JPS5941089A - Normalizing device of character pattern - Google Patents

Abstract

PURPOSE:To read out a character pattern on an object with high recognition accuracy even if the character pattern is inclined or shifted at its position by detecting the positional coordinates or two marks and operating these coordinates to nomalize the character pattern. CONSTITUTION:The plane on which the characters 7d on the objects 4d, 4e on a belt conveyer 1, are drawn is parallel with the X-Y plane, the line direction of the character array 7d is parallel with the Z-X plane, but the plane on which characters 7e are drawn has an error angle psi from the X-Y plane and the line direction of the character array 7e has an error angle theta from the X-Z plane. Assuming rectangles having prescribed relation to the characters 7d, 7e, the coordinates X, Y of other three points are calculated by specifying the left lower position of each rectangle as an origin. The X sintheta, Xcostheta cospsi are calculated to determine the coordinates of each point and normalize the character pattern. Consequently, the output of a photoelectric converter 5 is normalized by a processor 6 and is stored in an internal storage device to recognize the pattern.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a pattern recognition device that automatically reads letters attached to the body. In particular, when the object moves on a conveyor belt, The present invention relates to a character pattern reading device for reading simple alphabets, numbers, etc.

For such purposes, conventionally, numerical values have often been displayed using bar codes instead of characters, such as object numbers, as a substitute for numbers. This is because barcode reading 62 does not require pattern matching operations unlike character reading.

Figure 1 is a plan view that does not show an example of a conventional device. (1) is a belt conveyor, (11) and (12) are belt conveyors (
1) both it+ 1. (2) is the moving direction of the belt conveyor (1), and (3) is the guide bar.
) and has a side surface (31) parallel to the moving direction (2) of the belt conveyor (1). (4a).

(4b), (4c each represents an object, (5th is a photoelectric conversion device such as a television camera.) Place the belt conveyor (11) so that the edge (11) of the belt is higher than the green (12). Since the plane of is inclined, (
The article in the state 4a) changes from the state (4b) to the state (4C) when the belt conveyor (1) moves 62 times. ) side surface (31) A photoelectric conversion device (5) placed in the photoelectric conversion device (5) converts the electric signal C into two.

If the heavy phase of the object is light, it will not slide off even if the surface of the belt conveyor (1) is tilted. Table 71 = Using l■ angular coordinates with 1'1q11 as the two axes, make the surface on which characters or barcodes are drawn parallel to the CX-Y plane, which is a right angle C2). to perform photoelectric conversion.

In other words, with conventional equipment, the character nu is calculated using a four-dimensional method (
- Therefore, such devices require mechanical parts such as guide bars and eccentric rollers. The drawback was that it required a large amount of space.

In addition, as shown in Figure 2, even if the horizontal 1 m on which the character (7a) is drawn is in the X-Y plane (2,000 lines), the direction of the rows of the character arrangement is in the Z-X plane (not biparallel). If the object has a complicated shape as shown in Figure 3j-3, the object rotates while moving and the character pattern (7) cannot be corrected.
There is a drawback that the drawn surface of b) cannot necessarily be aligned with the guide bar (3).

Therefore, barcodes were often used in conventional rod devices so that they could be read even if there was some inclination or positional shift, but barcodes cannot be read by ordinary people who do not know the structure of barcodes. Therefore, it is necessary to print the corresponding characters as well, and there is also a drawback that a barcode printer is required to print the barcode. However, the JIS standard had the disadvantage that only barcodes for numbers were established, and there were no barcodes for alphabets or kana characters.

This invention was made in order to eliminate the drawbacks of the conventional ones as mentioned above.
A character pattern that detects the error angle with the plane, the error angle between Z-X 1,000m, and the direction of the rows of the character array, and calibrates the position coordinates of each dot in the dot pattern that makes up the character by converting these error angles. The purpose is to provide a normalization device.

The present invention will be described in detail below with reference to the drawings.

Figure 4 is a perspective view showing one implementation of this invention <y++, and the same reference numerals as in Figure 1 indicate corresponding parts; (4d)
.

(4e) each represents 11 objects, (6) is a storage device,
Processing device including arithmetic processing device etc., (7d), (7e
) are characters on objects (4d) and (4e), respectively, which are the objects of pattern recognition.

As in the case of Figure 1, consider rectangular coordinates of the X, Y, and Z axes, with the optical axis of the photoelectric conversion device (5) as the two axes. Character (7d)
The plane on which is drawn is parallel to the X-Y plane, and the character (7d) is arranged (the direction of the two rows is parallel to the Z-X plane, but the character (7e) is drawn on The plane is X-
Error angle with respect to Y plane? , and the direction of the row in the arrangement of characters (7e) is the z-X plane (Ha has a difference angle θ between the two. However, it is assumed that the surface of the belt conveyor (1) is parallel to the Z-X plane.

In order to recognize a character pattern, it is sufficient to express the density of each pixel constituting the plane on which the character is drawn as a black and white binary signal, and to store this binary signal, a logic "1" or "0" is used.
'' may be stored in correspondence with each pixel (two 1-bit signals).

When the objects (4d) and (4e) come to distort the light converting device (5), if the photoelectric converting device (5) is, for example, a television camera, the characters (7d) and (7e) will be drawn. Scan the plano-concave area, decompose it into each pixel, and calculate the ↑IS of the pixel.
The information is output as a 1-bit signal of logic "1" or "0" and convoluted into the storage device in the processing device (6). This storage device has a 1-bit data structure at the l address, and this address is used for the horizontal scan, ft1, and vertical scan (
Since the bits are changed synchronously, the logical arrangement of the bits in this marking device is similar to the arrangement of the dot patterns representing the characters.

Figure 5 shows the bit logic arrangement in the storage device that stores the dot pattern of the character (7d), and Figure 6 shows the bit logic arrangement in the storage device that stores the dot pattern of the character (7e). Indicates an array. However, the edges indicating the four sides of the rectangle containing letters (7d) and (7e) in Figures 1 and 4 C are not necessarily drawn, so U, R, P, Q in Figure 5, and the letters (7e) in Figure 16 are not necessarily drawn. (J', R',
The four lines connecting P' and Q' are not stored in the storage device, but are shown for clarity in the explanation. That is, imagine a rectangle that allows a predetermined relationship with characters (7d) and (7e), and use the lower left vertex of that rectangle as the origin of the coordinates and the other three vertices R, P, Q (R').

The coordinate positions of P', Q') on the X and Y axes are shown in Figures 5 and 6, respectively. The address positions in the storage device of points corresponding to the 0 and 0' points are not shown in parentheses, but the address positions of other points are converted into coordinate positions using this address position as the origin of the coordinates.

Sentence ′(' (7(1), since ψ=θ−0, the character pattern is represented accurately as shown in Figure 5, and is suitable for use in pattern recognition 1. However, the character pattern (7e )
In this case, since ψ and θ are not 0, the character pattern is represented by 錌++l L brackets It, as shown in Figure 6, and is unsuitable for pattern recognition operation (:).

In this case, compare Figures 1 and 5 with Figures )4□6, IBo,
The points that should be yoLP(xoIyo)+Q(xo, 0) are R'12. Y2), P'(X
o, Yo), Q'l,,Y,), it is possible to calculate the character pattern shown in FIG. 5 from the character pattern shown in FIG. 81'-6. If we call this process normalization of character patterns, we can use the normalized character patterns for pattern recognition operations.

Obtained from the relationship between Figure 4, Figures 1 and 5, and Figure 3161.

Since A is the biaxial distance from the imaging point of the photoelectric conversion device (5) to the origin of the seat pillow (0 is 0'), ψ・θla is unknown, and (0, yo ) and CX2. The relationship between (Y2), the relationship between (X(1+3'o) and (Xo, Yo), (
xo.

0) and (X,, Y,), ψ, θ, and a can be determined by substituting any two sets of relationships between Equation (41, +2) +:, and A, a, ψ, If θ is known, give the values of (X, Y) from equations (11 and (21) and calculate (x, y)
It is possible to derive a formula to calculate the value of , and use this formula to normalize the character pattern.

However, in general (= is A>> (a + (xcosθ−ysinθ) si
n tp ) ---(3), and therefore the formula (
1> , +2) is X = (xcosθ−y sinθ)
cos ψ−(41Y −X sin θ+y cos θ
---It can be approximated by (5).

Since the unknowns in equations (4) and (5) are ψ and θ,
For example, point P (XOr 'IO) and P' (Xo, Y
o) using the relationship Xo= (xocos O-yosi
nθ) eosψ −−−+6)1Yo= xosi
nθ+yocosθ −m−(7) to 0.
Calculate ψ and get xO′+y. ', calculate the value of sinθ from the value of cO8θ, and use the formula (
4).

Obtaining from (5), character patterns can be normalized using this formula +10) and (II).

In order to simplify the explanation, the points 0 and 0' are assumed to be the origin of Zagiri, and when the condition of equation (3) is met, ψ and θ are calculated from the relationship between the coordinate positions of points P and P', and the characters are Normalize the pattern, and then normalize the Fumiko pattern from any two of the general cases (2) R9R' relationship, p, p' relationship, Q, Q' relationship (7). but,
Adding a more general consideration, when the condition of equation (3) is satisfied, the character pattern of the character can be corrected if the positional image of two vertices on the diagonal line C of the rectangle of known dimensions containing the character can be detected. Generally, it is clear that the character pattern of the character can be normalized if the position coordinates of any three of the four vertices of the rectangle can be detected.

Figure J17, Figures 1 and 8, and Figure 319 each display positional information regarding rectangles of known dimensions using marks. , +9) tt Marks representing the four sides of the rectangle, and any of these marks can create 4l6
It is possible to detect the address position corresponding to 4'll in figure U', )''', and if necessary, the address position corresponding to It is easy to convert from the address position to the seat position.Of course, the four sides of the rectangle indicating the rectangular area may be printed in advance and used as marks.

In addition, equipment cost 1 of this invention: Mechanical l1l-t of conquering
It is also possible to use the character pattern normalization method in combination to simplify the character pattern normalization gate to history ζ2+yIj.

As described above, according to the present invention ≦2, the character pattern on the object can be normalized by detecting the positions of the two marks and performing arithmetic processing, so that the character pattern on the object is free from inclination and positional deviation. It has the advantage of being able to be read with high recognition and accuracy.

[Brief explanation of the drawing]

Figure 111 is a plan view showing the conventional device.
Figures and 3 south are diagrams showing examples of characters attached to objects, respectively;
Figures 117, 2181\41, and 9 (J
FIG. 2 is a diagram showing two rectangles C each having known dimensions and a corresponding position change mark. (1)... Belt compaire, (4d), (4e)
...Object, (5)...Photoelectric conversion device, (6)
...processing device, (7d). (7e)...Character, (8)...Mark indicating the vertex of the rectangle, (9)...Mark indicating the side of the rectangle. Note that the same reference numerals in the figures indicate corresponding parts. Agent Makoto Kuzuno - Fig. 7 Fig. 8 Fig. 9
No. 2, Name of the invention Character pattern normalization device 3, Complement 1: 'IL f'l・t(1) Relationship Permit IKi Person Address: Marunouchi 2J''11, 111-ku, Chiyo, Tokyo
Name 2 and 3 (4, (601) - Ryodenki Co., Ltd. Representative Taiga 111 Jin Hachibe 4, Agent address Marunouchi Tsume J'L1, 111-ku Chiyo, Tokyo
2 total 3';) 5, Subject of amendment (1) Scope of claims of specific illness (2) 41 of detailed description of invention of clear full t! ! 1
6. Contents of the amendment (11. Amend the claims in Book 1 of the Claims as shown in the attached sheet. (3) In the 4th and 5th lines of page 6 of the same page, correct the words "for each dot of the dot pattern" to read "for each point." (4) Off page of the same page Lines 4 to 6 [both black and white... 1-bit signal] are deleted to read ``information.'' 15) Same ■, off page lines 11 to 18 The phrase ``Information on the pixel... has a similar shape.'' is corrected to ``The ↑) Y information of the pixel causes the storage device in the processing device 1 (6) to frown slightly.'' (61 same book off page line 19 to o page 8 line 2 [1.
5 (Koha...indicates the arrangement.) The 5th shi; 1 shows the character pattern of the character (7d), and the 6th figure shows the character (7d).
The character pattern of e) is shown. ” he corrected. (7) Delete the statement ``Although the address position in the storage device is not 0,'' in the 13th and 14th lines of page 8 of the same ■ Katana. 181 Shisho, page 9, line 9, ``Processing'' is changed to ``Processing is''. (9) On page 9 of the same document, lines 9 to 10, correct the phrase ``to be referred to as,'' by saying ``is.'' 7. Attached catalog (1.1 of old amended patent claims) 1 copy (
Attachment 2, Claims (1) The positions of two diagonal vertices as the minimum positional information regarding the rectangular area of known dimensions that includes the characters targeted by the pattern UF11t. A photoelectric conversion device that detects the coordinates and the position coordinates of each point on the character pattern as position coordinates on an X-Y plane of rectangular coordinates with the optical axis as the Z axis, and a memory that stores the output of this photoelectric conversion device. A character pattern normalization device comprising: a device; and means for normalizing a character pattern with the two vertices. (21 photoelectric conversion device is located on the diagonal opening of the rectangular area.
2. The character pattern normalization device according to claim 1, wherein the character pattern normalization device detects the position coordinates of marks drawn at vertices. (3) The photoelectric conversion device detects the position coordinates of the mark drawn at any three of the four vertices of the rectangular area. Character pattern normalization device according to item 1. (The 41 light output conversion device detects the position coordinates of each point of a pattern that constitutes a figure drawn on the four sides of a rectangular area.) Leopard. Procedural amendment (voluntary), Commissioner of the Japan Patent Office, January 1, 1982, 1, Indication of the case, Patent Application No. 151473, 1982, 2,
Name of the invention Character pattern normalization device 3, person making the amendment Representative Hitoshi Katayama Part 4, f (embedding 5, subject of amendment (11) Detailed description of the invention in the specification (2: Drawings of the specification) Brief explanation column 6, content of amendment +11 Specification O page 8, lines 12 to 16, “0
and corresponds to 07 points...as shown. ” will be deleted. (2) In the 12th line of the same book, lines 11 and 13, the words "address position" are corrected to read "coordinates." (3) State O page 12, No. 14? ■Delete the line ``It is easy to change from the address position to the za position'' in lines 5 to 5. (41st book, page 13, lines J to 12 The phrase ``A diagram showing the arrangement of letters, respectively'' should be corrected to ``A 9-character pattern k 7y<su diagram.''

Claims (4)

[Claims] (1) Among the positional information regarding a rectangle of known size that contains the character to be pattern recognized, the minimum positional information is the positional coordinates of the two vertices on the diagonal set and each of the dot patterns that make up the character. a photoelectric conversion device that detects the position coordinates of the dot as a position machine on the X and Y coordinate axes of a rectangular coordinate axis with the optical axis as two axes; a storage device that stores the direction of the output of the photoelectric conversion device; The X of the ml of the rectangle is compared to the distance on the Z axis from the device to the rectangle.
- Means for calculating these error angles from the position coordinates of the two vertices assuming that both the error angle from the X flat curve and the error angle from the 2-X flat curve of one side of the rectangle are small, and the calculated error A character comprising means for normalizing a character pattern and means for storing the normalized character pattern from the corner to the position coordinates of each dot when the error angle is zero. Pattern normalizer. (2) The character pattern normalization device according to claim 1, wherein the photoelectric conversion device detects the position coordinates of marks drawn on diagonals (two vertices) of a rectangle. (3) The character pattern normalization device according to claim 1, wherein the photoelectric conversion device detects the position coordinates of a mark drawn at any three of the four vertices of a rectangle. (4) The character pattern normalization device according to claim 1, wherein the photoelectric conversion device detects the position coordinates of each dot of a dot pattern that forms the bottom of a figure drawn on the four sides of a rectangle. .