JPS63106089A - Online hand-written character recognizing and processing circuit - Google Patents

Abstract

PURPOSE:To shorten a processing time by calculating a distance between strokes once, storing a combination in which the distance between the strokes is decided to be a minimum, and saving the calculation of the distance between the strokes on this combination when the same combination is produced again. CONSTITUTION:A combination storing means 12 stores the combination of feature points in which the distance between the strokes is calculated once and the distance between the strokes is decided to be a minimum at every stroke, and a duplication preventing means 11 compares the combination stored in a combination storing means 12 with the combination processed in combination decision means 5, 6, and if they are the same, the processing on the combination is stopped. Accordingly, the once decided combination is not repeatedly processed, so that the processing time can be remarkably shortened.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an online handwritten character recognition processing circuit;
In particular, the present invention relates to an online handwritten character recognition processing circuit that reduces processing time.

〔overview〕

゛The present invention extracts feature points for each stroke of handwriting data input in time series, creates all combinations with feature points of opposing standard patterns, calculates the distance between strokes, and finds the minimum distance between strokes. In an online handwritten character recognition circuit that determines a combination based on which the corresponding standard pattern is determined and outputs a character type code, the distance between strokes is calculated once, and the above combination with the minimum distance between strokes is determined. is stored, and when the same above-mentioned combination occurs again, the calculation of the distance between strokes for this combination is omitted, thereby shortening the processing time.

[Conventional technology]

FIG. 2 is a block diagram showing an example of a conventional online handwritten character recognition processing circuit.

The coordinate input circuit 1 takes in time-series handwriting data from the operator, the feature extraction circuit 2 extracts feature points for each stroke from this data, and the input cover pattern storage circuit 3 stores input cover patterns that are a collection of these feature points. Remember. Standard patterns, which are standard character data, are stored in advance in the standard pattern storage circuit 9. The inter-stroke distance calculation combination circuit 4 extracts the standard pattern and the input pattern, and synthesizes (n ) combinations are generated, the inter-stroke distance calculation circuit 5 calculates the distance between each feature point of this combination as the inter-stroke distance, and the inter-stroke distance minimum value determination circuit 6 calculates the distance between each feature point of this combination as the inter-stroke distance. to determine the single closest input stroke pattern. The above processing is performed for n stroke patterns to determine the inter-category distance. The inter-category distance minimum value determination circuit 7 determines the standard pattern with the minimum distance, and the recognized character type code output circuit 8 outputs the character type code of the determined standard pattern.

In addition, in FIG. 1, 10 is a control circuit.

[Problem that the invention seeks to solve]

In the conventional online handwritten character recognition processing circuit described above, the character with the smallest difference between the input cover pattern and the standard pattern is recognized. Since this is performed for combinations, there is a drawback that distance calculations are repeated even for strokes that have already been calculated and determined to be the minimum value combination, which increases processing time.

SUMMARY OF THE INVENTION An object of the present invention is to provide an online handwritten character recognition circuit that reduces processing time by eliminating the above drawbacks.

Means for Solving Problem C] The present invention extracts a feature point for each stroke of handwriting data that is inputted in time series, and extracts a feature point from each stroke of handwriting data that is inputted in time series, and extracts a feature point from all the feature points of a predetermined standard pattern that are opposed to this feature point. a combination means for generating a combination, a combination determining means for calculating the distance between each feature point of this combination as an inter-stroke distance, and determining the combination with the minimum distance between strokes, and storing the standard pattern. an online handwritten character recognition processing circuit that includes a standard pattern storage means for storing the combination determined by the combination determination means for each stroke; and a combination storage means for storing the combination determined by the combination determination means for each stroke; The present invention is characterized by including a duplication prevention means for comparing the combination with the combination currently being executed and excluding the combination if the same combination occurs again.

[Effect]

In the present invention, the inter-stroke distance is once calculated by the combination storage means, and the combination of feature points determined to have the minimum inter-stroke distance is stored for each stroke, and the duplication prevention means is used to store the combination of feature points determined to have the minimum inter-stroke distance. The combination stored in the means is compared with the combination being processed by the combination determining means, and if they are the same, the processing for that combination is stopped.

Therefore, in the present invention, a combination once determined is not repeatedly processed again, making it possible to significantly shorten processing time.

If the number of feature points is n, the difference ΔN in the number of calculations between the conventional example and the present invention is as follows.For characters with a large number of strokes (C) where n is large, the processing time can be shortened.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block configuration diagram showing one embodiment of the present invention. This embodiment includes a coordinate input circuit l that takes in time-series handwriting data, and a feature extraction circuit that extracts feature points for each stroke from the handwriting data. A circuit 2, an input pattern storage circuit 3 that stores the input pattern, which is a collection of extracted feature points, in the same format as a standard pattern given in advance, and extracts one input pattern and one standard pattern. an inter-stroke distance combination circuit 4 that generates all combinations between the opposing feature points; an inter-stroke distance calculation circuit 5 that calculates the distance between each feature point of this combination as an inter-stroke distance; An inter-stroke distance minimum value determining circuit 6 that selects the one above-mentioned cover turn that is closest to the standard pattern, and determines that the inter-category distance between the selected input cover turn and the standard pattern is greater than the inter-category distance when other standard patterns are used. an inter-category distance minimum value determination circuit 7 that determines that the inter-category distance is shortest and minimum; a recognized character type code output circuit 8 that outputs the character type code of the standard pattern for which the inter-category distance is determined to be the minimum; a standard pattern storage circuit 9 that stores the minimum distance between strokes, a stroke combination storage circuit 12 that stores for each stroke the above-mentioned combination for which the minimum distance between strokes has been determined by the minimum distance between strokes determination circuit 6, and this stroke combination storage circuit 12. an inter-stroke distance calculation combination duplication processing circuit 11 which compares the previously determined combinations stored in the , and the combinations being combined in the inter-stroke distance calculation combination circuit 4, and excludes the processing of that combination when the same combination occurs again; and a control circuit 10.

The feature of the present invention is that, in FIG. 1, an inter-stroke distance calculation combination duplication avoidance circuit 11 and a stroke combination storage circuit 12 are provided.

Next, the operation of this embodiment will be explained. Coordinate input circuit 1
takes in time-series handwriting data from the operator, the feature extraction circuit 2 extracts feature points for each stroke from this data, performs this for n pieces corresponding to the number of input strokes, and the input cover pattern storage circuit 3 extracts the feature points of this feature point. Memorize the input cover pattern that is a collection. Standard patterns, which are standard character data, are stored in advance in the standard pattern storage circuit 9. The inter-stroke distance calculation combination circuit 4 takes out the input cover pattern and the standard pattern, and calculates (n x n) combinations, the inter-stroke distance calculation circuit 5 calculates the inter-stroke distance of this combination, and the inter-stroke distance minimum value determination circuit 6 generates one input of the closest distance for one standard stroke. Determine the stroke and determine this for n standard strokes. The stroke combination storage circuit 12 stores the strokes of the sequentially determined combinations, and performs the inter-stroke distance calculation combination duplication avoidance circuit 1.
1 prevents previously determined strokes from being selected again for distance calculation combinations based on this information, and as a result, determines n input strokes that are originally short distances for each of the n standard strokes. This is reduced to n+ (n+1)+-・-・-+2+1 combination calculations. The inter-category distance minimum value determination circuit 7 determines the shortest distance between all strokes of the determined combination compared with a plurality of standard patterns, and the recognized character type code output circuit 8 determines the shortest distance between all strokes of the determined combination. Outputs the character type code of the pattern.

When the number of input strokes is n, as described above, in the conventional method, distance calculations are performed (n x n) times to find the shortest distance, but in the present invention, preset combination information is fed back. By doing so, the shortest distance can be found by calculating the distance L-+2. In the case of recognition processing, most of the recognition time is distance calculation time, and other processing time can be ignored, so the distance calculation time in the recognition time can be reduced. (characters with many strokes) are reduced.

〔Effect of the invention〕

As described above, the present invention has the effect of minimizing the time required for distance calculation by reducing the number of combinations when determining the shortest distance between the input cover pattern and the standard pattern. This is particularly effective for characters that occur with many input coordinate values (characters that have a large number of strokes).

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention. FIG. 2 is a block diagram showing a conventional example. 1... Coordinate input circuit, 2... Feature extraction circuit, 3...
- Input cover turn memory circuit, 4... Inter-stroke distance calculation combination circuit, 5... Inter-stroke distance calculation circuit, 6
... Inter-stroke distance minimum value determining circuit, 7... Inter-category distance minimum value determining circuit, 8... Recognized character type code output circuit, 9... Standard pattern storage circuit, 10...
- Control circuit, 11... Stroke distance calculation combination duplication avoidance circuit, 12... Stroke combination storage circuit.

Claims (1)

[Claims] (1) Combination means (1) that extracts a feature point for each stroke of handwriting data input in time series and generates a combination of this feature point and all of the opposing feature points of a predetermined standard pattern. , (2), (3), and (4), and a combination determining means (5) that calculates the distance between each feature point of this combination as an inter-stroke distance, and determines the combination with the minimum inter-stroke distance. , (6), and standard pattern storage means (9) for storing the standard pattern.
), a combination storage means (12) for storing the combinations determined by the combination determination means for each stroke; and a combination storage means (12) for storing the combinations determined by the combination determination means for each stroke; An online handwritten character recognition circuit characterized in that it includes a duplication prevention means (11) for comparing the combinations currently being executed and excluding the combinations if the same combinations occur again.