JPH02187877A - Graphic recognizing device - Google Patents

Abstract

PURPOSE:To facilitate a graphic input work by recognizing a graphic as a straight line having the same inclination as that of a plotted segment when the graphic is compared with a reference straight line, and the inclination difference between them is less than a prescribed value. CONSTITUTION:When the graphic is inputted, a coordinate data identification part 2 gives time sequential coordinate data to be given subsequently to a graphic identification part 6. The graphic identification part 6 detects the feature of the graphic and detects the classification of the graphic. When the detected result is the straight line, the start point and the end point of the time sequential coordinate data are given to a straight line identification part 7. The part 7 gives the coordinate data to an inclination detecting part 5 and receives inclination data detected by the detecting part 5. Next, the straight line identification part 7 gives the coordinate data of the start point and the coordinate data of a remote point stored in a memory 3 to the inclination detecting part 5, makes the part 5 obtain the inclination of a straight line to connect both the points, and receives the data. Further, the straight line identification part 7 compares the inclination data of the segment plotted on an input surface with the respective inclinations of a horizontal axis, a vertical axis, the straight line to connect the start point and the remote point, and the reference straight line stored in a memory 4, detects to which inclination the inclination of the segment is the closest, and sets the inclination as the inclination of the plotted segment.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device for recognizing figures drawn using a keyboard, a mouse, etc. in a computer system or word processor.

[Prior art and problems to be solved by the invention] Conventional figure recognition devices recognize circles that are registered in advance.

Compare the shapes of triangles, squares, straight lines, etc. with handwritten shapes drawn using a keyboard, mouse input pen, etc.
Registered figures whose shapes are similar are recognized as drawn figures.

Further, when a drawn figure is recognized as a straight line, if its slope is within a predetermined angle range from the horizontal or vertical direction on the coordinates, it is recognized as a horizontal or vertical line. On the other hand, if the slope is greater than or equal to a predetermined angle range, the drawn line segment is recognized as a straight line with the same slope.

In a figure recognition device configured as described above, when an operator attempts to draw a three-dimensional figure based on perspective or a group of straight lines with a certain slope using the keyboard, mouse, and input pen, the operator's visual ability is unable to accurately draw a three-dimensional figure or a group of straight lines with a certain slope. It is difficult to draw a group of straight lines with a slope of .

Therefore, for example, a guide line is once drawn toward one point in the distance where the line segments converge, and after the target line segment is drawn according to this guide line, the guide line is erased. Alternatively, the length of the line segment in the X direction and Y direction, the coordinate values of the start point, the end point, etc. are calculated according to the slope of the required line segment, and an accurate line segment is drawn while referring to the coordinate display on the input surface.

However, the guide lines must be erased later, making the input work complicated. Further, when the required length and coordinate values are calculated, the figure must be accurately drawn according to the calculated values, which poses a problem that manual work is difficult and complicated.

The present invention has been made to solve these problems, and is a figure recognition method that can recognize roughly drawn hand-drawn figures as correct three-dimensional figures according to perspective or as a group of straight lines having a certain slope. The purpose is to provide equipment.

[Means to solve the problem]

The figure recognition device of the present invention recognizes a figure drawn on its input surface, and includes means for predetermining a straight line having a predetermined slope as a reference straight line, and an inclination of the reference straight line.
A means of comparing the slope of a drawn line segment and the result of the comparison,
If the difference in slope between the reference straight line and the drawn line segment is less than or equal to a predetermined value, the drawn line segment is characterized by comprising means for recognizing the drawn line segment as a straight line having the same slope as the base straight line. .

[Effect]

The figure recognition device of the present invention compares a drawn line segment with a reference straight line having a predetermined slope, and as a result of the comparison, the difference in slope between the reference straight line and the drawn line segment is a predetermined value. If the following is true, the drawn line segment is recognized as a straight line with the same slope as the base $ straight line.

Furthermore, as a result of the comparison, if the difference in the rotation is greater than or equal to a predetermined value, it is recognized as a straight line with the same slope as the drawn line segment.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on drawings showing embodiments thereof.

FIG. 1 is a block diagram showing the configuration of a figure recognition device according to the present invention. 1 in the figure is a handwritten figure input unit that detects the trajectory of the input pen moving on the human surface as time-series coordinate data and outputs it to the coordinate data identification unit 2. The operating mode of the identification unit 2, ie, the mode of reference point, reference hex designation, graphic input, etc., is determined.

The coordinate data identification unit 2 stores the given time series coordinate data in the memory 3.4 and the tilt detection unit 5 according to the operation mode.
Or output to the figure identification section 6.

The figure identification unit 6 identifies the type of the drawn figure based on the given time series coordinate data, and according to the identification result,
The graphic data is output to the outside of the device or to the straight line identification section 7.

The inclination detection section 5 detects the inclination of a straight line based on the given data and outputs it to the coordinate data identification section 2 or the straight line identification section 7. The straight line identifying unit 7 identifies the drawn line segment as a proper straight line based on the data given from the inclination detecting unit 5 and the data read from the memories 3 and 4.

FIG. 2 is a schematic diagram illustrating the principle of the figure recognition method using the apparatus of the present invention. In the figure, a is a handwritten line segment, θa is its slope, b is a distant point where the line segment converges in perspective,
C is a straight line connecting the starting point S of the handwritten line segment and a distant point,
θC is its slope, d is a straight line having a preset slope of θC, and dθ is the angular range in each direction of the handwritten line segment (where it can be recognized that the slope is equal to the slope of the reference straight line).

In Figure 2, since (θc-dθ)≦θa≦(θC+dθ), the slope of handwritten line segment a is recognized as equal to θC, and the handwritten line segment is recognized as a correct straight line based on the perspective law. Ru.

A figure recognition method in the figure recognition apparatus configured as above will be explained. The handwritten figure input section 1 includes an input pen that moves on the figure input surface! It traces are detected as time series data on X-y coordinates, and the detected coordinate data is provided to the coordinate data identification section 2. When the input pen presses a mode designated area provided on the input surface of the handwritten figure input section 1, the coordinate data identification section 2 switches to an operation mode according to the mode of the designated area.

For example, when switching to an operation mode that specifies a distant point when drawing a three-dimensional figure based on perspective, the coordinate data identification unit 2 determines the first coordinate point (starting point) of the time-series coordinate data given thereafter. It is detected as a far point, and its coordinate values are stored in the memory 3.

In addition, when specifying a straight line with a constant slope as a reference straight line, the coordinate data identification unit 2 provides the coordinate data of the starting point and end point of the line segment given thereafter to the slope detection unit 5, and the slope detection unit 5 The slope of the straight line is determined from the obtained coordinate data and provided to the coordinate data identification section 2, and the coordinate data identification section 2 stores the provided data in the memory 4. In addition, memory 4
can store the slopes of a plurality of straight lines as the slopes of the reference straight line.

Furthermore, when a figure is input, the coordinate data identification unit 2 inputs the time-series coordinate data given thereafter to the figure identification unit 6.
give to The figure identification unit 6 detects the features of the figure, such as the bending point of the input bend, from the given coordinate data, and detects the type of the figure, such as a circle, triangle, square, straight line, etc. If the detection result is a figure other than a straight line, for example a circle, data such as a type code identifying it as a circle, the center coordinates of the circle, 2 the radius of the circle, etc. are output to the outside of the device.

On the other hand, if the detection result is a straight line, the leading data (starting point) and the final data (ending point) of the time-series coordinate data are provided to the straight line identification unit 7. The straight line identification section 7 provides coordinate data of the given starting point and end point to the inclination detecting section 5, and receives and receives the inclination data detected by the inclination detecting section 5. Next, the straight line identification section 7
The coordinate data of the starting point and the distant point stored in the memory 3 is given to the inclination detecting section 5 to determine the inclination of the straight line connecting both points, and the inclination data of the straight line is received.

In addition, the straight line identification unit 7 stores the slope data of the line segment drawn on the input surface in the memory 4 as 0゛ (horizontal axis), 90' (vertical axis), the slope of the straight line connecting the starting point and the far point. The slope is compared with the slope of the reference straight line drawn, which slope is closest is detected, and that slope is set as the slope of the drawn line segment.

Furthermore, the end point of the drawn line segment is projected perpendicularly to the straight line with the set inclination, and the projected point is reset as the end point of the drawn straight line. Note that the starting point of the drawn line segment remains unchanged.

On the other hand, if a reference straight line close to the slope of the drawn line segment is not detected, the slope detected from the coordinate data of the starting point and end point of the drawn straight line is directly set as the slope of the straight line,
The starting point and ending point are also left unchanged.

The straight line identification unit 7 is the starting point obtained as described above.

The end point is given to the figure identification section 6. The figure identification unit 6 outputs the type code identifying a straight line and the coordinate data of the start point and end point to the outside of the device as a recognition result of the drawn line segment.

Next, based on the flowchart shown in FIG. 3, the operation of recognizing a three-dimensional figure consisting of straight lines drawn based on perspective will be explained. In addition, the coordinate values of the distant point where the line segment of the solid figure converges, the allowable angle dθ in the upward direction where the slope can be determined to be equal, and the coordinate values of the start and end points of M reference straight lines with appropriate angles specified. must be registered in advance.

First, an initial value "0" is set to a flag F indicating whether a straight line with a slope that responds to the slope of a handwritten line segment is stored in advance (1).Next, the slope θa of the handwritten line segment a The difference θ between and the slope Oo of the horizontal axis is calculated (2). It is necessary to judge whether the calculated difference θ in the slope is larger or smaller than the predetermined angle dθ3). If the difference is small, that is, the stop of the handwritten line segment is almost equal to the horizontal axis, the flag F is set to 1", and θ1 is set to 1". The difference in inclination θ is set to 0° and θ2 on the horizontal axis, which serves as a comparison standard4), and the comparison with the vertical axis is omitted and the process moves to the next comparison.

On the other hand, if the difference in inclination θ is larger than the predetermined angle dθ, that is, if it is not close to the horizontal axis, then the inclination of the vertical axis is 90
Calculate the difference θ between the two degrees (5). It is necessary to judge whether the calculated difference θ in the inclination is larger or smaller than the predetermined angle dθ6). If the difference is small, the flag F is set to “1”. Set the difference θ7)
, move on to the next comparison.

Next, the difference θ between the slope θb of the straight line connecting the starting point S of the handwritten line segment and the far point S and the slope θa of the handwritten line segment is calculated (8). It is necessary to determine whether the calculated difference θ in the inclination is larger or smaller than the predetermined angle dθ9), and if the difference is small, the flag F is “
0'', the flag F is set to 61'', θ1 is set to dθ, and θ2 is set to the slope difference θ (00).

In addition, already (if a straight line with almost equal 'F' is detected and the flag F is "1", compare θ2 with θ and 1)), θ
If is smaller than θ2, the flag F remains unchanged, and θ1 is set to the current slope θb, and θ2 is set to the slope difference θ. On the other hand, if θ is larger than θ2, flag F is set.

θ1. θ2 is left as is and the process moves to the next comparison.

Next, comparison with M reference straight lines is performed sequentially, and as described above, if a reference straight line whose slope difference θ is less than or equal to dθ is detected,
Compare the difference θ and 02, and if θ is smaller than θ2, θ
2 is updated, and the reference straight line with the minimum difference in slope is detected.

As a result of the comparison, if a reference straight line that has been approximated is detected, the slope of the handwritten line segment is set to 01, and the end point of the handwritten line segment is vertically projected onto the straight line with a slope of 01 to create a straight line. 12), and the drawn line segment is recognized as a straight line based on perspective.

Further, as a result of the comparison, if a reference straight line with an approximate slope is not detected, the drawn line segment is recognized as a straight line with a slope θa (13).

Figure 4 ta+~(dl is a conceptual diagram showing a state in which each straight line is set according to the procedure described above, and (el is a conceptual diagram showing a state in which a handwritten figure is recognized as a correct three-dimensional figure based on the perspective law as a result of the setting. .

In addition, in this example, the procedure for recognizing a three-dimensional figure based on perspective has been explained, but it is also possible to recognize a group of hand-drawn straight lines as a group of straight lines having a certain slope using the same principle. . FIG. 5 is a conceptual diagram showing such a recognition state.
As a result of recognizing l 32 + 33 based on the specified reference straight lines d,, d2 having a constant slope, (bl
It can be recognized as a three-dimensional figure consisting of a group of mutually parallel straight lines as shown in .

〔Effect of the invention〕

When drawing a three-dimensional figure based on perspective, the figure recognition device of the present invention recognizes a line segment drawn with an inclination close to a straight line toward a distant point where the line segments converge as an accurate straight line based on perspective. Recognizable. Furthermore, a line segment drawn with an inclination close to a group of straight lines having a constant slope can be recognized as a three-dimensional figure made up of a group of straight lines with a predetermined slope. Therefore, even if a strictly accurate figure is not drawn, it is recognized as an accurate three-dimensional figure in accordance with a predetermined law, which has the excellent effect of facilitating figure input work.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a figure recognition device according to the present invention, FIG. 2 is a conceptual diagram explaining the principle of figure recognition, and FIG.
The figure is a flowchart showing the procedure of figure recognition, and FIGS. 4 and 5 are conceptual diagrams showing the state of figure recognition. 1... Handwritten figure input unit 2... Coordinate data identification unit 3.4... Memory 5... Tilt detection unit 6... Figure identification unit 7... Straight line identification unit Patent Applicant: Sanyo Electric Noboru Kono, Patent Attorney, Agent Co., Ltd. Figure 90 degree view (a) (b) (C) Figure (a) Figure

Claims (1)

[Claims] (1) In a device that recognizes figures drawn on the input surface, a means for predetermining a straight line with a predetermined slope as a reference straight line, and comparing the slope of the reference straight line with the slope of the drawn line segment. and means for recognizing the drawn line segment as a straight line having the same slope as the reference straight line, if the difference in slope between the reference straight line and the drawn line segment is less than or equal to a predetermined value as a result of the comparison. A figure recognition device characterized by: