JPH046996B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of a real-time character recognition device that recognizes characters based on handwriting input in real time.

Conventionally, there is already a method of recognizing characters based on handwriting input in real time. For example, the special request
A method using pattern matching as described in Japanese Patent No. 194174 (hereinafter referred to as Document 1) is effective. When recognizing characters, it is necessary to determine from where in the written handwriting a single character begins. There have been several methods for this determination.

The first method is to provide a character frame on the tablet into which handwriting is input, and to treat the handwriting written within the character frame as the handwriting that constitutes one character. In this method, the end of writing one character is detected by starting writing the next character in the adjacent character frame. For this reason, there was a drawback that the end of writing a character could not be detected until the next character began to be written. In order to know the recognition result of the last character, it was necessary to perform a special operation such as pressing the key switch after writing the character.

The second method is to measure the time it takes for the tip of a writing pen to leave the tablet and land on the tablet again, that is, the time between strokes of a character, and to set this time to a certain threshold. This is a method that marks the end of writing a single character when the number exceeds this point. With this method, once you start writing one character,
You must write all the letters in one go without stopping until the end of the letter. When writing kanji with a large number of strokes, it is common to have to pause the pen while writing. This method had the disadvantage that if the user rested the pen while still writing a single character, it would be mistakenly determined to be the end of the character, making it impossible to input the character correctly.

The purpose of the present invention is to correctly detect the end of writing a character without performing any special operations, and to prevent it from being mistakenly determined as the end of writing even if the pen rests in the middle of writing. The purpose of this invention is to improve the usability of a real-time character recognition device by achieving the above two points.

According to the present invention, there is provided a tablet unit that detects positional information of a pen tip, pen on/off, and proximity information when writing characters, and a state in which the pen tip is outside a character frame provided on the tablet unit. and a character recognition unit that recognizes a character when it is determined that the character is at the end of writing based on the detection result of the detection unit. A real-time character recognition device consisting of the following is obtained.

The present invention will be described in detail below based on a specific example. FIG. 1 is a block diagram of an embodiment of the present invention. The tablet 1 outputs pen tip position information X, Y and pen tip on/off/proximity information P. Information P is 3 of 0, 1, 2
Takes the seed value. If the pen tip is closer than the surface of tablet 1, position information X, Y
is output at fixed time intervals (for example, 100 points per second). When the pen tip is on the tablet surface, the information P is 1, and when it is far away and within the close range, a value of 0 is output at the same timing as the position information X and Y. When the pen tip moves away from the surface of the tablet 1 by more than a certain amount and comes out of the close range, the information P takes a value of 2. This information can be obtained by using a tablet, for example, a DT-3000 tablet manufactured by Daini Seikosha. FIG. 2 is a view of the front surface of the tablet 1. On the tablet 1, as shown in FIG.
It is assumed that a character frame 21 is written. One character is written within this character frame 21.

The format memory 2 stores the coordinate values of the boundaries of the character frame 21. When a character is written and the pen is turned on for the first time and the value of information P becomes 1, the coordinate value AB of the boundary of the character frame including the position X and Y of the pen tip at this point is output from the format memory 2 and the boundary is It is held in register 3. Thereafter, when the information P is 0 or 1, the position information X, Y from the tablet 1 is compared with the content of the boundary register 3 by the comparison circuit 4.

When the pen tip goes outside the current character frame and the information P
When the value of is 0, the comparison circuit 4 outputs a clock start signal S. This time measurement start signal S passes through the OR circuit 5 and causes the time measurement circuit 6 to start time measurement. The clock circuit 6 measures the time since the clock start signal S is input, and when a certain amount of time (for example, 500 msec or more) has elapsed, the character recognition circuit 7
A recognition start signal T is output to the target. When the pen tip returns to the current character frame, the comparison circuit 4 outputs a clock reset signal R, and the time measurement of the clock circuit 6 is reset.

When the pen tip is more than a certain distance from the surface of the tablet 1, the value of the information P becomes 2. In this case as well, the OR circuit 5 outputs the timing start signal S.

When the pen tip goes outside the current character frame and the information P
When the value of is 1, that is, when a character is written in the next character frame, the comparison circuit 4 directly outputs the recognition start signal T.
is output. At this time, the value of boundary register 3 is also updated.

Position information X, Y and information P are held within the character recognition circuit 7. When the recognition start signal T is input, the held position information X, Y and information P
Characters are recognized based on This character recognition circuit 7
For this purpose, we use a method using pattern matching as described in Reference (1).

If you want to rest the pen while writing, keep the pen close to the tablet surface and the clock circuit 6 will be activated.
No time measurement is performed. Therefore, even if you take a break from the pen while writing a character, it will not be mistakenly determined that you have finished writing the character. Character recognition results can be obtained by moving the pen to the next character frame or by moving the pen further away from the tablet. As described above, according to the present invention, there is an advantage that the end of writing of a character can be correctly detected without any special operation. Furthermore, even if the pen is removed from the tablet, if it is within, say, 500 milliseconds, the user can continue writing.

Although one embodiment of the present invention has been described above, the present invention is not limited to this embodiment. For example, all currently known character recognition methods can be used as the character recognition method in the character recognition circuit 7.

The clock circuit 6 is not an essential element in configuring the present invention. If the clock circuit 6 is not provided, a clock start signal S causes the character recognition circuit 7 to start the recognition operation.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention.
FIG. 2 is a diagram showing an example of the surface of the tablet 1. In the figure, 1 is the tablet, 2 is the format memory, 3 is the boundary register, 4 is the comparison circuit, and 5 is the OR
6 is a clock circuit, 7 is a character recognition circuit, and 21 is a character frame.

Claims (1)

[Claims] 1. A tablet section that detects the position information of the pen tip when writing characters, on/off of the pen, and proximity information, the state in which the pen tip is outside the character frame provided on the tablet section, and the proximity range. A real-time character comprising a detection unit that detects two states: a state in which the character is outside, and a character recognition unit that recognizes the character when it is determined from the detection result of the detection unit that the character is at the end of writing. recognition device.