JPH10312185A - Character font reproducing method, tape printer and document creator - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To improve decoding efficiency by reducing the amount of data to be handled, and to reproduce characters clearly without increasing the memory capacity so much even if the character font size is plural. . In the character font reproducing method and the tape printer, a bitmap font of at least two characters having different sizes is decoded and reproduced. And
When decoding bitmap font data of a character with a large number of dots, as a reference pixel of the bit to be decoded,
The information of the bitmap font of the same character having a small number of dots already decoded is used, or the information of the reference font having the same size as the character having a large number of dots is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of reproducing a character font used in a tape printer or a document creator and the like, and to an improvement of a tape printer or a document creator incorporating the character font reproducing function. .

[0002]

2. Description of the Related Art Conventionally, characters used in a tape printer or the like are, for example, 16 × 16 dots, 24 × 24 dots,
It is composed of character fonts of a plurality of sizes such as 36 × 36 dots. In a normal device, the number of bitmap fonts corresponding to the number of characters is provided for each size. This is because if a character font of one size, for example, a character font of 16 dots is simply doubled vertically and horizontally, a character font of 32 dots in a beautiful shape will not be obtained. That is, simply doubling the characters results in a jagged and unusable character. Therefore, if the number of characters is 3,000, 3,000 characters in 16 dots
The number of bitmap fonts obtained by multiplying the number of characters by the number of character fonts, such as 0, 24 dots, and 3,000, is stored in the memory.

In the case of such an apparatus, an extremely large amount of memory is required when the type of character font and the number of fonts increase. For example, if the font A is a character font of four sizes and the font B is a font of four sizes again, in the above example, 3,000 × 4
× 2 requires a total of 24,000 bitmap fonts.

On the other hand, the number of points used in a word processor or a personal computer is limited to a predetermined range, so that only one or two types of character fonts are stored as bitmap data. The character font of the size is proportionally calculated from the data to obtain a character font of a predetermined size. Such a method is also employed in a tape printer when the quality of characters is not so important. Note that the character modification of double-width or quadruple-width characters used in word processors, personal computers, and the like simply expands a character font of a specific size to the size. As described above, a document creator such as a word processor in which the quality of characters is not so important has many types of fonts, not types of sizes of character fonts. Also, recently, personal computers having a large number of outline fonts have appeared in consideration of character quality.

For this reason, in a word processor or the like, a compression technique disclosed in JP-A-7-199894 is known as a technique for suppressing an increase in the amount of character font data. In this technology, an outline font of a character in a predetermined typeface is set as a reference character font, others are set as compression target character fonts, and a “displacement” of coordinates of the compression target character font with respect to the reference character font is detected, and the “displacement” is detected. Utilization is used to suppress an increase in the amount of memory. In other words, the frequency of occurrence of the "shift" data is biased, and a compressed code string in which redundant portions are suppressed is generated according to the frequency of occurrence, and the compressed code string is used to replace the coordinate data of the character font to be compressed. A character font is generated, and this compressed character font is stored in a memory together with a reference character font.

On the other hand, in recent years, a technique using an entropy encoder and a decoder has attracted attention as one of data compression techniques. As one of the entropy coding and decoding techniques, for example, there is one using an arithmetic coding and decoding technique. The outline of this technology is described in, for example, JP-A-62-185413 and JP-A-63-7432.
No. 4, JP-A-63-76525 and the like.

FIG. 16 shows a conventional encoding system 150 and decoding system 160 using such a technique. The encoding system 150 includes the line buffer 15
1 and an entropy encoder 152.
The input pixel data 100A of the index is input to the line buffer 151 and the entropy encoder 152. As shown in FIG. 17, all of the pixel data 100A are raster-scanned and sequentially input as pixel data in the horizontal scanning order.

The line buffer 151 in the encoding system 150 creates reference pixel data A, B, C, and D for the pixel X to be encoded from the already input pixel data 100A as reference pixel generation means. That is, the line buffer 151 stores the history of n lines (often about 1 to 5 lines) when scanning an image. Each time the pixel data 100A of the encoding target pixel X is input, a series of pixel data including the immediately preceding pixel A and the surrounding pixels B, C, and D is used as the reference pixel data 110 as the entropy encoder 152. Output to.

The entropy encoder 152 is formed using, for example, a technique such as arithmetic coding or Huffman coding. Then, the reference pixel data 110 is used as a state signal, and the target pixel data 100A is converted into encoded data 200 and output.

On the other hand, the decoding system 160 includes a line buffer 161 and an entropy decoder 162. Here, the line buffer 161 and the entropy decoder 162 store the encoded data 200
Is decoded and output in a procedure completely opposite to that of the line buffer 151 and the entropy encoder 152 of the encoding system 150.

In this manner, the encoding system 150
And the decoding system 160 converts the pixel data 100A into the encoded data 2 using completely opposite algorithms.
00, and the encoded data 200 can be decoded into pixel data 100B and output. Therefore, this system is widely used for various applications.

However, such an entropy encoder 1
52 and the entropy decoder 162 require a number of encoding parameter tables corresponding to the number of states of reference pixel data. For this reason, the larger the number of reference pixels is set to increase the compression ratio, the larger the encoding and decoding parameter tables become. Therefore, there is a problem that the entropy encoder 152 and the entropy decoder 162 become large and expensive.

In order to solve such a problem, a technique is known in which the parameter table is reduced according to the number of states degenerated in the entropy encoder 152 and the entropy decoder 162.

The feature of the system for reducing the number of states is as follows.
As shown in FIG. 18, like the encoding system 150 and the decoding system 160 in FIG.
2 and the reference pixel data 1 in the entropy decoder 162.
10 is input as a state signal. At the time of input, the state signal 140 is input to the line buffer 15.
1, 161 is generated by the state reduction units 153, 163 for reducing the reference pixel data 110.

The state decompressors 153 and 163 degenerate the input reference pixel data 110 into a state signal 140 having a smaller number of bits, and the corresponding entropy encoder 1
52 and the output to the entropy decoder 162. Note that the predictors 154 and 164
If the pixel to be processed is a color, the memory has a color order table for converting color pixel data into a color order based on the appearance frequency of a color symbol and vice versa.

Note that degeneration is an operation of classifying the original state into the number of states after degeneration. This classification is performed by selecting the combination so that the entropy after classification (the average information amount for displaying one symbol) is minimized. Then, an identification bit is added to the number of states after degeneration, that is, the number of states after classification. This is the state signal 140.

By the way, as the compression table used for the state compression units 153 and 163, a compression table for specifying the relationship between the combination pattern of the reference pixel data 110 and the compression data is set, and the compression table is input using this compression table. There is a method of converting the combination pattern of the color symbols of the reference pixel data 110 into degenerated data and outputting it.

FIG. 19 shows an example of a degeneration operation performed using such a method. Here, in order to simplify the description, as shown in FIG. 19A, a case where a Markov model formed from three pixels A, B, and C is used as a reference pixel pattern for a pixel X to be coded. Will be described as an example.

The reference pixel is, as shown in FIG.
In the case of three color pixels, the combination patterns of the color symbols are five as shown in FIG. In other words, the pattern is classified into a total of five patterns: a pattern in which the color symbols of three pixels all match, a pattern in which only two color symbols match, and a pattern in which the color symbols of all pixels are different. .

Therefore, by using the table shown in FIG. 19B as the degeneration table of the state degeneration units 153 and 163, when a pixel is a color pixel having a 4-bit index code, a combination of three pixels is originally obtained. FIG. 19 shows the state of a possible 2 12 pattern.
The state can be reduced to the five states S1 to S5 shown in FIG. By doing so, the reference pixel data 1
10 can be effectively degenerated, and the number of states of the entropy encoder 152 and the entropy decoder 162 can be greatly reduced.

Incidentally, such a general method of arithmetic coding and decoding has already been described in the one-picture coding standard JBIG.
(International standard ISO / IEC11
544), pp. 26-44 and p44-p50, which are briefly described here as prerequisite techniques for describing the present invention described later.

FIG. 20 shows an example of the arithmetic code type entropy encoder 152 used in FIG. Note that the configuration of the arithmetic decoding type entropy decoder 162 is substantially the same as the configuration of the entropy encoder 152, and a description thereof will be omitted here.

The entropy encoder 152 includes an arithmetic operation unit 155 and an occurrence probability generation unit 156 functioning as a state storage. In the occurrence probability generation means 156, a state parameter table necessary for determining a symbol occurrence probability required for encoding is written. The above status parameters are specified by the input status signal. Then, the occurrence probability calculation parameter of the occurrence probability generation unit 156 is output to the arithmetic operation unit 155 with respect to the state parameter table specified by the state signal.

The arithmetic operation unit 155 performs entropy coding based on the occurrence probability input in this manner,
Input pixel data 100A or color order data 12
0 is converted to encoded data 200 and output. Then, the occurrence probability for the state signal is recalculated based on the value of the encoded pixel data 100A or the color rank data 120, and is input to the occurrence probability generation unit 156 as an operation parameter update value. By storing this update result in the table as the occurrence probability of the next data, the compression efficiency of the entropy encoder 152 is improved.

[0025]

However, the technique disclosed in Japanese Patent Application Laid-Open No. Hei 7-199894 is effective when a plurality of different fonts are held as outline fonts, but a plurality of fonts are used for one font as bitmap fonts. When you need a character font of size and you want to focus on character quality,
Requires a lot of memory. Also, Japanese Patent Application Laid-Open No. 7-19 / 1995
The technology indicated by 9894 is a technology relating to outline fonts, and cannot be applied to a technology for enlarging or reducing using bitmap data.

When the quality of the character is not emphasized, a character font of another size is obtained by proportionally enlarging and reducing the character font data of one size as in the prior art. However, according to this method, as described above, when enlarged, the characters are jagged, and high-quality characters cannot be obtained.

In a tape printer, a document creator, and the like, there are certainly requests for a plurality of typefaces.
Multiple font sizes are also required for each typeface. Such a demand is contradictory to a demand for a lower price and a smaller size for a tape printing apparatus when emphasizing the quality of a character, and is a major obstacle to a lower price and a smaller size. .

Further, in a document creator such as a word processor or a personal computer, a usable memory or a storage device may be large to some extent. Therefore, it is difficult to individually hold character fonts of a plurality of sizes composed of bitmap data.
At present it is not so burdensome. However, in many cases, only one size font of one font requires a memory capacity of several Mbytes. When a large number of fonts are provided, bitmap data of character fonts of a plurality of sizes are individually stored. The possession also poses a major problem in terms of memory capacity.

Further, when encoding or decoding is performed by greatly reducing the number of states by using a reference pixel using method as shown in FIG. 17 or a Markov model reference pixel as shown in FIG. In the method, a reference pixel immediately before the pixel X to be encoded, that is, a Markov model or the like input to the entropy encoder 152 or the entropy decoder 162 until the pixel indicated by A in FIG. The context cannot be determined. For this reason,
The encoding and decoding processes have to wait until the context is determined, which limits the high-speed operation. In addition, by using reference pixels for compression, the compression ratio is increased and the decoding efficiency is also increased, but the bitmap data itself has an extremely large capacity, and the data amount is still large. Has become.

The present invention can improve decoding efficiency by reducing the amount of data to be handled and, even if character fonts have a plurality of sizes, can reproduce characters clearly without significantly increasing the memory capacity. It is an object to provide a method and a tape printing device and a document maker.

[0031]

In order to achieve the above object, according to the first aspect of the present invention, there is provided a character font reproducing method for decoding and reproducing at least two bitmap fonts of characters having different sizes. When decoding bitmap font data of a large number of characters, bitmap font information of the same character having a small number of dots already decoded is used as a reference pixel of a bit to be decoded.

Therefore, a character font having a large number of dots can be reproduced in a beautiful form by using a font of the same character having a small number of dots which has already been decoded, and the decoding efficiency can be improved. Also, by adopting this method, the compression ratio at the time of data generation prior to decoding can be increased, the memory of the device for reproducing character fonts can be reduced in capacity, and the device can be reduced in cost and size. Furthermore, if the memory capacity is the same, character fonts of various sizes can be loaded. Also, as the reference pixel, it is possible to refer to bitmap information of a portion corresponding to a character having a lower size and peripheral pixels generated after the corresponding pixel.
That is, in the case of the Markov model, it is possible to refer to even information of a pixel located after the target pixel to be decoded, so that extremely efficient decoding can be performed.

According to a second aspect of the present invention, there is provided a character font reproducing method for decoding and reproducing at least bitmap fonts of characters of two different sizes.
When decoding bitmap font data of a character with a large number of dots, as a reference pixel of the bit to be decoded,
Information of a reference font having the same size as a character having a large number of dots is used.

Therefore, a character font having a large number of dots can be reproduced in a beautiful form by using a reference font having the same size as the number of dots, and the decoding efficiency can be improved. Also, by using this reproducing method, the compression ratio at the time of data generation prior to decoding can be increased, and the memory of the device for reproducing character fonts can be reduced in capacity, cost and size can be reduced. If the memory capacity is the same, character fonts of various types can be loaded. Furthermore, as reference pixels, bitmap information of a corresponding portion of a reference font having the same size and peripheral pixels generated after the corresponding pixel can be referred to. That is, in the case of the Markov model, it is possible to refer to even information of a pixel located after the target pixel to be decoded, so that extremely efficient decoding can be performed.

Further, the third aspect of the present invention is the first aspect of the present invention.
In the described character font reproduction method, when decoding bitmap font data of a character having a large number of dots, information of a reference font having the same size as the character having a large number of dots is also used as a reference pixel of a bit to be decoded. We are using. As described above, at the time of decoding, two pieces of information, that is, the bitmap font information of the same character that is already decoded with a small number of dots and the reference font information of the same size as the number of dots to be reproduced are used. Therefore, decoding efficiency is further improved. Further, as the reference pixel, it is possible to refer to each bitmap information of a corresponding part of the same character of lower size or a reference font of the same size, and peripheral pixels generated after the corresponding pixel. That is, in the case of the Markov model, it is possible to refer to even information of a pixel located after the target pixel to be decoded, so that extremely efficient decoding can be performed.

According to a fourth aspect of the present invention, there is provided an input means for inputting character data and the like, a storage means for storing input document data, and a display means for displaying the input document data and the like. At least two different sizes of a tape printing apparatus including a transport unit that transports a tape-shaped recording medium and a printing unit that prints document data or the like stored in a storage unit on a recording medium transported by the transport unit. A character font reproducing means for decoding and reproducing the bitmap font of the character is provided, and when decoding bitmap font data of a character having a large number of dots,
As a reference pixel of a bit to be decoded, bitmap font information of the same character with a small number of dots already decoded is used.

Therefore, a character font having a large number of dots can be reproduced in a beautiful form by using a bitmap font of the same character having a small number of dots which has already been decoded, and the decoding efficiency can be improved. Also, if this tape printer is adopted, the compression rate at the time of data generation prior to decoding can be increased, the memory capacity can be reduced,
If the device can be reduced in cost and size and have the same capacity, character fonts of various types can be loaded. Furthermore, as the reference pixel, it is possible to refer to bitmap information of a portion corresponding to a character having a lower size and peripheral pixels generated after the corresponding pixel. That is, in the case of the Markov model, it is possible to refer to even information of a pixel located after the target pixel to be decoded, so that extremely efficient decoding can be performed.

Further, the invention according to claim 5 includes an input unit for inputting character data and the like, a storage unit for storing input document data, a display unit for displaying the input document data and the like, In a tape printing apparatus comprising: a transport unit that transports a tape-shaped recording medium; and a printing unit that prints document data and the like stored in the storage unit on the recording medium that is transported by the transport unit. A character font reproducing means is provided for decoding and reproducing bitmap fonts of three different sized characters, and when decoding bitmap font data of a character having a large number of dots, a dot is used as a reference pixel of a bit to be decoded. The information of the reference font having the same size as the large number of characters is used.

Therefore, a character font having a large number of dots can be reproduced in a beautiful form and the decoding efficiency can be improved by using a reference font having the same size as the number of dots. Also, by using this tape printer, it is possible to increase the compression ratio at the time of data generation prior to decryption, and to reduce the capacity of the memory, reduce the cost and size, and, if the capacity is the same, increase the number of memories. Character fonts of various sizes can be loaded. Furthermore, as reference pixels, bitmap information of a corresponding portion of a reference font having the same size and peripheral pixels generated after the corresponding pixel can be referred to. That is, in the case of the Markov model, it is possible to refer to even information of a pixel located after the target pixel to be decoded, so that extremely efficient decoding can be performed.

Further, the invention according to claim 6 is based on claim 4
When decoding bitmap font data of a character with a large number of dots in the described tape printer, information of a reference font having the same size as the character with a large number of dots is also used as a reference pixel of a bit to be decoded. doing.
As described above, at the time of decoding, a bitmap font of the same character having a small number of dots already decoded and a reference font having the same size as the number of dots to be reproduced are used.
Since one is used, the decoding efficiency is further improved. Further, as the reference pixel, it is possible to refer to the bitmap information of the corresponding portion of the same character having the lower size or the reference font having the same size, and peripheral pixels generated after the corresponding pixel. That is, in the case of the Markov model, it is possible to refer to even information of a pixel located after the target pixel to be decoded, so that extremely efficient decoding can be performed.

According to a seventh aspect of the present invention, there is provided an input means for inputting character data, a storage means for storing the input character data, a display means for displaying the input character data, A character font reproducing means for decoding and reproducing at least two bitmap fonts of characters having different numbers of dots in a document creator having a printing means for printing a character having a large number of dots. When decoding bitmap font data, bitmap font information of the same character with a small number of dots already decoded is used as a reference pixel of a bit to be decoded.

Therefore, a character font having a large number of dots can be reproduced in a beautiful form by using a bitmap font of the same character having a small number of dots which has already been decoded, and the decoding efficiency can be improved. In addition, when this document creator is used, the compression rate at the time of data generation prior to decoding can be increased, the memory capacity can be reduced, the apparatus can be reduced in cost and size, and if the apparatus has the same capacity, Thus, character fonts of various types can be loaded. Further, as a reference pixel,
It is possible to refer to the bitmap information of the corresponding portion of the same character having the lower size and the peripheral pixels generated after the corresponding pixel. That is, in the case of the Markov model, it is possible to refer to even information of a pixel located after the target pixel to be decoded, so that extremely efficient decoding can be performed.

Further, according to the present invention, there is provided an input means for inputting character data, a storage means for storing the input character data, a display means for displaying the input character data, A character font reproducing means for decoding and reproducing at least two bitmap fonts of characters of different sizes, and printing means for printing bitmap fonts of characters having different sizes as reference pixels of bits to be decoded. And information of a reference font having the same size as a character having a large number of dots.

Therefore, a character font having a large number of dots can be reproduced in a beautiful form by using a reference font having the same size as the number of dots, and the decoding efficiency can be improved. Also, with this document maker,
As long as the compression rate at the time of data generation prior to decoding can be increased, the memory capacity can be reduced, the price can be reduced and the size can be reduced, and character fonts of various sizes can be loaded if they have the same capacity. Can be done. Furthermore, as reference pixels, bitmap information of a corresponding portion of a reference font having the same size and peripheral pixels generated after the corresponding pixel can be referred to. That is,
Speaking of the Markov model, it is possible to refer to even information of a pixel located after the target pixel to be decoded, so that extremely efficient decoding is possible.

According to a ninth aspect of the present invention, in the document creator according to the seventh aspect, when decoding bitmap font data of a character having a large number of dots, a dot reference pixel is used as a reference pixel of the bit to be decoded. Information of a reference font having the same size as a large number of characters is also used. As described above, at the time of decoding, since two bitmap fonts, which are already decoded and have the same number of dots and have the same size as the number of dots to be reproduced, are used, the decoding is performed. Efficiency is further improved. Further, as the reference pixel, it is possible to refer to the bitmap information of the corresponding portion of the same character having the lower size or the reference font having the same size, and peripheral pixels generated after the corresponding pixel. That is, in the case of the Markov model, it is possible to refer to even information on a pixel located after the target pixel to be decoded, so that extremely efficient decoding can be performed.

According to the character font reproducing method of the present invention, character fonts of a plurality of sizes can be reproduced in a beautiful form without significantly increasing the memory capacity, and the decoding efficiency can be improved. For this reason, tape printers and document creators incorporating this playback function can achieve low capacities and low prices, but also play back character fonts of various sizes in a clear form, and can print many characters and many typefaces. A device that can reproduce characters.

[0047]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. This embodiment shows a tape printer, and the character font reproducing method of the present invention will be described together with the description of the function of the tape printer.

First, a tape printer 1 according to a first embodiment of the present invention will be described with reference to FIGS. The tape printer 1 has a keyboard 2 serving as input means at a front portion on the upper surface thereof, and covers 3 and 3 at a rear portion.
Is attached. On the keyboard 2, a character key group 4 including alphabet keys, symbol keys, and the like, and a function key group for designating various operation modes and the like are arranged. The function keys include cursor movement keys 5, 6, 7, and 8 for moving the cursor left and right and up and down, a print key 9 for starting a printing operation, and a selection key 10 for setting various modes. include.

When the lids 3 and 3 are opened, the mounting portion 12 of the tape cartridge 11 is exposed as shown in FIG. The tape cartridge 11 mounted on the mounting portion 12 has a tape 1 serving as a tape-shaped recording medium having a fixed width inside.
3 is built-in. The tape 13 has a configuration in which an adhesive surface is formed on the back surface and the adhesive surface is covered with a release paper. An ink ribbon 14 is stored in the tape cartridge together with the tape 13. The tape 13 and the ink ribbon 14 are attached to a window 16 formed in the case 15.
Are transported in a mutually overlapping state at the position
The transport path is configured so that only 3 is discharged outside and the ribbon 14 is wound inside.

A thermal head 17 serving as a printing means is disposed on the side of the mounting section 12. When the tape cartridge 11 is mounted on the mounting section 12, the thermal head 17 is provided.
Is applied to the back surface of the ink ribbon 14 exposed from the window 16 of the tape cartridge 11. Therefore, desired characters and the like are printed on the surface of the tape 13 by driving the thermal head 17 to generate heat. The mounting unit 12 also includes the mounted tape cartridge 1.
A drive shaft 18 and the like, which are mechanically connected to a driven portion in the printer cartridge 1 and serve as a conveying unit, are arranged. When these are driven, the tape 13 and the ink ribbon 14 in the mounted tape cartridge 11 are Is carried out.

At a position adjacent to the mounting section 12, a liquid crystal display section 19 serving as display means is mounted. The display screen 20 of the liquid crystal display unit 19 has a size capable of displaying four lines. The portion of the lid 3 facing here is a transparent window 21, and the display screen 20 can be viewed through the window when the lid 3 is closed.

Next, the overall configuration of the control system of the tape printer 1 of this embodiment will be described with reference to FIG.

The control system includes a CPU 31, a ROM 32,
The control circuit 30 mainly includes a RAM 33 and a character generator ROM 34. And
The keyboard 2 is connected to the input port side of the control circuit 30. On the other hand, on the output port side of the control circuit 30,
Thermal head 1 via a driver 41 for driving the head
7, and the liquid crystal display unit 19 is connected via a driver 42 for driving the display. Where CPU
Reference numeral 31 also serves as character font reproducing means.

The ROM 32 has a program memory area 35
Here, a control program for controlling the thermal head 17 and the liquid crystal display unit 19 is stored in correspondence with code data input from the keyboard 2.

The RAM 33 serves as storage means, and includes a text memory 36 for storing document data corresponding to the input document, a display document data memory 37 for holding the document data displayed on the liquid crystal display unit 19, and , CPU3
1 includes an area such as a register group 38 for temporarily storing the result of the arithmetic processing. The character generator ROM 34 stores a dot pattern composed of bitmap data of characters and symbols prepared in the tape printing apparatus 1. When code data for specifying characters and the like is given, Output the corresponding dot pattern.

The printing resolution of the tape printer 1 is as follows.
It is 200 dpi. The basic character configuration is 16 × 16 dots, and the character font data of that size is stored in the character generator ROM 34 for each font as basic compressed data 50 by the entropy encoder 53 similar to the conventional one. I have. The basic compressed data 50 is a bitmap font of the 0th character, and here is a bitmap font of a character having a small number of dots.

The character generator ROM 34 further stores first compressed data 51 and second compressed data 52 shown in FIG. First compressed data 51
Is used to reproduce a 32 x 32 dot character font (first character bitmap font).
As shown in FIG. 4, data of a character font of 32 × 32 dots is compressed and encoded by an entropy encoder 53 using a character font of 16 × 16 dots as a context (details will be described later). ).

The second compressed data 52 is 64 × 64
Data obtained by compressing data of a dot character font (second character bitmap font) using the 32 × 32 dot character font as a context by the entropy encoder 53 (details will be described later). .
Each of the entropy encoders 53 has the same configuration. Therefore, the basic compressed data 50, the first compressed data 51, and the second compressed data 52 may be generated by one entropy encoder 53.

A character font of 16 × 16 dots and 32 ×
FIG. 6 shows the relationship between the 32 dot character font and the relationship between the 32 × 32 dot character font and the 64 × 64 dot character font. That is, if the original data is one, and if the character is twice as large in length and width, the corresponding portion has four data. In general, when the original pixel is one black, the corresponding four pixels in the case of a character twice as large in each of the vertical and horizontal directions are often black, and when the original pixel is one white, The corresponding four pixels are often white (see FIG. 6).

Here, the first compressed data 51 and the second compressed data 52 are generated outside the tape printer 1 in the same manner as the generation of the basic compressed data 50.
It is input to and stored in the character generator ROM 34 together with 0. For example, when storing the character of "forest", the same character "forest" is referred to with a small number of dots, compressed (as a context), and the data is input to the character generator ROM.

On the other hand, CP which is also a character font reproducing means
The U31 has a built-in or connected entropy decoder 54 shown in FIG. The reproduction control of the character font in the CPU 31 is performed as follows.

When reproducing characters of 16.times.16 dots, the basic compressed data 50 is input to the conventional entropy decoder 54 and reproduced (details will be described later). 32x3
When reproducing a two-dot character, the already decoded 16
Using the × 16 dot character font as a context, the first compressed data 51 is reproduced by the entropy decoder 54 as a 32 × 32 dot character font (first character bitmap font) (details will be described later).

When reproducing a character of 64 × 64 dots, data of a character font of 32 × 32 dots is obtained by the above-mentioned steps, and then entropy decoding is performed using the data of the character font of 32 × 32 dots as a context. The device 54 reproduces a 64 × 64 dot character font (second character bitmap font).
The reproduced data is transmitted to the thermal head 17 via the driver 41 for driving the head, and the character font of each size is printed on the tape 13. Each data is transmitted to the liquid crystal display unit 19 via the display driving driver 42 and displayed. Note that the driver 42 may be configured to display a character font different from the character font printed by the thermal head 17. That is, since the character quality is not considered to be a problem in the liquid crystal display unit 19, 32 × 32 dots or 64 × 6 dots
The display of each character of 4 dots may be performed by simply enlarging the data of 16 × 16 dots by 2 times or 4 times.

The compression of the character font of 16 × 16 dots and the character font of 32 × 32 dots, etc.
In reproducing or decoding character fonts such as 2 × 32 dots and 64 × 64 dots, the following techniques are employed in order to increase the compression rate and increase the decoding efficiency.

That is, 16 × 16 dot character font data, 32 × 32 dot character font data, and 64 × 64 dot character font data are supplied to the encoding system 170 shown in FIG. The data is input as data 100A, compression-encoded by the entropy encoder 53, and output as encoded data 200. The output encoded data 200 is stored in the character generator ROM 34.

The encoding system 170 has basically the same configuration as the encoding system 150 shown in FIGS. The difference is that the data of the second reference pixel 130 is input to the entropy encoder 152 as a state signal or the like to increase the compression ratio.

The data of the second reference pixel 130 is 32
× 32 dot character font data and 64 × 64
The data of the dot character font is input and generated and used at the time of compression. And FIG. 7 (A)
In the lower-order font memory 120, character bitmap font data of 16 × 16 dots or 32 × 32 dots is stored. And, for example, 32 × 32
When trying to encode dot character font data, the same character 16 × 1
The data of the 6-dot bitmap font is retrieved and extracted and temporarily stored in the temporary font memory 122.

When encoding 32 × 32 dot character font data, the data in the temporary font memory 122 is used as a reference pixel of the data, that is, a context. That is, when encoding, the reference pixel 1 generated from the line buffer 151 as in the related art is used.
In addition to 10, the information is compressed using bitmap font information of the same character smaller than the character font of the size to be generated.

As described above, since the second reference pixel 130 exists in addition to the normal reference pixel 110, the compression ratio is increased. As the second reference pixel 130, information of a reference font having the same size (details will be described later) may be used instead of the method of using the character information one step lower as it is. Also, the second reference pixel 130 can be used for generating the state signal 140 using the state degenerate unit 153 as in the conventional example. In this case, the status signal 1
40, the method of using the second reference pixel 130 as it is, and in addition to the state signal 140, the second reference pixel 130
Into a state degenerate unit (not shown) to generate and use a second state signal.

On the other hand, the encoded data 200 encoded by the encoding system 170 is decoded by the decoding system 180 shown in FIG. 7B as character bitmap font data that becomes the pixel data 100B.
This decoding system 180 has basically the same configuration as the decoding system 160 of FIGS. The difference is that the data of the second reference pixel 130 is input to the entropy decoder 54 as a state signal or the like to increase the decoding efficiency.

The data of the second reference pixel 130 is 32
It is used when reproducing a × 32 dot character bitmap font or when reproducing a 64 × 64 dot character bitmap font. When reproducing a 32 × 32 dot character bitmap font, a 16 × 16 dot character bitmap font of the same character that has already been decoded is searched and extracted, and is stored in the temporary font memory 142.
The data is input to the entropy decoder 54 as data of the second reference pixel 130.

That is, when a 32 × 32 dot character is reproduced in the generated lower font memory 140 shown in FIG. 7B, the already decoded 16 × 16 dot character bitmap font data of the same character is read. Is stored, and 6
When a 4 × 64 dot character is reproduced, data of a previously decoded 32 × 32 dot character bitmap font of the same character is stored. Then, in the temporary font memory 142, data of the generated lower-order font memory 140 is retrieved and extracted, and temporarily stored as it is. And
When encoding the encoded data 200, data in the temporary font memory 142 is used as a reference pixel of the encoded data 200. That is, when encoding, the reference pixel 1 generated from the line buffer 161 as in the related art is used.
In addition to 10, reproduction is performed using information of a bitmap font of the same character smaller than the character to be reproduced.

As described above, since the second reference pixel 130 exists in addition to the normal reference pixel 110, decoding efficiency is improved. Here, as the second reference pixel 130, instead of using the information of the character at the next lower stage as it is, the information of the already decoded reference font of the same size (details will be described later) is used. Is also good. Further, the second reference pixel 130 can also be used for generating the state signal 140 by using the state degenerate unit 163 as in the conventional example. In this case, in addition to the state signal 140, a method of using the second reference pixel 130 as it is, and in addition to the state signal 140, the second reference pixel 130 is put in a state degenerate unit (not shown), and the second state signal is A method of generating and using it is conceivable.

As described above, since small character information is used in encoding and decoding, a large number of reference pixels and a large number of state signals can be obtained to improve the compression rate and increase decoding efficiency.
In addition, the fact that information in small characters can be used means that
For example, not only the information of the pixel before the pixel to be decoded but also the information of the pixel after the pixel can be used. That is, the decoding target pixel X in FIG.
8B, data L1 to L4, M1 to M4, N1 to N4, which are obtained by enlarging pixels of the same character smaller than the character including the pixel X twice vertically and horizontally as shown in FIG.
P1 to P4 can be used. Here, L1 corresponds to the position of the pixel C, L2 corresponds to the position of the pixel B, M1 corresponds to the position of the pixel D, L3 corresponds to the position of the pixel A, and L4 corresponds to the position of the pixel X.

In the prior art, the pixels A, B, C, D, etc., including the Markov model, were used as reference pixels. However, in the present embodiment, the original data L1, L2, L3, M1, etc. are also used. it can. Further, a pixel located at a position following the decoding target pixel X, which could not be referred to at all in the related art, for example, M3, N1, N2, P1, etc. can also be used as a reference pixel. Become.

When decoding the pixel X to be decoded shown in FIG. 8A, the original pixel may be used as it is. That is, the original pixel is informationally shown in FIG.
As shown in (C), when decoding the pixel X, not only the pixel L but also the pixels M, N, P, etc. are used. Also in this case, since the pixels M, N, and P all include the information of the pixel succeeding the encoding target pixel X, the decoding efficiency is high. Note that, as reference pixels, both a pixel that has been divided into small pieces (enlarged) and a pixel that has not been divided into small pieces (before enlargement) can be used. For example, when decoding the pixel N4, the surrounding pixels N1, N2, and N3 after the enlargement and the pixels L, N, and Q before the enlargement are used as reference pixels. In this case, the decoding efficiency is further improved.

Similar to the above-described decoding, the encoding, that is, the compression uses the information of the pixels of the same character with a small number of dots, so that the compression rate is high and the data amount is small. Become.

Next, a tape printer 61 according to a second embodiment of the present invention will be described with reference to FIGS. The basic configuration of the tape printer 61 is the same as that of the tape printer 1 of the first embodiment, and the same members are denoted by the same reference numerals and description thereof will be omitted or simplified. .

The tape printer 61 has a display section 62 made of liquid crystal on one lid 3 and the keyboard 2 which is hidden when the lid 3 is closed. Tape cartridge 11 or tape cartridge 1
Each structure of the mounting section 12 to which the tape printer 1 is mounted has a configuration similar to that of the tape printer 1 of the first embodiment. The control system is the same as the control system of the first embodiment shown in FIG.

The printing resolution of the tape printer 61 is 400 dpi. The basic character configuration is 16 × 16 dots as in the first embodiment, and the character font data of that size is converted into the basic compressed data 55 by the entropy encoder 58 similar to the first embodiment. Character generator R for each typeface
It is stored in the OM 34. The basic compressed data 55 is
As shown in FIG. 10, when creating compressed data of a predetermined character, a 16 × 16 dot character font of another character serving as a reference font is used as a context (details will be described later).

The character generator ROM 34 further stores first compressed data 56 and second compressed data 57 shown in FIG. First compressed data 56
Is used to reproduce a 32 x 32 dot character font (first character bitmap font).
As shown in FIG. 10, a character font of 16 × 16 dots and a character font of 32 × 32 dots of another character serving as a reference font are used as contexts,
This is data obtained by compressing and encoding 2-dot character font data by the entropy encoder 58 (described later in detail).

The second compressed data 57 is 64 × 64
Data of a dot character font (second character bitmap font) is converted into a 32 × 32 dot character font,
A character font of 64 × 64 dots of another character serving as a reference font is compressed and encoded by the entropy encoder 58 using as a context (details will be described later). Note that each entropy encoder 58 is
Both have the same configuration. Therefore, the basic compressed data 55, the first compressed data 56, and the second compressed data 57
May be generated by one entropy encoder 58.

Here, the first compressed data 56 and the second
The generation of the compressed data 57 is performed outside the tape printer 61 in the same manner as the generation of the basic compressed data 55, and is input to the character generator ROM 34 together with the basic compressed data 55 and stored. For example, in the case of storing the character of "Hayashi", the character of "Hayashi" of the same character with a small number of dots and the character which is the reference font for this "Hayashi", for example, the character of "Katsura" are referred to ) And compress the data into a character generator RO
This is done by inputting to M34. In this case, “Katsura” corresponds to a reference character serving as a reference font, and is used as a context when another character on the “tree” side is generated. The reference font may be bitmap data of a predetermined shape instead of specific characters.

On the other hand, the CP serving as the character font reproducing means
The U31 has a built-in or connected entrypy decoder 59 shown in FIG. The reproduction control of the character font in the CPU 31 is performed as follows.

When reproducing characters of 16 × 16 dots, the basic compressed data 55 is input to the entropy decoder 59, and reproduced using the already decoded or built-in 16 × 16 dot reference font as a context ( Details will be described later). When reproducing a character of 32 × 32 dots, the first compressed data 56 is entropy-decoded using the already decoded font of the same character of 16 × 16 dots and a reference font of 32 × 32 dots as a context. The character is reproduced as a 32 × 32 dot character font (first character bitmap font) by the device 59 (details will be described later).

When reproducing a character of 64 × 64 dots, data of a character font of 32 × 32 dots is obtained by the above-described steps. The 64 × 64 dot character font (second character bitmap font) is reproduced using the decrypted or built-in 64 × 64 dot reference font as a context.

The reproduced data is transmitted to the thermal head 17 via the head driving driver 41 in the same manner as in the first embodiment, and the character font of each size is printed on the tape 13. . Each data is transmitted to the liquid crystal display unit 19 via the display driving driver 42 and displayed.

The compression of the character font of 16 × 16 dots, the character font of 32 × 32 dots, etc.
In reproducing or decoding character fonts such as 2 × 32 dots and 64 × 64 dots, the following techniques are employed in order to increase the compression rate and increase the decoding efficiency.

That is, 16 × 16 dot character font data, 32 × 32 dot character font data and 64 × 64 dot character font data are supplied to the encoding system 171 shown in FIG. The data is input as data 100A, compression-encoded by the entropy encoder 58, and output as encoded data 200. The output encoded data 200 is stored in the character generator ROM 34.

The encoding system 171 has basically the same configuration as the encoding system 170 shown in FIG.
The difference is that the data of the third reference pixel 131 is input to the entropy encoder 58 as a state signal or the like to increase the compression ratio.

The data of the third reference pixel 131 is generated and used when compressing character bitmap font data of each dot number. And FIG.
The reference font memory 124 shown in FIG.
Reference font data serving as reference characters of 16 dots, 32 × 32 dots, and 64 × 64 dots is stored. Then, for example, when encoding data of a character font of 32 × 32 dots, a reference character serving as a reference font of the character is retrieved and extracted and temporarily stored in the temporary font memory 126.

When encoding the data of each character font, the data in the temporary font memory 126 is used as a reference pixel (context) of the data. That is, when encoding, the line buffer 1
In addition to the reference pixel 110 generated from 51 and the corresponding reference pixel 130 generated from the same character having a small number of dots, compression is performed using information on a reference font having the same size as the character font to be generated. doing.

As described above, since the second reference pixel 130 and the third reference pixel 131 exist in addition to the normal reference pixel 110, the compression ratio is increased. Note that the second reference pixel 130 and the third reference pixel 131 can also be used for generating the state signal 140 using the state degenerate unit 153 as in the conventional example. In this case, the status signal 1
40, a method of using the second reference pixel 130 and the third reference pixel 131 as they are, a method of putting the second reference pixel 130 and the third reference pixel 131 into a state degenerate unit (not shown) in addition to the state signal 140. , A second state signal may be generated and used.

On the other hand, the encoded data 200 encoded by the encoding system 171 is decoded by the decoding system 181 shown in FIG. 12B as character bitmap font data that becomes pixel data 100B. This decoding system 181 has basically the same configuration as the decoding system 170 of FIG. The difference is that the data of the third reference pixel 131 is input to the entropy decoder 59 as a state signal or the like to increase the decoding efficiency.

The data of the third reference pixel 131 is used for reproducing a character bitmap font of each dot number, for example, for reproducing a character bitmap font of 32 × 32 dots. × 32
The data of the reference font of the dot is retrieved and extracted, and is stored in the temporary font memory 146. Then, this data is input to the entropy decoder 54 as data of the third reference pixel 131. The reference font memory 1
The reference font that has already been decoded may be inserted into 44 (see the dotted line in FIG. 12), but only the reference font may be stored in advance according to the number of dots.

When the encoded data 200 is encoded, data of a reference font serving as a reference of a character to be decoded is retrieved and extracted from the data of the reference font memory 144 in the temporary font memory 146. Stored temporarily. After that, the data in the temporary font memory 146 is used as a reference pixel of the encoded data 200. That is, when encoding, in addition to the reference pixel 110 generated from the line buffer 161 as in the related art,
The reproduction is performed using the information of the bitmap font of the same character smaller than the character to be reproduced and the information of the reference font of the same size.

As described above, since the second reference pixel 130 and the third reference pixel 131 exist in addition to the normal reference pixel 110, decoding efficiency is improved. Note that the second reference pixel 130 and the third reference pixel 131 can also be used for generating the state signal 140 using the state degeneracy unit 163 as in the conventional example. In this case, in addition to the state signal 140, the second reference pixel 130 and the third
The method of using the reference pixel 131 as it is and the state signal 1
40, a second reference pixel 130 and a third reference pixel 1
It is conceivable to put 31 in a state degenerate unit (not shown) and generate and use a second state signal.

As described above, since information on small characters and information on a reference font having the same size are used at the time of encoding and decoding, the number of reference pixels and the state signal can be increased, and the compression ratio can be increased. It improves the decoding efficiency. In addition, the fact that information of a small identical character and information of a reference font having the same size can be used means that, as in the first embodiment, not only the information of the pixel before the pixel to be decoded but also that pixel Subsequent pixel information can also be used.

Next, a third embodiment of the present invention will be described with reference to FIGS. This embodiment is a tape printer similar to the tape printers 1 and 61 of the first and second embodiments, and differs in the type of the number of dots incorporated in the printer. . Therefore, the description of the configuration of the tape printing apparatus will be omitted, and the same members as those in the first and second embodiments will be described with the same reference numerals.

In the character generator ROM 34 of the third embodiment, reference compressed data 50, first compressed data 71, second compressed data 72, third compressed data 73, 4 compressed data 74 are stored. The first compressed data 71 is used for reproducing a character font of 24 × 24 dots (first character bitmap font) which is a 1.5-fold font. As shown in FIG. When the dot character font data is input to the entropy encoder 53 and compressed, 16 × 16 dot data of the same character is used.

As the second compressed data 72, data of a character font of 32 × 32 dots (second character bitmap font), which is a double font, is input to the entropy encoder 53, and the corresponding 16 characters of the same character are input. It is obtained by compressing using information of × 16 dots as context. Further, the third compressed data 73 is 32 × 32
Data of a 48 × 48 dot character font (third-order character bitmap font), which is 1.5 times the dot font, is input to the entropy encoder 53, and the corresponding 32 × 32 dot information of the same character is used as a context. Utilization and compression.

Further, the fourth compressed data 74 is 32 × 3
Data of a 6464 dot character font (fourth character bitmap font), which is a double font of 2 dots, is input to the entropy encoder 53, and the corresponding 32 × 32 dot information of the same character is used as a context. Obtained by compression. Each of the entropy encoders 53 has the same configuration. Therefore, each of the compressed data 50, 71, 72, 73, 74 may be generated by only one entropy encoder 53.

The generation of each of the compressed data 71, 72, 73, 74 is performed outside the tape printing apparatus in the same manner as the generation of the basic compressed data 50, and is input and stored together with the basic compressed data 50 into the character generator ROM 34. Can be Although various methods can be adopted as the compression method, arithmetic coding is employed here as in the first embodiment. Specifically, the same one as the encoding system 170 described in FIG. 7 is used.

Here, how to use information of a character having a small number of dots when compressing a character font having a number of dots 1.5 times the size will be described.

For example, 16 × 16 dot data, 3
It is assumed that 2 × 32 dot data has the data configuration shown in FIG. That is, the pixel W is white and the pixels X, Y, and Z are black. In order to represent such data with a dot number 1.5 times as large, it is necessary to divide four pixels into nine. For this reason, the tape printers 1 and 61 are divided into square pixels each composed of four pixels. That is,
Pixels W, X, Y, and Z are divided into nine new pixels S1 to S9. In order to use data of a pixel having a small number of dots, a method of using a pixel having a small number of dots as it is, a method of using information obtained by dividing a pixel having a small number of dots into nine pixels, and these two methods are available. There are a total of three methods of using the same at the same time. This is the same as in the first embodiment.

The following describes how to divide four pixels having a small number of dots into nine pixels. For example, four new pixels S1, S3, at the corner of a large number of dots
S7 and S9 represent pixels W, X, and
The colors are Y and Z. Therefore, the new pixel S1 is white, and the new pixels S3, S7, and S9 are black. The new pixel S2 has two original pixels W and X, the new pixel S4 has two original pixels W and Y,
The new pixel S6 determines the color with reference to the two original pixels X and Z, and the new pixel S8 determines the color with reference to the two original pixels Y and Z. In this embodiment, for example, by giving priority to black, the new pixel becomes white only when both are white. Therefore, FIG.
When (A) is data with a small number of dots, the new pixels S2, S4, S6, and S8 with a large number of dots are all black.

The central new pixel S5 has a small dot number of 4
The color is determined with reference to all the pixels W, X, Y, and Z. In this embodiment, black is prioritized, and if two or more original pixels are black, black is set. As a result, in the case of the data configuration of FIG. 15A, the new pixel S5 becomes black.

As described above, by using four pixels of a character font of 16 × 16 dots as nine pixels of a character font of 24 × 24 dots which becomes 1.5 times font, it becomes easy to use the data for compression. . This relationship can also be applied to a case where 32 × 32 dots are similarly used to compress a 1.5 × font 48 × 48 dot character font.

When dividing four pixels of a character having a small number of dots into nine pixels, the method of determining each pixel is as described above.
There are methods of using Y and Z themselves, referring to peripheral pixels after division, and referring to peripheral pixels before division. For example, when determining a new pixel S2 having a large number of dots, the pixels U,
V and new pixels SA and S around the new pixel S2.
B, SC, S1, S3, S4, S5, and S6 may be referred to. As a reference pixel at the time of division, various methods other than these can be adopted. The first
In the embodiment, one pixel of a character having a small number of dots is
Various methods can be employed for the method of determining each pixel when dividing into pixels.

On the other hand, the reproduction of the character font is performed as follows. Basically, reproduction is performed by the same algorithm and apparatus as in the first embodiment shown in FIG.
The difference is that the reproduction of the character font of 8 × 48 dots is added.

When reproducing characters of 16.times.16 dots, the basic compressed data 50 is directly input to the entropy decoder 54 and reproduced. When reproducing a character of 24 × 24 dots, the first compressed data 71 is decoded into a character font of 24 × 24 dots by the entropy decoder 54 using information of 16 × 16 dots as a context.
Similarly, a character of 32 × 32 dots is reproduced from the second compressed data 72 and information of 16 × 16 dots,
An 8-dot character is reproduced from the third compressed data 73 and 32 × 32 dot information, and a 64 × 64 dot character is
Reproduction is performed from the fourth compressed data 74 and information of 32 × 32 dots.

The system at the time of reproduction according to the third embodiment uses the same system as the decoding system 180 shown in FIG. Note that in determining colors when dividing four pixels into nine pixels, for example, determining white and black, the above-described respective criteria are set in a table, and the character generator ROM is used.
34 or another ROM or EPROM.

The above embodiments are only examples of preferred embodiments of the present invention, but the present invention is not limited to these embodiments, and various modifications can be made without departing from the spirit of the present invention. It is. For example, in the above-described first to third embodiments, the size of the character is set to 1.5 times that of the smallest character.
The present invention can be applied to characters of various sizes, such as 1.2 times, 1.4 times, and 1.7 times, although they are doubled, doubled, or a combination thereof. Further, the characters of each dot number are not the same in the vertical and horizontal directions. For example, the number of dots in the vertical and horizontal directions is twice as large as the vertical one, and twice as large as the vertical one. It is good as well.

Further, as reference characters having the same size as the reference font, it is preferable to extract one character from the same character, such as a crown or a side portion. Two or more characters may be extracted from the same character group as reference characters, or completely different characters in which some of the characters are not identical may be used as reference characters. Furthermore, a simple figure composed of a group of dots instead of characters may be used as the reference font.

Further, at the time of decoding, a reference font having a small number of dots may be used instead of the same character having a small number of dots as a reference. Further, the reference font having a small number of dots may be referred to in combination with the font described in each embodiment.

Further, in each of the above embodiments, an example is shown in which the character font reproducing method of the present invention is used in a tape printer, but the present invention can also be applied to a document processor such as a word processor or a personal computer.

[0117]

As described above, in the character font reproducing method according to any one of claims 1 to 3, even if the font size of the character is plural, the character font can be reproduced without increasing the capacity of the memory used so much. Size characters can be reproduced beautifully. Also, since the amount of data for the characters to be reproduced can be reduced, the reproduction speed can be improved despite good character quality. In addition, at the time of reproduction, information of characters having the same character and a small number of dots or information of a reference font having the same size is used, so that decoding efficiency is improved.

Further, in the tape printer according to the fourth and sixth aspects and the document creator according to the seventh to ninth aspects, the memory for the character bitmap data has a sufficiently compressed bitmap font of each dot number. Since the data is stored, characters of each dot number can be reproduced in a beautiful form. For this reason, it is possible to provide a tape printer or a document creator capable of reproducing high-quality characters at high speed despite low prices. In addition, at the time of reproduction, information of characters having the same character and a small number of dots or information of a reference font having the same size is used, so that decoding efficiency is improved.

[Brief description of the drawings]

FIG. 1 is an external perspective view of a tape printing apparatus according to a first embodiment of the present invention.

FIG. 2 is a perspective view of a main part of the tape printer of FIG. 1 in a state where a lid is opened.

FIG. 3 is a schematic block diagram illustrating a control system of the tape printing apparatus of FIG.

FIG. 4 is a diagram for explaining a method of generating compressed data for character reproduction input into the tape printer of FIG. 1;

FIG. 5 is a diagram for explaining a method of reproducing characters of various sizes by the tape printer of FIG. 1;

FIG. 6 is a diagram illustrating a pixel relationship of characters having different numbers of dots in the tape printer of FIG. 1;

FIGS. 7A and 7B are diagrams showing respective systems for encoding and decoding data used in the tape printer of FIG. 1; FIG. 7A shows an example of generating encoded data stored in the tape printer of FIG. 1; FIG. 2B is a diagram illustrating an encoding system, and FIG. 2B is a diagram illustrating a decoding system provided in the tape printer of FIG. 1.

8A and 8B are diagrams for explaining reference pixels when data is decoded by the tape printing apparatus in FIG. 1, wherein FIG. 8A shows the state of the encoding target pixel and the reference pixels, and FIG. The case where the pixel having a small number of dots is referred to when is increased, and the case where the pixel having a small number of dots is referred to as is shown in FIG.

FIG. 9 is a view showing a second embodiment of the present invention, and is an external perspective view in a state where a lid is opened.

FIG. 10 is a diagram for explaining a method for generating compressed data for character reproduction input into the tape printer of FIG. 9;

11 is a diagram for explaining a method of reproducing characters of various sizes by the tape printer of FIG. 9;

12A and 12B are diagrams showing respective systems for encoding and decoding data used in the tape printing apparatus of FIG. 9; FIG. 12A shows the generation of encoded data stored in the tape printing apparatus of FIG. 9; FIG. 10B is a diagram illustrating an encoding system, and FIG. 10B is a diagram illustrating a decoding system provided in the tape printer of FIG. 9;

FIG. 13 is a diagram for explaining a method of generating compressed data for a character font used in the tape printer according to the third embodiment of the present invention.

FIG. 14 is a diagram for explaining a character font reproducing method used in the tape printer according to the third embodiment of the present invention.

FIG. 15 illustrates a relationship between a large character (1.5 times characters) font and a small characters (1 times characters) font used in the tape printer according to the third embodiment of the present invention. FIG.

FIG. 16 is a block diagram of a conventional image encoding and decoding system.

FIG. 17 is an explanatory diagram of reference pixel data with respect to conventional encoding target pixel data.

FIG. 18 is a block diagram of a conventional image encoding and decoding system having a state degeneration unit.

FIG. 19 is a diagram showing an example of a conventional degeneration table.

FIG. 20 is an explanatory diagram of a conventional arithmetic code type entropy coder and entropy decoder.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tape printer 2 Keyboard (input means) 3 Tape (recording medium) 17 Thermal head (printing means) 18 Drive shaft (conveying means) 19 Liquid crystal display part (display means) 31 CPU (character font reproducing means) 33 RAM (storage) Means) 50 Basic compressed data 51 First compressed data 52 Second compressed data 53 Entropy encoder 54 Entropy decoder 55 Basic compressed data 56 First compressed data 57 Second compressed data 58 Entropy encoder 59 Entropy decoder 61 Tape printing device 120 Lower font memory 122 Temporary font memory 124 Reference font memory 126 Temporary font memory 130 Second reference pixel 131 Third reference pixel 140 Generated lower font memory 142 Temporary font memory 144 Reference font memory 146 Temporary font memory Li

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI G09G 5/22 670 G09G 5/26 630Z 5/24 620 B41J 3/12 C 5/26 630 G06F 15/20 562C

Claims (9)

[Claims] In a character font reproducing method for decoding and reproducing bitmap fonts of characters of at least two different sizes, decoding is performed when decoding bitmap font data of a character having a large number of dots. A character font reproducing method characterized by using bitmap font information of the same character already decoded and having a small number of dots as a bit reference pixel. 2. In a character font reproducing method for decoding and reproducing at least bitmap fonts of characters of two different sizes, when decoding bitmap font data of a character having a large number of dots, decoding is performed. A character font reproducing method characterized by using, as a bit reference pixel, information of a reference font having the same size as the character having a large number of dots. 3. When decoding bitmap font data of a character having a large number of dots, information of a reference font having the same size as the character having a large number of dots is also used as a reference pixel of a bit to be decoded. 2. The character font reproducing method according to claim 1, wherein the character font is reproduced. 4. An input means for inputting character data or the like,
Storage means for storing the input document data, display means for displaying the input document data, etc., transport means for transporting a tape-shaped recording medium, and document data stored in the storage means. A tape printing apparatus having a printing means for printing on the recording medium conveyed by the conveyance means, wherein at least character font reproducing means for decoding and reproducing bitmap fonts of characters of two different sizes is provided; When decoding bitmap font data of a large number of characters, information of the bitmap font of the same character having a small number of dots already decoded is used as a reference pixel of a bit to be decoded. Tape printer. 5. An input means for inputting character data or the like,
Storage means for storing the input document data; display means for displaying the input document data; transport means for transporting a tape-shaped recording medium; and document data stored in the storage means. A tape printing apparatus having a printing means for printing on the recording medium conveyed by the conveyance means, wherein at least character font reproducing means for decoding and reproducing bitmap fonts of characters of two different sizes is provided; A tape characterized in that when decoding bitmap font data of a large number of characters, information of a reference font having the same size as the character having a large number of dots is used as a reference pixel of a bit to be decoded. Printing device. 6. When decoding bitmap font data of a character having a large number of dots, information of a reference font having the same size as the character having a large number of dots is also used as a reference pixel of a bit to be decoded. 5. The tape printing apparatus according to claim 4, wherein: 7. Input means for inputting character data, storage means for storing input character data, display means for displaying the input character data, and printing for printing the character data on a recording medium And a character font reproducing means for decoding and reproducing bitmap fonts of characters of at least two different sizes, and decoding bitmap font data of a character having a large number of dots. In this case, as a reference pixel of a bit to be decoded, information of a bitmap font of the same character having a small number of dots that has already been decoded is used. 8. An input unit for inputting character data, a storage unit for storing the input character data, a display unit for displaying the input character data, and a print for printing the character data on a recording medium. A character font reproducing means for decoding and reproducing at least two bitmap fonts of characters having different numbers of dots, and reproducing bitmap font data of characters having a large number of dots. A document creator, characterized in that at the time of decoding, information of a reference font having the same size as a character having a large number of dots is used as a reference pixel of a bit to be decoded. 9. When decoding bitmap font data of a character having a large number of dots, information of a reference font having the same size as the character having a large number of dots is also used as a reference pixel of a bit to be decoded. The document creator according to claim 7, wherein: