction), and the direction of the next data of the dot shown in FIG. It is represented by three kinds of data of the direction of the next data. The direction data of the next data is described in succession as indicated in FIG. 28A when adjacent data are continuously present. The right inclined, right inclined, left inclined, and left inclined data are represented by a plurality of active data bits of multiple data.

In the data of the right, left, and top and bottom, only one bit of data in the direction of the next data becomes active. If all data in the next data direction are "0", it means that there is no continuous data.

28 (C) shows the result of encoding the letter “H” shown in 701 in FIG. 24 by the method of the present embodiment. That is, the original data is coded and compressed into 288 bits for 576 bits of data.

In this embodiment, an exclusive logical OR in the longitudinal direction is used for the method of increasing the back dot, but it is also possible to realize the prediction function and other methods of increasing the back dot used in the fourth embodiment.

Incidentally, the method of increasing the back dot is not limited to the method of the present embodiment, but may be in any manner.

In this embodiment, all the methods of increasing the back dot were used, but it does not matter as a method of increasing the black dot. As an embodiment of the present invention, a method of increasing two back dots (predictive function method, exclusive logical sum of up, down, left, and right) is described, but the method may be used in any method. It is also possible to express by white and black dots alone, without using the method of increasing the said back dot according to the kind of characters.

In addition, as shown in the third embodiment, as to the numbering method of encoding, if the technique of paying attention to the black or white data in the font data is carried out and compressed, it is possible to use any method of coding. There is no change in the effect.

As described above, according to the present invention, by encoding and compressing the font data with black or white data alone, the compression ratio is improved, and the capacity of the storage element of the font data can be reduced.

Further, according to the font compression process to which the present invention is applied, the decompression method of expanding the compressed font into a regular font is simplified in the apparatus equipped with compression to encode the font data into white or black data alone.

In this way, it is possible to represent a printing device and a display device having low cost and high functionality.

Claims (8)

A conversion process of converting font data to increment either zero or one data of the bitmap font data, and the successive length of the increased data in the converted font data and the number of data increased by zero. The information processing method characterized by having the process of coding as a function. The information processing method according to claim 1, wherein the conversion step increments any one of zero or one data of font data based on a prediction function. The information processing method according to claim 1, wherein the converting step increments any one of zero or one data of the font data according to an exclusive logical OR of rows or columns of font data. The information processing method according to claim 1, wherein the conversion step increases one of zero or one data of the font data according to an exclusive logical sum of dots adjacent to the row or column direction of the font data. Conversion means for converting the font data to increment one of zero or one data of the bitmap font data, and a continuous length of the increased data in the converted font data and the number of the data increased by zero. And encoding means for encoding the data. Data conversion means for replacing one piece of white or black data with the other data by converting the dot data of the character / graphic font composed of vertical N lines and horizontal M lines into the other data and converted into the data conversion means. And compression means for compressing and encoding the data by the Lanlens method in a form including continuous data and data indicating that there is no continuous data. An information processing apparatus according to claim 6, wherein said compression means forms a code without continuous data. The information processing apparatus according to claim 6, further comprising compressed font storage means for storing font data compressed by said compression means and compressed font decompression means for decompressing the compressed font.