JP3170125B2 - Method and apparatus for compressing character dot data - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data storage system for a dot pattern storage device for display characters and print characters.

[0002]

2. Description of the Related Art An electronic device having a function of displaying and printing characters has a circuit configuration as generally shown in FIG.
It is necessary to store character data in the 104 storage devices. If the character data is, for example, 32 × 32 dot matrix data, it is 1024 bits, that is, 128 bits.
A byte is required for each character, and as the number of characters increases, the data amount increases in proportion thereto. In particular, in the case of devices that handle Japanese, having a considerable number of kanji and kana is an important factor that affects the function and usability of the device, so it is necessary to store more character data. As a result, there is a disadvantage that the number and capacity of the storage devices are increased and the cost is high. Conversely, if the capacity of the storage device is limited,
As the character data amount increases, the area left in the program portion in the storage device becomes smaller, and there is a disadvantage that functions are not sufficiently incorporated. In any case, it is necessary to compress the character data to a small amount at least and store it in the storage device.

As a conventional compression technique, Japanese Patent Laid-Open No. 63-30 / 1988
The following technique, as found in 5389, is used.

(1) As shown in FIG. 2, dot data is decomposed into a plurality of blocks by dividing eight dot data into one block. In general, assuming that bit 0 corresponds to a white dot and bit 1 to a black dot, and that the upper direction of the figure is regarded as the upper bit, data from block 1 to block 4 is expressed as "2003E000" unless compression is performed.

By the way, a block in which at least one dot is a black dot is given a bit 1, and a block in which all the dots are white is given a bit 0 to make a discrimination. Block 1 to Block 4
As shown in FIG. 3, the compressed data a for
0 ". Next, only the data of the block to which bit 1 is given is represented by 1-byte data, and these are connected to form a data string, and this data string is referred to as compressed data b. The compressed data b for blocks 1 to 4 is “2003E0” as shown in FIG.

[0006] The compressed data a and the compressed data b are character dot data after compression. The compressed data a is the increase in the data amount, and the data amount of the block of bit 0 (the block in which all eight dots are white, hereinafter referred to as “white block”) in the compressed data b is the data amount. The difference is reduced, and the difference is compressed. For blocks 1 to 4, the data amount is reduced by 4 bits. In addition, since the number of blocks is 128 in the entire character in FIG. 2, the compressed data a is 128/8 = 16 (bytes).

Also, since there are 34 white blocks, the compressed data b is 128-34 = 94 (bytes).

Therefore, the data after compression becomes 94 + 16 = 110 (bytes).

As a result, the amount of compressed data is 128-110 = 18 (bytes).

The original character dot data can be uniquely decoded from the compressed data.

This compression method is hereinafter abbreviated as “discriminating decomposition method”.

This utilizes the fact that the character dot pattern contains many white dots.

(2) At a stage prior to the above-mentioned method (1), there is a method of further increasing the compression ratio by performing a certain processing on the character dot data.

In a character dot pattern , it is rare that white dots and black dots alternately appear every other dot, and that the same dot appears more than once in succession in many cases. There are features. Using this, instead of expressing character data as white dots as 0 and black dots as 1, the dot row is given a direction and the same dot as the previous dot is set to 0 and the previous dot is inverted. The resulting dot is expressed as 1. As a result, the number of 1 dots decreases, and the number of white blocks increases significantly. This reduces the capacity of the compressed data b and improves the compression ratio.

More specifically, dot data is generated by shifting the character dot data one dot to the left, and is superimposed on the original character dot data to form a logical exclusive sum (EXCLUSIVE).
−OR, hereinafter abbreviated as “XOR”. ). At this time, the data in the leftmost column that has been left-shifted and overflowed is discarded. In addition, the rightmost column is assumed to uniformly overlap white dots. The original character dot data can be uniquely decoded from the dot data after XOR. "Discriminant decomposition method"
The above steps for improving the efficiency of the above are hereinafter abbreviated as “XOR step”.

FIG. 4 shows an example in which the same data as in FIG. 2 is compressed by a “discriminating decomposition method” using an “XOR process”.

In the whole character shown in FIG. 4, the compressed data a is unchanged and becomes 128/8 = 16 (bytes).

Since the number of white blocks has increased to 58,
The compressed data b becomes 128-58 = 70 (bytes).

Therefore, the data after compression becomes 70 + 16 = 86 (bytes).

As a result, the amount of compressed data is 128-86 = 42 (bytes).

[0021]

However, there is still redundancy in data realized using the above method,
There has been a problem that an extra memory for storing data is required. An object of the present invention is to realize a higher compression ratio when storing character dot data in a printing apparatus.

[0022]

The character of claim 1 of the present invention
Dot data compression method corresponds to the pixels that make up characters
Corresponding to effective dots and the background pixels of the characters
Composed of a dot matrix of invalid dots
Target character dot data representing the character,
Block division to divide into blocks of predetermined multiple dots
Process and for each divided block, the block
When the effective dot is included in the
If one of them is assigned and the effective dot is not included
Assigning the other of the two predetermined values
The binary data indicating the predetermined binary value is stored in the block.
1st compression to create 1st compressed data arranged by the number of
The data creation step and each block containing the effective dots
The effective dot, the effective dot
One of the two is assigned, and the predetermined binary is assigned to the invalid dot.
By allocating the other of the predetermined
Binary data indicating a binary value is stored in each of the effective dots.
Second compressed data arranged by the total number of dots in the block
A second compressed data creating step of creating
Based on the first compressed data and the second compressed data,
Statement that creates character data by compressing character dot data
This is a compression method for character dot data.
A character that represents each character of a character including a number, alphabetic character, or number
Dot patterns commonly appearing in many of the dot data
Turns are defined as one or more specific dot patterns.
Before the division of the block, the character dot data
The specific dot pattern that encodes the specific dot pattern
Create specific dot pattern data
Data creation step, and a code as the specific dot pattern data.
The specified dot pattern is converted to the character dot data.
Data from the data to create the substitute character dot data.
A fixed dot pattern deleting step,
The division of the check is performed in place of the character dot data.
Character dot data.
You.

The character dot data according to claim 2 of the present invention.
The method of compressing data is effective de corresponding to picture element constituting the character
Invalid pixels corresponding to the pixel and the background pixel of the character.
The character is composed of a dot matrix composed of
For character dot data expressing
If the dots are different types of dots,
Effective dots are assigned, and when both are of the same type,
By assigning invalid dots, the character dots
Create exclusive pixel dot data of the same size as the data.
A step of creating another pixel dot data;
Block that divides the data into blocks of predetermined multiple dots.
Block division process, and for each divided block,
When the effective dot is included in the block,
One of the two values is assigned, and the effective dot is included
If not, assign the other of the two specified values
In this way, the binary data indicating the predetermined binary is
Create the first compressed data arranged by the number of blocks
A first compressed data creation step, including the effective dot
For each block, the effective dot is the predetermined binary value.
And assigning the invalid dot to the
By assigning the other of the two fixed values,
The effective dot includes binary data indicating a predetermined binary value.
The second pressure lined up by the total number of dots in each block
A second compressed data creation step of creating compressed data.
Based on the first compressed data and the second compressed data
The character data obtained by compressing the character dot data
A method of compressing character dot data to be created,
Represents each character including kanji, symbols, letters or numbers
Common to many of the character dot data
Set one or more dot patterns as specific dot patterns
Prior to creation of the exclusive pixel dot data,
The specific dot pattern included in the character dot data is
Identification to create coded specific dot pattern data
A dot pattern data creation step, and the specific dot pattern
Specific dot pattern coded as pattern data
Is deleted from the character dot data, and the substitute character
A specific dot pattern deletion process for creating
The apparatus further comprises: generating the exclusive pixel dot data,
Substitute character dot data instead of character dot data
Is performed for the target.

The character dot data according to claim 1 or 2
In the method of compressing data, the one or more specific dot patterns
With a predetermined dot width in the vertical or horizontal direction
Dot pattern that is continuous for the dot length of
preferable.

The character dot data according to claim 4 of the present invention.
The data compression method is based on the effective
Invalid pixels corresponding to the pixel and the background pixel of the character.
The character is composed of a dot matrix composed of
A predetermined number of character dot data
A block dividing step of dividing the block into blocks for each dot;
For each of the divided blocks,
When an effective dot is included, one of the predetermined two values
When the effective dot is not included,
By allocating the other of the predetermined two values,
The binary data indicating the predetermined binary is equivalent to the number of the blocks.
First compressed data creation for creating the first compressed data arranged side by side
Process and each block containing the effective dots.
The effective dot is one of the predetermined two values.
And assigns the invalid dot to the invalid dot,
By assigning the other, the predetermined binary value is indicated.
The binary data of each block containing the effective dots.
Creates the second compressed data arranged by the total number of dots of
And a second compressed data creating step.
Data based on the data and the second compressed data.
Character dot to create character data that is compressed data
A method for compressing data, the method comprising:
That is, the character dot data is circulated in a predetermined direction.
By the above, the number of blocks containing the effective dots is
Substitute character dots to be reduced compared to character dot data
A dot circulating step for creating data, and circulating in the predetermined direction.
Binary data indicating the predetermined binary value is arranged in parallel with the number of dots to be linked.
And the process of creating the cyclic dot number data
The division of the block is performed based on the character dot data.
Instead, perform the above-mentioned substitute character dot data.
And features.

The character dot data according to claim 5 of the present invention.
The data compression method is based on the effective
Invalid pixels corresponding to the pixel and the background pixel of the character.
The character is composed of a dot matrix composed of
For character dot data expressing
For dot, it said Yes when both are of different kinds of dots
Effective dots are assigned, and when both are of the same type,
By assigning invalid dots, the character dots
Create exclusive pixel dot data of the same size as the data.
A step of creating another pixel dot data;
Block that divides the data into blocks of predetermined multiple dots.
Block division process, and for each divided block,
When the effective dot is included in the block,
One of the two values is assigned, and the effective dot is included
If not, assign the other of the two specified values
In this way, the binary data indicating the predetermined binary is
Create the first compressed data arranged by the number of blocks
A first compressed data creation step, including the effective dot
For each block, the effective dot is the predetermined binary value.
And assigning the invalid dot to the
By assigning the other of the two fixed values,
The effective dot includes binary data indicating a predetermined binary value.
The second pressure lined up by the total number of dots in each block
A second compressed data creation step of creating compressed data.
Based on the first compressed data and the second compressed data
The character data obtained by compressing the character dot data
A method of compressing character dot data to be created,
Prior to creation of dot data for other pixels, the character dot data
By circulating the data in a predetermined direction, the effective
The number of blocks that include
Dot to create substitute character dot data
And the number of dots circulating in the predetermined direction
Circular dot for arranging binary data indicating predetermined binary
A number data creating step, wherein the exclusive pixel
Create the cut data instead of the character dot data.
The method is performed on the substitute character dot data.
And

The character dot data according to claim 6 of the present invention.
The data compression method is based on the effective
Invalid pixels corresponding to the pixel and the background pixel of the character.
The character is composed of a dot matrix composed of
For character dot data expressing
If the dots are different types of dots,
Effective dots are assigned, and when both are of the same type,
By assigning invalid dots, the character dots
Create exclusive pixel dot data of the same size as the data.
A step of creating another pixel dot data;
Block that divides the data into blocks of predetermined multiple dots.
Block division process, and for each divided block,
When the effective dot is included in the block,
One of the two values is assigned, and the effective dot is included
If not, assign the other of the two specified values
In this way, the binary data indicating the predetermined binary is
Create the first compressed data arranged by the number of blocks
A first compressed data creation step, including the effective dot
For each block, the effective dot is the predetermined binary value.
And assigning the invalid dot to the
By assigning the other of the two fixed values,
The effective dot includes binary data indicating a predetermined binary value.
The second pressure lined up by the total number of dots in each block
A second compressed data creation step of creating compressed data.
Based on the first compressed data and the second compressed data
The character data obtained by compressing the character dot data
A method of compressing character dot data to be created,
Represents each character including kanji, symbols, letters or numbers
Exclusive pixel dots created based on the character dot data
Dot pattern that appears in many of the
Is defined as one or more specific dot patterns,
Prior to the block division, the exclusive pixel dot data
The specific dot pattern that encodes the specific dot pattern
Create specific dot pattern data
Data creation step, and a code as the specific dot pattern data.
The specific dot pattern converted to the exclusive pixel dot.
From the default data to create the substitute exclusive pixel dot data.
A specific dot pattern deleting step to be performed,
The block division is performed in place of the exclusive pixel dot data.
Instead, it is performed on the substitute exclusive pixel dot data.
It is characterized by the following.

Also, the character dot data according to claims 1 to 6
In the data compression method, the predetermined binary values are 0 and 1.
And the binary data is bit data represented by 1 bit.
It is preferred that

Further , the character dot data according to claims 1 to 7 is provided.
In the data compression method, the effective dots are black dots.
Preferably, the invalid dots are white dots.

The character dot data according to claim 9 of the present invention.
The data compression device uses the effective dots corresponding to the pixels that make up the character.
Invalid pixels corresponding to the pixel and the background pixel of the character.
The character is composed of a dot matrix composed of
A predetermined number of character dot data
A block dividing means for dividing into blocks for each dot;
For each of the divided blocks,
When an effective dot is included, one of the predetermined two values
When the effective dot is not included,
By allocating the other of the predetermined two values,
The binary data indicating the predetermined binary is equivalent to the number of the blocks.
First compressed data creation for creating the first compressed data arranged side by side
Means, and for each block containing the effective dot,
The effective dot is one of the predetermined two values.
And assigns the invalid dot to the invalid dot,
By assigning the other, the predetermined binary value is indicated.
The binary data of each block containing the effective dots.
Creates the second compressed data arranged by the total number of dots of
Second compressed data creating means, and the first compressed data
Data based on the data and the second compressed data.
Character dot to create character data that is compressed data
A data compression device that handles kana, kanji, symbols,
Or a character dot data that represents each character
Dot patterns that appear in many of the
One or more specific dot patterns are defined, and
Prior to the division of the mark, it is included in the character dot data.
Specific dot pattern that codes specific dot pattern
Specific dot pattern data creation means for creating data
And encoded as the specific dot pattern data
The specified dot pattern from the character dot data
Specific dot pattern to create the substitute character dot data.
And turning off the block.
Replaces the character dot data with the substitute character
This is performed for target data.

The character dot data according to claim 10 of the present invention.
The data compression device has an effective
Invalid corresponding to the dot and the background pixel of the character
The sentence composed of a dot matrix composed of dots
Adjacent for character dot data expressing characters
For each dot, before when both of the disparate dots Symbol
Assign effective dots and when both are the same type of dots
By assigning the invalid dot, the character
Create exclusive pixel dot data of the same size as
Exclusive pixel dot data creating means, and the exclusive pixel dot
A block that divides data into predetermined blocks of a plurality of dots.
For the lock dividing means and each divided block,
When the effective dot is included in the block of
One of the two fixed values, and the effective dot
If not, the other of the two predetermined values is divided.
By attaching the binary data indicating the predetermined binary,
Create the first compressed data arranged by the number of the blocks.
First compressed data creating means, and the effective dots are included.
For each of the blocks,
Assigns one of the values to the invalid dot.
By allocating the other of the predetermined two values,
The binary data indicating the predetermined binary is expressed by the effective dot
The second lined up by the total number of dots of each block included
Second compressed data creating means for creating compressed data.
Based on the first compressed data and the second compressed data
The character data obtained by compressing the character dot data
A compression device for character dot data to be created,
Represents each character including kanji, symbols, letters or numbers
Common to many of the character dot data
Set one or more dot patterns as specific dot patterns
Prior to creation of the exclusive pixel dot data,
The specific dot pattern included in the character dot data is
Identification to create coded specific dot pattern data
Means for creating dot pattern data, the specific dot pattern
Specific dot pattern coded as pattern data
Is deleted from the character dot data, and the substitute character
Specific dot pattern deleting means for creating default data.
The apparatus further comprises: generating the exclusive pixel dot data,
Substitute character dot data instead of character dot data
Is performed for the target.

The character dot data according to claim 9 or 10 is also provided.
In the data compression device, the one or more specific dot patterns
Area with a predetermined dot width in the vertical or horizontal direction.
Includes a dot pattern that extends for a fixed dot length
Is preferred.

The character dot data according to claim 12 of the present invention.
The data compression device has an effective
Invalid corresponding to the dot and the background pixel of the character
The sentence composed of a dot matrix composed of dots
For character dot data expressing characters,
Block dividing means for dividing into blocks of several dots,
For each of the divided blocks,
When an effective dot is included, one of predetermined two values is used.
When the effective dot is not included,
By allocating the other of the predetermined two values,
The binary data indicating the predetermined binary is equivalent to the number of the blocks.
First compressed data creation to create first compressed data
Generating means and each block including the effective dots.
The effective dot is one of the predetermined two values.
And assigns the invalid dot to the invalid dot,
By assigning the other, the predetermined binary value is indicated.
The binary data of each block containing the effective dots.
Creates the second compressed data arranged by the total number of dots of
Second compressed data creating means, and the first compressed data
Data based on the data and the second compressed data.
Character dot to create character data that is compressed data
An apparatus for compressing data, the apparatus comprising:
That is, the character dot data is circulated in a predetermined direction.
By the above, the number of blocks containing the effective dots is
Substitute character dots to be reduced compared to character dot data
Dot circulating means for creating data, and circulating in the predetermined direction.
Binary data indicating the predetermined binary value is arranged in parallel with the number of dots to be linked.
And a means for creating cyclic dot number data that expresses all
The division of the block is performed based on the character dot data.
Instead, perform the above-mentioned substitute character dot data.
And features.

The character dot data of claim 13 of the present invention.
The data compression device has an effective
Invalid corresponding to the dot and the background pixel of the character
The sentence composed of a dot matrix composed of dots
Adjacent for character dot data expressing characters
For each dot, when both are different types of dots,
Assign effective dots and when both are the same type of dots
By assigning the invalid dot, the character
Create exclusive pixel dot data of the same size as
Exclusive pixel dot data creating means, and the exclusive pixel dot
A block that divides data into predetermined blocks of a plurality of dots.
For the lock dividing means and each divided block,
When the effective dot is included in the block of
One of the two fixed values, and the effective dot
If not, the other of the two predetermined values is divided.
By attaching the binary data indicating the predetermined binary,
Create the first compressed data arranged by the number of the blocks.
First compressed data creating means, and the effective dots are included.
For each of the blocks,
Assigns one of the values to the invalid dot.
By allocating the other of the predetermined two values,
The binary data indicating the predetermined binary is expressed by the effective dot
The second lined up by the total number of dots of each block included
Second compressed data creating means for creating compressed data.
Based on the first compressed data and the second compressed data
The character data obtained by compressing the character dot data
An apparatus for compressing character dot data to be created,
Prior to creation of dot data for other pixels, the character dot data
By circulating the data in a predetermined direction, the effective
The number of blocks that include
Dot to create substitute character dot data
Circulating means, the number of dots circulating in the predetermined direction
Circular dot for arranging binary data indicating predetermined binary
Number data creating means, wherein the exclusive pixel
Create the cut data instead of the character dot data.
The method is performed on the substitute character dot data.
And

According to a fourteenth aspect of the present invention, the character dot data
The data compression device has an effective
Invalid corresponding to the dot and the background pixel of the character
The sentence composed of a dot matrix composed of dots
Adjacent for character dot data expressing characters
For each dot, when both are different types of dots,
Assign effective dots and when both are the same type of dots
By assigning the invalid dot, the character
Create exclusive pixel dot data of the same size as
Exclusive pixel dot data creating means, and the exclusive pixel dot
A block that divides data into predetermined blocks of a plurality of dots.
For the lock dividing means and each divided block,
When the effective dot is included in the block of
One of the two fixed values, and the effective dot
If not, the other of the two predetermined values is divided.
By attaching the binary data indicating the predetermined binary,
Create the first compressed data arranged by the number of the blocks.
First compressed data creating means, and the effective dots are included.
For each of the blocks,
Assigns one of the values to the invalid dot.
By allocating the other of the predetermined two values,
The binary data indicating the predetermined binary is expressed by the effective dot
The second lined up by the total number of dots of each block included
Second compressed data creating means for creating compressed data.
Based on the first compressed data and the second compressed data
The character data obtained by compressing the character dot data
A compression device for character dot data to be created,
Represents each character including kanji, symbols, letters or numbers
Exclusive pixel dots created based on the character dot data
Dot pattern that appears in many of the
Is defined as one or more specific dot patterns,
Prior to the block division, the exclusive pixel dot data
The specific dot pattern that encodes the specific dot pattern
Create specific dot pattern data
Data creation means and a code as the specific dot pattern data.
The specific dot pattern converted to the exclusive pixel dot.
From the default data to create the substitute exclusive pixel dot data.
And a specific dot pattern deleting means to be formed.
The block division is performed in place of the exclusive pixel dot data.
Instead, it is performed on the substitute exclusive pixel dot data.
It is characterized by the following.

Further, the character dot data according to the ninth to fourteenth aspects is provided.
In the data compression device, the predetermined two values are 0 and 1.
And the binary data is a bit data represented by one bit.
Data.

Further, the character dot data according to claims 9 to 15 is provided.
In the data compression device, the effective dots are black dots.
Yes, the invalid dots are preferably white dots
No.

[0038]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
It will be described with reference to FIG. FIG. 5 is a flowchart used in the following description.

First, in storing character data for display or printing in a storage device in a microcomputer application device, if the original character data is represented by a dot matrix as in the above-described conventional compression method , Is divided into blocks each having several dots, and a block in which at least one dot is a black dot is provided with bit 1; a block in which all bits are 0 is provided with bit 0; by storing only the dot data of a given block as character data, you save the memory capacity of the character data in the storage device. Also,
Compression efficiency is improved by the aforementioned XOR step (S504)
Let it.

On the other hand, in the present embodiment,
In addition, (1) a process of coding and deleting a vertical image of a specific dot width that appears commonly in many kana-kanji characters, symbols, and alphanumeric characters ( hereinafter, "vertical image deletion process": 500); and (2) characters A step of sliding the whole data up and down by several dots ( hereinafter referred to as “dot slide step”: 501); and (3) encoding and deleting a character decoration part that appears in many kanji characters in a specific dot size or a specific typeface ( Hereinafter, “decoration information deletion step”: 503), the number of white blocks is reduced, and the character data is compressed.

Of these, (1) and (2) are XOR (S5
04) is pre-processing, and (3) is an XOR step (S50).
4) Post-processing. Since the characteristics of the dot pattern are different for each character, (1)
(2) All or any of the steps (3) may be omitted.

(1) Vertical Image Deletion Step FIG. 4 is a diagram in which character dot data is processed by the XOR step.

Here, as shown in the figure, since the horizontal image data is represented by the dots at both ends, it can be seen that the horizontal image data is greatly compressed. On the other hand, however, the vertical image data is left as black dots so that it can be clearly confirmed with the eyes, and it cannot be said that it has been compressed much yet. In this case,
As in the prior art described above, the horizontal
Although the XOR was performed, the vertical image data remained.
In the case of XOR between adjacent dots, the relationship is reversed.
(That is, horizontal image data is likely to remain.) Accordingly
In the following, the vertical or horizontal
"Vertical" will be described.

Therefore, in this step, a vertical image having a specific dot width is deleted from the original character dot data. The dot width is
The dot width that frequently appears in the dot size of the character,
In some situations, multiple dot widths can be targeted. The deleted vertical image data is coded using the X and Y coordinates and the length at the upper left of the start, and stored separately. FIG. 6 is a character dot pattern diagram after deleting a vertical image having a width of 2 dots. In FIG. 6, the vertical image information having a length of 16H is deleted from the coordinates (15H, 08H). An example in which the deleted vertical image information is stored in 2 bytes is shown in FIG. Thus, when the character is expanded, it can be uniquely decoded.

When the vertical image and the horizontal image intersect as shown in FIG. 8A, if the vertical image is deleted unilaterally as shown in FIG. 8C, the horizontal image data is increased from the conventional two end points to four end points by the XOR process as shown in FIG. 8C, so that the compression efficiency is reduced.
Therefore, in this case, a horizontal image is left as shown in FIG.
If you delete the dots of only the vertical image that does not cover the horizontal image, XO
After the R step, there are only two end points as shown in FIG.

As a result, when the XOR step is performed without performing this step, the number of white blocks is 58 as shown in FIG. 4, whereas when this step is performed, FIG.
It becomes a dot pattern like 0 (a), and the number of white blocks increases by 9 to 67. Further, in this example, since the number of deleted vertical images is three, the data amount used for vertical image information is 3 × 2 = 6 bytes. Therefore, the capacity of the character data is reduced by 67-58-6 = 3 (bytes).

(2) Dot Sliding Step FIG. 9A shows a row of dot data before the number character “3” is discriminated and decomposed. Already deleted some portraits,
It has gone through the EOR process. Here, as shown in (901) in the figure, when data spans a plurality of blocks, it can be predicted that the number of white blocks will increase if the way of taking blocks is shifted up and down. Therefore, conversely, the character dot data itself is slid up and down by several dots to increase the number of white blocks. How to take the block here, a column width of 1 dot, because it is a stage length of 8 dots, the same as the "vertical" of the above-mentioned
Slide up and down like this, but take the block horizontally
If it does, it will slide left and right. Therefore,
Then, slide in the predetermined direction of up and down (vertical) or
Slide up and down on behalf of the computer. Also, vertical slides of 8 dots or more can be equivalently converted to vertical slides of less than 8 dots. Further, the lower slide and the upper slide can be equivalently converted to each other. Therefore, in relation to the subsequent processing, here, all are represented by an upper slide of less than 8 dots.

FIG. 9B shows a dot pattern after the character dot data is slid up by three dots. As a result of the upper slide, the three rows overflowing from the top are directly added to the bottom (902). That is, as a result of the upper slide,
This means that the dots are circulated upward by three dots.

As a result, when the XOR step is performed without performing this step, the number of white blocks is 92, whereas
When this step is performed, the number of white blocks increases by eight, and
00 pieces. At the time of character pattern decoding, since the dot data must be slid downward, it is necessary to store slide information indicating how many dots should be slid in the memory. Since the slide amount is in the range of 1 to 7 dots, 3 bits are required for each piece of information. Therefore, in this example, the capacity of the character data is reduced by 100-92- (3/8) = 7.6 (bytes).

(3) Modification Information Deletion Step FIG. 10A shows an example of dot data before being discriminated and decomposed through a vertical image deletion step, a dot slide step, and an XOR step. The number of slide dots is 0. This is an example of kanji 32 dot data, and the font is Mincho. Here, the portion (A10) indicated by a circle in the figure is a pattern that frequently appears in this processing stage of many 32-dot Mincho Chinese characters other than this character. In this step, a specific pattern (from the original character dot data, which depends on the character modification pattern of the typeface, will be referred to as “character pattern” below) in order to increase the compression ratio by increasing the number of white dot blocks in the character dot data. Modification pattern ").

FIG. 10B shows the character dot pattern after the seven kinds of modification patterns are deleted.

The dot pattern of the decoration pattern itself is defined separately, and the decoration pattern is distinguished by assigning a code of about 5 bits. The decoration pattern data to be deleted is coded using the upper left X and Y coordinates and the pattern code, and stored separately. FIG. 11A shows FIG.
(A) It is the figure which extracted the modification pattern of A10. When a binary number 000001 is given as a pattern code to this decoration pattern, FIG.
01 has been deleted from the coordinates (1BH, 05H). FIG. 11B shows an example in which the deletion modification pattern information is stored in 2 bytes. With this, when the character is expanded, it can be uniquely decoded.

As a result, when the XOR step is performed without performing this step, the number of white blocks seen in FIG. 10A is 67, whereas when this step is performed, FIG.
As shown in (b), the number of white blocks is increased by 22 to 89. Further, in this example, since the number of deletion decorations is 7, the data amount used for the decoration information is 7 × 2 = 14 bytes.

In order to define the code of the decoration pattern, the memory must be allocated. However, when 32 kinds of decoration patterns are enumerated, a total of 160 bytes is required if 5 bytes are used for defining one decoration pattern. . Assuming that the total number of characters is Z, 160 / Z (bytes) per character causes an increase in character data as overhead.

Assuming that the total number of characters is 4000, in this example,
The capacity of character data is 89−67−14− (160/4000) = 7.96
(Bytes).

[0056]

According to the present invention, 32 dots.times.32 dots Mincho character data 4,7 commonly used in office electronic equipment.
The total original data amount of 41 characters is 128 (bytes) × 4741 (characters) = 606,848
(Bytes).

On the other hand, when compression is performed by the conventional "discriminating decomposition method", the total data amount is 319,791 (bytes).
become.

Therefore, the compression ratio is 319,791 / 606,848 = 52.7 (%)
It is.

On the other hand, when the compression according to the “discriminating decomposition method” is performed by actually utilizing the process according to the present invention, the total amount of data is 291,568 (bytes).

Accordingly, the compression ratio is 291,568 / 606,848 = 48.0 (%)
It is.

As described above, an improvement in the compression ratio of 4.7 points was realized.

In general, when storing character dot data in a storage device, the data capacity can be greatly reduced by using the method of the present invention.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a microcomputer application device according to an embodiment of the present invention.

FIG. 2 is a block diagram of a character dot pattern in a conventional method.

FIG. 3 is a diagram showing a compressed data amount of character dot data in a conventional method.

FIG. 4 is a diagram of a character dot pattern after an XOR step in a conventional method.

FIG. 5 is a flowchart of data compression in the embodiment.

FIG. 6 is a diagram illustrating a character dot pattern after a vertical image deletion step in the embodiment.

FIG. 7 is a diagram illustrating a storage example of deleted vertical image information in the embodiment.

FIG. 8A is a diagram of a character dot pattern before a vertical image deletion step in the embodiment. (B) It is a character dot pattern figure after the vertical image deletion process in an Example. (C) In an Example, it is a character dot pattern figure after an XOR process. (D) In an Example, it is a character dot pattern figure after the improved vertical image deletion process. (E) In an Example, it is a character dot pattern figure after the XOR process after the improved vertical image deletion process.

FIG. 9A is a diagram of a character dot pattern before a dot sliding step in the embodiment. (B) It is a character dot pattern figure after the dot slide process in an Example.

FIG. 10A is a diagram of a character dot pattern after an XOR step in the example. (B) It is a character dot pattern figure after the modification pattern deletion process in an Example.

FIG. 11A is a diagram showing an example of coding a decoration pattern in the embodiment. FIG. 14B is a diagram illustrating a storage example of deletion decoration information in the embodiment.

[Explanation of symbols]

 101: CPU 102: Built-in RAM 103: Gate Array 104: ROM, character dot data storage unit 105: RAM 106: Key input unit 107: Display unit 108: Printing unit 109: Power supply unit 500: Vertical image deletion process 501: Dot slide process 502: XOR process 503: Modification information process 504: Discrimination decomposition 901: 8-dot block 902 ... 3 rows of dot rows A01 ... Modification pattern

Continuation of the front page (56) References JP-A-1-159968 (JP, A) JP-A-62-153079 (JP, A) JP-A-60-176085 (JP, A) (58) Fields studied (Int .Cl. ⁷ , DB name) G09G 5/24 G06F 17/21 G06T 9/00

Claims (16)

(57) [Claims] An effective dot corresponding to a pixel constituting a character.
Invalid dots corresponding to the background pixels of the characters and the characters.
The character is composed of a dot matrix consisting of
Predetermined multiple dots for character dot data to be expressed
A block dividing step of dividing the data into blocks for each unit, and for each of the divided blocks,
When an effective dot is included, one of predetermined two values is used.
When the effective dot is not included,
By allocating the other of the predetermined two values,
The binary data indicating the predetermined binary is equivalent to the number of the blocks.
First compressed data creation to create first compressed data
Forming step, and for each block including the effective dot,
Assign one of the predetermined two values to the effective dot
The other of the predetermined two values is assigned to the invalid dot.
Is assigned, a binary data indicating the predetermined binary is assigned.
Data for each block containing the effective dots.
The second pressure for creating the second compressed data arranged by the total number of numbers
Comprising a reduced data producing step, a, based on the first compressed data and said second compressed data
Create character data by compressing the character dot data
Is a method of compressing character dot data, including characters that include kana, kanji, symbols, alphabetic or numeric characters.
Common to many of the character dot data
The appearing dot pattern is 1 as a specific dot pattern.
As described above, prior to the block division, the character dot data
Specific dots that encode the specific dot patterns included
Creating specific dot pattern data to create pattern data
And a special step coded as the specific dot pattern data.
Delete the fixed dot pattern from the character dot data
To create a substitute character dot data
Further comprising the step of:
In particular, the method is performed for the substitute character dot data.
Character dot data compression method. 2. An effective dot corresponding to a pixel constituting a character.
Invalid dots corresponding to the background pixels of the characters and the characters.
The character is composed of a dot matrix consisting of
For each character dot data to be represented,
When both are different types of dots,
Allocate dots, and when both are of the same type,
By assigning invalid dots, the character dot data
To create exclusive pixel dot data of the same size as the data
Pixel dot data creation process, The exclusive pixel dot data is stored in a block for each predetermined plurality of dots.
A block dividing step for dividing into locks; For each of the divided blocks,
When an effective dot is included, one of predetermined two values is used.
When the effective dot is not included,
By allocating the other of the predetermined two values,
The binary data indicating the predetermined binary is equivalent to the number of the blocks.
First compressed data creation to create first compressed data
Process, For each block containing the effective dots,
Assign one of the predetermined two values to the effective dot
The other of the predetermined two values is assigned to the invalid dot.
Is assigned, a binary data indicating the predetermined binary is assigned.
Data for each block containing the effective dots.
The second pressure for creating the second compressed data arranged by the total number of numbers
Compressed data creation process, With Based on the first compressed data and the second compressed data
Create character data by compressing the character dot data
Character dot data compression method, Each character of kana, kanji, symbol, letter including alphabet or number
Common to many of the character dot data
The appearing dot pattern is 1 as a specific dot pattern.
Has been determined above, Prior to creation of the exclusive pixel dot data, the character
Encodes a specific dot pattern included in the
Create a specific dot pattern data Putter
Data creation process, The characteristic coded as the specific dot pattern data
Delete the fixed dot pattern from the character dot data
To create a substitute character dot data
Removal process, Further comprising The creation of the exclusive pixel dot data is based on the character dot data.
Data instead of character data
A method of compressing character dot data. 3. The one or more specific dot patterns include:
Predetermined dot with specified dot width in specified vertical or horizontal direction
It is characterized in that it includes a dot pattern that is continuous only for a long length.
3. Compression of character dot data according to claim 1 or 2.
Method. 4. An effective dot corresponding to a pixel constituting a character.
Invalid dots corresponding to the background pixels of the characters and the characters.
The character is composed of a dot matrix consisting of
Predetermined multiple dots for character dot data to be expressed
A block dividing step of dividing into blocks for each unit; For each of the divided blocks,
When an effective dot is included, one of predetermined two values is used.
When the effective dot is not included,
By allocating the other of the predetermined two values,
The binary data indicating the predetermined binary is equivalent to the number of the blocks.
First compressed data creation to create first compressed data
Process, For each block containing the effective dots,
Assign one of the predetermined two values to the effective dot
The other of the predetermined two values is assigned to the invalid dot.
Is assigned, a binary data indicating the predetermined binary is assigned.
Data for each block containing the effective dots.
The second pressure for creating the second compressed data arranged by the total number of numbers
Compressed data creation process, With Based on the first compressed data and the second compressed data
Create character data by compressing the character dot data
Character dot data compression method, Prior to the block division, the character dot data is
Circulate in a predetermined direction In this way, the effective dots are included.
The number of included blocks is
Dot cycling to create substitute character dot data to reduce
Process and The number of dots circulating in the predetermined direction indicates the predetermined binary value.
Create cyclic dot count data to represent binary data side by side
Process and Further comprising The block division is performed in place of the character dot data.
In particular, the method is performed for the substitute character dot data.
Character dot data compression method. 5. An effective dot corresponding to a pixel constituting a character.
Invalid dots corresponding to the background pixels of the characters and the characters.
The character is composed of a dot matrix consisting of
For each character dot data to be represented,
When both are different types of dots,
Allocate dots, and when both are of the same type,
By assigning invalid dots, the character dot data
To create exclusive pixel dot data of the same size as the data
Pixel dot data creation process, The exclusive pixel dot data is stored in a block for each predetermined plurality of dots.
A block dividing step for dividing into locks; For each of the divided blocks,
When an effective dot is included, one of predetermined two values is used.
When the effective dot is not included,
By allocating the other of the predetermined two values,
The binary data indicating the predetermined binary is equivalent to the number of the blocks.
First compressed data creation to create first compressed data
Process, For each block containing the effective dot,
Assign one of the predetermined two values to the effective dot
The other of the predetermined two values is assigned to the invalid dot.
Is assigned, binary data indicating the predetermined binary value is assigned.
Data for each block containing the effective dots.
The second pressure for creating the second compressed data arranged by the total number of numbers
Compressed data creation process, With Based on the first compressed data and the second compressed data
Create character data by compressing the character dot data
Character dot data compression method, Prior to creation of the exclusive pixel dot data, the character
Data in a predetermined direction By circulating
The number of blocks containing effective dots is
Create substitute character dot data that is smaller than
Dot circulation process, The number of dots circulating in the predetermined direction indicates the predetermined binary value.
Create cyclic dot count data to represent binary data side by side
Process and Further comprising The creation of the exclusive pixel dot data is based on the character dot data.
Data instead of character data
A method of compressing character dot data. 6. An effective dot corresponding to a pixel constituting a character.
Invalid dots corresponding to the background pixels of the characters and the characters.
The character is composed of a dot matrix consisting of
For each character dot data to be represented,
When both are different types of dots,
Allocate dots, and when both are of the same type,
By assigning invalid dots, the character dot data
To create exclusive pixel dot data of the same size as the data
Pixel dot data creation process, The exclusive pixel dot data is stored in a block for each predetermined plurality of dots.
A block dividing step for dividing into locks; For each of the divided blocks,
When an effective dot is included, one of predetermined two values is used.
When the effective dot is not included,
By allocating the other of the predetermined two values,
The binary data indicating the predetermined binary is equivalent to the number of the blocks.
First compressed data creation to create first compressed data
Process, For each block containing the effective dot,
Assign one of the predetermined two values to the effective dot
The other of the predetermined two values is assigned to the invalid dot.
Is assigned, binary data indicating the predetermined binary value is assigned.
Data for each block containing the effective dots.
The second pressure for creating the second compressed data arranged by the total number of numbers
Compressed data creation process, With Based on the first compressed data and the second compressed data
The character dot Creates compressed character data
Character dot data compression method, Each character of kana, kanji, symbol, letter including alphabet or number
Created based on the character dot data that represents
Dots that commonly appear in many of the pixel dot data
Pattern is defined as one or more specific dot patterns.
Yes, Prior to the block division, the exclusive pixel dot data
The specific dot pattern that encodes the specific dot pattern
Create specific dot pattern data
Data creation process, The characteristic coded as the specific dot pattern data
The constant dot pattern is deleted from the exclusive pixel dot data.
Specific dot to create the substitute exclusive pixel dot data.
Pattern deletion process, Further comprising The block division is performed in place of the exclusive pixel dot data.
Instead, it is performed on the substitute exclusive pixel dot data.
A method of compressing character dot data. 7. The method according to claim 6, wherein the predetermined binary values are 0 and 1,
The binary data is bit data represented by one bit.
The method according to any one of claims 1 to 6, wherein
Compression method for character dot data. 8. The effective dot is a black dot.
The invalid dot is a white dot.
Compression of character dot data according to any of 1 to 7
Method. 9. An effective dot corresponding to a pixel constituting a character.
Invalid dots corresponding to the background pixels of the characters and the characters.
The character is composed of a dot matrix consisting of
Predetermined multiple dots for character dot data to be expressed
Block dividing means for dividing into blocks for each unit, For each of the divided blocks,
When an effective dot is included, one of predetermined two values is used.
When the effective dot is not included,
By allocating the other of the predetermined two values,
The binary data indicating the predetermined binary is equivalent to the number of the blocks.
First compressed data creation to create first compressed data
Means, For each block containing the effective dot,
Assign one of the predetermined two values to the effective dot
The other of the predetermined two values is assigned to the invalid dot.
Is assigned, binary data indicating the predetermined binary value is assigned.
Data for each block containing the effective dots.
The second pressure for creating the second compressed data arranged by the total number of numbers
Means for creating compressed data; With Based on the first compressed data and the second compressed data
Create character data by compressing the character dot data
Character dot data compression device, Each character of kana, kanji, symbol, letter including alphabet or number
Common to many of the character dot data
The appearing dot pattern is 1 as a specific dot pattern.
Has been determined above, Prior to the block division, the character dot data
Specific dots that encode the specific dot patterns included
Creating specific dot pattern data to create pattern data
Means, The characteristic coded as the specific dot pattern data
Delete the fixed dot pattern from the character dot data
To create a substitute character dot data
Means for deleting Further comprising The block division is performed in place of the character dot data.
In particular, the method is performed for the substitute character dot data.
Character dot data compression device. 10. An effective domain corresponding to a pixel constituting a character.
Invalid pixels corresponding to the pixel and the background pixel of the character.
The character is composed of a dot matrix composed of
For character dot data expressing
If the dots are different types of dots,
Effective dots are assigned, and when both are of the same type,
By assigning invalid dots, the character dots
Create exclusive pixel dot data of the same size as the data.
Other pixel dot data creation means, The exclusive pixel dot data is stored in a block for each predetermined plurality of dots.
Block dividing means for dividing into locks; For each of the divided blocks,
When an effective dot is included, one of predetermined two values is used.
When the effective dot is not included,
By allocating the other of the predetermined two values,
The binary data indicating the predetermined binary is equivalent to the number of the blocks.
First compressed data creation to create first compressed data
Means, For each block containing the effective dot,
Assign one of the predetermined two values to the effective dot
The other of the predetermined two values is assigned to the invalid dot.
Is assigned, binary data indicating the predetermined binary value is assigned.
Data for each block containing the effective dots.
The second pressure for creating the second compressed data arranged by the total number of numbers
Means for creating compressed data; With Based on the first compressed data and the second compressed data
Create character data by compressing the character dot data
Character dot data compression device, Each character of kana, kanji, symbol, letter including alphabet or number
Common to many of the character dot data
The appearing dot pattern is 1 as a specific dot pattern.
Has been determined above, Prior to creation of the exclusive pixel dot data, the character
Encodes a specific dot pattern included in the
Specific dot pattern to create specific dot pattern data
Data creation means, The characteristic coded as the specific dot pattern data
Delete the fixed dot pattern from the character dot data
To create a substitute character dot data
Means for deleting Further comprising The creation of the exclusive pixel dot data is based on the character dot data.
Data instead of character data
An apparatus for compressing character dot data. 11. The one or more specific dot patterns
Is a specified dot width and a specified dot width
It is characterized by including a dot pattern that continues only for
The character dot data according to claim 9 or 10,
Compression equipment. 12. An effective domain corresponding to a pixel constituting a character.
Invalid pixels corresponding to the pixel and the background pixel of the character.
The character is composed of a dot matrix composed of
A predetermined number of character dot data
Block dividing means for dividing into blocks for each dot, For each of the divided blocks,
When an effective dot is included, one of predetermined two values is used.
When the effective dot is not included,
By allocating the other of the predetermined two values,
The binary data indicating the predetermined binary is equivalent to the number of the blocks.
First compressed data creation to create first compressed data
Means, For each block containing the effective dot,
Assign one of the predetermined two values to the effective dot
The other of the predetermined two values is assigned to the invalid dot.
Is assigned, binary data indicating the predetermined binary value is assigned.
Data for each block containing the effective dots.
The second pressure for creating the second compressed data arranged by the total number of numbers
Means for creating compressed data; With Based on the first compressed data and the second compressed data
Create character data by compressing the character dot data
Character dot data compression device, Prior to the block division, the character dot data is
By circulating in a predetermined direction, the effective dots are included.
The number of included blocks is
Dot cycling to create substitute character dot data to reduce
Means, The number of dots circulating in the predetermined direction indicates the predetermined binary value.
Create cyclic dot count data to represent binary data side by side
Means, Further comprising The block division is performed in place of the character dot data.
In particular, the method is performed for the substitute character dot data.
Character dot data compression device. 13. An effective domain corresponding to a pixel constituting a character.
Invalid pixels corresponding to the pixel and the background pixel of the character.
The character is composed of a dot matrix composed of
For character dot data expressing
If the dots are different types of dots,
Effective dots, and both sides Before
By assigning invalid dots, the character dots
Create exclusive pixel dot data of the same size as the data.
Other pixel dot data creation means, The exclusive pixel dot data is stored in a block for each predetermined plurality of dots.
Block dividing means for dividing into locks; For each of the divided blocks,
When an effective dot is included, one of predetermined two values is used.
When the effective dot is not included,
By allocating the other of the predetermined two values,
The binary data indicating the predetermined binary is equivalent to the number of the blocks.
First compressed data creation to create first compressed data
Means, For each block containing the effective dot,
Assign one of the predetermined two values to the effective dot
The other of the predetermined two values is assigned to the invalid dot.
Is assigned, binary data indicating the predetermined binary value is assigned.
Data for each block containing the effective dots.
The second pressure for creating the second compressed data arranged by the total number of numbers
Means for creating compressed data; With Based on the first compressed data and the second compressed data
Create character data by compressing the character dot data
Character dot data compression device, Prior to creation of the exclusive pixel dot data, the character
By circulating the set data in a predetermined direction,
The number of blocks containing effective dots is
Create substitute character dot data that is smaller than
Dot circulation means, The number of dots circulating in the predetermined direction indicates the predetermined binary value.
Create cyclic dot count data to represent binary data side by side
Means, Further comprising The creation of the exclusive pixel dot data is based on the character dot data.
Data instead of character data
An apparatus for compressing character dot data. 14. An effective dot corresponding to a pixel constituting a character.
And the characters Invalid pixels corresponding to background pixels
The character is composed of a dot matrix composed of
For character dot data expressing
If the dots are different types of dots,
Effective dots are assigned, and when both are of the same type,
By assigning invalid dots, the character dots
Create exclusive pixel dot data of the same size as the data.
Other pixel dot data creation means, The exclusive pixel dot data is stored in a block for each predetermined plurality of dots.
Block dividing means for dividing into locks; For each of the divided blocks,
When an effective dot is included, one of predetermined two values is used.
When the effective dot is not included,
By allocating the other of the predetermined two values,
The binary data indicating the predetermined binary is equivalent to the number of the blocks.
First compressed data creation to create first compressed data
Means, For each block containing the effective dot,
Assign one of the predetermined two values to the effective dot
The other of the predetermined two values is assigned to the invalid dot.
Is assigned, binary data indicating the predetermined binary value is assigned.
Data for each block containing the effective dots.
The second pressure for creating the second compressed data arranged by the total number of numbers
Means for creating compressed data; With Based on the first compressed data and the second compressed data
Create character data by compressing the character dot data
Character dot data compression device, Each character of kana, kanji, symbol, letter including alphabet or number
Created based on the character dot data that represents
Dots that commonly appear in many of the pixel dot data
Pattern is defined as one or more specific dot patterns.
Yes, Prior to the block division, the exclusive pixel dot data
The specific dot pattern that encodes the specific dot pattern
Create specific dot pattern data
Data creation means, The characteristic coded as the specific dot pattern data
The constant dot pattern is deleted from the exclusive pixel dot data.
To create substitute exclusive pixel dot data Specific dock
Pattern deletion means; Further comprising The block division is performed in place of the exclusive pixel dot data.
Instead, it is performed on the substitute exclusive pixel dot data.
An apparatus for compressing character dot data. 15. The predetermined binary value is 0 and 1,
The binary data is bit data represented by one bit.
The method according to any one of claims 9 to 14, wherein
A device for compressing the described character dot data. 16. The effective dot is a black dot.
The invalid dot is a white dot.
Item 9 to 15
Compression device.