JP3585386B2 - Processing method of handwritten data in ink data format - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a data processing method for handling handwritten data in an ink data format.
[0002]
[Prior art]
Conventional data formats of handwritten data include an ink data format and a bitmap drawing format. The ink data format holds point data received from the device as point sequence data, and handles data connecting the point sequence as lines, making it easy to move and deform handwritten data on the screen. It has the advantage that the amount of data to be held is only the number of point sequence data. The bitmap drawing format directly writes data in the image data format, and has an advantage that it is easy to handle because data is held as screen data.
[0003]
[Problems to be solved by the invention]
When performing a writing operation by handwriting, in the ink data format, it is easy to operate and process only the written data, but since the data can be handled only as a lump, operations such as erasing a part of a line cannot be performed. Conversely, in the bitmap format, part of the data can be erased, but even part of the data becomes screen data, which results in large-capacity data unsuitable for processing. In addition, since handwritten data depends on the timing of signal input from a hardware handwriting device, signal drops become severe depending on the system load, and smooth drawing cannot be performed.
[0004]
FIG. 5 is a diagram for explaining one of the problems of the conventional ink data format handwritten data. Normally, when a line is drawn by hand using an input device such as a pen, the line 50 is composed of a point sequence 51 including many points, as shown in FIG. Each point 51 is a coordinate point taken in at the input timing of the input device. However, when the input person writes at a high speed or when the system is busy, the number of points taken by the input device is extremely reduced as shown in FIG. 5B, and these sparse point sequences 51a, 51b , 51c, 51d to form a line 53.
[0005]
Now, it is assumed that the handwriting input person has performed an erasing operation of the range 54 on the line 53 formed by connecting such sparse dot sequences 51a to 51e using the eraser as shown in FIG. 5C. . In the case of this example, the point 51c in the erasure range 54 is erased, and at the same time, the line segment connecting the point 51c and the points 51c and 51d adjacent to the point 51c is erased. As shown in (2), the line is erased in a range 55 wider than the handwriting input person intends. Alternatively, when no point is included in the erasing range 54 shown in FIG. 5C, even if the erasing operation is performed using the eraser, no change occurs on the display screen, and the handwriting input is performed. The intentional erasure is not performed.
[0006]
The present invention has been made in view of such a problem of the related art, and has the same operational feeling as the bitmap drawing format while having the simplicity of processing in the ink data format, and has an influence on device performance. An object of the present invention is to provide a data processing method capable of drawing smooth handwritten data while keeping it to a minimum.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention uses an input method by a handwriting device to store a point every time an event occurs in a device, and to connect a series of points into a single line in an ink data format. By automatically supplementing the points between the points having a large distance and making the distance between the points equal to or less than a threshold value, smooth handwritten data independent of an event interval generated in the device is created. Also, as a method of erasing a handwritten figure, short lines before and after the point sequence are erased on the display by setting the point sequence included in the deletion target range to the non-display attribute instead of actually deleting the point sequence data. Take a way to make it look like it was done. In the present invention, since the above-described point sequence interpolation processing is performed at the time of drawing, the front and rear widths of the point sequence become constant, and it is possible to display as if line segments in a specified range were deleted at the time of deletion.
[0008]
That is, the method of processing handwritten data in the ink data format according to the present invention is such that the distance between two adjacent points is equal to or less than the threshold value in the processing method of the handwritten data in the ink data format that forms a line by connecting a sequence of points. It is characterized in that a point is supplemented between two points that are far apart. Specifically, every time one point is input from the input device, the distance between the input point and the previously input point is determined, and when the distance exceeds a threshold, processing for supplementing the point is performed. What should I do?
[0009]
According to this processing method, the points are automatically supplemented between the open points, and the distance between the points is set to be equal to or less than the threshold value. Handwritten data can be created, and even when a part of the data is to be deleted, it is possible to delete a minimum range, that is, delete a line segment that matches the intention of the handwritten input user.
[0010]
The method of processing handwritten data in the ink data format according to the present invention is also directed to a method of processing handwritten data in the ink data format in which a line of points is connected to form a figure formed by connecting lines of the point sequence. When the distance between the accompanying point sequences changes, the points are supplemented so that the distance between two adjacent points is equal to or less than a threshold value.
[0011]
According to this processing method, when the distance of the point sequence changes due to the deformation of the figure, for example, the enlargement processing of the figure, the points are automatically supplemented to make the distance between the points equal to or less than the threshold value, so that handwriting can be performed. The data can be reconstructed into handwritten data with dense points, and when erasing a part of the data, erasure within a minimum range, that is, elimination of line segments matching the intention of the handwriting input person, is possible.
[0012]
In addition, the method of processing handwritten data in the ink data format according to the present invention, when receiving an operation instruction to delete a part of the point sequence, without deleting the data of the point sequence included in the deletion target range, the non-display attribute In order to prevent the display. With this processing, it is possible to delete line segments that match the intention of the handwriting input person, such as in the bitmap format, in the ink data format.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram illustrating an example of a configuration of a handwriting input system that implements the processing method of the present invention. The handwriting input system includes a handwriting data input device 10, a central processing unit 11 for processing and displaying input information as handwritten data, and a handwriting data display device 12. After the data input by handwriting is processed by the central processing unit 11, the handwritten data display device 12 typified by a liquid crystal projector displays a handwritten trajectory as if, for example, writing was actually performed on an electronic board. If the pen trace is changed to an eraser, the trace becomes an eraser, and the handwritten data in the area traced by the eraser is hidden and erased from the display screen.
[0014]
The handwritten data input device 10 can output handwritten data input with a pen or the like as coordinate data, like a tablet or an electronic board. The central processing unit 11 includes a point sequence data acquisition unit 13 that converts the coordinate data of the input handwritten data as point sequence data, a point sequence data synthesis unit 14 that combines the point sequence data as line segment data, and a point sequence depending on the state. It has a point sequence data display section 15 for displaying data as line segments. The point sequence data acquiring unit 13 adds the pen or eraser attribute as the point sequence data using the coordinate data input from the handwritten data input device 10.
[0015]
The point sequence data synthesis unit 14 includes a point sequence data interpolation unit 14a and an erasure range determination unit 14b. The point sequence data interpolation unit 14a compares the interval between the first point and the next point with a threshold value obtained from the logical coordinates, and if the interval is larger, adds points between them. When the point sequence data has the eraser attribute, the erasure range determination unit 14b determines whether there is another point sequence around the point sequence, and if so, changes the attribute of the point sequence to non-display. The point sequence data display unit 15 displays a straight line connecting the preceding and following point sequences according to the attribute of the point sequence, and does not display a straight line with the preceding and succeeding point sequences for the non-display attribute point sequence. As a result, the result of addition and deletion of the line segment is output to the handwritten data display device 12 and displayed.
[0016]
FIG. 2 is a schematic diagram illustrating an example of a method for processing handwritten data in the ink data format according to the present invention. When the input person writes at a high speed or when the system is busy, as shown in FIG. 2A, the number of the point sequences 21a to 21e obtained by the point sequence data obtaining unit 13 is extremely reduced. On the other hand, in the present invention, the point sequence data interpolating unit 14a of the point sequence data synthesizing unit 14 interpolates the point sequence to obtain a point between the coarse points 21a and 21b, a point between the coarse points 21b and 21c, and the like. A fine point 22 is added, and an interval between two adjacent points is set to be equal to or less than a preset threshold. The added fine points 22 are handled in the same manner as the point sequences 21 a to 21 e acquired by the point sequence data acquisition unit 13. The point sequence data display unit 15 connects these point sequences 21a to 21e and the interpolated point sequence 22 to form a line 20, and outputs the line 20 to the handwritten data display device 12. Thus, the display of the line 20 is performed.
[0017]
Now, it is assumed that the handwritten input user has performed an erasing operation on the line 20 using the eraser, as shown in FIG. Then, the erasure range determination unit 14b of the point sequence synthesis unit 14 changes the attributes of the point sequences 21c and 22 included in the erasure range 23 to non-display. The point sequence data display unit 15 creates display data that does not display a straight line between the point sequences having the non-display attribute and a straight line between the preceding and succeeding point sequences and sends the display data to the handwritten data display unit 12. As shown in FIG. 2 (c), a line 24 is displayed in which a part of the line 24 is deleted. In this case, the line 20 is formed by a densely arranged point sequence, and since the interval between the point sequences is equal to or less than the threshold value, the line is erased in a range 25 substantially the same as the erase range 23 intended by the handwriting input person.
[0018]
FIG. 3 is a flowchart of the process in the point sequence data synthesizing unit 14. This processing is executed at intervals of about 30 ms in the case of mouse input, for example, depending on the state of the system. First, in step 31, it is determined whether the writing attribute of the coordinate data acquired by the point sequence data acquiring unit 13 is a pen or an eraser. If the writing attribute is the pen, the process proceeds to step 32, and it is determined whether the point is the first point. If it is the first point, the process proceeds to step 35, where that point is stored, and the process ends.
[0019]
In step 32, if the acquired point is not the first point, the process proceeds to step 33, and it is determined whether or not the distance between the point and the previous point on the same line is larger than a preset threshold. . If the interval is smaller than the threshold, the process proceeds to step 35, where the new point is stored, and the process ends. If it is determined in step 33 that the interval between the two points is wider than the threshold value, the process proceeds to step 34, in which the points are filled with the threshold interval and interpolated. Next, the process proceeds to step 35, where the latest point and the interpolated point are stored, and the process ends. Here, since the size of the threshold is determined by the logical resolution, it depends on the resolution of the handwritten data input device 10 and the handwritten data output device 12.
[0020]
If it is determined in step 31 that the write attribute is the eraser, the process proceeds to step 36 to search for a point sequence of an existing line that falls within the area set in the eraser attribute. Then, the process proceeds to a step 37, at which a non-display attribute is set for the point sequence obtained by the search, and the process is terminated.
FIG. 4 is a schematic diagram illustrating another example of the method for processing handwritten data in the ink data format according to the present invention. Interpolation of a point sequence is necessary not only when drawing a figure, but also when deforming an existing figure. Here, interpolation of a sequence of points when a figure is deformed will be described.
[0021]
FIG. 4A is a schematic diagram showing a graphic 40 of ink data that has been handwritten and stored by the method of the present invention. The figure 40 is composed of a series of points composed of a plurality of points 41, and the interval between the series of points is set to be equal to or smaller than the threshold value by the processing described with reference to FIGS. Now, it is assumed that a deformation process, for example, an enlargement process has been performed on the figure 40. Then, as schematically shown in FIG. 4B, the intervals of the point sequences 41a, 41b, 41c, 41d, 41e,... There is. When an erase operation using the eraser is performed on the enlarged figure, a line similar to the erase range intended by the handwriting input person is erased, causing a problem similar to that described with reference to FIG. . Therefore, in the present invention, when performing a deformation process of a graphic that may increase the interval between the point sequences, the interval between the point sequences is reviewed after the deformation process, and the interval between two adjacent points on the same straight line is checked. If there is a portion where the interval is wider than a preset threshold value, a process of interpolating points at the threshold interval is performed during the interval. FIG. 4C shows the enlarged graphic 43 and the point sequence after the point sequence interpolation processing has been performed. A black circle 44 in the figure is a point sequence inserted by the interpolation processing.
[0022]
FIG. 4D shows a state where an operation of erasing the range 45 using the eraser is performed on the graphic 43 subjected to the enlargement processing. The data of the dot sequence included in the erasure range 45 has the non-display attribute and does not appear on the display screen. At this time, since the point sequence is interpolated and the intervals between the points are dense, as shown in FIG. 4E, erasing is performed in a range 46 substantially the same as intended by the handwritten input user. On the other hand, when the interpolation of the point sequence is not performed at the time of the enlargement processing of the figure as in the present invention, the interval between the point series is coarsened by the enlargement of the figure. As described above, the graphic in the range 47 wider than the deletion range 45 intended by the handwriting input person is deleted.
[0023]
【The invention's effect】
According to the present invention, it is possible to create smooth handwritten data that does not depend on an event interval generated in a device, and it is possible to erase data as intended by an input person. Et al is, by the deformation of the graphic ink data format, even if the distance between the point sequence data for configuration changes, it is possible to figure erased at minimum range.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an example of a configuration of a handwriting input system that implements a processing method of the present invention.
FIG. 2 is a schematic diagram illustrating an example of a method for processing ink-format handwritten data according to the present invention.
FIG. 3 is a flowchart of a process in a point sequence data synthesizing unit 14;
FIG. 4 is a schematic diagram illustrating another example of a method of processing handwritten data in the ink data format according to the present invention.
FIG. 5 is a view for explaining one of the problems of the conventional ink data format handwritten data.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Handwritten data input device, 11 ... Central processing unit, 12 ... Handwritten data display device, 13 ... Point sequence data acquisition part, 14 ... Point sequence data synthesis part, 14a ... Point sequence data interpolation part, 14b ... Erasure range determination part , 15: Point sequence data display section, 20: Line, 21a to 21e: Coarse point sequence, 22: Interpolated point, 23: Erasure range, 24: Partially erased line, 25: Erasure range, 40: graphic in ink data format, 41, 41a to 41e: point sequence, 42: enlarged graphic, 43: enlarged graphic subjected to point sequence interpolation processing, 44: point sequence inserted by interpolation processing, 45: intended deletion Range, 46, 47: erased range, 50: line, 51: point sequence, 51a to 51e: point sequence, 53: line formed by connecting sparse point sequence, 54: erase range, 55: erased Range

Claims (1)

In a method of processing handwritten data in an ink data format in which a line is formed by connecting a series of points , the distance between two adjacent points in the series of points is increased with the deformation of a figure formed by connecting the series of points. Ink data which, when changed , supplements points between two points whose distance has been enlarged and changed so that the distance between two adjacent points in the sequence of points forming the line of the deformed figure is equal to or less than a threshold value. How to process formal handwritten data.

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