JPS586672A - Information compressing device for character pattern - Google Patents

Abstract

PURPOSE:To compress information on a character pattern, consisting of numbers of picture elements, to be outputted, by combining the character pattern with a segment expressed by one data on two-dimensional coordinates, one length and one direction value. CONSTITUTION:A direction pattern deciding means 4 receives binary data from a character pattern storage means 1 to check the succeeding direction of black dots from respective picture element values and peripheral picture element values of a character pattern, and regards a long succession direction as the direction value of the picture element. The direction value of each picture element is supplied to an integrating means 7, which integrates picture elements which are substantially adjacent and have substantially the same direction value, thus generating a segment which consists of numbers of picture elements. This segment is inputted to a compressed-data outputting means 8, which calculates and outputs the direction value, position, and length that the segment has. Thus, the compressibility is improved to about 1/100.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for efficiently compressing information on a character pattern represented by a two-dimensional binary pattern, and in particular, integrates the directional properties of each pixel of the character pattern. By doing so, the present invention aims to provide a device which can finally express and output the above-mentioned character pattern using a small number of segments each having one coordinate, one length, and one direction.

The present invention will be explained in detail below.

A method for compressing character patterns such as kanji patterns is already known. Examples include the one-dimensional and two-dimensional run-length methods used in facsimiles, and the block coding method that integrates the characteristics of small two-dimensional areas, but all of these methods are at best unable to handle kanji patterns. Only a fraction of the compression ratio can be obtained.

The present invention focuses on the fact that the constituent elements of a kanji pattern are mainly straight lines, and extracts the straight #' from the original pattern and describes it in terms of position, length, and direction, and the compression ratio reaches approximately □.

10. FIG. 1 is a block diagram showing an embodiment of the present invention. In the figure, character pattern storage means 1 is composed of a plurality of pixels having binary levels. When recording relatively complex characters such as kanji, it is preferable to configure the number of pixels to about 100×100, but the present invention is not limited to this number of pixels. Further, a storage device and an imaging device configured of pixels having multilevel levels are provided before the character pattern storage device 1;
Even if a device that binarizes the levels of those pixels is connected, it is included in the present invention.

The direction pattern determining means 4 reads the binary data of each pixel from the character pattern storage means, calculates the direction value of the pixel for each pixel from the value of the pixel and the values of surrounding pixels, and outputs the result. The configuration may include the direction pattern determining means 2 and the noise removing means 3 for removing pixels having isolated direction values when the direction value of a specific pixel is isolated from the direction values of its surrounding pixels. The present invention does not limit the means for removing pixels with isolated direction values; for example, a method such as removing all the direction values of pixels corresponding to the entire periphery of a character written in pencil may be used. Alternatively, a method such as taking a majority vote among the direction values of a plurality of pixels in a specific minute region and then replacing the minority direction value with the majority direction value may be used. Any means is sufficient as long as the direction value of can have a value indicating the directionality of the character pattern resulting from the values of surrounding pixels, and should not be limited by other matters. One embodiment of the direction value determining means will be described below.

First, the individual black points that make up the character pattern (for example, a pixel value of 1. may be a black point and a pixel value of 0 may be a white point, or vice versa) are vertical and horizontal.

26.6° up the right, 45° up the right, 63.4° up the right,
It is determined which of the eight directions, upper left 926.6°, upper left v45°, and upper left 63.4°, and a second
Give the direction values shown in the figure. The determination method is to measure the distance from the black spot pixel to the point where the black spot pixel stops in each of the eight directions mentioned above, and take the longest direction as the direction value of that pixel. For example, as shown in FIG. 2, when all areas within the ellipse are black points, a direction value of 2 is given to the point pixel. For the white point, the direction value is O. However, when the direction value is an odd value, the determination as to whether the black points are continuous is made as illustrated in FIG. 4. In Figure 4, the direction value is 1.
”, the direction ゛′ is only in the case of (mu) or monkey).
This indicates that the black dots are determined to be continuous at 1". If the direction value is 53", it is considered continuous if the direction value is (C) or ■). The same applies to other directions.

The integrating means 7 in FIG. 1 is supplied with the direction value of each pixel output from the direction pattern determining means 4, and integrates pixels 7... which are substantially adjacent and have substantially the same direction value. Then, a segment consisting of a plurality of pixels is created. The integrating means 7 includes a pixel integrating means 6 that integrates a set of consecutive pixels having the same direction value into a primary segment;
The configuration may include segment integration means 6 for further integrating the plurality of primary segments created by the pixel integration means 6.

An example of the above-mentioned segment integration method will be shown below, and the present invention is directed to this example. It is not limited to.

The biggest problem when character patterns are integrated and segmented is when what should originally be one segment is divided into multiple segments, as shown in FIG. Figure 6(c)
Since the horizontal line segment (direction value 8) should originally be considered as one segment, it is necessary to integrate it.

That is, the purpose is to fill area b in FIG. 5(C) with a direction value of 8. Therefore, if you extend from area a in the direction of the direction value of area a (i.e. 8), and there is a segment with the same direction value (in this case, area O) at the end of the extension, 7
Assume that there is a possibility of merging both segments. Next, if there is a possibility of integration, check whether the above extension line is a black pixel [in this case, area b is the area of black pixels in Figure 6 (m)], and If the area has continuous pixels, both segments lf are integrated.

The compressed data output means 8 in FIG. 1 calculates and outputs the segmentation obtained by integrating the pixels as described above, the direction value, position, and length of the segment. The position may be the center coordinates of the segment, or the coordinates of the starting point or end point. Furthermore, the units of these coordinates and lengths may be pixel units that constitute a character pattern, or may be units that have been subjected to rougher quantization.

As explained in detail above, the present invention is a character that outputs a character pattern represented by a large number of pixels as a combination of segments represented by one two-dimensional coordinate, one length, and one direction value. It provides a pattern information compression device, and its compression effect is extremely large.

[Brief explanation of the drawing]

Figure 2 Figure 3 JR4 map Figure 5

Claims (1)

[Scope of Claims] (1) A two-dimensional character pattern consisting of a plurality of pixels having binary levels; a pattern storage means; reading the binary data of each pixel from the character pattern storage means; direction pattern determining means for calculating and outputting a direction value of the pixel for each pixel from the value and the values of surrounding pixels of the pixel;
The direction value of each pixel output from the direction pattern determining means is supplied, and pixels that are substantially adjacent and having substantially the same direction value are integrated to create a segment, and the character pattern storage means is stored. integrating means for outputting segments If the number of segments is smaller than the number of constituent pixels, and a position on a two-dimensional plane indicating the characteristics of the segment based on the position of the pixels constituting each segment and the direction value of the segment when the segments are supplied; Pressure 2 that calculates and outputs the coordinates, direction values, and lengths of segments on a two-dimensional plane. 1. An information compression device for character patterns, comprising a compressed data output means. (2. In the description of claim (1), the direction pattern determining means reads the binary data of each pixel from the character pattern storage means, and calculates the value of the pixel and the values of surrounding pixels of the pixel. a direction value determining means for calculating the direction value of the pixel for each pixel from the pixel, and removing a pixel having an isolated direction value when the direction value of each pixel is isolated from the direction values of surrounding pixels of the pixel; A character pattern information compression device characterized in that the character pattern information compression device is configured to include a noise removing means that removes noise from the direction pattern determining means. pixel integration means that is supplied with the direction value of each output pixel and integrates all pixels that are substantially adjacent and have substantially the same direction value to create a primary segment; and a plurality of primary segments If. The comparison shows that the other segments have the same direction value, and that the other segment is located at the position where one segment extends in the direction of the direction value, and that the two segments have different direction values. 1. An information compression device for character patterns, characterized in that the device includes segment integration means for integrating both segments into one segment when the two segments are filled in a part of the character pattern.