JPS6024677A - Character separating device - Google Patents

Abstract

PURPOSE:To execute a separation to one character even if a contact is generated between characters by forecasting by a character pitch a separated position of a character group image which has generated a contact, and correcting the separating position by referring to a blank information of an adjacent other character-string image. CONSTITUTION:A scanner 1 scans optically a character-string image, converts it to an electric signal, quantizes it and writes it to a character-string image memory 2. A character lump extracting device 3 extracts successively a position, a width and a height of a character image (hereinafter called a character lump) which can be separated by a space, to each character- string unit from the memory 2, and stores them in a character lump information register 4. A character pitch detecting device 5 measures a character pitch by using an information of the register 4. A contact character lump detecting device 6 reads out successively a width of a character lump of the contents of the resister 4, compares it with the character pitch, and when it is detected that plural characters are contained in the character lump, its position, width and height are transferred to a separated position calculating device 7. The device 7 begins with the initial part of the character lump, calculates a candidate example position to be divided in the next time, calculates the upper and lower limit values of a separable section from said result and a prescribed allowable width, and executes a correction.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a character separation device that separates a character string image written on paper into individual characters, and particularly to a character separation device that separates touching characters.

A device that optically reads various groups of printed characters (hereinafter referred to as OCR)
When recognizing a series of characters, it is necessary to separate each character and send them to the character recognition unit. The information required to separate each character is the character pitch, which can be given in advance if the size of the printed matter cannot be limited. However, as has recently been the case, when OCR scans a wide range of applications such as mail and documents with unspecified character visibility, it is necessary to calculate the character pitch from the paper surface.
Such a character pitch detection method includes, for example, a character pitch detection device as disclosed in Japanese Patent Application No. 58-33068 ``Character Pitch Detection Device'' filed by the same applicant. Therefore, when separating characters that actually touch each other using the character pitch described above, if you forcibly separate them using the character pitch described above, it may not be possible to correctly separate the characters depending on the accuracy of character pitch estimation etc. The position is not determined, which may cause misreading or unreadability in the character recognition unit.

SUMMARY OF THE INVENTION Therefore, in order to solve the above-mentioned problems, it is an object of the present invention to first predict the separation position of a character group image in which contact has occurred between characters based on the character pitch, and then To provide a character separation device that can easily improve character separation accuracy even when contact occurs between characters by correcting separation positions with reference to blank information in a character string image. be.

According to the present invention, in a character separation device that scans a plurality of character string images written on a paper surface and separates them into character units, character images (hereinafter referred to as A means for sequentially extracting the position, width, and height of a character block (called a character block) for each character string unit, a means for detecting character pitch using a plurality of character blocks, and a character block containing a plurality of characters. Starting from the starting end position of the character block, the next separation position to be divided is predicted based on the previous separation position and character pitch, and a constant allowable width on the left and right is set based on the predicted separation position. Create a separable section with a space, and search within the separable section on the upper or lower adjacent character string image from the separation position. First, correct the predicted separation position based on the position where a space is detected. A character separating device is obtained, characterized in that it has means.

Hereinafter, the present invention will be explained with reference to a specific embodiment.

FIG. 1 is a diagram showing an example of a character pattern for explaining the present invention in detail. In the figure, the character block 'Mrs' surrounded by the dotted line is part of the character string image and has a width ΔvL, and the character block %'[J'' and the character block '''O8'' surrounded by the dotted line are the characters This is a part of the character string image located below the block 'Mrs'. In the figure, P is the character pitch, which may be given in advance or estimated from the character block with the paper surface. , the separation position for separating the character block 'Mrs' into -character units can be determined as follows. When it is detected that the character block 'Mrs' includes multiple characters from the relationship between the width Δv1 of the character block '''Mrs' and the character pitch P, the sum of the starting point x of the character block 'Mrs' and the character pitch P is detected. By calculating xs+P, the first separation position x'(1) is obtained.

A separable section (X'(1) - Δτ, X'+1) + having a constant allowable width Δτ based on the separation position X'(1)
Δτ) is calculated. Next, within the above-mentioned separable section in the character string image located above or below the character string image to which the character block 'Mrs' belongs, the separation position x'
When a space is detected by arching left and right from (1), the separation position X' (1) is determined by the first detected position.
Correct. In the figure, since there is a space SP between the character block 'U'' and the character block 'os', the separation position X'(1)
is corrected to the separation position X(1).

Next, the separation position x/ (2) to be divided is the separation position
It is calculated by adding the character pitch P from (1), and the separation position X' (21) is corrected in the same way.

In the figure, since the character block 'O8'' is in contact, no space is detected and the separation position x/(2) remains unchanged without being moved.

In this way, the separation position of a character block including a contact in an arbitrary character string is determined. - FIG. 2 is a logical block diagram showing a specific embodiment of the present invention. Scanning device if: 1 is written as 0 on the page] Also, a plurality of character string images are optically scanned and converted into electrical signals, and after binary quantization is performed, they are written into the character string image memory 2.

3 is a character block extraction device, and a character string image memory 2
Also, extract the position, width, and height of a character block that can be separated by a space from the character string image (hereinafter, the width and height will be referred to as the size) for each character string, Store in character block information 1/register 4. Note that the above-described character block extraction device 3 can be realized using a known technique. 5
is a character pitch detection device, which measures the character pitch P using the positions and sizes of a plurality of character blocks stored in the character block information 17 register 4. Note that the character pitch detection device 5 can use the known technology described above.

Reference numeral 6 denotes a touching character block detection device, which sequentially reads out the width of the character block which is the content of the character block information register 4 and compares it with the character pitch P calculated by the character pitch detection device 5. If it is detected, the position and size of the input character block are transferred to the separation position calculation device 7. The separation position calculation device 7 sequentially calculates the th (k = 0.1.2...) separation position fa X (
k) and the character pitch P, calculate the +1st separation position X'(k+1), which is the next candidate position for division, and calculate the separable section from the calculated separation position and the constant allowable width Δτ. Meaning, the lower limit r(k+1)−Δτ.

Calculate x'(k+1)+Δτ. In addition, the separation position X (0
) represents the beginning of the input character block. Further, the constant allowable width Δτ may be set according to the value of the character pitch P. Next, the separation position calculation device 7 sends to the separation position correction device 8 the position and height of the character string image adjacent to the upper or lower direction of the character string image including the above-mentioned separable section and the input character block. °Transfer. It is assumed that the position and height of the character string image are calculated by the above-mentioned character block extraction device from the positions and heights of a plurality of character blocks belonging to the character string image. The separation position correction device w8 is
It is composed of a projection distribution extraction device 81, a projection information register 82, and a space detection device 83. Projection distribution extraction device M81
The character string image memory 2 is scanned to determine the vertical projection distribution within the area set by the separable section transferred from the separation position calculation device 7 and the position and height of the adjacent character string image described above. , are stored in the projection information register 82.

The space detection device 83 refers to the projection information register 82 to check whether a space exists, that is, a position where the value of the projection information is 0, and if it exists, the above-mentioned separation position
The correction position where a space is first detected from '(k+1) (the correction position represents the separation position x(k+1)) is transferred to the separation position calculation device.

On the other hand, in the space detection device 83, if there is no space position, the separation position X'(k+1
) is taken as the separation position x(k+1) and transferred to T and the separation position calculation device 7. The dividing position x(k
+1) is transferred, the separation position calculating device 7 extracts the character image divided by the dividing position X (k) and the dividing position x(k+1) from the character string image memory, and transfers it to the character recognition device 9. Next, the separation position calculation device predicts the next position to be divided using the +1st division position and character pitch P, and performs the above operation until the end of the input character block is detected. It will be done. In addition, the character recognition device 9
This is a known technology that recognizes input character images into predetermined categories. Furthermore, the aforementioned separation position correction device 8 detected the presence of a space by scanning the character string image memory 2 again, but the space was smaller than the position and width of the plurality of character blocks stored in the character block information register 4. It may also be possible to detect the presence of.

As described above, by using the present invention, it is possible to realize a character separation bag f-neck that can easily divide characters into single characters even when there is contact between characters and improve character separation accuracy.

[Brief explanation of drawings]

FIG. 1 is an example diagram for explaining the present invention in detail. FIG. 2 is a logical block diagram showing a specific embodiment of the present invention. In the figure, 1 is a scanning device, 2 is a character string image memory, 3 is a character block extraction device, 4 is a character block information register, 5 is a character pitch detection device, 6 is a contact character block detection device, and 7 is a separation position calculation device. , 8 is a separation position correction device, 81 is a projection distribution extraction device, 82 is a projection information register, 83 is a space detection device, and 9 is a character recognition device. Susumu Shirahara, one patent attorney. , l゛71 Figure 5 Via 1'2 diagram

Claims (1)

[Claims] Scan multiple character string images written on paper,
- In a character separation device that separates character units, means for sequentially extracting, for each character string unit, the position, width, and height of character chunks that can be separated by spaces from the plurality of character string images; means for detecting a character pitch using the position, width, and height of the character mass; means for detecting a character mass including a plurality of characters; Using the separation position and the character pinch, predict the separation position to be divided next, and use the separation position as a reference,
A separable section with a constant allowable width on the left and right sides is provided, and the separation position is determined by searching from the separation position within the separable section on the upper or lower adjacent character string image, and determining the separation position according to the position where the trowel is first detected. A character separation device characterized in that it has means for correcting.