JPH0348919A - Handwritten character recognizing device - Google Patents

Abstract

PURPOSE:To shorten the time period where the measurement of coordinates is impossible and to continuously measure the input character coordinates at a high speed by securing an area equivalent to plural characters for a buffer which stores the coordinate data in handwritten characters. CONSTITUTION:The coordinate data in the handwritten input characters measured by a tablet 21 and an input pen 20 are stored in a buffer 23 via a table control circuit 22. A recognizing circuit 24 recognizes the characters. The area of the buffer 23 includes plural areas and the measured coordinate data on the continuous input characters are stored in the vacant areas of the buffer 23. As a result, the time period when the measurement of coordinates is impossible is shortened and the continuous input character coordinates can be measured at a high speed with a handwritten character recognizing device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a handwritten character recognition device that recognizes two-dimensional patterns such as handwritten characters and figures and inputs them into a data processing device or the like.

(Prior art) As an input means for a data processing device in place of a keyboard,
Enter handwritten characters and shapes using a tablet, etc.
There is an online handwritten character recognition technology that recognizes characters and figures from input two-dimensional coordinates and stroke information.

FIG. 2 shows a schematic circuit configuration of the handwritten character recognition device. In the same figure, 11 is the input pen lO on the top surface.
a tablet unit 12 that outputs coordinate data of handwritten characters by performing a writing operation on the tablet unit 11;
3 is a tablet buffer for temporarily storing the coordinate data sequentially sent from the tablet unit 11; 14 is a tablet buffer for recognizing handwritten characters from the coordinate data read out by the tablet control circuit 12 after being stored in the -H tablet buffer 13; A recognition circuit, 15 is a recognition buffer for storing coordinate data to be recognized by the recognition circuit 14, and 16 is a timer that can be set for an arbitrary time and generates signals such as interrupts to the tablet control circuit 12 according to the time. be.

When the tablet control circuit 12 outputs a measurement start command to the tablet section 11, the tablet section 11 measures the coordinate position of the input pen 10. When the measurement is completed, the tablet unit 11 sends an interrupt command to the tablet control circuit 12, and outputs the coordinate data and status (input bench lO
information such as whether or not the tablet is in contact with the tablet unit 11)
and send out. The tablet control circuit 12 receives an interrupt from the tablet unit 11, takes in the coordinate data and status sent thereafter, and stores the coordinate data in the tablet buffer 13. At this time, the tablet control circuit 12 determines whether one character's worth of input has been completed based on the status, the coordinate value, the time the input pen 1O has been away from the tablet unit 11, and the like. When the input for one character is completed, the tablet control circuit 12 transfers the data stored in the tablet buffer 13 to the recognition buffer 15 via the recognition circuit 14, and when the transfer is completed, the data stored in the tablet buffer 13 is transferred to the recognition buffer 15.
The tablet unit 11 then starts measuring coordinates using the tablet unit 11 again. The recognition circuit I4 performs character recognition based on the data stored in the recognition buffer 15.

FIG. 3 shows the timing of the above operations. In the figure, A is a command sent from the tablet control circuit 12 to the tablet unit 11, and B is a command sent from the tablet unit 11.
n1 constant of the writing position coordinates of the input ben lO in , C is the tablet control circuit 12 of the measurement data on the tablet unit
D is when the tablet control circuit 12 detects the end of inputting coordinate data for one character, and the tablet buffer I
Data transfer that transfers the coordinate data stored in 3 to the recognition buffer 15 via the recognition circuit 14; E is the recognition circuit 1;
4 indicates the recognition state in which character recognition is performed based on the data stored in the recognition buffer 15, and F indicates the idle state, which is free time.

(Problems to be Solved by the Invention) In the conventional handwritten character recognition device described above, when a coordinate measurement end interrupt is input from the tablet unit 11 to the tablet control circuit 12, the tablet control circuit 12 takes in the coordinate data and Store in the buffer for use.

At this time, if the tablet control circuit 12 and the recognition circuit 14 share a buffer, the buffer pointer will be manipulated by both, resulting in incorrect processing.

For this reason, the tablet control circuit 12 and recognition circuit I4 have separate buffers 13 and 15.

However, since the tablet buffer 13 only has an area for one character, when the tablet control circuit 12 finishes importing data for one character, before starting to import the coordinate data of the next character, from the tablet/soto buffer 13 Data must be transferred to the recognition buffer 15 via the tablet control circuit 12 and the recognition circuit 14, and during the transfer, the tablet unit l! It is not possible to perform coordinate measurements using Therefore, the tablet portion 11 for one character is
After the ili determination is completed, the measurement is restarted again, and there is a certain amount of time lag as shown by F in Figure 3 (1) before the n1 determination of the next character is performed, and the first part of the next character is There was a possibility that it would not be possible to measure the

The present invention has been made in view of the above-mentioned circumstances, and aims to reduce as much as possible the time during which the n1 constant of coordinates becomes impossible.
It is an object of the present invention to provide a handwritten character recognition device that can perform coordinate measurements continuously at high speed.

[Structure of the Invention] (Means and Effects for Solving the Problems) The present invention has a buffer area for storing coordinate data of handwritten characters output from a tablet unit for a plurality of characters, and While the coordinate data for one character is read from this buffer and sent directly to the recognition circuit to recognize the character, the usage state can be identified.While the coordinate data for one character is read out from this buffer and sent directly to the recognition circuit for character recognition, the next coordinate data output from the tablet unit is stored in an unused area of this buffer. This is a device that stores the coordinate data of handwritten characters. After storing the coordinate data for one character in the buffer, it is necessary to change the buffer storage area in order to store the coordinate data of the next character. Since the coordinate n1 constant becomes impossible only at the time of
The time during which coordinate measurement becomes impossible can be shortened sufficiently so that it does not pose a practical problem, it becomes possible to perform coordinate measurement continuously at high speed, and the recognition rate of characters can be improved.

(Example) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the circuit configuration, where 21 is a tablet section that outputs coordinate data of handwritten characters by writing with the input pen 20 on its upper surface, and 22 is a tablet section that takes in the status and data of the tablet section 21. 23 is a buffer having an area for a plurality of characters for storing coordinate data sequentially sent from the tablet unit 21 and a flag register indicating the use status of each area; 24 is a buffer for storing coordinate data in the buffer 23; The recognition circuit 25 that recognizes handwritten characters from the coordinate data can be set at any time, and the tablet control circuit 22
This is a timer that generates signals such as interrupts.

When the tablet control circuit 22 outputs a measurement start command to the tablet section 21, the tablet section 21 measures the coordinate position of the input pen 20. When the 71N determination is completed, the tablet unit 21 sends an interrupt command to the tablet control circuit 22, and transmits coordinate data and status. The tablet control circuit 22 receives the interrupt from the tablet section 21 and takes in the coordinate data and status (information such as whether the input pen 20 is in contact with the tablet section 21) sent thereafter. Next, the tablet control circuit 22 controls a buffer 23 having an area for a plurality of characters.
It searches for an area in which the flag of the flag register has been reset to indicate that it is unused, stores the coordinate data fetched from the tablet unit 21 in that area, and records the usage status in the corresponding flag register. Set a flag to indicate. At this time, the tablet control circuit 22 determines whether the input of one character has been completed based on the status, the coordinate value, the time the input pen 20 has been away from the tablet unit 21, and the like. If not completed, the buffer 2 is sent from the measurement command to the tablet unit 21 described above.
Repeat steps up to step 3 of storing the coordinate data in the same area. When the input for one character is completed, the tablet control circuit 22 notifies the recognition circuit 24 that the data measurement for one character has been completed, and activates the recognition circuit 24. Thereafter, the tablet control circuit 22 causes the tablet unit 21 to again start determining Jl of the data of the next character. In this case, the coordinate data of the next character is stored in another unused area of the buffer 23 whose flag has been reset.

On the other hand, in the recognition circuit 24, the tablet control circuit 22 of the buffer 23 accesses the area in which data for one character is stored, performs handwritten character recognition, and when the recognition is completed, resets the flag of the area and makes it unused. shall be.

In this way, the buffer 23 has an area capable of storing coordinate data for a plurality of characters, and by switching these areas so that they can be accessed from both the tablet control circuit 22 and the recognition circuit 24, the data transfer time can be reduced. can be eliminated. Therefore, the time during which coordinates cannot be measured from the end of one character input to the start of the next character input is only a short time required for switching the area of the buffer 23, and there is no problem at all in practice.

In the above configuration example, the tablet control circuit 22 is configured as a means for controlling the tablet unit 21, and the recognition circuit 24 is configured as a recognition means for recognizing handwritten characters from the coordinate data stored in the buffer 23. This can also be achieved using software techniques.

C. Effects of the Invention As detailed above, according to the present invention, the area of the buffer for storing the coordinate data of handwritten characters output from the tablet section is made up for a plurality of characters, and the usage status of each area is identified. If possible, while the coordinate data for one character is read from this buffer and sent to the direct recognition circuit 1 for character recognition, the next handwritten character output from the tablet section is stored in an unused area of this buffer. Since the coordinate data is stored in the buffer, after storing the coordinate data for one character in the buffer, the coordinate measurement is performed only for a short period of time when the buffer storage area is changed and set to store the coordinate data of the next character. Therefore, the time during which it becomes impossible to determine the coordinate n1 can be shortened sufficiently so that it does not pose a practical problem, and it becomes possible to carry out continuous coordinate measurements at high speed.
It is possible to provide a handwritten character recognition device that can improve the recognition rate of characters.

FIG. 1 is a block diagram showing the circuit configuration of one command of the present invention;
FIG. 2 is a block diagram showing the circuit configuration of a conventional handwritten character recognition device, and FIG. 3 is a timing chart showing the operating state of FIG.

DESCRIPTION OF SYMBOLS 10, 20... Input pen, 11.21... Tablet part, 12.22... Tablet control circuit, 13.
...Tablet buffer, 14.24...Recognition circuit,
15... Recognition buffer, 18, 25... Timer,
23...Buffer.

Claims (1)

[Scope of Claims] Coordinate input means for inputting position coordinates, coordinate detection means for detecting the coordinate position indicated by the coordinate input means, and coordinate data of handwritten characters obtained by the coordinate detection means. A storage means that has an area for storing a plurality of characters and is capable of identifying the usage status of each area, a recognition means that recognizes a handwritten character from coordinate data for one character stored in the storage means, and each of these 1. A handwritten character recognition device comprising: control means for driving and controlling the means.