JPS60217475A - Loop detecting system and pattern recognizing device utilizing it - Google Patents

Abstract

PURPOSE:To obtain an accurate detection by generating a pattern taking a straight line connecting adjacent sampling points as a diagonal line, writing sequentially the pattern on a storage section and deciding as a loop when other pattern is written to a write coordinate already. CONSTITUTION:Stroke information of an input pattern inputted in a way of handwriting from a coordinate input device 11 is sampled and outputted sequentially as a time series sampling data, stored in a register 12 and a position coordinate data before one sampling is transferred to a register 13. A rectangular pattern generating circuit 14 inputs the coordinate data stored in the registers 12, 13, obtains the coordinate at other corner of a rectangle and the rectangular pattern represented at each coordinate is generated. The rectangular pattern generating circuit 14 writes a generating pattern data to the coordinate corresponding to the sampling point of a two-dimension storage section 15 and when other pattern data is written already, it is decided that the stroke of the input pattern forms a loop.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention provides a loop that can easily and reliably detect whether or not an input pattern represented as a connection of sample points in time series forms a loop. Regarding detection method.

[Technical background of the invention and its problems] In a system that recognizes an input character/symbol pattern and inputs the recognition result into a computer etc. for information processing, it is necessary to recognize the characteristics of the input character/symbol pattern. It is important to extract accurately. One of the features used in this recognition process
There is also information on whether or not the strokes of the input pattern form a loop. In particular, such loop formation information is important for BII& processing of input pattern strokes input via a coordinate input device such as a tablet device.

Conventionally, for example, as shown in FIG.
It is determined whether or not the input cover turns form a loop by determining whether or not the lines b and 2m intersect.

Specifically, the position coordinates of adjacent sample points are (X2.
y2) (x3. y3) and (x8. y8) (
x9. y9), the straight line connecting these sample points is Y-V3= (y2-y3> (X-x3) / (x
2-x3)Y-18= (y9-y8) (X-x8
) / (x9-x8), and it is calculated whether these two straight lines intersect. In this case, the common plate is taken as the coordinates of the intersection point of the straight lines.

However, in order to detect the presence or absence of intersections of the straight lines connecting the sample points and to detect the loop of the input Kabataan in this way, it is necessary to perform the above-mentioned calculations for all the combinations of straight lines. This resulted in a huge amount of calculation.

Moreover, the calculation took a considerable amount of time.

[Purpose of the invention]

The present invention has been made in consideration of the above circumstances, and its purpose is to provide practicality in which it is possible to easily and accurately detect whether or not the stroke of an input pattern forms a loop. It is an object of the present invention to provide a pattern recognition device that can recognize the cover pattern with high accuracy by using a loop detection method with high accuracy and the loop detection results.

[Summary of the invention]

The present invention generates a predetermined pattern whose diagonals are straight lines connecting adjacent sample points of a plurality of time-series sample points indicating an input cover pattern, and stores this predetermined pattern on a two-dimensional plane storage unit at the sample points. The pattern is written in order according to the position coordinates, and when another pattern has already been written at the writing coordinate position, it is determined that the strokes of the previously written cover pattern form a loop. It is. Then, this loop detection result is used as one feature information of the input cover pattern to perform the recognition process of the input cover pattern.

In particular, by using, as the predetermined pattern, a line pattern or a surface pattern in which diagonal lines are straight lines connecting adjacent sample points and rectangles parallel to the coordinate axes of the two-dimensional plane storage unit are used as the basic pattern, the two-dimensional Loop detection can be performed accurately regardless of the matrix-like coordinate arrangement of the plane storage section.

〔Effect of the invention〕

Thus, according to the present invention, the input cover pattern forms a loop only by determining whether another pattern has already been written at the write coordinate position of the pattern written on the two-dimensional planar storage unit. It is possible to easily and accurately detect whether or not the vehicle is present. Moreover, since the predetermined pattern connecting adjacent sample points has a basic pattern of a rectangle parallel to the coordinate axis of the two-dimensional plane storage unit,
The pattern generation is simple, and the amount of calculation processing required for this can be significantly reduced, thereby achieving great practical effects, such as shortening the processing time. In addition, since the input cover pattern is recognized using the feature information regarding the loop of the input cover pattern detected with high precision in this way, it becomes easier to distinguish between characters with strong similarities, and the pattern recognition accuracy can be improved. Effects such as making it possible to improve the performance can be achieved.

(Embodiment of the Invention) Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

2 and 3 are for explaining the concept of the loop detection method according to the present invention, and FIG. 2 shows a plurality of time-series sample points representing an input pattern. These time-series sample points are obtained by equally dividing an input stroke inputted via a coordinate input device such as a tablet device from the start point to the end point, and the sample points are the dividing points, together with the above-mentioned start point and end point. 1a, lb, ~1n, etc. Therefore, this time series sample point 1
The stroke of the above-mentioned cover turn is expressed by line segments connecting a, Ib, to 1n in order.

However, in this method, the time-series sample points Ia, Ib,
Straight lines 2a, 2b connecting ~1n adjacent sample points, ~
A predetermined pattern, for example, rectangular patterns 3a, 3b, ~3m, having a diagonal line of 2m is generated, and these rectangular patterns 3a, 33~3m are placed at coordinate positions corresponding to the sample points on the coordinate plane of the two-dimensional plane storage unit. They are written in order. Then, the rectangular patterns 3a, 3
b. When another pattern has already been written in the coordinate plane position for writing the "-" button, this is detected as a loop in the stroke of the entered cover turn.

The rectangular patterns 3a, 3b, .about.3m whose diagonals are the straight lines 2a, 2b, .about.2m connecting the adjacent sample points are rectangles parallel to the coordinate axes of the coordinate plane of the two-dimensional plane storage section, as shown in FIG. In other words, the coordinate positions of the two adjacent sample points are (x2.y2), (X3°y3)
, the other coordinate positions of the rectangular pattern are (x3. y2) and (x2., y3). This rectangular pattern indicates that there are strokes connecting sample points in the diagonal direction. Therefore, when trying to write a newly generated rectangular pattern on the coordinate plane, if another rectangular pattern has already been written at that coordinate position, the stroke connecting other sample points in that coordinate area means that it already exists. Note that overlapping rectangular patterns also occur when the strokes do not intersect and the straight lines connecting the sample points are nearly parallel and close to each other, but in this case as well, the strokes are considered to form a loop. There is no problem because it can be done.

FIG. 4 shows a configuration example of a loop detection circuit that performs loop detection by applying this method described above, and 11 is a coordinate input device. The stroke information of the input pattern input by hand through the coordinate input device 11 is appropriately sampled and sequentially output as time-series coordinate data of sample points. The register 12 stores the position coordinate data of the sample points sequentially output from the coordinate input device 11, and also transfers the position coordinate data of the previous sample stored in the register 12 to the register 13 at the next stage. There is. The rectangular pattern generation circuit 14 inputs the positional coordinate data stored in these registers 12 and 13, determines the positional coordinates of the other corners of the rectangle as described above, and generates a rectangular pattern indicated by each of the positional coordinates. is occurring. Then, the pattern generation circuit 14 determines whether or not other pattern data has already been written at the writing position of the rectangular pattern data in the two-dimensional planar storage section 15 constituted by a pattern memory or the like. When pattern data does not exist, the generated pattern data is written at the coordinate position corresponding to the sample point on the coordinate plane of the two-dimensional plane storage section 15. Furthermore, if other pattern data has already been written at the pattern data writing position in the two-dimensional plane storage section 15, this is determined to be the stroke of the input cover pattern forming a loop.

As described above, according to the present method, the loop of the input pattern stroke can be detected using a very simply configured circuit, and the detection method is also very simple. Furthermore, as described above, since the rectangular pattern is along the coordinate axes of the two-dimensional coordinate plane, the pattern generation process is simple and requires less calculation. Therefore, it is possible to efficiently detect input stroke loops in a short time.

In addition, instead of the above-mentioned rectangular pattern, for example, the pattern shown in FIG.
As shown in Fig. 5(b), two straight line patterns forming the sides of a rectangular pattern may be used, or a circular pattern may be used as shown in Fig. 5(b) because it is easy to generate a circular pattern. If the two straight lines are used, the pattern can be easily written on the two-dimensional coordinate plane, and the processing time can be further shortened.

By the way, the loop detection described above is used in pattern recognition processing, for example, in the following manner. FIG. 6 is a schematic configuration diagram of a pattern recognition device showing an example thereof, in which the coordinate input device 21
This system recognizes handwritten character patterns input from the computer in real time and inputs them into a computer.

Time-series sample point coordinate position data indicating the strokes of the input character pattern supplied from the coordinate input device 21 is supplied to the stroke detection circuit 22 to detect the input strokes. The input stroke detected by the stroke detection circuit 22 is provided to the loop detection circuit 23 in time series, for example, as a plurality of sample points that approximate it. For example, when the character pattern "su" is input as shown in Figure 7, sample points representing the stroke are given as a coordinate series as shown in Figure 8. The loop detection circuit 23 detects the presence or absence of a loop for such time-series sample points as described above. Then, the feature extraction circuit 24 detects the features of the input cover pattern according to the loop information of the stroke detected by the loop detection circuit 23 and the information of the input stroke detected by the stop edge detection circuit 22. The recognition processing section 16 compares the characteristics with the characteristics of standard patterns of various recognition categories registered in advance in the standard pattern dictionary 25, and the recognition result for the input cover pattern is obtained.

In this way, detecting input stroke loops as a feature in recognizing input character patterns and the like plays an important role in improving recognition 1111Ji. In addition, great practical effects can be obtained, such as making it possible to reliably distinguish between ``ne'' and ``ne''. Therefore, the present device, which detects input stroke loops easily, accurately, and in a short time and uses them as characteristic information of the input pattern for recognition processing, has great effects such as high recognition accuracy. I can do it.

Note that the present invention is not limited to the embodiments described above. For example, the characteristic information of the input pattern used in pattern recognition processing 1 is not limited to the stroke information and loop information described above. Also, the recognition processing method is not particularly limited. In short, the present invention can be implemented with various modifications without departing from the gist thereof.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a conventional loop detection method, FIGS. 2 and 3 are diagrams showing a loop detection method according to an embodiment of the present invention, and FIG. 4 is a loop detection circuit to which the embodiment method is applied. , Figure 5 is a diagram showing other pattern examples used for loop detection, Figure 6 is a schematic diagram of a pattern recognition device that uses input pattern loop information as feature data, and Figure 7 is a diagram showing input pattern patterns and their FIG. 8 is a diagram showing an example of sample points, and FIG. 8 is a diagram showing a coordinate series of sample points. 1a, lb, ~11)
...sample point, 2a, 2b to 2m...straight line, 3a, 3
b~3m... Rectangular pattern, 11... Coordinate input device, 12.13... Register, 14... Rectangular pattern generation circuit, 15... Two-dimensional plane storage unit, 23...
・Loop detection circuit. Applicant's agent Patent attorney Takehiko Suzue No. 1 Figure 4 Po

Claims (6)

[Claims] (1) means for sequentially generating predetermined patterns whose diagonal lines are straight lines connecting adjacent sample points of a plurality of sample points input in time series through a coordinate input device; means for sequentially writing into a two-dimensional plane storage unit corresponding to the positional coordinates of each sample point; and when another pattern has already been written at the write coordinate position of the predetermined pattern in the two-dimensional plane storage unit; A loop detection method, comprising: means for determining that the input cover turns sequentially connecting the sample points form a loop. (2) The predetermined pattern whose diagonal line is a straight line connecting adjacent sample points is a line pattern that connects the adjacent sample points using a rectangle parallel to the coordinate axis of the two-dimensional plane storage unit as a basic pattern, or The loop detection method according to claim 1, wherein the loop detection method is provided as a surface pattern. (3) The line pattern that connects adjacent sample points using a rectangle parallel to the coordinate axis of the two-dimensional plane storage unit as a basic pattern constitutes the lines that form the two adjacent sides of the rectangle. A loop detection method according to claim 2. (4) means for sequentially generating predetermined patterns whose diagonal lines are straight lines connecting adjacent sample points of a plurality of sample points inputted in time series through a coordinate input device; means for sequentially writing into a two-dimensional plane storage unit corresponding to the positional coordinates of each sample point, and when another pattern has already been written at the write coordinate position of the predetermined pattern in the two-dimensional plane storage unit; means for determining that the input cover turns connecting the sample points in sequence form a loop; and means for recognizing and processing the input cover turns by using information regarding the loop of the input cover turns determined by the determination means as one feature information. A pattern recognition device characterized by comprising: (5) The predetermined pattern whose diagonals are straight lines connecting adjacent sample points is a line pattern that connects the adjacent sample points using a rectangle parallel to the coordinate axis of the two-dimensional planar storage unit as a basic pattern, or 5. The pattern recognition device according to claim 4, wherein the pattern recognition device is provided as a surface pattern. (6) The line pattern that connects adjacent sample points using a rectangle parallel to the coordinate axis of the two-dimensional plane storage unit as a basic pattern constitutes the lines that form two adjacent sides of the rectangle. A pattern recognition device according to claim 5.