KR19990023726A - Grayscale shared data generating device, Grayscale shared data restoring device, Grayscale data processing device, Grayscale shared data generating method, Grayscale shared data restoring method, Grayscale data processing method and computer readable recording medium - Google Patents

Abstract

The gradation sharing data generating apparatus shares plural kinds of gradation data for representing a symbol in accordance with a predetermined number of pixels indicating gradation from contour information representing the outline of a symbol including a character or a figure, and generates gradation sharing data. A gradation shared data generating device comprising: an outline information expansion and contraction unit (102), a basic gradation value calculation unit (103), and a generated gradation number for generating gradation data of gradation number 2 and gradation data of gradation number 3 from contour information; A gradation shared data generation unit 105 for generating gradation shared data of gradation number 4 from gradation data of 2 and gradation data of gradation number 3 is provided.

The gradation shared data restoring apparatus is a gradation shared data restoring apparatus for restoring gradation data from the gradation sharing data, and includes a gradation number selector 108 for selecting gradation number 2 or gradation number 3, and selecting from the gradation sharing data. Therefore, the first gray scale data restoration unit 109 restores the gray scale data of the gray scale number 2, and the second gray data restoration unit 110 restores the gray scale data of the gray scale number 3.

Description

Grayscale shared data generating device, grayscale shared data restoring device, grayscale data processing device, grayscale shared data generating method, grayscale shared data restoring method, grayscale data processing method and computer readable recording medium

According to the present invention, a gradation sharing data generation device for generating gradation sharing data for sharing plural kinds of gradation data representing a character or a figure using gradation, and gradation sharing for selecting gradation numbers and restoring gradation data from the generated gradation sharing data. The present invention relates to a data recovery apparatus.

Background Art In recent years, display quality, such as TV, portable information equipment, and digital satellite broadcasting receiving terminal, including CRTs of personal computers, has increased in importance.

In general, display devices such as CRTs of TVs and personal computers have lower resolutions than printers, and therefore, when the outlines of images and characters are jagged or cannot be expressed in detail, display quality is lower than in printed materials. In the display device, in order to compensate for this, to improve the resolution of the appearance and to approximate the quality of the printed matter, intermediate colors of these colors other than the foreground color and the background color are used to express the gradation of each pixel.

In the gradation data, the display quality is improved as the number of gradations available for one pixel increases, but the number of gradations that can be actually used is determined by the display capability of the display device.

Particularly in a system in which data representing text is transmitted and received by a communication line or a broadcast, when the device for generating gray data and the device using gray data are different from each other are limited to the number of colors that can be displayed simultaneously on the display device side. In a place where the number of tones that can be used (assigned for characters) differs depending on the display content, it is impossible to uniquely determine how many tones of data should be prepared in advance by the apparatus for transmitting the data. . For example, in such a data transmission / reception system, when the multimedia content is distributed and reproduced by a plurality of types of terminal apparatuses, when the number or type of data to be displayed by the terminal apparatuses is different, the transmitting apparatus side is used. You cannot decide in advance which halftone to use.

Conventionally, even in such a place, when the terminal apparatus has a multi-gradation display capability such as 65536 colors, such as a personal computer, a constant display quality is obtained by approximating and displaying the data of the maximum number of gray scales included in the terminal apparatus. In addition, when the terminal apparatus has a display capability of using a color palette of 256 colors, the minimum display quality is secured by assigning and displaying intermediate colors among the palettes not being used.

1 is a block diagram showing the configuration of a gradation shared data processing system of a first conventional example. The gradation shared data processing system of this first conventional example includes a gradation shared data generating apparatus (corresponding to the terminal apparatus described above) and a gradation shared data restoration apparatus. Here, for convenience of explanation, it is assumed that which of the two tone data, the two tone data and the three tone data, will be used as the tone share data restoration device, but is not specified in advance on the tone share data restoration device. The same applies to the same.

The gradation sharing data generating apparatus of the gradation sharing data processing system of the first conventional example includes an outline information holding unit 201, an outline information expanding and contracting unit 202, a two gradation data generating unit 203, and a three gradation data generating unit 304. And a gradation shared data generation unit 205. The gradation shared data restoring apparatus includes a gradation shared data extracting unit 206, a gradation number selection unit 207, a two gradation data restoring unit 208, and a three gradation data restoring unit 209.

In the two-gradation data, the gray scale used for each pixel is set to two colors of the foreground color and the background color. Here, a gray scale value of 1 is assigned to the foreground color and 0 to the background color. In two tone data, a tone value of one pixel can be expressed by one bit.

In the three-gradation data, the gradation used for each pixel is three colors of the foreground color, the middle color, and the background color. Here, two gradation values are assigned to the foreground color, one to the middle color, and zero to the background color. For the three-gradation data, the gray-scale value of one pixel can be represented by two bits.

The gray scale shared data is a combination of three gray scale data followed by two gray scale data.

As such a gradation shared data generating apparatus, the processing procedure from the outline data showing the outline of a character or a figure to the generation of the gradation shared data will be described first as (Process 1) to (Process 5).

(Process 1) First, the outline information holding unit 201 draws out and holds outline information on the requested character from a storage unit storing outline data. Here, it is assumed that outline information as shown in the following is drawn out and held.

2 (a) and 2 (b) are diagrams showing an example of outline information included in outline data representing characters, figures, and the like. The outline information here represents the Gothic alphabet "A" as a set of straight lines on a coordinate of 1000x1000 (hereinafter referred to as 1000 mesh). (Outline data has outline information of each character along with data such as font name, mesh number, etc. for a plurality of characters having integration such as alphabet or Chinese character).

The outline information of "A" is composed of coordinate points as shown in Fig. 2B showing two outlines, and the outline can be drawn by connecting each coordinate point in order (( Contour 1 can be drawn by connecting 125, 75), (450, 925), ..., (225, 75) in sequence, and (375, 450), (625, 450), (500, 8O0) Contour 2 can be drawn by linking them in order). Here, the end point coordinates and the start coordinates of the contour are automatically connected, and a quadratic curve or a cubic curve can be used together with a straight line.

(Process 2) Next, the outline information enlargement and reduction unit 202 enlarges and reduces the outline information held by the outline information holding unit 201 by the required number of pixels by (Process 1). Here, the contour information is reduced to 10 pixels in width and 10 pixels in height (pixels are used in the same sense as pixels).

In general, when 10 × 10 pixels (10 pixels in width and 10 pixels in height) are required, the outline information of 1000 mesh may be reduced to 10 mesh. However, to generate the gray scale data, it is necessary to determine the gray scale value for each pixel. have. Therefore, one pixel is divided into finer subpixels, the contour information is reduced in correspondence with the subpixels, and the gradation value is determined according to the number of subpixels included in the contour (including the contour image) among the one pixel. Determine.

For example, if one pixel is subdivided into 4 widths and 4 heights, one pixel is subdivided into 4x4 = 16 subpixels. Hereinafter, a mesh that subdivides one pixel is referred to as a "sub mesh", a boundary between pixels and pixels is referred to as a "pixel boundary", and a boundary between sub pixels and sub pixels is referred to as a "sub pixel boundary".

FIG. 3 is a diagram showing 10 × 10 pixels divided into 16 subpixels per pixel to generate grayscale data, and FIGS. 4A and 4B are shown in FIGS. It is a figure which shows the data after reducing the outline information shown.

In FIG. 3, a thick line represents a pixel boundary and a thin line represents a subpixel boundary. When the outline information represented by 1000 mesh is reduced to 10x10 pixels, the outline information is reduced to 40x40 subpixels, and a gray scale value is determined according to the number of subpixels included in the outline among one pixel.

The outline information expansion and contraction unit 202 (see FIG. 1) sets each coordinate value representing the outline information of "A" shown in FIG. 2B to 40/1000 times. 4 (a) and 4 (b) show the result of the reduced outline information in this way. The coordinate value obtained in this way takes a value in subpixel units.

(Process 3) The two-tone data generation unit 203 generates three-tone data by calculating the tone value of each pixel from the data shown in Fig. 4B generated by the outline information expansion and reduction unit 202.

Specifically, for each pixel, the number of subpixels included in the outline composed of the contour information after the enlargement and reduction generated by the outline information enlargement / reduction unit 202 is obtained, and the number of the subpixels constitutes one pixel. If it is equal to or greater than a certain ratio among all the sub-pixels, the foreground color, i.e., 1, is set. Here, out of 16 sub-pixels constituting one pixel, if S or more sub-pixels are included in the outline, the grayscale value of the pixel is included. If less than 8 sub-pixels are included in the outline, the pixel The gradation value is set to zero. FIG. 5 shows two tone data for " A " generated by the two tone data generation unit 203 in the above-described order.

(Process 4) The three gradation data generation unit 204 (see Fig. 1) calculates the gradation value of each pixel from the data shown in Fig. 4B generated by the outline information expansion and contraction unit 2402, and then executes the three gradation values. Generate data.

Specifically, as in (Process 3) described above, according to the number of sub-pixels included in the outline in one pixel, the gray level value of the pixel is either the foreground color, that is, 2, the middle color, that is, 1, the background color, that is, 0. Is assigned to. In this case, if 11 or more subpixels of the 16 subpixels constituting one pixel are included in the contour, the gray level value of the pixel is 2, 5 or more, and less than 11 subpixels are included in the contour. If less than one or five subpixels are included in the outline of the pixel, the gray level of the pixel is set to O. FIG. 6 shows three tone data for " A " generated by the three tone data generator 204 in the above-described order.

(Process 5) Next, the gradation shared data generation unit 205 (refer to FIG. 1) includes two gradation data generated by the two gradation data generation unit 203 and three generated by the three gradation data generation unit 204. Grayscale shared data is generated from grayscale data. Here, two tone data is concatenated with three tone data. FIG. 7 is a diagram showing gradation sharing data generated by the gradation sharing data generating unit 205 in this manner.

In the gradation shared data generating device, gradation shared data is generated from the outline data by the processes in (process 1) to (process 5) as described above.

Subsequently, the processing steps for restoring the grayscale shared data generated by the grayscale shared data generating apparatus with the grayscale shared data restoring apparatus in the same manner are described in (Process 6), (Process 7), (Process 8-1), ( Processing 8-2) will be described.

(Process 6) The grayscale shared data extracting unit 206 (see FIG. 1) extracts the grayscale shared data generated by the grayscale shared data generating apparatus.

(Process 7) The gradation number selection unit 207 starts the two-gradation data restoration unit 208 if the requested gradation number is two gradations, and the three gradation data restoration unit 209 if the requested gradation number is three gradations. (Either of (Process 8-1) and (Process 8-2) shown below are selected depending on whether the requested number of gradations is 2 or 3 gradations).

(Process 8-1) If the requested number of tones is 2 tones, the 3rd gradation data restoring unit 208 performs the 2 gradation data portion from the gradation sharing data extracted by the gradation sharing data extracting unit 206 (the gradation sharing data shown in Fig. 7). First half). As a result of this extraction, the two-gradation data shown in FIG. 5 (similar to the two-gradation data generated by the gradation shared data generating device) can be obtained.

(Process 8-2) If the requested gradation number is three gradations, the three gradation data restoration unit 209 uses the three gradation data portions (gradation sharing data shown in Fig. 7) from the gradation sharing data extracted by the gradation sharing data extracting unit 206. Extract the second half). As a result of this extraction, the three gradation data shown in FIG. 6 (similar to the three gradation data generated by the gradation shared data generating device) can be obtained.

When instructed when necessary, a character is displayed on the display unit based on either of the two-tone data and the three-tone data thus obtained.

In the gradation sharing data processing system of the first conventional example as described above, the amount of gradation sharing data generated is increased compared to the amount of 2-gradation data or 3-gradation data. In order to prevent such an increase in the amount of data, only the higher order data is generated, and when the data of the lower order is requested from the restoring device, the number of tones is converted by extracting or dithering. Techniques are generally used.

Fig. 8 is a block diagram showing the configuration of the gradation shared data processing system of the second conventional example using this method. The grayscale shared data processing system of this second conventional example includes two grayscale data, two grayscale data and three grayscale data, including a grayscale shared data generating device and a grayscale shared data restoring device, similarly to the grayscale shared data processing system of the first conventional example. It is assumed that the gradation value for the gradation which is the same as the gradation shared data processing system of the first conventional example is assigned to the two gradation data and the three gradation data.

The gradation sharing data generating apparatus of the gradation sharing data processing system of the second conventional example includes an outline information holding unit 301, an outline information expanding and contracting unit 302, and a high-order gradation data generating unit 303. The gradation shared data restoring apparatus includes a higher gradation data extracting unit 304, a gradation number selection unit 305, a lower gradation data restoring unit 306, and a higher gradation data restoring unit 307.

As such a gradation shared data generating apparatus, the processing procedure from the outline data to the generation of higher gradation data will be described first as (process 1) to (process 3).

(Process 1) First, the outline information holding unit 301 (see Fig. 8) extracts and holds the outline information of the requested outline data from the storage unit storing the outline data (here, the held outline information is shown in Fig. 2). Same as shown in (b) of FIG.

(Process 2) Next, the outline information enlargement and reduction unit 302 enlarges and reduces the outline information held by the outline information holding unit 301 by the process (1) to the required number of pixels. Here, similarly to the tone sharing data processing system of the first conventional example, tone sharing data composed of 10 pixels in width and 10 pixels in height is generated from the outline data. The data generated by the outline information expansion and contraction unit 302 is the same as that shown in FIG.

(Process 3) Subsequently, the higher gradation data generating unit 303 uses each of the gradation data generation systems of the first conventional example from the data shown in FIG. Three tone data are generated by calculating the tone value of the pixel. The resulting three-gradation data is the same as that shown in FIG.

As described above, by the processing in (Process 1) to (Process 3), the high level gray scale data (three gray scales indicate higher order than two gray scales) is generated in the gray scale shared data generating apparatus.

Next, the processing sequence for restoring the high-level grayscale data (gradation shared data) generated by the grayscale shared data generating device by using the grayscale shared data restoration device in this way is shown in (Process 4), (Process 5), (Process 6-). 1) and (Process 6-2).

(Process 4) The higher gradation data extracting unit 304 (see Fig. 8) extracts the higher gradation data (three gradation data) generated by the gradation sharing data generating apparatus.

(Process 5) The gradation number selection section 305 activates the lower gradation data restoration section 306 if the requested gradation count is three gradations, and activates the higher gradation data restoration section 307 if the requested gradation count is three gradations. Depending on whether the number of gradations is 2 or 3 gradations, any of (Process 6-1) and (Process 6-2) shown below is selected).

(Process 6-1) If the requested number of gradations is two gradations, the low gradation data restoration section 306 generates two gradation data from the three gradation data extracted by the higher gradation data extraction section 304.

Specifically, the higher-order gray value calculated for each pixel is taken out and converted to a lower-order gray value by performing some extraction process.

Here, when the gray level value of the extracted three-tone data is 0, the gray level value of the two-tone data is set to 0. If the gray level value of the extracted three-tone data is 1 or 2, the gray level value of the two-tone data is set to 1. FIG. 9A is a diagram showing three gradation data reconstructed from three gradation data for " A " by performing the above-described processing on all pixels.

If the gradation value of the 3 gradation data retrieved here is 0 or 1, the gradation value of the 2 gradation data is 1 and the gradation value of the 2 gradation data is 1 if the gradation value of the 3 gradation data is 2 . FIG. 9B is a diagram showing three gradation data reconstructed from three gradation data for " A " by performing the above-described processing on all pixels.

(Process 6-2) If the requested gradation number is three gradations, the higher gradation data retrieval unit 307 outputs the three gradation data extracted by the higher gradation data extracting unit 304 as it is. The three-tone data for "A" generated in this way is the same as that shown in FIG.

When necessary, if indicated, a character is displayed on the display unit based on either of the two-tone data and the three-tone data obtained in this manner.

By the way, according to the gradation shared data restoration apparatus of the gradation shared data processing system of the second conventional example, the two gradation data (refer to (a) and (b) of FIG. 9) to be restored is the two gradation data to be originally restored shown in FIG. Compared with that, the quality is considerably deteriorated.

As described above, the grayscale shared data processing system of the first conventional example has a problem in that the data amount is significantly increased as compared with the case of generating only two grayscale data or only three grayscale data with respect to the generated grayscale shared data. As a result, the amount of data in the storage unit for preserving the grayscale shared data increases, thereby increasing the price of the entire apparatus.In addition, when the data is transmitted / received using a communication line or broadcast, the amount of communication data increases, resulting in a decrease in processing performance. do.

On the other hand, in the grayscale shared data processing system of the second conventional example, the amount of data for the grayscale shared data generated is the same as that of the high-level grayscale data, but the quality deterioration of the low-level grayscale data is reduced by the conversion of the number of grayscale data from the high-order grayscale data to the low-order grayscale data. There is a problem that occurs. Examples of the grayscale data include image data, font data, and the like. In particular, in the case of generating grayscale data having a complex shape such as font data, deterioration of the quality due to the above conversion greatly affects the low-level grayscale data. It may become impossible to read the character represented by this.

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem, and an object thereof is to provide a gradation for sharing plural kinds of gradation data composed of different (maximum) gradations without increasing the amount of data and without causing deterioration of the restored data. There is provided a gradation shared data generating apparatus for generating shared data and a gradation shared data restoration apparatus capable of restoring gradation data from the gradation shared data. Another object of the present invention is to provide a gradation data processing apparatus for expressing characters and figures by using gradation with higher quality.

1 is a block diagram showing the configuration of a gradation shared data processing system of a first conventional example;

2 (a) and 2 (b) are diagrams showing an example of outline information included in outline data representing characters, figures, and the like.

FIG. 3 shows 10 × 10 pixels divided into 16 subpixels per pixel to generate grayscale data

4 (a) and 4 (b) show data after reduction of the contour information shown in FIGS. 2 (a) and 2 (b).

FIG. 5 shows two tone data of " A " generated by the two tone data generator 203. FIG.

FIG. 6 shows three tone data for " A " generated by the three tone data generator 204. FIG.

FIG. 7 is a diagram illustrating gradation sharing data generated by the gradation sharing data generating unit 205.

8 is a block diagram showing a configuration of a gradation shared data processing system of a second conventional example;

9 (a) and 9 (b) show two tone data restored from three tone data for " A "

Fig. 10 is a block diagram for explaining the function of the gradation shared data processing system of the first embodiment of the present invention.

11 is a block diagram showing a hardware configuration of a gradation shared data generating apparatus and a gradation shared data restoration apparatus included in the gradation shared data processing system;

12 is a flowchart showing a processing procedure in the outline information expansion and contraction unit 102 and the basic gradation value calculation unit 103.

FIG. 13 is a diagram showing a state of the expansion buffer 104 at the time when the processing in the outline information expansion and contraction unit 102 is finished.

FIG. 14 is a diagram showing a state of the expansion buffer 104 at the time when the processing in the basic gray scale value calculating section 103 ends.

15 is a flowchart showing a processing sequence in the gradation shared data generating unit 105.

FIG. 16 is a diagram showing a matrix table used for obtaining gradation shared data from gradation values of two gradation data and gradation values of three gradation data in the gradation sharing data generating unit 105. FIG.

FIG. 17 is a diagram showing gradation values of gradation shared data for each pixel of the alphabet " A " obtained by using a matrix table; FIG.

18 (a) and 18 (b) are diagrams showing conversion tables when converting grayscale values of grayscale shared data into grayscale values of two-tone data and three-tone data;

Fig. 19 shows the alphabet " A " by two tone data generated from tone shared data.

Fig. 20 is a diagram showing the alphabet " A " by three tone data generated from tone shared data.

21 is a diagram showing the configuration of a satellite broadcasting system using the present gradation data processing system;

FIG. 22 is a diagram showing a first configuration example of gradation shared data stored in STB503. FIG.

FIG. 23 is a diagram showing a second structural example of gradation shared data stored in STB503. FIG.

FIG. 24 is a diagram showing a third structural example of gradation shared data stored in STB503. FIG.

Fig. 25 is a block diagram for explaining the configuration of a gradation shared data processing system according to a second embodiment of the present invention.

26 (a), 26 (b) and 26 (c) show the outline information and stroke information of the Chinese character " three "

FIG. 27 is a flowchart showing the procedure of the processing in the first contour information expansion and contraction unit 2103 (the same as the processing in the second contour information expansion and reduction unit 2105 as described later).

(A), (b) and (c) of FIG. 28 enlarge and reduce the outline information and stroke information shown in (a), (b) and (c) of FIG. 26 to be suitable for generating two tone data. Figure showing data after

FIG. 29 is a view showing the contour information of FIG. 28B deployed on a submesh; FIG.

FIG. 30 is a first gradation value calculator 2104 showing gradation values of two gradation data for each pixel obtained from the enlarged and reduced contour information of "three" in FIG.

(A), (b) and (c) of FIG. 31 are enlarged and reduced the outline information and stroke information shown in (a), (b) and (c) of FIG. 26 to be suitable for generating three tone data. Figure showing the data after

FIG. 32 is a view showing contour information of FIG. 31B deployed on a submesh; FIG.

FIG. 33 is a second gradation value calculating unit 2206 which shows gradation values of three gradation data for each pixel obtained from the enlarged and reduced contour information of " three "

Fig. 34 is a view showing the gradation value of the gradation sharing data for " three " generated by the gradation sharing data generation unit 2107. Figs.

Fig. 35 is a diagram showing two tone data for " 3 " restored by the tone sharing data restoration apparatus of the tone sharing data processing system viewed from the tone sharing data.

Fig. 36 is a flowchart showing the processing procedure for each horizontal stroke of the two-tone data using the stroke adjusting unit of the tone-sharing data generating device of this modification.

37A and 37B show positions of four kinds of Y coordinate values L2 and L3 and Y coordinate values (assuming that Y coordinate values L2 and L3 are included in the same pixel). L2), a diagram showing the gradation value of the gradation data of the two gradation data, the gradation value of the three gradation data, and the gradation value of the gradation shared data generated therefrom according to the position of the Y coordinate value L3.

38A and 38B illustrate a Y coordinate value L2 when a pixel including the Y coordinate value L2 is in contact with a lower side of the pixel including the Y coordinate value L3. The gradation value of the two gradation data for the target pixel, the gradation value of the three gradation data, according to the four kinds of positions of the Y coordinate value L3, the positions of the Y coordinate value L2 and the Y coordinate value L3, A diagram showing gradation values of gradation shared data generated from

39 (a) and 39 (b) show the Y coordinate value L2 when the pixel including the Y coordinate value L2 is in contact with the upper side of the pixel including the Y coordinate value L3. The gray scale value of the two-gradation data and the three-gradation data corresponding to the four kinds of positions of the Y coordinate value (L3 + W3), the positions of the Y coordinate value (L2) and the Y coordinate value (L3) Diagram showing gradation values of gradation shared data generated from them

40 is a block diagram for explaining a configuration of a gradation shared data processing system according to a third embodiment of the present invention.

41 is a diagram showing an example of a color lookup table;

In order to achieve the above object, the apparatus for generating gradation sharing data according to the present invention comprises gradation data for representing the symbol corresponding to a predetermined number of pixels representing the gradation from contour information representing the outline of a symbol including a character or a figure. A gradation sharing data generating apparatus for sharing plural kinds and generating gradation sharing data, comprising: generating gradation data of p type maximum gradation number q _α (α = 1, 2, ..., p) from the outline information p (p is an integer of 2 or more) gradation data generating means, wherein m is an integer of 2 or more, and q _α is 2 ≤ q ₁ q _{2 ...} q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . an integer that satisfies q _p , and includes gradation shared data generating means for generating gradation shared data having a maximum number of gradations n from the p-type gradation data, wherein n is an integer that satisfies q _p n ≦ 2 ^m It can be done.

According to the gradation shared data generating device, gradation data of p type maximum gradation number q _α satisfying the above condition is generated from the contour information, and from _plural gradation data of these p type gradation data of the maximum gradation number n Gray scale shared data is generated.

As a result, the grayscale shared data of the maximum number of grayscales n is represented by the same number of bits as the grayscale data of the largest grayscale number q _p , and is generated from grayscale data of the p type of maximum grayscale number q _α , thereby increasing the data amount compared with the grayscale data. It is possible to generate gradation sharing data sharing a plurality of gradation data constituted of different maximum gradation numbers without causing deterioration of the data to be restored and without causing deterioration.

The gradation data generating means includes basic gradation data generating means for generating basic gradation data representing a ratio of an area of an inner part of the contour to each of the pixels from the contour information; Each of may generate grayscale data corresponding to the maximum grayscale number q _α from the basic grayscale data.

According to the grayscale shared data generating device, basic grayscale data indicating a ratio of the area of the inner portion of the outline occupied in each of the pixels from the outline information is generated, and grayscale data corresponding to the maximum gray number q _α is generated from the basic grayscale data. , the grayscale shared data of the maximum number of grayscales n is generated from p kinds of grayscale data.

As a result, the grayscale shared data of the maximum number of grayscales n is represented by the same number of bits as the grayscale data of the largest grayscale number q _p , and is generated from grayscale data of the p type of maximum grayscale number q _α , thereby increasing the data amount compared with the grayscale data. It is possible to generate gradation sharing data sharing plural kinds of gradation data composed of different maximum gradation numbers without causing deterioration of the data to be restored and without deterioration.

The gradation sharing data generating apparatus includes setting means for setting a threshold value, and each of the p gradation data generating means uses gradation data according to the maximum gradation number q _α using the threshold value set from the basic gradation data. Can be generated.

According to the gradation shared data generating apparatus, basic gradation data indicating a ratio of the inner portion of the contour occupying each pixel is generated from the contour information, and gradation according to the maximum gradation number q _α is generated by using a threshold set from the basic gradation data. Data is generated, and grayscale shared data of the maximum number of grayscales n is generated from p-type grayscale data.

As a result, the grayscale shared data of the maximum number of grayscales n is represented by the same number of bits as the grayscale data of the largest grayscale number q _p , and is generated from grayscale data of the p type of maximum grayscale number q _α , thereby increasing the data amount compared with the grayscale data. It is possible to generate gradation sharing data that share a plurality of gradation data types having different maximum gradation numbers without causing deterioration of the data to be restored and without restoration. In addition, by setting these thresholds according to a user's or program's request, it is possible to generate grayscale shared data that can maximize display capability based on information such as display characteristics.

In the gradation sharing data generating apparatus, the gradation sharing data generating means has a branch (q ₁ × q ₂ ×... Q _p ) for the gradation obtained by each of the gradation data having the maximum gradation number q _α . For the combination, the gradation data with the maximum gradation number n can be generated by allocating the gradation obtained by the gradation data with the maximum gradation number n.

According to the gradation shared data generating apparatus, gradation data of the p type maximum gradation number q _α is generated from the contour information, and (q ₁ × q ₂ × ...) for gradation obtained by each of the gradation data of the maximum gradation number q _α is obtained. By assigning the gradation of obtaining the gradation data of the maximum gradation number n to the combination of x q _p ), n kinds of gradation shared data are generated from these p kinds of gradation data.

This is expressed by the same number of bits as the gradation data of the gradation share maximum gradation number q _p of the maximum gradation number n, and is generated from the gradation data of the p kinds of gradation numbers q _α , so that the data amount is not increased compared with the gradation data. It is possible to generate gradation sharing data sharing plural kinds of gradation data composed of different maximum gradation numbers without causing deterioration of the restored data.

Further, the apparatus for generating gradation sharing data according to the present invention corresponds to a predetermined number of pixels representing gradation from contour information indicating the outline of a symbol including a character or a figure and stroke information indicating the position of the stroke constituting the symbol. In a gradation sharing data generating apparatus for sharing plural kinds of gradation data for representing a symbol and generating gradation sharing data, a p-type maximum gradation number q _α (α) while performing hint processing from the outline information and the stroke information. P (p is an integer of 2 or more) gradation data generating means for generating gradation data of = 1, 2, ..., p), wherein m is an integer of 2 or more, and q _α is 2 ≤ q ₁ q ₂ . . . q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . an integer that satisfies + _p , and includes gradation shared data generating means for generating gradation shared data having a maximum number of gradations n from the p-type gradation data, wherein n is an integer that satisfies q _p n ≤ 2 ^m It can be done.

According to the gray level shared data generating apparatus, the contour information and while a hint processing performed from the stroke information, grayscale data of the p-type of the maximum gradation number q _α is produced, the maximum from the grayscale data of those of the p-type, the maximum number of gray scale q _α Grayscale shared data of the grayscale number n is generated.

Accordingly, the grayscale shared data of the maximum grayscale number n is represented by the same number of bits as the grayscale data of the maximum grayscale number q _p , and is generated from the grayscale data of the p type maximum grayscale number q _α , so that the data amount is compared with the grayscale data. It is possible to generate gradation shared data sharing plural kinds of gradation data composed of different maximum gradations without causing deterioration and deterioration of the restored data. In addition, since the gray scale data is generated while the hint process is performed, and the gray scale shared data is generated, high quality gray scale data can be restored from the gray scale shared data.

The apparatus for generating gradation shared data includes adjusting means for adjusting stroke information for generating gradation data of another type (p-1) on the basis of stroke information on one type of gradation data among the p kinds of generated p types. can do.

According to the gradation shared data generating device, a hint process is performed from the contour information and the stroke information, and the stroke information for one type of gradation data among the p kinds to be generated is used as a reference, and the gradation of other (p-1) types is used as a reference. while adjusting the stroke information for generating the data, the gray scale data of the p-type, the maximum number of gray scale q _α is generated, gradation shared data is generated for the maximum gray level n from the grayscale data of those of the p-type, the maximum number of gray scale q _α do.

Accordingly, the grayscale shared data of the maximum number of grayscales n is represented by the same number of bits as the grayscale data of the largest grayscale number q _p , and is also generated from the grayscale data of the p type maximum grayscale number q _α , so that the data amount is compared with the grayscale data. It is possible to generate gradation sharing data sharing plural kinds of gradation data made up of different maximum gradations without causing degradation of the data to be restored and without increasing the number of times. In addition, gray scale data is generated while the hint processing is performed, and the stroke information subjected to the hint processing is corrected as necessary, and gray scale shared data is generated, so that gray scale data of higher quality can be restored from the gray scale shared data.

The gradation shared data decoding apparatus according to the present invention restores gradation data from gradation data sharing gradation data for representing a symbol including a character or a figure corresponding to a predetermined number of pixels indicating gradation. In the restoring apparatus, the tone sharing data is such that the maximum tone number n is obtained from the tone data of p type maximum tone number q _α (p is an integer of 2 or more and α = 1, 2, ..., p). M is an integer of 2 or more, q _α is 2 ≦ q ₁ q ₂ .. q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . + is an integer that satisfies _p , and n is an integer that satisfies q _p n ≤ 2 ^m , and the maximum number of gray level selection means for selecting the maximum number of gray levels, and the gray level which is the selected maximum gray number from the generated gray level shared data. And grayscale data restoration means for restoring data.

According to the grayscale shared data restoring apparatus, the maximum grayscale number is selected, and grayscale data which is the maximum grayscale number selected from the grayscale shared data is restored.

As a result, the grayscale data is restored without causing degradation of the data from the grayscale shared data of the maximum grayscale number n expressed by the same number of bits as the grayscale data of the maximum grayscale number q _p .

In the gradation shared data restoring apparatus, the gradation shared data restoring means restores the gradation data by allocating a gradation acquired by the gradation shared data to a gradation obtained by the gradation data of the selected maximum gradation number. Can be.

According to the gradation shared data restoring apparatus, the gradation which is the maximum gradation number selected from the gradation shared data by assigning the gradation acquired by the gradation shared data to the gradation obtained by the gradation data of the maximal number selected gradation data is selected. The data is restored.

In this way, the grayscale data is restored from the grayscale shared data of the maximum grayscale number n represented by the same number of bits as the grayscale data of the maximum grayscale number q _p without causing any deterioration of the data.

The gradation shared data restoring apparatus further includes storage means for storing p kinds of tables which correspond to gradations acquired by each of the p kinds of gradation data and gradations acquired by the gradation shared data, and recovering the gradation shared data. The means may be configured to perform the assignment using a table corresponding to the gradation data of the selected maximum gradation number among the stored p kinds of tables.

According to the gradation shared data restoring apparatus, the maximum gradation number is selected, and the gradation data of the selected maximal gradation number in the p-type table that associates the gradation to be obtained for each of the p kinds of gradation data with the gradation to be acquired for the gradation shared data is selected. By using the corresponding table, gradation data which is the maximum gradation number selected from the gradation sharing data is restored by allocating the gradation obtained by the gradation sharing data to the gradation obtained by the gradation data of the selected maximum gradation number.

In this way, the gray scale data is restored without causing deterioration of data from the gray scale shared data of the maximum gray number n expressed by the same number of bits as the gray data of the maximum gray number q _p using a simple configuration.

The gradation shared data restoration apparatus further includes determining means for determining whether gradation data of the selected maximum gradation number is included in the gradation sharing data, and gradation data of the selected maximum gradation number included in the gradation sharing data. And when it is determined that it is not, the external notification means for notifying the outside that the tone data, which is the selected maximum tone number, cannot be restored.

According to the grayscale shared data restoring apparatus, when the maximum number of grayscales is selected, grayscale data which is the maximum grayscale number selected from grayscale shared data is restored, and grayscale data of the selected maximum grayscale number is not included in the grayscale shared data, this is notified to the outside. do.

As a result, the grayscale data is restored from the grayscale shared data of the maximum grayscale number n expressed by the same number of bits as the grayscale data of the maximum grayscale number q _p without causing any deterioration of the data. In addition, when grayscale data of the selected maximum grayscale number is not included in the grayscale shared data, it is notified to the outside, thereby making it possible to stably perform the processing.

The gradation sharing data restoring apparatus includes determining means for determining whether gradation data of the selected maximum gradation number is included in the gradation sharing data, and gradation data of the selected maximum gradation number is included in the gradation sharing data. And when it is determined that there is no, the second maximum tone number selection means for selecting the maximum number of gray levels having a small difference from the selected maximum number of gray levels.

According to the gradation shared data restoring apparatus, the maximum gradation number is selected, the gradation data of the maximal gradation number selected from the gradation sharing data is restored, and when the gradation data of the selected maximum gradation number is not included in the gradation sharing data, The maximum number of grayscales with a small difference from the number of grayscales is again selected, and the grayscale data of the maximum selected grayscale number is restored from the grayscale shared data.

As a result, the grayscale data is restored from the grayscale shared data of the maximum grayscale number n expressed by the same number of bits as the grayscale data of the maximum grayscale number q _p without causing any deterioration of the data. Also, when grayscale data of the selected maximum grayscale number is not included in the grayscale sharing data, the maximum grayscale number having a small difference from the selected maximum grayscale number is selected again to restore the grayscale data so that the grayscale data is used in real time and the symbol is displayed. In such a case, the display can be performed smoothly without interruption, and stable processing can be performed.

The gradation shared data restoring apparatus may further include assigning means for allocating a color in a predetermined color lookup table to the gradations acquired by the restored gradation data.

According to the gradation shared data restoring apparatus, the maximum gradation number is selected, gradation data which is the maximum gradation number selected from the gradation sharing data is restored, and the gradation obtained by the restored gradation data is assigned a color in a predetermined color lookup table. do.

As a result, the grayscale data is recovered from the grayscale shared data of the maximum grayscale number n expressed by the same number of bits as the grayscale data of the maximum grayscale number q _p without causing degradation of the data. In addition, since the color in the predetermined color lookup table is assigned to the gray level obtained by the restored gray level data, a high quality gray level can be obtained.

In addition, the gradation shared data restoration apparatus is configured to perform the restoration of the gradation data of three or more gradations (except foreground colors and background colors) from the data specifying the foreground color and the background color among the predetermined color lookup tables. Calculating means for calculating data specifying each of the intermediate colors of gradation or higher, and assigning means of allocating a color included in a predetermined range from the calculated data in the color lookup table for each of the intermediate colors of the gradation or higher; I can do it.

According to the gradation shared data restoring apparatus, the maximum gradation number is selected, gradation data which is the maximum gradation number selected from the gradation sharing data is restored, and restored from the data specifying the foreground color and the background color in the predetermined color lookup table. Data specifying each of one or more intermediate colors for the three or more gradation data (except the foreground color and the background color) is calculated, and predetermined data is calculated from the calculated data in the color lookup table for each of the one or more gradations. Colors in the range are assigned.

As a result, the grayscale data is recovered from the grayscale shared data of the maximum grayscale number n expressed by the same number of bits as the grayscale data of the maximum grayscale number q _p without causing degradation of the data. In addition, since the color included in the predetermined range is allocated to each of the one or more gradation colors from the calculated data in the color lookup table, a higher quality gradation can be obtained.

A gradation data processing apparatus according to the present invention is a gradation data processing apparatus for processing gradation data for representing a symbol including a character or a figure in correspondence with a predetermined number of pixels representing a gradation,

Calculating means for calculating data specifying one or more gradations for the gradation data of three or more gradations (except the foreground color and the background color) from data specifying the foreground color and the background color in the predetermined color lookup table; And allocating means for allocating a color included in a predetermined range from the calculated data in the color lookup table for each of the one or more gradations.

According to the gradation data processing apparatus, each of one or more gradations for gradation data (except foreground color and background color) for three or more gradations from the data for specifying the foreground color and the background color in the predetermined color lookup table is specified. Data is calculated, and a color included in a predetermined range is assigned from each of the calculated data in the color lookup table for each of the one or more gradations.

As a result, characters and figures can be expressed using high quality gradations.

The gradation sharing data generating apparatus according to the present invention shares a plurality of types of gradation data for representing the symbol in accordance with a predetermined number of pixels indicating the gradation from the contour information representing the outline of the symbol including a character or a figure. In the gradation shared data generating device for generating shared data,

First gradation data generating means for generating gradation data of maximum gradation number 2 from the contour information, second gradation data generating means for generating gradation data of maximum gradation number 3 from the contour information, and the generated maximum gradation number And gradation shared data generating means for generating gradation shared data of maximal gradation number 4 from gradation data of 2 and gradation data of maximal number 3.

According to the grayscale shared data generating device, grayscale data of the maximum gray number 2 and grayscale data of the maximum gray number 3 are generated from the contour information, and grayscale shared data of the maximum gray number 4 is generated from these grayscale data.

As a result, the gradation shared data of the maximum gradation number 4 is represented by the same number of bits as the gradation data of the maximum gradation number 3, and is generated from two kinds of gradation data, so that the deterioration of the data to be restored without increasing the amount of data. It is possible to generate gradation sharing data without creating a.

The gradation shared data restoration apparatus according to the present invention restores gradation data from gradation data sharing gradation data for representing a plurality of gradation data for representing a symbol including a character or a figure corresponding to a predetermined number of pixels representing the gradation. In the restoration device,

The grayscale sharing data is generated to have a maximum number of grayscales 4 from grayscale data of the maximum grayscale number 2 and grayscale data of the maximum grayscale number 3, and the maximum grayscale number selection means for selecting the maximum grayscale number 2 or the maximum grayscale number 3; And gradation shared data restoring means for restoring gradation data which is the selected maximum gradation number from the gradation sharing data.

According to the grayscale shared data restoring apparatus, the maximum grayscale number 2 or the maximum grayscale number 3 is selected, and the grayscale data of the maximum grayscale number selected from the grayscale shared data is restored.

Accordingly, the gradation data is restored without causing deterioration of the data from the gradation shared data of the maximum gradation number 4 represented by the same number of bits as the gradation data of the maximum gradation number 3.

The method for generating gradation sharing data according to the present invention shares a plurality of types of gradation data for representing the symbol corresponding to a predetermined number of pixels indicating the gradation from contour information representing the outline of a symbol including a character or a figure, and shares the gradation. A gradation shared data generation method for generating data, wherein p (p is an integer of 2 or more) for generating gradation data of p type maximum gradation number q _α (α = 1, 2, ..., p) from the outline information. ) Gray level data generating step, wherein m is an integer of 2 or more, and q _α is 2 ≦ q ₁ q ₂ . . . q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . + q _p is an integer that satisfies a gray level shared data generation step of generating a gray level shared data having a maximum number of gray levels n from the p type gray level data, and n is an integer that satisfies q _p n ≤ 2 ^m It can be done.

According to the method for generating gradation shared data, gradation data of p type maximum gradation number q _α satisfying the above condition is generated from the contour information, and gradation of maximum gradation number n satisfying the above condition from these p type gradation data Shared data is generated.

Accordingly, the grayscale shared data of the maximum grayscale number n is represented by the same number of bits as the grayscale data of the maximum grayscale number q _p , and is generated from the grayscale data of the p type maximum grayscale number q _α , so that the data amount is compared with the grayscale data. It is possible to generate gradation shared data that shares a plurality of gradation data types having different maximum gradation numbers without causing an increase and deterioration of the restored data.

In addition, the method for generating gradation sharing data according to the present invention corresponds to the predetermined number of pixels indicating gradation from contour information indicating the outline of a symbol including a character or a figure and stroke information indicating the stroke position constituting the symbol. A gradation shared data generation method for sharing plural kinds of gradation data for representing a symbol and generating gradation sharing data, wherein the p-type maximum gradation number q _α (α) while performing hint processing from the outline information and the stroke information. P (p is an integer of 2 or more) gradation data generating steps for generating gradation data of = 1, 2, ..., p), wherein m is an integer of 2 or more, and q _α is 2 ≤ q ₁ q ₂ . . . q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . _P + q is an integer satisfying comprising: a gray level shared data generation step of generating a gray level of n shared data maximum number of gradations from gradation data of the generated p type, n is an integer satisfying q _p n≤ 2 ^m It can be done.

According to the method for generating gradation shared data, gradation data of p type maximum gradation number q _α is generated while performing hint processing from contour information and stroke information, and maximal gradation from gradation data of these p type maximum gradation number q _α A number n of gradation shared data are generated.

Accordingly, the grayscale shared data of the maximum grayscale number n is represented by the same number of bits as the grayscale data of the maximum grayscale number q _p , and is generated from the grayscale data of the p type maximum grayscale number q _α , so that the data amount is compared with the grayscale data. It is possible to generate gradation shared data sharing plural kinds of gradation data composed of different maximum gradations without causing increase and deterioration of the data to be restored. In addition, since the gray scale data is generated as the hint process is performed to generate the gray scale shared data, it is possible to restore high quality gray scale data from the gray scale shared data.

The gradation shared data restoration method according to the present invention is a gradation shared data for restoring gradation data from gradation shared data sharing plural kinds of gradation data for representing a symbol including a character or a figure corresponding to a predetermined number of pixels representing gradations. In the restoration method, the grayscale shared data is such that p-type maximum grayscale number q _α (p is an integer of 2 or more, and has a maximum grayscale number n from grayscale data of α = 1, 2, ..., p). M is an integer of 2 or more, q _α is 2 ≦ q ₁ q ₂ .. q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . + is an integer satisfying q _p , n is an integer that satisfies q _p n ≤ 2 ^m , and a maximum number of tones selection step of selecting a maximum number of gray levels, and a gray level which is the selected maximum number of gray levels from the generated gray level shared data. And a gradation share data restoration step of restoring the data.

According to the grayscale shared data restoration method, the maximum grayscale number is selected, and grayscale data of the selected maximum grayscale number is restored from the grayscale shared data.

Accordingly, the gradation is expressed by the same number of bits as the gradation data of the maximum gradation number q _p , and without causing data degradation from gradation shared data of the maximum gradation number n generated from the gradation data of the p type maximum gradation number q _α . The data is restored.

In the gradation data processing method according to the present invention, in the gradation data processing method for processing gradation data for representing a symbol including a character or a figure corresponding to a predetermined number of pixels representing the gradation,

A calculation step of calculating data for specifying each of one or more gradation colors for gradation data of three or more gradations (excluding the foreground and background colors) from the data specifying the foreground color and the background color among the predetermined color lookup tables; And assigning a color included in a predetermined range from the calculated data in the color lookup table to each of the one or more gradations.

According to the gradation data processing method, each of one or more gradation colors for gradation data of three or more gradations (except foreground color and background color) is identified from the data specifying the foreground color and the background color in the predetermined color lookup table. The data to be calculated is calculated, and a color included in a predetermined range is allocated from each of the calculated data in the color lookup table to each of one or more gradations.

As a result, characters and figures can be expressed using high quality gradations.

In addition, the method for generating gradation sharing data according to the present invention includes gradation for sharing a plurality of types of gradation data for representing the symbol corresponding to a predetermined number of pixels indicating the gradation from the contour information representing the outline of the symbol including a character or a figure. In the gradation shared data generation method for generating shared data,

A first gradation data generation step of generating gradation data of the maximum gradation number 2 from the contour information, a second gradation data generation step of generating gradation data of the maximum gradation number 3 from the contour information, and the generated maximum gradation number And gradation shared data generation step of generating gradation shared data of maximal gradation number 4 from gradation data of 2 and gradation data of maximum gradation number 3.

According to the method for generating gradation shared data, gradation data of up to 2 gradations and gradation data of up to 3 gradations is generated from the contour information, and gradation sharing data of up to 4 gradations is generated from these gradation data.

As a result, the gradation shared data of the maximum gradation number 4 is represented by the same number of bits as the gradation data of the maximum gradation number 3, and since it is generated from two kinds of gradation data, it does not increase the data amount and also causes deterioration of the restored data. The gray scale shared data can be generated.

In the gradation sharing data restoration method according to the present invention, gradation sharing for restoring gradation data from gradation sharing data sharing plural kinds of gradation data for representing a symbol including a character or a figure corresponding to a predetermined number of pixels indicating gradation. In the data recovery apparatus,

The grayscale sharing data is generated to have a maximum number of grayscales 4 from grayscale data of the maximum grayscale number 2 and grayscale data of the maximum grayscale number 3, and selects the maximum grayscale number 2 or the maximum grayscale number 3; And gradation shared data restoring step of restoring gradation data which is the selected maximum gradation number from the gradation sharing data.

According to the grayscale shared data restoration method, the maximum grayscale number 2 or the maximum grayscale number 3 is selected, and grayscale data of the maximum grayscale number selected from the grayscale shared data is restored.

As a result, the grayscale data is restored without causing degradation of the data from the grayscale shared data of the maximum grayscale number 4 represented by the same number of bits as the grayscale data of the maximum grayscale number 3.

A computer-readable recording medium for recording a program according to the present invention includes a plurality of types of gradation data for representing the symbol in response to a predetermined number of pixels indicating the gradation from contour information representing the outline of a symbol including a character or a figure. A computer-readable recording medium for sharing, generating gradation sharing data, and recording a program, the p-type maximum gradation number q _α (p being an integer of 2 or more, α = 1, 2,. .., p) Grayscale data is generated, and a program for generating grayscale shared data having a maximum number of grayscale n from the generated p-type grayscale data is recorded, wherein m is an integer of 2 or more, q _α is 2 ≤ q ₁ q ₂ .. q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . It is an integer satisfying _p + q, n may be an integer satisfying q _p n ≤ 2 ^m.

According to the program, gradation data of the p type maximum gradation number q _α satisfying the above condition is generated from the contour information, and gradation shared data having the maximum gradation number n satisfying the above condition from these p kind of gradation data is generated. Is generated.

Accordingly, the grayscale shared data of the maximum grayscale number n is represented by the same number of bits as the grayscale data of the maximum grayscale number q _p , and is generated from the grayscale data of the p type maximum grayscale number q _α , so that the data amount is compared with the grayscale data. It is possible to generate gradation sharing data sharing plural kinds of gradation data composed of different maximum gradations, without increasing the number of pixels and without causing deterioration of the restored data.

A computer-readable recording medium for recording a program according to the present invention includes outline information indicating the outline of a symbol including a character or a figure, and stroke information indicating the position of the stroke constituting the symbol. A computer-readable recording medium for sharing plural types of gradation data for representing the symbols, generating gradation sharing data, and recording a program, wherein the p-types are performed while performing hint processing from the outline information and the stroke information. Grayscale data with the maximum number of grayscales q _α (p is an integer of 2 or more and α = 1, 2, ..., p) is generated, and the grayscale with the maximum grayscale number n is generated from the generated p type grayscale data. A program for generating shared data is recorded, wherein m is an integer of 2 or more, and q _α is 2 ≦ q ₁ q _{2 ...} q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . It is an integer satisfying _p + q, n may be an integer satisfying q _p n ≤ 2 ^m.

According to the program, while the hint process carried out from the outline information and stroke information, grayscale data of the p-type of the maximum gradation number q _α is produced, the maximum number of gradations n from the grayscale data of those of the p-type, the maximum number of gray scale q _α Gray scale shared data is generated.

Accordingly, the grayscale shared data of the maximum number of grayscales n is represented by the same number of bits as the grayscale data of the largest grayscale number q _p , and is also generated from the grayscale data of the p type maximum grayscale number q _α , so that the data amount is compared with the grayscale data. It is possible to generate gradation sharing data sharing plural kinds of gradation data composed of different maximum gradations, without increasing the number of pixels and without causing deterioration of the restored data. In addition, since the gray scale data is generated while the hint process is performed, and the gray scale shared data is generated, high quality gray scale data can be restored from the gray scale shared data.

A computer-readable recording medium for recording a program according to the present invention restores gray scale data from gray scale shared data for sharing a plurality of types of gray scale data for representing a symbol including a character or a figure corresponding to a predetermined number of pixels indicating gray scale. In the computer-readable recording medium for recording a program, the gradation shared data is a gradation of p-type maximum gradation number q _α (p is an integer of 2 or more and α = 1, 2, ..., p) It was generated to have the maximum number of gray scales n from the data, m is an integer of 2 or more, q _α is 2 ≦ q ₁ q ₂ .. q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . + is an integer satisfying q _p , n is an integer satisfying q _p n ≤ 2 ^m , selects a maximum number of gray levels, and restores the gray level data which is the selected maximum gray number number from the generated gray level shared data. You can record.

According to the program, the maximum number of gray levels is selected, and the gray level data which is the maximum number of gray levels selected from the gray level shared data is restored.

As a result, the grayscale data is restored without causing degradation of the data from the grayscale shared data of the maximum grayscale number n expressed by the same number of bits as the grayscale data of the maximum grayscale number q _p .

A computer-readable recording medium for recording a program according to the present invention is a computer-readable recording medium for recording a program for processing grayscale data for representing a symbol including a character or a figure corresponding to a predetermined number of pixels representing a grayscale. In the medium,

From the data specifying the foreground color and the background color in the predetermined color look-up table, data specifying each of one or more gradation colors for gradation data of three or more gradations (except foreground colors and background colors) is calculated, and the 1 A program for allocating a color included in a predetermined range from the calculated data in the color lookup table for each of the intermediate colors of the gradation or more can be recorded.

According to the program, data for specifying each of one or more gradations for gradation data of three or more gradations (except for foreground and background colors) from data specifying a foreground color and a background color in a predetermined color look-up table is provided. The color included in the predetermined range is allocated from the calculated data in the color lookup table to each of the intermediate colors of one or more gradations.

As a result, characters and figures can be expressed using high quality gradations.

A computer-readable recording medium for recording a program according to the present invention includes a plurality of types of gradation data for representing the symbol corresponding to a predetermined number of pixels indicating the gradation from the contour information representing the outline of the symbol including a character or a figure. A computer-readable recording medium for sharing, generating gradation sharing data, and recording a program,

A program for generating grayscale data with the maximum number of grayscales and grayscale data with the maximum number of grayscales from the outline information, and generating grayscale data with the maximum number of grayscales from four generated grayscale data; have.

According to the program, grayscale data with a maximum number of grayscales and grayscale data with a maximum number of grayscales is generated from the outline information, and grayscale shared data with a maximum number of grayscales is generated from the two kinds of generated grayscale data.

As a result, the gradation shared data of the maximum gradation number 4 is represented by the same number of bits as the gradation data of the maximum gradation number 3, and is generated from two kinds of gradation data, so that the deterioration of the data to be restored without increasing the amount of data. It is possible to generate gradation sharing data without creating a.

A computer-readable recording medium for recording a program according to the present invention includes gradation data from gradation sharing data sharing plural kinds of gradation data for representing a symbol including a character or a figure corresponding to a predetermined number of pixels representing gradations. A computer-readable recording medium for recording a program to be restored,

The grayscale shared data is generated to have a maximum number of grayscales 4 from grayscale data having a maximum number of grayscales 2 and grayscale data having a maximum number of grayscales, and selects a maximum grayscale number, and selects the selected maximum grayscale number from the generated grayscale shared data. The program for restoring the grayscale data can be recorded.

According to the program, the maximum number of tones is selected, and the tone data which is the maximum number of tones selected from the generated tone sharing data is restored.

As a result, the grayscale data is restored without causing degradation of the data from the grayscale shared data of the maximum grayscale number 4 represented by the same number of bits as the grayscale data of the maximum grayscale number 3.

A computer-readable recording medium for recording gradation sharing data according to the present invention shares a plurality of types of gradation data for representing symbols including letters or figures, corresponding to a predetermined number of pixels representing gradations, a computer-readable recording medium for recording, are respectively produced from the contour information representing the contour of the symbol and the p type, the maximum number of gray scale q _α (p to an integer of 2 or more, α = 1, 2, ..., The grayscale shared data generated to have the maximum number of grayscales n from the grayscale data of p) is recorded, wherein m is an integer of 2 or more, and q _α is 2 ≦ q ₁ q _{2 ...} q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . It can be set as an integer satisfying + q _p .

The gray level shared data may be so generated such that the maximum number of gradations n expressed by the maximum number of bits, such as gray-scale data of q _p gradation from the gradation data p type being created respectively from the contour information such that the maximum gradation number q _α, data P kinds of grayscale data can be restored without causing deterioration.

In addition, a computer-readable recording medium for recording gradation sharing data according to the present invention, in response to a predetermined number of pixels representing gradation, shares a plurality of types of gradation data for representing a symbol including a character or a figure, and shares gradation. In a computer-readable recording medium for recording data,

It is possible to record gradation shared data which is generated from contour information representing the outline of the symbol and which is generated so as to have the maximum number of gradations 4 from the gradation data of the maximum gradation number 2 and the gradation data of the maximum gradation number 3.

This grayscale shared data is generated from the two kinds of grayscale data generated from the contour information so that the maximum grayscale number is 2 and the maximum grayscale number 3 is the maximum grayscale number 4, so that the same number of bits as the grayscale data of the maximum grayscale number 3 can be expressed. It is possible to restore two kinds of gradation data without causing deterioration of data.

The above and other objects and features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings.

(Example)

Hereinafter, a grayscale shared data processing system according to an embodiment of the present invention will be described with reference to the accompanying drawings.

First, the grayscale shared data processing system of the first embodiment of the present invention will be described.

FIG. 10 is a block diagram illustrating a function of a grayscale shared data processing system according to a first embodiment of the present invention, and FIG. 11 is hardware of a grayscale shared data generating device and a grayscale shared data restoring apparatus included in the grayscale shared data processing system. It is a block diagram which shows a structure.

The grayscale shared data processing system includes a grayscale shared data generating device and a grayscale shared data restoring device. As shown in FIG. 11, the grayscale shared data generating device and the grayscale shared data restoring device are respectively stored in the storage unit 1, ROM 2, RAM 3, CPU 4, display unit 5, and input unit 6 are included.

The storage unit 1 is a secondary storage device such as a hard disk, a floppy disk, a DVD-RAM, and the like, and stores program files, data files, and the like. The ROM 2 stores a program for generating gradation shared data (gradation sharing data generating apparatus) and a program for restoring gradation sharing data (gradation sharing data restoration apparatus) as described below. The RAM 3 is a memory used as a work area for temporary work.

The CPU 4 mainly generates gradation sharing data of the size indicated by the input unit 6 or the program from the outline data by executing a program stored in the ROM 2 (gradation sharing data generating device), and also gradation sharing. The tone data of the tone number indicated by the input unit 6 or the program is restored from the data and displayed on the display unit 5 (tone shared data restoration device).

The display unit 5 has a display device capable of gray scale display such as a liquid crystal panel and a CRT, and displays characters or graphics based on the gray scale data. The input unit 6 receives an instruction of an operation such as specifying the size of a character or a figure, the number of gradations, etc. from a user when generating or restoring gradation shared data.

As shown in Fig. 10, each of the gradation shared data generation device and the gradation shared data restoration device constituted by these hardware includes a function realized by the CPU 4 executing a program of the ROM 2. Here, for convenience of description, it is not possible to specify in advance which of the grayscale data having two kinds of (maximum) grayscale numbers is used as the grayscale shared data restoration apparatus, and the grayscale shared data from the two kinds of grayscale data as the grayscale shared data generating apparatus. Although it is assumed that is generated, the present invention can be similarly applied to grayscale data having three or more kinds of (maximum) grayscale numbers.

The apparatus for generating gradation shared data includes an outline information holding unit 101, an outline information expanding and contracting unit 102, a basic gradation value calculating unit 103, a development buffer 104, and a gradation sharing data generating unit 105. The grayscale shared data restoring apparatus includes a grayscale shared data extracting unit 106, a development buffer 107, a grayscale number selecting unit 108, a first grayscale data restoring unit 109, and a second grayscale data restoring unit 110. It is included.

In addition, the contour information holding unit 101, the expansion buffer 104, and the expansion buffer 107 of the grayscale shared data restoring apparatus of FIG. 10 are provided with an area on the RAM 3 in each device. Otherwise, this is a function realized by the CPU 4 executing a program stored in the R0M 2 in each device.

The operations of the respective portions of the gradation shared data generating device and the gradation shared data restoring device shown in FIG. 10 will be described.

In the gradation shared data generating apparatus, the outline information holding unit 101 shows the outline represented as a set of points representing the characteristic of the outline on a predetermined coordinate corresponding to each character (or figure) from the outline data which is the object of gradation shared data generation. Withdraw information and keep it.

Here, as described above, contour information representing the alphabet "A" of the Gothic font shown in Fig. 2A as a set of straight lines on the coordinates of 1000 mesh is used for explanation. As shown in (b) of FIG. 2, the contour information of "A" is composed of points in coordinates that can be divided into contour 1 and contour 2 for each continuous contour. Two outlines are drawn. In addition, although "A" which consists only of a straight line is demonstrated here, this invention can be similarly applied also to the character which a quadratic curve and a cubic curve use together.

The outline information enlargement and reduction unit 102 (refer to FIG. 10) enlarges and reduces the outline information held in the outline information holding unit 101 in accordance with the requested size. Here, as in the grayscale shared data generating apparatus of the conventional grayscale shared data processing system, the required size indicated is 10x10 pixels and 1 pixel is composed of 4x4 subpixels, and is included in the outline (contour image). It is assumed that the gray level value of each pixel is determined based on each pixel based on the sub-pixels (a number other than 4 may be used as the sub mesh).

The basic gray scale value calculator 103 calculates a basic gray scale value for each pixel based on the outline information (enlarged or reduced) by the outline information enlarged and reduced unit 102. The basic gradation value of each pixel is a value used as a basis for determining the gradation when generating gradation data of a plurality of gradations. Each pixel is composed of 4x4 = 16 subpixels, and a basic gray scale value of 0 to 16 is assigned corresponding to the number of subpixels included in the outline of the character.

The expansion buffer 104 is a temporary buffer which holds the basic gray level data of each pixel calculated by the basic gray level calculation unit 103 in the process of generating grayscale shared data, and the number of pixels according to the requested request size and one. Basic grayscale value data is held in subpixel units determined by the number of subpixels for dividing pixels. In this case, since the requested request size is 10x10 pixels and one pixel is composed of 4x4 subpixels, an area of 40x40 subpixels is occupied on the expansion buffer 104 for one character. do.

In addition, the gradation shared data generating unit 105 has a gradation value having a first gradation number and a second gradation for each pixel of the basic gradation value data developed in the expansion buffer 104 by the basic gradation value calculation unit 103. A tone value having a number is obtained, and tone sharing data for sharing a plurality of types of tone data composed of a plurality of these different tone numbers is generated.

In the grayscale shared data restoring apparatus, the grayscale shared data extracting unit 106 extracts the grayscale shared data generated by the grayscale shared data generating apparatus and stores it in the expansion buffer 107. The expansion buffer 107 is a temporary buffer that stores the grayscale shared data extracted by the grayscale shared data extracting unit 106 in the process of restoring the grayscale shared data.

The gradation number selection section 108 selectively activates either one of the first gradation data restoration section 109 and the second gradation data restoration section 110 by the requested gradation number.

The first gradation data restoring unit 109 obtains the gradation number having the first gradation number for each pixel from the gradation sharing data stored in the expansion buffer 107 according to the instruction from the gradation number selection unit 108, First grayscale data is generated. In addition, the second grayscale data restoring unit 110 obtains a grayscale value having a second grayscale number for each pixel from grayscale shared data stored in the expansion buffer 107 according to an instruction from the grayscale number selecting unit 108. Generate second tone data.

The procedure of processing in the gradation shared data generating apparatus and the gradation shared data restoration apparatus will be described.

Here, it is assumed that two gradation data is treated as the first gradation data and three gradation data is used as the second gradation data. As in the grayscale shared data processing system of the first and second conventional examples, a grayscale value of 1 for the foreground color and 0 for a background color is assigned to the grayscale value of the two-tone data for each pixel, and for the grayscale value of the three-tone data. It is assumed that 2 is assigned to the foreground color, 1 to the intermediate color, and 0 to the background color.

As a gradation shared data generating apparatus, the procedure from the outline data showing the outline of a character or a figure to the generation of the gradation shared data is described first as (process 1) to (process 4). Here, the processing for the alphabet "A" is taken as an example similarly to the description in the gradation sharing data processing system of the first and second conventional examples, but also for characters of Chinese characters, hiragana, katakana, other languages, and figures other than these. Similarly, the present invention can be applied.

(Process 1) For the first time, the outline information holding unit 101 (see FIG. 10) extracts outline information about a requested character from a storage unit (corresponding to the storage unit 1 in FIG. 11) that stores outline data. To keep it. Here, the outline information shown in Fig. 2B is obtained from the outline data and retained, similarly to the gradation shared data processing system of the first and second conventional examples.

(Process 2) The outline information expansion and contraction unit 102 supplies outline information expressed on the coordinates of 1000 meshes drawn out by the outline information holding unit 101 to 10 × 10 pixels (one pixel is 4 × 4 sub) as the required size. It is made up of pixels and is reduced (enlarged) to be suitable for 40 x 40 subpixels. (The outline information enlargement and reduction unit 102 can enlarge the outline information as necessary. However, the outline information is reduced.)

More specifically, each coordinate value included in the contour information is reduced using Equation 1 below.

Where SP is the coordinate value after reduction, OP is the coordinate value before reduction, Np is the number of pixels of the required size, Nsp is the number of submeshes, EM is the number of meshes for the original contour information, and trunc (X) is the argument (X Let's round off the value of). In this grayscale shared data generating device, Np is 10, Nsp is 4, and EM is 1000.

For example, the coordinate values 125 and 75 included in the contour information are reduced to the coordinate values 5 and 3 by applying Equation 1 above. Such reduction is repeated for the coordinate values included in the contour information shown in FIG. 2B to obtain contour information after reduction using the coordinate values corresponding to the subpixels shown in FIG. 4B.

(Process 3) The basic gradation value calculation unit 103 (see FIG. 10) obtains the basic gradation value of each pixel from the reduced contour information obtained by the contour information expansion and reduction unit 102, and expands it to the expansion buffer 104. . As described above, the basic gradation value of each pixel is determined by the number of sub-pixels constituting the pixel included in the outline represented by the contour information, but the basic gradation value is calculated using other calculations. You can also get

(Process 2) in the outline information expansion and contraction unit 102 and (Process 3) in the basic gradation value calculation unit 103 will be described in more detail using a flowchart.

12 is a flowchart showing the procedure of processing in the outline information expansion and contraction unit 102 and the basic gradation value calculation unit 103. FIG. 13 is a view showing the state of the expansion buffer 104 at the time when the processing in the outline information expansion and contraction unit 102 is finished, and FIG. 14 is the time when the processing in the basic gradation value calculation unit 103 is finished. The state of the expansion buffer 104 in FIG.

In the process of the outline information expansion and contraction unit 102, first, it is determined whether there is an unprocessed outline (corresponding to the outline 1 and the outline 2 of "A" shown in Fig. 2B) (S11). If there is an unprocessed outline (YES in S11), it is determined whether there is unprocessed outline information (corresponding to the coordinate values included in the outline 1 and outline 2 shown in Fig. 2B) in this outline. (S12).

If there is unprocessed outline information (YES in S12), the outline information of the unprocessed outline is enlarged and reduced and taken out (S13), and this coordinate value is plotted in the expansion buffer 104, and the process proceeds to S12 (S14). If there is no unprocessed outline information (NO in S12), all coordinate values plotted in the expansion buffer 104 are connected in a straight line (S15), and the process proceeds to S11. In addition, when all coordinate values which form this outline are connected by a straight line, an end point coordinate and a viewpoint coordinate are connected by a straight line.

After repeating these processes, if the unprocessed outline disappears (NO in S11), the process proceeds to the process in the basic gradation value calculating unit 103.

The state of the expansion buffer 104 at the time when the processing in the outline information expansion and contraction unit 102 is finished is as shown in FIG. FIG. 13 shows a state in which only the outline of "A" is drawn on the coordinates of the subpixels.

Subsequently, in the processing of the basic gradation value calculating unit 102, following the processing in the outline information expanding and contracting unit 102, it is determined whether or not there is an unprocessed pixel (S16). If there are unprocessed pixels (YES in S16), these unprocessed pixels are fetched from the expansion buffer 104 in a predetermined order (S17), and the basic gray level value for the pixels is determined from the number of subpixels included in the outline. It becomes (S18).

After repeating these processes, if an unprocessed pixel is lost (NO in S16), the process ends.

The state of the expansion buffer 104 at the time when the processing in the basic gradation value calculation unit 103 is finished is as shown in FIG. In FIG. 14, the state in which the basic gradation value has been calculated for each pixel as described above is shown (the gradation value of two gradations = 1 and the gradation value of three gradations = 1 in FIG. 14 will be described later.

(Process 4) The gradation shared data generating unit 105 (see Fig. 10) is shared with two gradation data and three gradation data from the basic gradation value for each pixel (in the state shown in Fig. 14). The resulting gray scale value (gradation value for the gray scale shared data) is obtained. This process will be described in more detail using a flowchart.

15 is a flowchart showing a procedure of processing in the gradation shared data generating unit 105. FIG. 16 is a diagram showing a matrix table used for obtaining gradation shared data from gradation values of two gradation data and gradation values of three gradation data in the gradation sharing data generation unit 105, and FIG. 17 is used by the matrix table. It is a figure which shows the gradation value of gradation shared data with respect to each pixel of the alphabet "A" calculated | required by this.

The grayscale shared data generating unit 105 first determines whether there is an unprocessed pixel (S21). If there is an unprocessed pixel (YES in S21), a basic gray value Lorg for this pixel is retrieved from the expansion buffer 104 (S22). Equations 2 and 3 below are applied to the extracted basic gradation value Lorg to obtain two gradation values (S23, S24, and S25).

Where L2 is the grayscale value in the two-tone data, SP is the number of subpixels constituting one pixel, and TH2 divides the basic grayscale value into the foreground color (gradation value 1) and the background color (gradation value 0) in the two grayscales. An integer value from 0 to SP is used as a threshold for doing this.

In this gradation shared data generating device, SP = 16 and TH2 = 8. That is, when the number of subpixels in the outline of the character is 8 or more, that is, when 1/2 or more of the pixels are gathered in the outline, the gradation value is 1, otherwise (less than half of the pixels are outlines). In the case of gathering inside the gradation value, the gray scale value is zero. A value other than this can be used for this threshold value TH2, and in order to determine the gradation value in the two gradation data, other than the above expressions (2) and (3) (for example, the basic gradation value and the gradation value of the two gradation data). Table showing the correspondence of?).

Subsequently, the following tone expressions (4) through (6) are applied to the basic tone value Lorg to obtain three tone values (S26, S27, S28, S29, and S30).

Where L3 is the gradation value in the 3rd gradation data, and TH31, TH32 (TH31TH32) separates the basic gradation value into the foreground color (gradation value 2), intermediate color (gradation value 1) and background color (gradation value 0) in the 3rd gradation. An integer value from 0 to SP is used as a threshold for this.

In this gradation shared data generating apparatus, TH31 = 5 and TH32 = 11. That is, in the case of the number of subpixels in the liminal tube of the character 16 to 11, the gradation value becomes 2, in the case of 10 to 5 the gradation value becomes 1, and in the case of 4 to 0, the gradation value becomes 0. . As described above, other values may be used for the thresholds TH31 and TH32, and other than the above Equations 4 to 6 to determine the gradation value in the three gradation data (for example, the basic gradation value and the three gradation data). A table indicating correspondence of the gradation values can be used.

The gradation value for gradation shared data by the matrix table shown in FIG. 16 for the gradation value (0 or 1) for the two gradation data after these processing and the gradation value (any one of 0 to 2) for the three gradation data. This is obtained (S31).

For example, the pixel of the basic gradation value 9 shown in Fig. 14 is calculated as the gradation value 1 from the 2 gradation data and the gradation value 1 from the 3 gradation data by the above-described processing, and the matrix table is used to make the gradation The gradation value 2 for the shared data is obtained (a matrix table for obtaining the gradation value for this gradation shared data can be used other than that shown in FIG. 16, and the gradation of the gradation shared data using a threshold or the like other than the matrix table is used. Value can be obtained).

By using the gray scale shared data for each pixel as described above, the gray scale value of the gray scale shared data for each pixel as shown in FIG. 17 is obtained.

In this grayscale shared data processing system, as shown in FIG. 16, grayscale shared data is represented by 2 bits (takes values from 0 to 3) for one pixel, and takes grayscale values of 0, 1, and 2. It has the same data size as the three-tone data.

Subsequently, the procedure of the process at the time of restoring the grayscale shared data generated by the grayscale shared data generating device in the grayscale shared data restoring apparatus as described above will be described as processing 5, processing 6, processing 7-1 and processing 7-2. .

(Process 5) The gradation shared data extracting unit 106 (see Fig. 10) extracts the gradation shared data generated by the gradation sharing data generating apparatus and expands it to the expansion buffer 107.

(Process 6) The gradation number selection section 108 starts the first gradation data restoration section 109 when the requested gradation count is two gradations, and activates the second gradation data restoration section 110 when the requested gradation count is three gradations. (One of the following (Process 7-1) and (Process 7-2) is selected depending on whether the requested number of gradations is 2 or 3 gradations).

FIG. 18A is a diagram showing a conversion table when the gradation value of gradation shared data is converted into the gradation value of two gradation data by the first gradation data restoration unit 109, and FIG. A diagram showing a conversion table when the second grayscale data restoration unit 110 converts the grayscale values of the grayscale shared data into grayscale values of the three grayscale data. Conversion can be done). Also,

(Process 7-1) If the requested tone number is two tone numbers, the first tone data restoration unit 109 extracts a tone value of the tone sharing data for each pixel developed in the expansion buffer 107, and this tone value On the basis of the conversion table shown in Fig. 18A, the tone values of the two tone data are obtained.

(Process 7-2) If the requested number of gradations is three gradations, the second gradation data restoring unit 110 extracts the gradation value of the gradation shared data for each pixel developed in the expansion buffer 107, and with respect to the gradation value. The gradation value in the three gradation data is obtained by applying the conversion table shown in Fig. 18B.

Fig. 19 is a diagram showing the alphabet " A " using two-tone data generated from grayscale shared data by (process 7-1), and Fig. 20 shows three generated from grayscale shared data by (process 7-2). It is a figure which shows the alphabet "A" by gradation data.

As described above, in the gradation shared data generating apparatus of the gradation shared data processing system, the gradation value of the two gradation data (1 bit) and the gradation value of the three gradation data (2 bit) are calculated from the outline data, Grayscale shared data (2 bits) is generated without increasing. In the gradation shared data restoring apparatus, the same data as the two gradation data and the three gradation data obtained by the gradation sharing data generating apparatus are restored from the gradation sharing data without causing deterioration of quality.

The gray scale shared data processing system including the gray scale shared data generating apparatus and the gray scale shared data restoring apparatus can be used in the satellite broadcasting system as shown in FIG.

21 is a diagram showing the configuration of a satellite broadcasting system using the present gray scale shared data processing system. FIG. 22 is a diagram showing a first configuration example of the gray scale shared data stored in the set top box (STB) 503 of the satellite broadcasting system, and FIG. 23 is a second diagram of the gray scale shared data stored in the STB 503. FIG. 24 is a diagram illustrating a configuration example, and FIG. 24 is a diagram illustrating a third configuration example of the gray scale shared data stored in the STB 503.

This satellite broadcasting system includes a broadcasting station 501, a satellite 502, an STB 503, and a television 504.

The broadcasting station 501 transmits image information, audio information, text information, and the like to the STB 503 through the satellite 502. The STB 503 receives these information to decode the video information, the audio information, and the text information, and reproduces the video and the audio on the television 504 to display the text. Here, the STB 503 for restoring the grayscale shared data in accordance with the character information is associated with the grayscale shared data decoding apparatus (see FIG. 10) described above, and the STB used to generate and store the grayscale shared data in the STB 503. The apparatus at the time of manufacture of 503 can be matched with the above-mentioned gray scale shared data generating apparatus.

In the satellite broadcasting system, characters are displayed on the basis of the reception of the character part (character code) from the broadcasting station 501, so that the STB 503 shares the gray levels as described above for the plurality of characters (or figures). The data is stored in a configuration as shown in Figs. 22, 23, and 24 with a plurality of additional information (the gradation shared data is displayed only when a display is performed for a specific character such as foreign characters). It is possible to transmit to the STB 503 from the 501. The gradation shared data extracting unit 106 shown in Fig. 10 has a later expansion buffer ( 107), and processing for the tone number selection unit 108).

As shown in Fig. 22, the STB 503 has tone sharing data for the first letter (e.g. "A"), tone sharing data for the second letter (e.g. "B"), and the third. Tone-sharing data for a letter (for example, "C"); Are stored in order (e.g., all letters of the alphabet are grouped). In the STB 503, necessary data are selected from the gradation shared data corresponding to the plurality of characters stored in accordance with the character specification by reception of the character code from the broadcasting station 501, for display on the television 504. The process is performed.

As shown in FIG. 23, index data can be added to gradation shared data for a plurality of characters. The index data includes a character code and a pointer showing the position of the storage unit in which the tone sharing data corresponding to the character code is stored, and the tone sharing corresponding to the character for which display from the storage unit is requested by the index data. Processing such as data extraction can be performed quickly.

As shown in Fig. 24, additional information including the data length of the grayscale shared data, the number of grayscales included, the number of grayscales, and the like can be added to the grayscale shared data for each character. By this additional information, various processes including the above process can be performed quickly, and the gradation shared data restoration apparatus can be simplified.

These data recording media can be distributed by recording the data including gray level shared data and additional information thereon on a data recording media such as a floppy disk or an optical disk.

In the satellite broadcasting system using the grayscale shared data as described above, the display capability (how many colors can be displayed) of the STB 503 (unknown by the broadcasting station 501) and the contents of the video (currently Depending on how many colors are used, the palette for displaying characters can be assigned to the palette while selecting the number of gray scales that can be represented by the data from the grayscale shared data (font data) stored by the STB 503. have.

In the grayscale shared data processing system of the above embodiment, it is assumed that two-bit grayscale shared data is generated from two grayscale data (one bit of data) and three grayscale data (two bits of data). Generating 4-bit gradation shared data from 3-bit data) and 10-gradation data (4-bit data), 2-gradation data (1-bit data), 3-gradation data (2-bit data), and 5-gradation Three-bit grayscale shared data can be generated from the data (three-bit data). That is, more generalized, the maximum number of gray levels q _α (α = 1, 2, ..., p is of the type p (p is an integer of 2 or more), m is an integer of 2 or more, and q _α is 2 ≦ q ₁ <q Maximum gray level n (n is q _p n ≦ ₂ ) from gray level data having ₂ <… <q _p , 2 ^m-1 <q _p <2 ^m <q ₁ + q ₂ +… + q _p grayscale shared data having an integer satisfying ^m ) can be generated.

Further, in the gradation sharing data generating apparatus of the gradation sharing data processing system of the above embodiment, the gradation data (the 2 gradation data and the 3 gradation data described above) which are the basis of the gradation sharing data are generated from the outline data, but the size required when generating In this case, the grayscale sharing data can be generated not from the outline data but from the stored grayscale data itself according to the condition, etc. In this case, the outline information holding unit 101 (see Fig. 10) and the outline information are generated. The enlargement / decrease section 102 and the basic gradation value calculation section 103 are unnecessary, and instead, a gradation data extracting section for extracting gradation data which is the basis of the gradation sharing data to be generated from the storage section is added.

In addition, in the gradation shared data generating device, the threshold values (TH2, TH31, and TH32 described above) used for generating two gradation data and three gradation data from the basic gradation value data in the gradation sharing data generation unit 105 are fixed. These thresholds can be changed as required by the user or the program. Accordingly, when information such as display characteristics of the display device having the display unit 5 on the side of the gradation shared data restoration device is predetermined, it is possible to generate gradation shared data capable of maximizing the capability of the display device based on this information. It becomes possible.

In addition, although the grayscale shared data generation unit 105 of the grayscale shared data generation device obtains the grayscale shared data based on the basic grayscale values obtained by the basic grayscale value calculating unit 103, the outline information expanding / decreasing unit 102 It is also possible to directly generate grayscale shared data from the obtained contour information after enlargement and reduction by chemical calculation processing using integration. As a result, the basic gradation value calculator 103 becomes unnecessary, and the apparatus can be simplified.

In addition, the gradation data selection unit 108 of the gradation shared data restoring apparatus does not include the designated gradation number determination unit for determining whether the gradation number requested from the outside is included in the gradation sharing data, and the requested gradation number is not included in the gradation sharing data. If not, an error processing unit for notifying the outside that data of the required tone number cannot be generated can be added. As a result, the stability of the processing in the gradation shared data restoration apparatus can be improved.

In addition, the gradation data selection unit 108 of the gradation shared data restoring apparatus does not include the designated gradation number determination unit for determining whether the gradation number requested from the outside is included in the gradation sharing data, and the requested gradation number is not included in the gradation sharing data. If not, among the gradation numbers that can be generated from the gradation sharing data, an optimal gradation number calculating section for obtaining the gradation number closest to the required gradation number and notifying the gradation number selection unit 108 can be added. As a result, even if the requested number of gradations is not included in the gradation sharing data, the display can be displayed on the display section 5, thereby improving the stability of the processing in the gradation sharing data restoration apparatus. In this case, it is possible to simplify the configuration of the optimum gradation number calculating section by adding information (e.g., all gradations included in the gradation sharing data) to the gradation sharing data to easily obtain the optimal gradation number from the gradation number calculating section. have.

Next, a grayscale shared data processing system as a second embodiment of the present invention will be described.

Fig. 25 is a block diagram for explaining the configuration of the gradation shared data processing system of the second embodiment of the present invention. The gradation sharing data processing system of the second embodiment of the present invention includes a gradation sharing data generating device and a gradation sharing data restoration device like the gradation sharing data processing system of the first embodiment. In the gradation sharing data processing system of this second embodiment, only the gradation sharing data generating device is different from the gradation sharing data generating device of the gradation sharing data processing system of the first embodiment, which will be described below. The details of the configuration, operation, and the like of the gradation shared data generating apparatus other than those described below shall be the same as the gradation sharing data generating apparatus of the gradation sharing data processing system of the first embodiment).

The gradation shared data generating apparatus includes an outline information holding unit 2101, a stroke information holding unit 2102, a first outline information scaling unit 2103, a first tone value calculating unit 2104, and a second outline information enlargement and reduction. A unit 2105, a second gray scale value calculator 2106, and a gray scale shared data generation unit 2107 are included.

The outline information holding unit 2101 is similar to the outline information holding unit 101 of the gradation sharing data generating apparatus of the gradation sharing data processing system of the first embodiment, and each character (or figure) from the outline data to be generated. The contour information indicated as a set of points representing the characteristic of the contour on the predetermined coordinates is extracted and held in correspondence with the &quot;

The stroke information holding unit 2102 holds stroke information based on the outline information which is the object of generation of the gradation shared data drawn out and held by the outline information holding unit 2101. The stroke information is information used to adjust the stroke width after expansion and reduction, and is generally referred to as a hint.

26 (a) and 26 (b) show the outline information of the kanji "Th" which is the object to generate the tone sharing data in this tone sharing data generating apparatus, and FIG. Is a diagram showing stroke information. Here, "Th" is shown in the Gothic style, and the outline information showing this is represented by a set of straight lines on the coordinate of 1000 mesh. The stroke information is held as a combination of the Y coordinate values of the lower straight line and the upper straight line constituting the three horizontal strokes included in "Th", and the horizontal stroke width can be obtained as these differences. The width of the horizontal stroke 1, the horizontal stroke 2, and the horizontal stroke 3 which comprise this "three" is 70 either.

The horizontal stroke information may be held as a combination of the Y coordinate value of the lower straight line and the stroke width in addition to the above, and may be maintained as an attribute of the coordinate point added to the contour information. This horizontal stroke information is one of the stroke information, and when there is a vertical stroke, the vertical stroke information is similarly retained.

The first outline information expansion and contraction unit 2103 corresponds to the first gradation number (here, two gradations) expressed in the gradation shared data together with the first gradation value calculation unit 2104 shown next, On the basis of the stroke information held in the information holding unit 2102, the outline information held in the contour information holding unit 2101 is enlarged and reduced in accordance with the requested request size.

The first tone value calculator 2104 calculates a tone value for the first tone number of each pixel based on the outline information enlarged and reduced by the first outline information enlargement / reduction unit 2103.

The second outline information expansion and contraction unit 2105 corresponds to the second tone number (here, three tone levels) expressed in the tone sharing data together with the second tone value calculation unit 2106 shown next, On the basis of the stroke information held in the information holding unit 2102, the outline information held in the contour information holding unit 2101 is enlarged and reduced in accordance with the requested request size.

The second tone value calculator 2106 calculates a tone value for the second tone number for each pixel based on the outline information enlarged and reduced by the second outline information enlargement and reduction unit 2105.

The grayscale shared data generation unit 2107 is configured by the grayscale value for grayscale data of the first grayscale number for each pixel calculated by the first grayscale value calculator 2104 and the second grayscale value calculator 2106. The grayscale shared data is generated by obtaining the grayscale value of the grayscale shared data using the grayscale value of the grayscale data of the second grayscale number for each pixel.

The order of processing in such a gradation shared data generating apparatus will be described as (process 1) to (process 7). As in the gradation shared data generating apparatus of the first gradation shared data processing system, it is assumed that two gradation data is treated as the first gradation data and three gradation data as the second gradation data. In addition, a gray value of 1 for the foreground color and 0 for a background color is assigned to the gray value of the two-tone data for each pixel, and two for the foreground color, 1 for the middle color, and one for the background color for the gray-level value of the three-tone data. It is assumed that 0 is assigned (hereinafter, the processing for the kanji "三" is exemplified, but the present invention can be similarly applied to hiragana, katakana, alphabets, characters representing other languages, and figures other than these). .

(Process 1) Initially, the outline information holding unit 2101 (see Fig. 25) draws out and holds outline information on the requested character from the storage unit storing the outline data. Here, the outline information shown in Fig. 20B is obtained from the outline data and held.

(Process 2) The stroke information holding unit 2102 draws out and holds the stroke information for the requested character from the storage unit (the stroke information is stored in the storage unit in advance). Here, the stroke information shown in FIG. 26C is obtained and maintained.

(Process 3) The first contour information expansion and contraction section 2103 uses the stroke information held by the stroke information retention section 2102 to maintain the contour information held by the contour information retention section 2101, which is a 10 × 10 request size. (Enlargement) Reduces to fit the pixel and two gradations (the first outline information enlargement / reduction section 2103 can enlarge the outline information if necessary, but reduces it here).

(Process 3) in this first contour information expansion and contraction unit 2103 will be described in more detail using a flowchart.

FIG. 27 is a flowchart showing the procedure of the processing in the first contour information expansion and contraction section 2103 (the same is the same as the processing in the second contour information expansion and contraction section 2105 as described later). The processing here can be broadly divided into horizontal stroke enlargement and reduction processing and outline information expansion and reduction processing.

In the horizontal stroke enlargement and reduction processing, first, it is determined whether there is unprocessed horizontal stroke information (corresponding to horizontal stroke 1 to horizontal stroke 3 of "three" shown in Fig. 26C) (S41). If there is unprocessed horizontal stroke information (YES in S41), this unprocessed horizontal stroke information is taken out (S42).

Here, horizontal stroke information is constructed by correlating (L, U) with respect to one of the horizontal strokes, using the Y coordinate value of the lower straight line as L and the Y coordinate of the upper straight line. Regarding "Th" shown in FIG. 26A, the stroke information 155, 225, 475, 545 for three horizontal strokes 1 to 3 horizontal strokes as shown in FIG. 780, 850 are drawn out in turn.

Subsequently, the horizontal stroke width Worg is obtained from the following equation 7 with respect to the extracted horizontal stroke information (S43). Regarding "Th", the stroke widths of the three horizontal strokes are either 70.

The horizontal stroke width thus obtained is enlarged and reduced in accordance with the required size (S44). This enlargement and reduction is performed so as to be suitable for generation of two tone data. In the two-gradation data, the gradation value of each pixel is either 1 or 0, so that the gradation value can be determined while preventing the stroke unevenness due to rounding error by setting the stroke width after enlargement and reduction in pixel units. Such a process is called a hint process, and is generally used in the case of generating two tone data from outline data showing characters. Here, the stroke width W2 after the enlargement and reduction is obtained by the following equation (8).

Where Np is the number of pixels of the required size, Nsp is the number of submeshes, EM is the number of meshes of the original contour information, and trunc (X) is a function for rounding off the value of the argument (X). In this grayscale shared data generating device, Np is 10, Nsp is 4, and EM is 1000. According to the above expression (8), the stroke widths after the enlargement and reduction of the three horizontal strokes for "three" are all four subpixels, that is, one pixel.

Next, the Y coordinate value of the horizontal stroke lower straight line is enlarged and reduced (S45). Here, similarly to the case where the stroke width is enlarged and reduced, the enlargement and reduction is performed so as to be suitable for the generation of the two tone data. By performing the enlargement and reduction so that the coordinate value after the enlargement and reduction becomes the pixel boundary, it is possible to minimize the influence of rounding error that occurs when obtaining the tone value for the three tone data. Here, the Y coordinate value L2 of the lower straight line of the horizontal stroke after expansion and contraction is obtained by the following equation (9).

Thereafter, the strike width W2 after the enlargement and reduction obtained as described above and the Y coordinate value L2 of the lower straight line of the horizontal stroke are used, and the Y coordinate value U2 of the upper straight line of the horizontal stroke is calculated by the equation (10). It becomes (S46).

Here, the Y coordinate value of the lower straight line of the horizontal stroke is enlarged and reduced and then used to obtain the Y coordinate value of the upper straight line. However, the Y coordinate value of the upper straight line of the horizontal stroke is enlarged and reduced. We can get Y coordinate value. In this case, the Y coordinate value of the upper straight line of the horizontal stroke after the enlargement and reduction is obtained by the following equation (11), and the Y coordinate value of the lower straight line is obtained by the following equation (12).

By the above-described horizontal stroke enlargement and reduction processing, horizontal stroke information after enlargement and reduction suitable for generating three tone data can be obtained. The stroke information after (expansion) reduction for the three horizontal strokes of "three" is (8, 12), (20, 24), (32, 36).

When the processing for all the horizontal stroke information is finished as described above (NO in S41), the horizontal stroke information after the enlargement and reduction is used as the outline information enlargement and reduction process, and the outline information is enlarged and reduced.

In the contour information enlargement and reduction processing, it is first determined whether there is unprocessed contour information (corresponding to contours 1 to 3 of "Three" shown in Fig. 26B) (S47). If there is unprocessed outline information (YES in S47), this unprocessed outline information is taken out (S48). Regarding "3", outlines 1 to 3 as shown in FIG. 26C are sequentially drawn out as the object of processing.

Subsequently, the Y coordinate value Yorg is drawn out from the extracted contour information (S49). The Y coordinate value Yorg is enlarged and reduced as follows, and the Y coordinate value Y2 after the enlargement and reduction is obtained (S50). . When Y2 after the enlargement and reduction is obtained for all the contour information as described below (No in S47), this processing is terminated.

When the Y coordinate value Yorg is equal to the Y coordinate value U of the upper straight line of the horizontal stroke of the original 100 mesh or the Y coordinate value L of the lower straight line, the Y coordinate value Y2 after the enlargement and reduction is It becomes the Y coordinate value U2 of the upper straight line of the horizontal stroke after expansion reduction by the horizontal stroke enlargement reduction process, or the Y coordinate value L2 of the lower straight line.

If the Y coordinate value Yorg is not equal to either the Y coordinate value U of the upper straight line of the horizontal stroke of the original 1000 mesh or the Y coordinate value L of the lower straight line, Y2) is obtained as a value obtained by linearly interpolating between the Y coordinate value of the upper straight line of each horizontal stroke and the Y coordinate value of the lower straight line.

In the gradation shared data generating device, the Y coordinate value Y2 after the enlargement and reduction is obtained from the Y coordinate value Yorg by the following equations (13) to (27).

By the above, the outline information on the coordinates of 1000 mesh is (expanded) reduced to data on 40x40 subpixels suitable for generating two-gradation data.

Although only coordinate values on the upper straight line and the lower straight line of the horizontal stroke exist here, the Y coordinate value is also used for the outline data including the coordinate values representing the straight line or the curve other than the stroke by using Equations 13 to 27 above. By correcting (Yorg) to the Y coordinate value (Y2), appropriately corrected data can be obtained (scaling down so that the position of any two data in the Y direction does not reverse before and after zooming in and out. Can be done).

In addition, since there is no vertical stroke here, appropriate data can be obtained by expanding and contracting all the X coordinate values by the following equation (28).

In the case of expanding and reducing the contour information including the vertical stroke, in the same manner as described above, first, the X coordinate value for determining the position of the vertical stroke is enlarged and reduced to suit the number of gray levels of the gray scale data, and then X for determining the position of the vertical stroke. Proper data can be obtained by linearly interpolating between coordinate values to enlarge and reduce other values (enlarging or reducing so that the position of any two data in the X direction does not reverse before or after expansion or reduction). Can be done).

28A, 28B, and 28C show contour information and strokes shown in FIGS. 26A, 26B, and 3C to be suitable for generating two tone data in the same manner as described above. FIG. 29 is a diagram showing data after enlarged and reduced information, and FIG. 29 is a diagram showing outline information of FIG. 28B deployed on a submesh.

In FIG. 28A, the solid line shows the outline obtained by performing the hint process as mentioned above, and the dashed-dotted line shows the outline when simple enlargement reduction is performed without performing the hint process mentioned above. .

According to Fig. 29, since all coordinate values that characterize the outline of "three" are on the pixel boundary, it can be seen that these coordinate values after reduction are suitable for generating two tone data.

(Process 4) The first tone value calculator 2104 calculates the tone value of the two tone data for each pixel from the outline information after the enlargement and reduction obtained by the first outline information enlargement and reduction unit 2103. Since the calculation of the gradation value is the same as the processing of the gradation sharing data generating apparatus of the gradation sharing data processing system of the first embodiment (process as shown in S21 to S25 of FIG. 15 in the gradation sharing data generating section 105). The description is not repeated here.

FIG. 30 is a diagram showing the gray scale values of the two gray scale data for each pixel obtained from the enlarged and reduced outline information of "three" in the first gray scale value calculating section 2104. FIG. The gradation value 1 is generated according to the outline of "3" as shown in FIG.

(Process 5) The second contour information expansion and contraction section 2105 uses the stroke information held by the stroke information retention section 2102 to maintain the contour information held by the contour information retention section 2101. (Enlarge) the image to fit the three gradations (the second outline information enlargement / reduction section 2105 can enlarge the outline information as needed, similarly to the first outline information enlargement / reduction section 2103, Do).

The procedure of enlarging / decreasing the Y coordinate is the same as the procedure of enlarging and contracting for generating two-gradation data in the first outline information enlarging / reducing unit 2103 described using the flowchart shown in Fig. 27 in (Process 3). Since the second outline information enlargement / reduction section 2105 performs enlargement and contraction so as to be suitable for generating three tone data, the calculation formula for enlargement and reduction is different. Each of the equations (8) through (27) used in the first contour information expansion and contraction unit 2103 corresponds to the following equations (29) through (48) respectively used in the second contour information expansion and contraction unit 2105.

Where W3 is the stroke width after scaling to fit the three-tone data, L3 is the coordinate value of the lower straight line of the horizontal stroke after scaling to fit the three-tone data, and U3 is scaled to fit the three-tone data This is the coordinate value of the upper straight line of the horizontal stroke after.

31A, 31B, and 31C show contour information and strokes shown in FIGS. 26A, 26B, and 3C so as to be suitable for generating three tone data as described above. FIG. 32 is a diagram showing data after enlarged and reduced information, and FIG. 32 is a diagram showing outline information of FIG. 31B developed on a submesh.

According to FIG. 32, since all the coordinate values characterizing the outline of "3" are on the subpixel boundary (but not on the pixel boundary), it can be seen that these coordinate values after the reduction are suitable for generating three tone data. (If the coordinates that characterize the outline of "Three" are all on the pixel boundary, you do not need to use intermediate colors.)

(Process 6) The second tone value calculator 2106 calculates the tone value of the three tone data for each pixel from the enlarged and reduced outline information obtained by the second outline information enlargement / reduction unit 2105. The calculation of the gray scale value is similar to the processing of the gray scale shared data generating apparatus of the gray scale shared data processing system of the first embodiment, similarly to the first gray scale value calculating unit 2104.

FIG. 33 is a diagram showing the gradation value of three gradation data for each pixel obtained from the enlarged and reduced contour information of "three" in FIG. As shown in Fig. 33, the gradation value 1 is generated in accordance with the outline of "three" (compared to the gradation value of the two-gradation data shown in Fig. 30, and the position of the lowest horizontal stroke is shifted by one pixel downward). I can see that).

(Process 7) The gradation shared data generation unit 2107 calculates the gradation value of the two gradation data for each pixel calculated by the first gradation value calculation unit 2104 and the angle calculated by the third gradation value calculation unit 2106. The gradation value of the gradation shared data is obtained from the matrix table (similar to the gradation sharing data processing system of the first embodiment) shown in Fig. 16 using the gradation value of the gradation data for the pixel.

Fig. 34 is a diagram showing the gradation value of the gradation shared data for &quot; three &quot; generated by the gradation shared data generation unit 2107.

When the gray scale value (see FIG. 30) of the two-tone data for each pixel is compared with the gray value of the three-tone data (see FIG. 33), only the position of the lowest horizontal stroke of "three" is changed in the vertical direction for one pixel. have. As a result, the gray scale value 2 of the gray scale shared data is generated corresponding to the other two horizontal strokes, while the gray scale value 1 of the gray scale shared data is generated corresponding to the lowest horizontal stroke.

As described above, in the grayscale shared data generating apparatus, the grayscale shared data is generated without the increase of the data amount as a hint process is performed. The grayscale data restored from the grayscale shared data generated in this manner is of good quality, and the grayscale shared data generating apparatus can be said to be suitable for generation of data requiring particularly high fidelity for the expression of its shape, such as character data. .

Subsequently, a modification of the gradation sharing data generating apparatus of the gradation sharing data processing system of the second embodiment will be described. As described above, in the gradation sharing data generating system of the gradation sharing data processing system of the second embodiment, the gradation sharing data generation of the gradation sharing data processing system of the first embodiment in order to faithfully reproduce the shape shown by the original outline information as possible. A simple enlargement and reduction as in the apparatus is not performed, but a hint process suitable for the tone data is performed for each tone data, and the enlargement and reduction is performed.

Although the quality of the grayscale data generated by the hint process is improved, there is a possibility that pixel shift occurs at the position of the stroke between the grayscale data of different gray scale numbers. As mentioned above, the "three" is compared with the gray scale value (see FIG. 30) of the two-tone data and the gray scale value (see FIG. 33) of the three-tone data as described above. .

When two-tone data is generated from such grayscale shared data using the grayscale shared data restoration apparatus according to the rule shown in Fig. 18A, the lowest horizontal stroke is extinguished and is not read as &quot; three &quot;. Fig. 35 is a diagram showing three tone data for &quot; three &quot; restored from the tone sharing data as described above by the tone sharing data restoration apparatus of the tone sharing data processing system.

In order to avoid such a problem, in the gradation sharing data generating apparatus of the present modification, a stroke adjusting unit for adjusting the position of the stroke is added, and the first contour information zooming unit 2103 (see FIG. 25) and the second contour information zooming unit ( 2105), the stroke information is provided so that the positional shift of the stroke does not occur.

Hereinafter, the stroke adjustment unit of the gradation shared data generating device of this modification will be described. 36 is a flowchart showing a processing procedure for each horizontal stroke of the two-tone data using the stroke adjustment unit of the tone-sharing data generating device of this modification.

In this case, when the stroke is misaligned, the horizontal stroke information that is enlarged and reduced to fit two gray scales is corrected to the horizontal stroke information that is scaled up and down to fit three gray scales. The stroke information can be corrected in accordance with the horizontal stroke information enlarged and reduced so as to suit two gradations.

In the process of adjusting the stroke, the horizontal stroke width W2 and Y coordinate value L2 of the lower straight line, which are enlarged and reduced so as to be suitable for two gray scales, are first obtained in the same manner as the above-described (process 3) (see FIG. 27). (S51), similarly to the above-described (Process 5) (refer to FIG. 27), the horizontal stroke width W3 enlarged and reduced to fit the three gradations and the Y coordinate value L3 of the lower straight line are obtained (S52).

The Y coordinate value L2 of the lower straight line enlarged and reduced to fit the two gradations obtained in this way is the position with the Y coordinate value L3 of the lower straight line enlarged and reduced to fit the three gradations for the same stroke as follows. The position is corrected in accordance with the relationship, and the position of the enlarged and reduced stroke is adjusted to suit two gradations. Next, in FIG. 37A, FIG. 38A, and FIG. 39A, thick lines show pixel boundaries, and thin lines show subpixel boundaries. Here, the horizontal stroke widths W2 and W3 are equal to one pixel, but the above-described case can be similarly described.

In addition, the Y coordinate value L2 is located at the pixel boundary because the enlargement reduction is performed for two gradations, and the Y coordinate value L3 is positioned at the subpixel boundary because the enlargement reduction is performed for the three gradations. The Y coordinate values L2 and L3 are assumed to be included in the pixels and subpixels that make them a lower boundary when they are on the pixel boundary and the subpixel boundary.

FIG. 37A shows positions of four Y coordinate values L2 and L3 assumed when the Y coordinate values L2 and L3 are included in the same pixel, and FIG. 37B. In this case, the grayscale value of the two-tone data for the target pixel according to the position of the Y-coordinate value L2, the Y-coordinate value L3, the grayscale value of the three-tone data, and the grayscale value of the grayscale shared data generated therefrom The figure is shown. (The gradation value of the gradation shared data is obtained from the gradation value of the 2 gradation data and the gradation value of the 3 gradation data according to the matrix table shown in Fig. 16, as described above. In accordance with the conversion tables shown in Figs. 18A and 18B, the gradation values of the two gradation data and the gradation values of the three gradation data are restored).

Referring to FIG. 37B, when the Y coordinate value L2 and the Y coordinate value L3 are included in the same pixel, the grayscale value of the grayscale shared data is 0 even though the grayscale value of the two grayscale data is 1. In this case, it is understood that the horizontal stroke is not restored when the two-tone data is restored from the grayscale shared data generated only when the difference between the Y coordinate value L2 and the Y coordinate value L3 becomes three subpixels. .

In accordance with these, the following processing is performed in the stroke adjusting unit (following S52 in FIG. 36). It is determined whether or not the Y coordinate value L2 and the Y coordinate value L3 are included in the same pixel for each of the enlarged and reduced horizontal strokes (S53). If they are included in the same pixel (YES at S53), if the difference between L2 and L3 is 3 or more (S54), if the difference between L2 and L3 is 3 or more (YES at S54), 4 is added to L2 (S55), so that L2 is The horizontal stroke representing the Y-coordinate value of the lower straight line is moved upward for four subpixels, that is, one pixel, and then the processing advances to S59. If the difference between L2 and L3 is 3 or more (NO in S54), the processing proceeds directly to S59.

38A illustrates a Y coordinate value L3 with respect to a Y coordinate value L2 when a pixel including the Y coordinate value L2 is in contact with a lower side of the pixel including the Y coordinate value L3. Fig. 38 (b) shows the gradation value of the two-tone data for the target pixel according to the position of the Y coordinate value L2 and Y coordinate value L3 in this case, 3 It is a figure which shows the gradation value of gradation data and the gradation value of the gradation shared data produced | generated from them.

Referring to FIG. 38B, when the pixel including the Y coordinate value L2 is in contact with the lower side of the pixel including the Y coordinate value L3, the gray scale value of the two gray scale data is always 1, Then, it is understood that the horizontal stroke is not restored when the gray scale value of the gray scale shared data becomes O and the two gray scale data are restored from the generated gray scale shared data.

In accordance with these, the following processing is performed in the stroke adjustment unit. If the Y coordinate value L2 and the Y coordinate value L3 are not included in the same pixel (NO in S53 of FIG. 36), it is determined whether or not L3 is included in the pixel below L2 (S56). If L3 is not included below L2, i.e. in the case described above (NO in S56), 4 is added to L2 (S55), and the horizontal stroke in which L2 shows the Y coordinate value of the lower straight line is 4 subpixels, that is, The image is moved upward by one pixel, and the process proceeds to S59.

FIG. 39A shows the Y coordinate value L3 + with respect to the Y coordinate value L2 when the pixel including the Y coordinate value L2 is in contact with the upper side of the pixel including the Y coordinate value L3. W3) shows four types of positions, and FIG. 39B shows the gradation values of the two-tone data for the target pixel according to the positions of the Y coordinate value L2 and the Y coordinate value L3 in this case. And gradation values of the gradation data of the gradation shared data generated therefrom. If the pixel including the Y coordinate value L2 is in contact with the upper side of the pixel including the Y coordinate value L3, the Y coordinate value L3 + of the upper straight line of the horizontal stroke enlarged and reduced to fit the three gray scales W3) affects the gradation value of the target pixel including L2.

Referring to FIG. 39B, in the case where the pixel including the Y coordinate value L2 is in contact with the upper side of the pixel including the Y coordinate value L3, the gray scale value of the two gray scale data becomes 1, For example, the gray scale value of the shared grayscale data becomes 0 is the Y coordinate value (L3 + W3) of the upper straight line of the horizontal stroke enlarged and reduced to fit the three gray scales, and the lower scale scaled to fit the two gray scales for the same horizontal stroke. It can be seen that the difference between the Y coordinate value L2 of the straight line is one subpixel or less. When restoring the two-tone data from the grayscale shared data generated at this time, the horizontal stroke is not restored.

In accordance with these, the following processing is performed in the stroke adjustment unit. If L3 is included below L2, i.e., in the case described above (YES in S56 in Fig. 36), it is determined whether the difference between L3 + W3 and L2 is 1 or less (S57), and the difference between L3 + W3 and L2 is 1; If less than (YES in S57), 4 is subtracted from L2 (S58), and the horizontal stroke in which L2 shows the Y coordinate value of the lower straight line is shifted downward by 4 subpixels, that is, 1 pixel, and then to S59. Processing proceeds. If the difference between L3 + W3 and L2 becomes 1 or less (NO in S57), the processing proceeds directly to S59.

As described above, when the Y coordinate value L2 causes a position shift with respect to the Y coordinate value L3, the Y coordinate value L2 is corrected (processing proceeds from S54, S55, S57, and S58). The Y coordinate value of the upper straight line of the horizontal stroke enlarged and reduced to fit the gray scale is obtained (S59), and the Y coordinate value of the lower straight line of the horizontal stroke enlarged and reduced to fit the three gray scales is obtained (S60).

In fact, the horizontal strokes 1 (155, 225) (see Fig. 26 (c)) constituting "three" are (zoom in) to the horizontal strokes 1 (8, 12) (see Fig. 28), and two tone data and 3 In the grayscale data, the position shift occurred in the stroke. However, the position shift is corrected (expanded) to the horizontal stroke 1 (4, 8) by the processing in the stroke adjusting unit as described above. By using the stroke information after the enlargement and reduction, the outline information can be enlarged and reduced to generate grayscale shared data capable of restoring the two-tone data without compromising quality.

As described above, in the gradation sharing data generating apparatus, hinting processing is performed, and the stroke to be hinted as necessary is corrected, thereby generating gradation sharing data that does not increase the amount of data.

Next, a grayscale shared data processing system as a third embodiment of the present invention will be described.

40 is a block diagram for explaining the configuration of a gradation shared data processing system according to a third embodiment of the present invention. The gradation sharing data processing system of the third embodiment of the present invention, like the gradation sharing data processing system of the first embodiment, includes a gradation sharing data generating device and a gradation sharing data restoration device. In the grayscale shared data processing system of this third embodiment, only the grayscale shared data restoring apparatus is different from the grayscale shared data restoring apparatus of the grayscale shared data processing system of the first embodiment, which will be described below. (The details of the configuration, operation, and the like of the gradation shared data restoration apparatus other than those described below shall be the same as the gradation shared data restoration apparatus of the gradation shared data processing system of the first embodiment).

The gradation shared data restoring apparatus includes a CLUT search section 3901, a drawing gradation number selection section 3902, a first gradation data drawing section 3904, a second gradation data drawing section 3904, and a gradation shared data extracting section 106 ), The expansion buffer 107, the first gradation data restoration unit 109, and the second gradation data restoration unit 110.

Among them, the grayscale shared data extracting unit 106, the expansion buffer 107, the first grayscale data restoring unit 109, and the second grayscale data restoring unit 110 are the grayscale shared data of the grayscale shared data processing system of the first embodiment. The restoring apparatus is the same as that of the corresponding part, and the description thereof is not repeated.

The CLUT retrieval unit 3901 determines whether the specified color exists in the color lookup table (obtained by referring to the image data from a predetermined image data input device) inputted from the outside (a table indicating the correspondence between palette numbers and actual colors). The search results are returned, and the search results are returned to the drawing tone selection unit 3902.

The drawing gradation number selection unit 3902 is the foreground and background colors (indicated from the image data of the predetermined image data input device) and the gradation (gradation) indicated from the outside for each of the gradation numbers of the gradation data stored in the gradation shared data. The CLUT search section 3401 is used to search whether or not all of the number-2) intermediate colors exist. The drawing gradation number selecting unit 3902 selectively starts the first gradation data restoring unit 109 and the second gradation data restoring unit 110 in correspondence with the gradation counts found to have all the intermediate colors as a result of this search. . In addition, the drawing gradation number selection unit 3902 is configured to correspond to the gradation data corresponding to the gradation number for the first gradation data drawing unit 3904 and the second gradation data drawing unit 3904 and the foreground color and the background color. 2) Output data representing the neutral color of the color.

The first gradation data drawing unit 3403 is the foreground color and the background color inputted from the drawing gradation number selection unit 3902 with respect to the gradation value of the first gradation data having the first gradation number obtained by the first gradation data restoration unit 109. Assign intermediate colors of and (tone-2) colors.

The second gradation data drawing unit 3904 is configured with the foreground color input from the drawing gradation number selection unit 3902 with respect to the gradation value of the second gradation data having the second gradation number obtained by the second gradation data restoration unit 110. Assign the middle color of the background color and (gradation-2) color.

The processing procedure in such a gradation shared data restoration apparatus is described below. However, in restoring the grayscale shared data, the description is omitted as the same as the grayscale shared data restoration apparatus of the grayscale shared data processing system of the first embodiment, and mainly the selection of the grayscale number in the state where the color lookup table is searched is performed. Explain. Here, the first tone data is referred to as two tone data, and the second tone data is referred to as three tone data.

41 is a diagram illustrating an example of a color lookup table. In this color lookup table, the correspondence between the palette number for 16 colors used for image display and the color represented by four values of (Y, U, V, α) is displayed.

Here, Y, U, and V are the values which normalized each element of the color specification by YUV display color to the range of 0-255. In general, in a drawing apparatus using a color lookup table, the contents of this table are instructed with respect to hardware for displaying, and subsequent color specification is performed by palette number. Here too, the foreground color, the background color, and the halftone of (Gradation-2) are designated as the palette number.

In the color lookup table shown in FIG. 41, (0, 128, 128, 0) with a palette number of 0 is transparent, (0, 128, 128, 255) with a palette number of 1 is black, and palette number 2 is attached ( 128, 128, 128, 255) represent an opaque gray with a concentration of 0.5, and a palette number 3 (255, 128, 128, 255) represents an opaque bag.

In this gradation shared data restoring apparatus, a palette number 1 (i.e. black) is used for the gradation data for the foreground color and a palette number 3 (i.e., white) for the gradation data for the background color using the color look-up table thus designated. Is said to be directed.

This CLUT searching unit 3901 has the following two functions.

(Function 1) Returns the value of YUVα for the given palette number as an input.

(Function 2) Checks whether or not the YUVα value given as an input exists in the color lookup table and returns the palette number if present.

The color lookup table can be represented by an array variable, and (function 1) can implement its function by simply returning a specified element of the array, and (function 2) by performing a linear search on the array variable.

Using the CLUT retrieval unit 3901 having such a function, the drawing gradation selection unit 3902 then processes in the order shown as (Process 1) to (Process 3).

(Process 1) First, the YUVα values of the foreground color and the background color are determined from the palette number using the CLUT search unit 3401. Hereinafter, the foreground color is (Yf, Uf, Vf, αf) and the background color is (Yg, Ug, Vg, αg).

(Process 2) Subsequently, (Process 2-1) and (Process 2-2) are repeated for the number of gray levels of the grayscale data, that is, two and three gray scales.

(Process 2-1) The halftone value of the (tone-2) color is calculated | required. When the number of gradations is G, Y, U, V, and α for the n-th intermediate color are obtained as shown in the following equations (49) to (52).

(Process 2-2) The CLUT search unit 3901 is used to search for all of the intermediate colors obtained in (Process 2-1) or not in the color lookup table.

(Process 3) Gray data restoring unit (any of the first gray data restoring unit 109 and the second gray data restoring unit 110) corresponding to grayscale data for which all the halftones are found in the color lookup table. And the palette number for each intermediate color obtained as a result of the search, and the palette number for the foreground color and the background color, together with the tone data drawing unit (the first tone data drawing unit 3403 and the second tone data drawing unit 3904). Output to)).

When a plurality of tones exist in the color look-up table by all the intermediate colors by the search for the intermediate colors, the image having the highest quality can be obtained by selecting the one having the maximum number of tones.

In fact, if the foreground color is assigned to palette number 1 and the background color is assigned to palette number 3, the above-described order is processed as follows.

First, by (process 1), the foreground color is determined as (0, 128, 128, 255), and the background color is (0, 128, 128, 255).

In (Process 2), since the number of intermediate colors is 0 for two grayscales, the color lookup table is not searched, and it is found that drawing in two grayscales is possible. Further, in (Process 2), one color is found in (Process 2-1) for three gradations, and it is determined that it is (128, 255, 255, 255). Further, in (Process 2), the CLUT search unit 3901 is used in (Process 2-2) for three gradations, and it is searched that this intermediate color is set to palette number 3.

Subsequently, in (Process 3), it is found that drawing can be performed by either of two or three gradations, so that the palette number 1 for the foreground color and palette number 3 for the background color for the second tone data drawing unit 3904. Is output, and palette number 2 for the intermediate color is output.

The second gray level restoration section 110 obtains a gray level value for the three gray level data for each pixel in the same manner as the gray level shared data restoration apparatus of the gray level shared data processing system of the first embodiment, and the second gray level data drawing section 3904. ), The background color (here palette number 3), the middle color (here palette number 2), and the foreground color (here palette number 1) correspond to each of the gradation values 0, 1, and 2 for each pixel represented by the 3 gradation data. The display unit is instructed to perform drawing.

In this order, an appropriate tone data can be selected from among a plurality of types of tone data for the foreground color, the background color and the color lookup table (given from the outside), and drawing can be performed.

As described above, in the gradation shared data restoration apparatus, an appropriate gradation number is selected from gradation shared data that does not increase the amount of data while the color lookup table specified externally is used, and gradation data having high quality is restored.

Subsequently, a modification of the gradation shared data restoration apparatus of the gradation shared data processing system of the third embodiment will be described. As described above, in the gradation sharing data restoration apparatus of the gradation sharing data processing system of the third embodiment, when searching for intermediate colors by the CLUT searching unit 3901 (see Fig. 40), the colors are compared by strictly matching values or not. In the gradation-sharing data restoration apparatus of the present modification, by searching for a color that approximates the target intermediate color, even if no color exactly matches the target intermediate color in the color lookup table, the gradation number is high. I can perform drawing.

The operation of the CLUT retrieving unit 390l that can select an approximate color of (Y, U, V, α) of the gradation shared data restoration apparatus of this modification will be described below.

The CLUT retrieval unit 3901 has an error of ± 10% in luminance Y with respect to the background color (Yb, Ub, Vb, αb) and foreground color (Yf, Uf, Vf, αf) given for the three-gradation data. The error of ± 3 degrees shall be tolerated for the chroma ring formed by U / V. At this time, the intermediate colors (Ym, Um, Vm, αm) are selected from the respective colors of the color lookup table suitable for the following (Condition 1) to (Condition 4).

(Condition 1) When αb = 0 (background color is transparent):

(Condition 2) When αf = 0:

(Condition 3) For αf = αb = 255 (both background and foreground color are neither transparent nor translucent):

(Condition 4) other than 1) to 3):

According to (Condition 1) of the colors in the color lookup table, a color with half translucency is suitable for the same color as the foreground color, and according to (Condition 2), a color with half translucency is used for the same color as the background color. According to (Condition 3), a color of the same series as the background color and the foreground color is suitable for YUV, and a transparent and non-transparent color is suitable, and according to (Condition 4), a color near the intermediate color is suitable for YUVα.

As described above, in the gradation shared data restoring apparatus of the present modification, an intermediate color used from the foreground color and the background color is approximated as required while the color lookup table specified externally is used, and appropriate gradation from the gradation shared data that does not increase the amount of data. The number is selected to restore high quality gradation data.

In addition, in the gradation shared data restoration apparatus of the present modification, (condition 1) to (condition 4) are given to approximate the intermediate color, other conditions may be used.

In addition, in the grayscale shared data restoration apparatus of this modification, the color is designated by the YUVα value in the color lookup table, but a color lookup table expressed in another color space such as RGB may be used.

In the gradation shared data restoring apparatus of this modification, the gradation data is restored from the gradation sharing data, but the selection of the gradation number for a given color lookup table is also possible in a system using a plurality of ordinary gradation data that do not share the gradation data. Applicable

Preferred embodiments of the present invention described above are disclosed for purposes of illustration, and those skilled in the art will be able to make various modifications, changes, substitutions and additions through the spirit and scope of the present invention as set forth in the appended claims.

Claims (30)

From the contour information representing the outline of a symbol including a character or a figure, a plurality of types of gray scale data for representing the symbol are shared corresponding to a predetermined number of pixels representing the gray scale, and the gray scale shared data generating device generating gray scale shared data. In P (p is an integer of 2 or more) gradation data generating means for generating gradation data of the p type maximum gradation number q _α (α = 1, 2, ..., p) from the contour information, wherein m Is an integer of 2 or more, and q _α is 2 ≦ q ₁ q ₂ .. q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . Is an integer satisfying _p + q, It comprises a tone share data generating means for generating n in number of gradations up to gray level shared data from the gradation data of the generated p type, n is the tone sharing data generating device, characterized in that an integer satisfying q _p n≤ 2 ^m . The method of claim 1, Basic gradation data generating means for generating basic gradation data representing a ratio of an area of an inner portion of the contour to each of the pixels from the contour information; And each of the p tone data generating means generates the tone data according to the maximum number of tone q _alpha from the basic tone data. The method of claim 2, Setting means for setting a threshold, And each of the p gray scale data generating means generates gray scale data according to the maximum gray number q _α using the set threshold value from the basic gray scale data. The method of claim 1, The tone sharing data generating means is the maximum tone number n for a combination of (q ₁ x q ₂ x ... x q _p ) branches for each tone obtained by each of the tone data having the maximum tone number q _α . And a gradation data having the maximum number of gradations n is generated by allocating gradations acquired by the gradation data. A plurality of types of gradation data for representing the symbol correspond to a predetermined number of pixels indicating gradation from outline information indicating the outline of a symbol including a character or a figure and stroke information indicating the position of the stroke constituting the symbol. In the gradation shared data generating device for generating gradation shared data, P (p is an integer of 2 or more) gradations for generating gradation data of the p type maximum gradation number q _α (α = 1, 2, ..., p) while performing hint processing from the outline information and the stroke information. Data generating means, wherein m is an integer of 2 or more, and q _α is 2 ≦ q ₁ q ₂ . . . q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . Is an integer satisfying _p + q, Grayscale shared data generating means for generating grayscale shared data having a maximum number of grayscale n from the p-type grayscale data, wherein n is an integer satisfying q _p n ≤ 2 ^m . . The method of claim 5, And gradation means for adjusting stroke information for generating gradation data of another (p-1) type on the basis of the stroke information for one gradation data of the p kinds to be generated. Device. A gradation shared data restoration apparatus for restoring gradation data from gradation sharing data sharing plural kinds of gradation data for representing a symbol including a character or a figure corresponding to a predetermined number of pixels indicating gradation, The grayscale shared data is generated to have a maximum grayscale number n from grayscale data of p type maximum grayscale number q _α (p is an integer of 2 or more and α = 1, 2, ..., p), and m Is an integer of 2 or more, and q _α is 2 ≦ q ₁ q ₂ .. q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . + is an integer that satisfies _p , n is an integer that satisfies q _p n ≤ 2 ^m , A maximum number of numbers selecting means for selecting the maximum number of grays, And gradation shared data restoring means for restoring gradation data which is the selected maximum gradation number from the generated gradation sharing data. The method of claim 7, wherein And the gradation shared data restoring means restores the gradation data by allocating a gradation acquired by the gradation sharing data to a gradation obtained by the gradation data of the selected maximum gradation number. The method of claim 8, Storage means for storing a p-type table that associates the gradation acquired by each of the p-type gradation data with the gradation acquired by the gradation shared data, And the gradation shared data restoring means performs the assignment using a table corresponding to the gradation data of the selected maximum gradation number among the stored p kinds of tables. The method of claim 7, wherein Judging means for judging whether or not tone data of the selected maximum tone number is included in the tone sharing data; And external notification means for notifying outside that gradation data which is the selected maximum gradation number cannot be restored when it is determined that the gradation data of the selected maximum gradation number is not included in the gradation sharing data. Shared data generator. The method of claim 7, wherein Judging means for judging whether or not tone data of the selected maximum tone number is included in the tone sharing data; And second maximum gradation number selection means for selecting a maximum gradation number having a small difference from the selected maximum gradation number when it is determined that gradation data of the selected maximum gradation number is not included in the gradation sharing data. Gradation shared data generating device. The method of claim 7, wherein And assigning means for allocating a color in a predetermined color lookup table with respect to the gradation obtained by the restored gradation data. The method of claim 7, wherein From the data specifying the foreground color and the background color among the predetermined color look-up tables, each of the intermediate colors of one or more grayscales (except the foreground and background colors) for the restored three or more grayscale data is excluded. Calculating means for calculating data, And allocating means for allocating a color included in a predetermined range from the calculated data in the color lookup table for each of the one or more gradations. A gradation data processing apparatus for processing gradation data for representing a symbol including a character or a figure corresponding to a predetermined number of pixels representing a gradation, Calculating means for calculating data specifying one or more gradations for the gradation data of three or more gradations (except the foreground color and the background color) from data specifying the foreground color and the background color in the predetermined color lookup table; And allocating means for allocating a color included in a predetermined range from the calculated data in the color lookup table for each of the one or more gradations. A gradation sharing data generation device for generating gradation sharing data by sharing plural kinds of gradation data for representing the symbol in accordance with a predetermined number of pixels indicating gradation from contour information indicating the outline of a symbol including a character or a figure. To First gradation data generating means for generating gradation data of the maximum gradation number 2 from the contour information; Second gradation data generating means for generating gradation data of the maximum gradation number 3 from the contour information; And gradation shared data generation means for generating gradation shared data of maximal gradation number 4 from the gradation data of maximal gradation number 2 and gradation data of maximal number 3. A gradation shared data restoration apparatus for restoring gradation data from gradation sharing data sharing plural kinds of gradation data for representing a symbol including a character or a figure corresponding to a predetermined number of pixels indicating gradation, The gray scale shared data is generated to have a maximum gray number 4 from gray data of the maximum gray number 2 and gray data of the maximum gray number 3, A maximum number selection means for selecting the maximum number of gray numbers 2 or the maximum number of gray numbers, and And gradation shared data restoring means for restoring gradation data which is the selected maximum gradation number from the gradation sharing data. In the gradation sharing data generation method, a plurality of types of gradation data for representing the symbol are shared from the contour information representing the outline of a symbol including a character or a figure, and the gradation sharing data is generated. In P (p is an integer of 2 or more) gradation data generation steps for generating gradation data of p type gradation number q _α (α = 1, 2, ..., p) from the contour information, wherein m Is an integer of 2 or more, and q _α is 2 ≦ q ₁ q ₂ . . . q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . Is an integer satisfying _p + q, A grayscale shared data generating step of generating grayscale shared data having a maximum number of grayscale n from the p-type grayscale data, wherein n is an integer satisfying q _p n ≤ 2 ^m . . A plurality of types of gradation data for expressing the symbol in correspondence with a predetermined number of pixels indicating gradation are shared from the contour information indicating the outline of a symbol including a character or a figure, and the stroke information indicating the stroke position constituting the symbol. In the gradation shared data generation method for generating gradation shared data, P (p is an integer of 2 or more) gradations that generate gradation data of p type maximum gradation number q _α (α = 1, 2, ..., p) while performing hint processing from the outline information and the stroke information Data generation step, wherein m is an integer of 2 or more, and q _α is 2 ≦ q ₁ q ₂ . . . q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . Is an integer satisfying _p + q, A grayscale shared data generating step of generating grayscale shared data having a maximum number of grayscale n from the p-type grayscale data, wherein n is an integer satisfying q _p n ≦ ^2m . . A gradation shared data restoration method for restoring gradation data from gradation sharing data for sharing plural kinds of gradation data for representing a symbol including a character or a figure corresponding to a predetermined number of pixels indicating gradation, The grayscale shared data is generated to have a maximum grayscale number n from grayscale data of p type maximum grayscale number q _α (p is an integer of 2 or more and α = 1, 2, ..., p), and m Is an integer of 2 or more, and q _α is 2 ≦ q ₁ q ₂ .. q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . + is an integer that satisfies _p , n is an integer that satisfies q _p n ≤ 2 ^m , A maximum number of steps for selecting the maximum number of tones, And a grayscale shared data restoring step of restoring grayscale data which is the selected maximum grayscale number from the generated grayscale shared data. A gradation data processing method for processing gradation data for representing a symbol including a character or a figure corresponding to a predetermined number of pixels representing a gradation, A calculation step of calculating data for specifying each of one or more gradation colors for gradation data of three or more gradations (excluding the foreground and background colors) from the data specifying the foreground color and the background color among the predetermined color lookup tables; , And an allocating step of allocating a color included in a predetermined range from the calculated data in the color lookup table for each of the one or more gradations. In the gradation sharing data generation method, a plurality of types of gradation data for representing the symbol are shared from the contour information representing the outline of a symbol including a character or a figure, and the gradation sharing data is generated. In A first gradation data generation step of generating gradation data of the maximum gradation number 2 from the contour information; A second grayscale data generating step of generating grayscale data having a maximum number of grayscales 3 from the contour information; And a grayscale shared data generation step of generating grayscale shared data of up to grayscale number 4 from grayscale data of the maximum grayscale number 2 and grayscale data of up to grayscale number 3. A gradation shared data restoration method for restoring gradation data from gradation sharing data for sharing plural kinds of gradation data for representing a symbol including a character or a figure corresponding to a predetermined number of pixels indicating gradation, The gray scale shared data is generated to have a maximum gray number 4 from gray data of the maximum gray number 2 and gray data of the maximum gray number 3, Selecting the maximum number of gray levels for selecting the maximum number of gray levels 2 or the maximum number of gray levels, and And a gradation shared data restoring step of restoring gradation data which is the selected maximum gradation number from the gradation sharing data. A plurality of types of gradation data for representing the symbol are shared from the contour information representing the outline of a symbol including a character or a figure, a gradation sharing data is generated, and a program is recorded. In a computer-readable recording medium, From the contour information, grayscale data of p type maximum grayscale number q _α (p is an integer of 2 or more and α = 1, 2, ..., p) is generated, and from the generated ptype grayscale data, Records a program that generates gradation shared data with the maximum number of gradations n, Here, m is an integer of 2 or more, and q _α is 2 ≦ q ₁ q ₂ .. q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . + is an integer satisfying q _p , and n is an integer satisfying q _p n ≤ 2 ^m . A plurality of types of gradation data for representing the symbol are shared in accordance with a predetermined number of pixels indicating the gradation from outline information indicating the outline of a symbol including a character or a figure and stroke information indicating a position of the stroke constituting the symbol. A computer-readable recording medium for generating gradation sharing data and recording a program, While performing hint processing from the outline information and the stroke information, gray scale data of p type maximum gray scale number q _α (p is an integer of 2 or more and α = 1, 2, ..., p) is generated, and From the p-type gradation data generated, a program for generating gradation shared data having a maximum gradation number n is recorded. Here, m is an integer of 2 or more, and q _α is 2 ≦ q ₁ q ₂ .. q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . + is an integer satisfying q _p , and n is an integer satisfying q _p n ≤ 2 ^m . A computer-readable recording medium for restoring grayscale data from grayscale shared data sharing a plurality of types of grayscale data for representing a symbol including a character or a figure corresponding to a predetermined number of pixels representing grayscale, and recording a program. The grayscale shared data is generated to have a maximum grayscale number n from grayscale data of p type maximum grayscale number q _α (p is an integer of 2 or more and α = 1, 2, ..., p), and m is An integer of 2 or more, q _α is 2 ≦ q ₁ q ₂ .. q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . + is an integer that satisfies _p , n is an integer that satisfies q _p n ≤ 2 ^m , And selecting a maximum number of gray levels, and recording a program for restoring the gray level data which is the selected maximum number of gray levels from the generated gray level shared data. A computer-readable recording medium for processing gradation data for representing a symbol including a character or a figure corresponding to a predetermined number of pixels representing a gradation, and recording a program. From the data specifying the foreground color and the background color in the predetermined color look-up table, data specifying each of one or more gradation colors for gradation data of three or more gradations (except foreground colors and background colors) is calculated, and the 1 And a program for allocating a color included in a predetermined range from the calculated data in the color lookup table for each of the intermediate colors of gradation or higher. A computer for sharing a plurality of types of gradation data for representing the symbol, generating gradation sharing data, and recording a program corresponding to a predetermined number of pixels indicating gradation from the contour information representing the outline of a symbol including a character or a figure. A readable recording medium, And a program for generating grayscale data having a maximum number of grayscales and grayscale data having a maximum number of grayscales from the contour information, and generating grayscale shared data having a maximum grayscale number of four from the generated two kinds of grayscale data. Record carrier. A computer-readable recording medium for recording a program for restoring grayscale data from grayscale shared data sharing a plurality of types of grayscale data for representing a symbol including a character or a figure corresponding to a predetermined number of pixels representing grayscale, The grayscale shared data is generated to have a maximum number of grayscales 4 from grayscale data having a maximum grayscale number of two and grayscale data having a maximum grayscale number of three. And selecting a maximum number of gray levels, and recording a program for restoring the gray level data which is the selected maximum number of gray levels from the generated gray level shared data. A computer-readable recording medium for sharing plural types of gradation data for representing a symbol including a character or a figure and recording gradation sharing data corresponding to a predetermined number of pixels representing gradations, The maximum number of gradations n is generated from the gradation data, which are respectively generated from the contour information representing the outline of the symbol, and are p-type maximum gradations q q _α (p is an integer of 2 or more and α = 1, 2, ..., p) Recording the grayscale shared data generated to have Here, m is an integer of 2 or more, and q _α is 2 ≦ q ₁ q ₂ .. q _p , 2 ^m-1 q _p 2 ^m q ₁ + q ₂ +. . . A recording medium, characterized in that + q _p is an integer. A computer-readable recording medium for sharing plural types of gradation data for representing a symbol including a character or a figure and recording gradation sharing data corresponding to a predetermined number of pixels representing gradations, Recording data, each of which is generated from contour information representing the outline of the symbol and which has a maximum number of tones 4 from the data of the maximum number of tones 2 and the maximum of the number of tones 3;