JPS6030993B2 - Real-time handwritten character recognition device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention detects unrecognizable characters by comparing real-time character codes including the stroke order, number of strokes, and shapes of handwritten characters with standard character codes registered in a recognition dictionary. The present invention relates to a real-time handwritten character recognition device that determines whether or not a pattern can be stored in a temporary registration buffer and registered as a separate pattern.

BACKGROUND ART Conventionally, real-time handwritten character recognition devices have been used that recognize handwritten Chinese characters by comparing real-time character codes, including stroke order, number of strokes, and shapes, with a recognition dictionary.

In this case, there are large individual differences in character patterns entered during the input process, and it is difficult to cover all variable patterns, such as curly characters, with only a recognition dictionary prepared in advance. If a pattern that deviates greatly from the recognition dictionary is written, the recognition ability can be improved by registering that character in the recognition dictionary. However, without carefully examining the input character pattern, for example, whether it is written using a stable stroke order, number of strokes, shape, etc.
It would be wasteful and the possibility of misreading would increase if keys were issued one after another without determining whether the key was written in such a way by chance. An object of the present invention is to provide a real-time handwritten character recognition device in which character patterns written in a stable writing style are registered in a dictionary as patterns different from standard character patterns.

In order to achieve the above object, the real-time handwritten character recognition device of the present invention includes an input control unit that inputs handwritten characters and specifies whether to recognize or register the input data, and a control unit that inputs handwritten characters and specifies whether to recognize or register the input data, and controls the stroke order, number of strokes, and shape of handwritten characters at the time of recognition. A real-time system comprising a feature extraction circuit that extracts features of a character pattern including a character pattern, a recognition dictionary that stores features of character patterns registered in advance, and a circuit that matches input character patterns with features of character patterns in the dictionary. A temporary registration buffer that is temporarily registered in the handwritten character recognition device when the input character pattern cannot be recognized by the recognition dictionary, and the distance between the subsequent input character pattern and the character pattern in the temporary registration buffer and the number of registrations. and means for registering the corresponding character pattern in the temporary registration buffer in the recognition dictionary based on the result of the discussion determination.

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

To briefly describe the principle of the present invention, the most effective countermeasure is to provide a registration function and recognize the unique characters of each individual, but if the registered characters are not stable, the dictionary Not only does it not contribute to recognition, but it may even lead to misreading.

'Therefore, in order to judge this stability, a temporary registration buffer is provided separately from the recognition dictionary, and a character to be registered, for example, ``Kan'' is first stored there, as shown in FIG. 1a. The characters stored here do not function as a dictionary. Even if the character ``Kan'' is entered in the subsequent input process, it is not recognized yet, so the operator registers it again. At this time, the distance between the first "Kan" and the second "Kan" is calculated, and if it is less than a predetermined darkness value, it is determined that they are the same pattern, the number of registrations is increased by 11, and the predetermined darkness value is set. If this is the case, it is considered a different pattern and the character is newly stored. Fig. 1b shows the case where the number of registrations is 2 for the same pattern, and Fig. 1c shows the case of a different pattern. Repeat the above operations,
When the value of the counter reaches a certain level, the character pattern is determined to be stable and is registered in the recognition dictionary as shown in d of the figure. FIG. 2 is an explanatory diagram showing the configuration of an embodiment of the present invention. In the figure, characters written by a scribe on a tablet 1 for handwritten characters, such as a digitizer, are input to an input control circuit 2, and the input control circuit 2 specifies whether to recognize or register the input data. In this case, input the character pattern into the feature extraction circuit 3 and extract the features.
Based on the address information, the features of the corresponding character patterns are read out from the recognition dictionary 6, the distance between the patterns is calculated by the matching circuit 4, and the degree of similarity is determined by the determination circuit 5 to perform character recognition.

4 If the result of the determination is that the character is unrecognizable, the input control circuit 2 is switched to registration, but in the present invention, in order to determine whether or not the character pattern is stable before formal registration, It leads to the temporary registration control section 20.

That is, when the input control circuit 2 inputs the character pattern and character code to be registered from the tablet 1, it sends the registration character code and a registration start signal to the registration control circuit 10. Registration control circuit 1 receives the signal and sends a latch permission signal to latch circuit 7. As a result, the features of the character pattern that have passed through the feature extraction circuit 3 are latched into the latch circuit 7. Furthermore, the registration control circuit 10 activates the write/read control circuit 11 to read data 0 from the temporary registration buffer 12 to the feature comparison circuit 8 . An unrecognizable character pattern is written in advance in this temporary registration buffer 12. The feature comparison circuit 8 compares the features sent from the latch circuit 7 and the temporary registration buffer 12, and calculates the distance between patterns. The registration determination circuit 9 determines whether the input character pattern should be registered as a dictionary based on the distance between patterns from the feature comparison circuit 8 and information on the number of registrations from the temporary registration buffer 12. The registration control circuit 10 compares the characteristics of the input character pattern with respect to all registered patterns in the temporary registration buffer 2 corresponding to the input character code, and determines the distance between the patterns and the registered religion. I'll return it. When the input character is found to be a stable character pattern that should be registered, the write offer control circuit 11 is activated to officially register it in the dictionary 6. If the character pattern is not stable, it is newly registered in the temporary registration buffer 12. This procedure is as described in FIGS. 1b, c, and d. As explained above, according to the present invention, when recognizing a character by comparing the real-time character code of a handwritten character with a standard character code registered in a recognition dictionary, unrecognizable patterns are stored in a temporary registration buffer and separated. Whether or not to register as a pattern is determined based on the distance between patterns and the number of registrations.

As a result, for example, when a modified character pattern that is always stable with respect to a standard character pattern is used, by registering this as a separate pattern, the number of unrecognizable characters can be reduced in many cases, and misreading can also be prevented.

[Brief explanation of drawings]

1A to 1D are explanatory diagrams of the principle of the present invention, and FIG. 2 is an explanatory diagram showing the configuration of an embodiment of the present invention, in which 1 is a tablet, 2 is an input control circuit, and 3 is a feature extraction circuit. , 4 is a matching circuit, 5 is a judgment circuit, 6 is a dictionary, 7 is a latch circuit,
8 is a feature comparison circuit, 9 is a registration determination circuit, 10 is a registration control circuit, I1 is a write logic output control circuit, 12 is a temporary registration buffer, and 20 is a temporary registration control section. Figure 1 Figure 2

Claims (1)

[Claims] 1. An input control unit that inputs handwritten characters and specifies whether the input data is to be recognized or registered; a feature extraction circuit that extracts characteristics of a character pattern including stroke order, number of strokes, and shape of handwritten characters during recognition;
In a real-time handwritten character recognition device comprising a recognition dictionary that stores characteristics of character patterns registered in advance and a circuit that matches input character patterns with characteristics of the character patterns in the dictionary, the input character pattern is recognized in the recognition dictionary. A temporary registration buffer that is temporarily registered when the character pattern cannot be recognized in the temporary registration buffer, a means for determining whether registration is possible based on the distance between the input character pattern and the character pattern in the temporary registration buffer and the number of registrations, and provisional registration based on the determination result. A real-time handwritten character recognition device comprising: means for registering a corresponding character pattern in a buffer into the recognition dictionary.