JPH0683309A - Character data compressing method and printing device - Google Patents

Abstract

PURPOSE:To store a small-capacity memory with outline data on many characters by compressing the outline data on the characters. CONSTITUTION:The outline of a Ming-style character is represented by position coordinate data on respective apexes and basic command data showing lines between the respective apexes are straight lines or curved lines. The outline data are structured by tracing the respective apexes of the continuous external and internal frames in order; and longitudinal and lateral lines, and straight and curved lines are repeated to form a specific outline shape, and a specific regular array is obtained at a partial part. In consideration of this regular array, extension commands corresponding to respective rules are prepared and used to compress the data by omitting data at the regular array parts. Consequently, outline data on plural fonts (e.g. Gothic style and Ming style) of respective non-Chinese-characters and characters of JIS 1st and 2nd standards can be compressed and stored in the small-capacity memory.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a character data compression method and a printing apparatus, and more particularly to a character data compression method and a printing apparatus suitable for compressing outline font character data (hereinafter referred to as contour data). Regarding

[0002]

2. Description of the Related Art In recent years, document creation apparatuses such as word processors and printers connected to them are required to have high-definition printing, and therefore, more and more have character data for printing as contour data. On the other hand, there is also a request to print characters of various shapes such as Mincho typeface and Gothic type in a mixed manner.
It also has both Gothic outline data.

Table 1 shows basic command data used to represent the contour data of each character. In this example, the basic commands are "start point", "single straight line", "single curve", "contour end", and "character end".

[0004]

[Table 1]

FIG. 5 shows the outline of the Mincho typeface of the character "tori". FIG. 8 is a configuration diagram of the contour data showing the contour using the basic command shown in Table 1 and each vertex coordinate. The basic command is 8-bit data in the example of Table 1, but the abbreviation is used in FIG. Hereinafter, abbreviations are enclosed in "".

In FIG. 8, the outline data of the Mincho body of "Tori" consists of data a, b, c, d, e, f and g. The data a is the outer contour of the partial "ear" of "Tori", and the vertex P0
0, P01 → P02 → ... → P0F → P0G → P0H (= P00) in this order. First, write the X and Y coordinate data of the start point P00 after the basic command data “80” indicating the “start point”, and then the line type connecting the start point P00 and the next vertex P01 is “single straight line”. The basic command data “81” indicating that it is “,” and the X and Y coordinate data of the vertex P01 are written. And so on. Since the line connecting the vertices P0A and P0D is a curve, the provisional vertices P0B and P0C are replaced by vertices P0A and P0A.
It is assumed to be on the tangent line at 0D, and the space between them is represented by Bezier curve data. Therefore, the basic command data “82” indicating “single curve” and the X and Y coordinate data of each vertex P0B, P0C, P0D are written. Below, write the contour data up to the vertex P0H,
Finally, basic command data "8" indicating "end of contour"
Write 3 "to end data a.

The data b is the outer contour of the "mata", which is the sword of "Tori", with the respective vertices P10 → P11 → P12 → ... → P1S → P1T → P1U → P1V (=
This is contour data that makes one round in the order of P10). This data b
Is also expressed by the data of a single straight line and a single curve. Data c
Is the inner contour of the closed region c of the "Mata" of "Tori".
This is contour data that makes one round in the order of P20 → P21 → ... → P26 → P27 (= P20). The data d, e, and f are contour data obtained by going around the inner contours of the three closed regions d, e, and f of the “ear” partial “ear” in order of each vertex, and as the last data g,
The basic command data "84" indicating "end of character" ends all contour data.

[0008]

A document creation device, printer, or the like uses about 8,000 characters such as JIS Kanji and non-Kanji of JIS level 1 and level 2 as character data for printing the created text. Have in memory. When each of these character data is provided as contour data, the amount of data per character becomes the amount of data shown in FIG. 8, and when two fonts of Mincho typeface and Gothic typeface are used, each character type The amount of data is about twice the amount of data in FIG. 8, and a large capacity memory is required. For example, when storing the contour data of two typefaces of Mincho typeface and Gothic type in the memory, a memory of 5 megabytes is required, which increases the manufacturing cost of the document creation device and the like, and is also disadvantageous in downsizing the entire device. There's a problem. This problem is further magnified when it becomes necessary to have contour data of other typefaces such as a writing brush or a round Gothic type, and it becomes a factor that hinders the popularization of high-performance document creation devices and the like.

It is an object of the present invention to provide a character data compression method and a printing apparatus capable of storing a large amount of character contour data in a small capacity memory.

[0010]

[Means for Solving the Problems] The above-mentioned object is to configure basic command data indicating "start point", "single straight line", "single curve", "contour end", and "character end", respectively, and character contours. In the method of compressing the contour data of a character represented by the coordinate data of each vertex, when the same basic command data is continuous in the contour data, the same continuous basic command data is expanded to indicate "continuation". This is achieved by replacing the command data with numerical data representing the number of consecutive commands and compressing the data amount.

The above object is also achieved by omitting the contour end command data added immediately before the start point command data and the contour end command data added immediately before the character end command data.

The above-mentioned object is also to use the extended command data indicating "quadrilateral" when the quadrilateral part is represented by the basic command data and each vertex coordinate data in the contour data. This is achieved by omitting the start point data and the contour end data in the data.

The above-mentioned object is also to provide extended command data indicating that all the vertices of the quadrangle are right angles instead of the basic command data when all the vertices of the quadrangle are right angles. This is achieved by representing the quadrilateral shape portion of the contour data with the X and Y coordinate data of the two diagonal vertices.

The above-mentioned object is also a method of compressing the character outline data represented by the coordinate data of each vertex of the outline when drawing the outline of the character and the command data indicating the function of the vertex, which is frequently used. This is achieved by expressing the contour data of a character that is less frequently used with the command data that is the same as the command data that represents the contour data of 1.

The above object is also achieved by replacing the basic command data with the extended command data indicating the repetition when the contour data has a repeating portion of a single curve → a straight line → a simple curve.

The above object is also achieved by using, when the contour data includes the same portion as a predetermined shape, extended command data indicating that the contour data portion indicating the shape is replaced with the shape. It

[0017]

In the character contour data, there are repeated portions. For example, in the data a in FIG. 8, ten basic command data “81” indicating “single straight line” are consecutive, followed by basic command data “82” of “single curve”, and then “ Four basic command data “81” of “single straight line” are continuous. By replacing the first “81” of 10 consecutive “81” s with the separately provided extended command data and indicating that 9 consecutive “81s” have been shown, 9 “81s” can be omitted, and the data amount corresponding to that is compressed. It

Further, in the contour data of FIG. 8, "contour end"
It can be seen that the command data “83” always comes immediately before the “start point” command data “80” and the “character end” command data “84”. Therefore, even if this "83" data is omitted, the existence of "contour end" can be naturally understood from the command data that follows it, so "83" can be omitted, and the data amount is compressed.

Comparing, for example, the vertex P01 and the vertex P02 in the contour of FIG. 5, it can be seen that only the Y coordinate data has changed without changing the X coordinate data of both. Also the apex
Comparing P06 and vertex P07, the Y coordinate data of both do not change, but only the X coordinate data changes. Therefore,
In the data of FIG. 8, P01x = P02x, and P06y = P07y.
Is. Therefore, it is possible to omit the data of P02x and P07y and compress the data amount.

For example, the data d in FIG. 8 is quadrilateral data. The contour data of the quadrilateral has coordinate data of the start point and coordinate data of the end point, but since the quadrangle is a closed figure, the start point and the end point are the same. Therefore, since the same data is included, it is possible to omit this and compress.

For example, the data e and f in FIG. 8 are quadrilateral data in which the four vertex angles are right angles, and the respective X and Y coordinate data of the four vertexes are described. However, if the four vertex angles are right angles, the shape can be known by knowing the X and Y coordinate data of the two diagonal points. Therefore, in the case of such a quadrangle, the X and Y coordinate data of the other two points can be omitted, and the data amount is compressed.

The basic command data is represented by 8-bit data, for example. However, if the basic command data that composes the character data of the second-level Kanji that is rarely used is also composed of 8 bits, the total amount of data becomes enormous. Therefore, even with the same command data, 8
It is possible to compress the amount of data by preparing the bit data and the 6-bit data, and expressing the basic command data used for the outline data of characters that are rarely used by the 6-bit data. Become.

In the contour of FIG. 5, the horizontal scale shape at the right end portion of the horizontal line of the first image of the "ear" is used in various characters as long as it is a Mincho type character. Therefore, data can be compressed by defining this shape as a template and using an extended command to instruct replacement with the template.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. Table 2 shows command data used in the embodiment of the present invention.
Shown in.

[0025]

[Table 2]

In addition to the conventional basic commands (Table 1), "quadrilateral", "quadrangle (4 vertex angles are 90 degrees)",
"Continuous line", "Line with continuous information", "Continuous curve",
Extended commands indicating "composite C-L-C", "composite C-L-C-L", "horizontal scale replacement 1, 2, 3", and "vertical scale replacement 1, 2, 3" are provided. As data representing each command, 8-bit data and 6-bit data are prepared, and 8-bit commands are used for the outline data of frequently used characters, and 6 lines are used for the outline data of infrequently used characters. A bit command is used to reduce the amount of data.

FIG. 4 is a contour data configuration diagram of "take" when the embodiment corresponding to claim 1 of the present invention is applied to the data shown in FIG. In the data a in the contour data shown in FIG. 8, the “single straight line” command data “81” is 10
The “single curve” command data “82” comes next, and then the “single straight line” command data “81” continues four times. In the present embodiment, the ten "81" sequences and four "81" sequences are data-compressed by using the "continuous straight line" command "A-" shown in Table 2.
In the "-" part, a continuous number (in the case of one, "0",
In the case of two, it is "1". ). Therefore, as shown in FIG. 4, the first 10 "81" sequences are "A".
It becomes 9 ", and the sequence of four" 81 "becomes" A3 ".
That is, it is possible to compress 12 "81" data in the data a, and thus the data amount of 12 bytes can be reduced.

In the data b of FIG. 8, there are three consecutive "single curve" commands "82". These continuations are shown in FIG. 4 using the “Continuous curve” command “E-” in Table 2.
As shown in, data compression is performed.

FIG. 3 is a "trial" when the embodiment corresponding to claim 3 of the present invention is further applied to the data shown in FIG.
It is a contour data configuration diagram of. Looking at the positional relationship between the vertices P01 and P02 in FIG. 5, the vertices P01 and P02 have the same X coordinate value and differ only in the Y coordinate value. Also, looking at the positional relationship between the vertices P04 and P05, the same Y coordinate value is taken and only the X coordinate value is different. The vertices P06 and P07 have the same Y coordinate value and differ only in the X coordinate value. Apex P07
And the vertex P08 take the same X coordinate value, and differ only in the Y coordinate value. The contour data of FIGS. 8 and 4 have all the X coordinate values and the Y coordinate values of each vertex in the data. The contour of a character is often followed by vertices having the same X coordinate value and then vertices having the same Y coordinate value. If all the X coordinate values and Y coordinate values of these vertices are included in the contour data However, the amount of data becomes large by itself. When taking the same coordinate value, for example, in the contour data indicated by the continuous straight line “A9” in FIG. 4, if the place where the same coordinate value is obtained is known, the latter data having the same continuous coordinate value is omitted. However, it is possible to know what the omitted coordinate value is. Therefore, in the present embodiment, as shown in FIG. 3, the continuous straight line "A9" is replaced with the "continuous straight line with continuous information" command "C" in Table 2.
The data is compressed by "-". Since the number of continuations is "9" as above, enter "C9". This continuous straight line "C"
With 9 ", as shown in FIG. 3, coordinate values" P02x "and" P05y "
"P07y" and "P08x" are omitted. The data indicating the positions of these coordinate values is represented as "F7 6E 0F". This determination method will be described with reference to FIG.

It is assumed that the vertex coordinates P01x is X1, P01y is Y1, P02x is X2, P01y is Y2 .... FIG. 6 shows the presence or absence of a change in the coordinate value of each vertex, with "1" when the coordinate value has changed and "0" when the coordinate value has not changed.
Looking at this as 4 hexadecimal data from the left, the first 4 bits are "7" and the next 4 bits are "F".
Becomes This is the first "F7" above. Similarly, it becomes "6E", and "0" of the last "0F" is added to match the number of bits. "F76E 0
F "is only displayed in hexadecimal, and when actually stored in the memory as contour data, this part is
It has as "111101110110111000001111". That is, 4
By omitting the coordinate data of one portion, the coordinate data of one portion is reduced by 8 bits × 4 = 32 bits, and since 24 bits are added, the data compression amount in this portion is 8 bits.

FIG. 2 is contour data of "take" when an embodiment corresponding to claim 5 of the present invention is further applied to the data of FIG. In FIG. 5, each vertex angle of the quadrilaterals f and e is a right angle. A quadrilateral whose four vertices are all right angles is uniquely determined by knowing the starting point position and the coordinates of the vertices diagonally opposite to the starting point. However, FIG.
In the contour data e of, the vertices P41, P42, P43 are next to the start point P40.
The coordinates of the three vertices of are written, and the same point as the starting point is set as P44 as the end point and its coordinates are also written. With respect to such data, extra data exists even in the data compression according to the embodiment up to FIG. Therefore, in this embodiment, an extended command “4-” indicating “quadrangle (corner of four sides is 90 degrees)” in Table 2 is provided, and when this command is used, coordinate data of two diagonal points of four vertices. Have only. The portion "-" is the number of repetitions, and in this embodiment, it is "1" because two rectangles f and e are continuous. As a result, the amount of data is further compressed.

FIG. 1 shows "take" contour data when the embodiment corresponding to claims 2, 4 and 7 of the present invention is further applied to the data of FIG. In the data shown in FIG. 2, there is "83" indicating the end of the contour. However, there is a rule that the start point (including data similar to the start point. For example, the abbreviation “41” indicating the square e may also include the start point) or the character end is followed by the end of the contour. Therefore, the data is duplicated. Therefore,
Even if "83" is omitted, it is possible to reliably predict the omitted contour end from the start point or the character end.

Next, regarding the data of the quadrangle d shown in FIG. 5, in FIG. 2, P31, P32, P33, P34 next to the starting point P30.
Data compression is performed on the coordinate data of (= P30) by the method described in FIG. However, since the last vertex P34 is the same as the starting point P30, there is duplication of data, and if the data compression method in FIG. 6 is performed from the starting point P30,
Further, the data can be compressed. Therefore, in this embodiment, by using the "quadrilateral" extension command "8A" in Table 2, it is shown that this data portion is a quadrilateral, and this data compression is performed.

When the contours of various characters are analyzed, the single curve "82" is followed by the single straight line "81", and then the single curve "82" again appears frequently. Furthermore, there is a high frequency that a single straight line “81” will come next. Therefore, in this embodiment, as shown in Table 2, "composite" extension commands "01" and "02" are provided, and when there is a repeated portion of such a line, the extension command is used to set "8".
1 "and" 82 "are omitted. According to the data of FIG.
It can be seen that the portion 2-81-82 exists in the data b. Therefore, the command data of that part is made into this composite command. In Fig. 1, the command of the relevant part is "01".
I am trying. Since various data compression methods are applied in the example of FIG. 1, when "01" is used, the command data before and after that is changed.

FIG. 7 is contour data of "take" when the embodiment corresponding to claim 8 of the present invention is applied to the data shown in FIG. In the case of Mincho, a scale-like shape is added to the end of the horizontal line or the end of the vertical line. There are not many types of this scale shape. Therefore, in the present embodiment, the data indicating the scale shape is used as a template, and the data of the corresponding portion is replaced with this template data to compress the data. As an extended command indicating the replacement of this data, in the present embodiment, as shown in Table 2, three types of horizontal scale replacement and three types of vertical scale replacement are provided. When prepared, each extended command will be prepared. In FIG. 5, the shape of the vertices P01 → P02 → P03 → P04, which is the horizontal end portion of the first image of the biased “ears”, becomes a horizontal scale. Therefore, as shown in FIG. 7, the vertex coordinate data of this portion is replaced with the horizontal scale replacement command data “05” indicating this shape. As a result, a total of 40 bits of the five coordinate position data are replaced with 8-bit data indicating "05" (6 bits when the 6-bit system is used),
The amount of data is compressed.

When all the above-mentioned embodiments are applied,
A 2-megabyte memory is required to store the contour data of each character in Gothic font and Mincho font and non-Kanji characters. If the data shown in FIG. 8 has the outline data of these characters, it is compared with the need of 5 megabytes.
The memory amount is 40%, so that it is possible to realize high functionality of the document creation device and the like at low cost, and also contribute to reduction in size and weight of the document creation device and the like.

FIG. 9 is a block diagram of a printing apparatus connected to the document creating apparatus by a cable. The printing apparatus 1 is connected to the document creating apparatus 2 by a cable 8 and receives a print command and print data sent from the document creating apparatus 2 and a data receiving section 3 and performs control related to printing in accordance with the print instruction. It comprises a control unit 4, a printing unit 5 having a print head (not shown), and a storage device 7 having a character data memory 6 such as a ROM. Character data of a plurality of fonts compressed by the above-described compression method is stored in the memory 6, and the character data corresponding to the character code sent from the document creation device 2 as the printing data is read by the control unit 4. The paper is taken out, sent to the printing unit 5, and printed on paper. The memory 6 of the printing apparatus 1 has an effect of requiring a small capacity.

[0038]

According to the present invention, a large amount of character data can be compressed, and the outline data of various characters can be stored in a small capacity memory.

[Brief description of drawings]

FIG. 1 is a configuration diagram of compressed contour data of a Mincho character “Tori”.

FIG. 2 is a configuration diagram of compressed outline data of a Mincho typeface character “tori”.

FIG. 3 is a configuration diagram of compressed contour data of a Mincho typeface character “tori”.

FIG. 4 is a configuration diagram of compressed contour data of a Mincho typeface character “tori”.

FIG. 5 is a contour diagram of a Mincho typeface character “tori”.

FIG. 6 is an explanatory diagram of creating compressed data.

FIG. 7 is a configuration diagram of compressed contour data of a Mincho typeface character “tori”.

FIG. 8 is a configuration diagram of uncompressed contour data of the Mincho script “Tori”.

FIG. 9 is a configuration diagram of a printing apparatus.

[Explanation of symbols]

a ... Outer data of "Tori" biased "ear", b ... Outer data of "Tori""Mata", c ... Inverted triangle data in "Mata", d ... In "ear" The square data at the bottom of e, e ...
Square data in the middle of "ear", f ... Top square data in "ear", 1 ... Printing device, 2 ... Document creating device, 3 ... Data receiving unit, 4 ... Control unit, 5 ... Printing part,
6 ... Character data memory.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location B41J 5/44 8703-2C G06F 3/12 H 15/66 400 8420-5L (72) Inventor Standing Shozo 8-2, Kita 9 East, Higashi-ku, Sapporo City, Hokkaido Harima Co., Ltd.

Claims (9)

[Claims] 1. A "starting point", a "single straight line", a "single curve",
In the method of compressing the contour data of a character represented by the basic command data indicating "contour end" and "end character" and the coordinate data of each vertex forming the contour of the character, the same basic command is included in the contour data. When the data is continuous,
A character data compression method characterized in that the same continuous basic command data is replaced with extended command data indicating "continuation" and numerical data indicating the number of continuations to compress the data amount. 2. A "starting point", a "single line", a "single curve",
In the method of compressing character contour data represented by command data indicating "contour end" and "character end" respectively, and coordinate data of each vertex forming the character contour, the method is added immediately before the start point command data. A method for compressing character data, characterized in that the amount of data is compressed by omitting the contour end command data to be generated and the contour end command data added immediately before the character end command data. 3. A "starting point", a "single line", a "single curve",
A method for compressing character contour data represented by basic command data indicating "contour end" and "character end", respectively, and X and Y coordinate data of vertices forming the contour of the character. When the X coordinate data or the Y coordinate data of consecutive vertices is the same, the coordinate data after the consecutive coordinate data is omitted, and the basic command data attached to the coordinate data is omitted as described above. A method for compressing character data, characterized in that the amount of data is compressed by replacing it with extended command data indicating. 4. A "starting point", a "single straight line", a "single curve",
In the method of compressing the contour data of a character represented by the basic command data indicating "contour end" and "end character" and the X and Y coordinate data of each vertex forming the contour of the character, When the quadrilateral is represented by the basic command data and each vertex coordinate data, extended command data indicating "quadrilateral" is used to omit the start point data and the contour end data in the contour data of the quadrangle. A character data compression method characterized in that 5. A “starting point”, a “single straight line”, a “single curve”,
In the method of compressing the contour data of a character represented by the basic command data indicating "contour end" and "end character" and the X and Y coordinate data of each vertex forming the contour of the character, When the quadrilateral is represented by basic command data and each vertex coordinate data, and each vertex of the quadrilateral is a right angle, extended command data indicating that each vertex of the quadrilateral is a right angle. And a character data compression method, wherein the quadrilateral shape portion is represented by X and Y coordinate data of two diagonal vertices. 6. A method of compressing character contour data represented by coordinate data of each vertex of a contour when drawing a contour of a character and command data indicating a function of the vertex, the contour data of a character frequently used. A character data compression method characterized in that contour data of a character that is less frequently used is represented by command data that is the same as the command data that represents, but has a reduced number of bits. 7. A "starting point", a "single line", a "single curve",
In the method of compressing the contour data of a character represented by the basic command data indicating "contour end" and "end character" and the X and Y coordinate data of each vertex forming the contour of the character, A character data compression method characterized in that, when there is a repeating portion of a single curve → a straight line → a single curve, the basic command data is replaced with extended command data indicating the repetition. 8. A "starting point", a "single line", a "single curve",
In the method of compressing the contour data of a character represented by the basic command data indicating "contour end" and "end character" and the X and Y coordinate data of each vertex forming the contour of the character, A character data compression method characterized in that, when a portion having the same shape as a predetermined shape is included, the contour data portion indicating the shape is used as extended command data indicating that the shape has been replaced with the shape. 9. A memory storing at least character data compressed by the character data compression method according to claim 1, and character data read from the memory is printed on a print target. A printing device comprising: