Real-time handwriting recognition method, device and system

Abstract

The present invention relates to the field of handwriting recognition, and in particular to a real-time handwriting recognition method, device and system. The method comprises: monitoring an infrared receiving end that has not received an infrared signal and determining a mark point and then determining a continuous real-time handwriting; determining the tangent direction of the mark point of the real-time handwriting and determining the turning point of the real-time handwriting; if there are two or more turning points, judging whether the real-time handwriting is a stroke in the stroke library, if so, displaying the real-time handwriting on an electronic display board; if not, dividing the real-time handwriting into several sub-trajectories; selecting a sub-trajectory according to the time sequence of the formation of the sub-trajectory, if the sub-trajectory is a continuous stroke, if so, hiding the sub-trajectory and updating the real-time handwriting; when all the sub-trajectories are judged, displaying the real-time handwriting on the electronic display board; if there are no two or more turning points, displaying the real-time handwriting on the electronic display board. The present invention solves the problem of inaccurate real-time handwriting recognition.

Description

Technical Field

[0001] The present invention relates to the field of handwriting recognition, and in particular to a real-time handwriting recognition method, device and system. Background Art

[0002] Blackboard is a common writing medium in classrooms. With the development of science and technology, a variety of intelligent blackboard devices that combine handwriting blackboards and multimedia devices have appeared on the market. Among them, there is such an intelligent blackboard device, which is provided with several groups of crossed infrared rays on the handwriting blackboard, and can recognize handwriting on the handwriting blackboard through infrared rays so that the handwriting on the handwriting blackboard can be displayed on the multimedia device in real time.

[0003] At present, the method used for identifying handwriting on a handwriting blackboard equipped with infrared rays is to determine the landing point according to the blocked infrared rays, and determine the real-time motion trajectory according to the combination of the landing points to determine the real-time handwriting.

[0004] Since the recognition plane formed by infrared rays and the writing plane of the writing blackboard are not the same plane, the recognition plane is slightly higher than the writing plane. During the writing process, although the pen tip leaves the writing plane, it is still moving on the recognition plane and will be recognized as writing handwriting. Therefore, the phenomenon of connected strokes of the writing is more serious, which may lead to errors in the recognition of some strokes and the problem of inaccurate real-time handwriting recognition. Summary of the invention

[0005] Based on this, it is necessary to provide a real-time handwriting recognition method, device and system to address the above problems.

[0006] The embodiment of the present invention is implemented as follows: a real-time handwriting recognition method, the real-time handwriting recognition method comprising:

[0007] S101, monitoring the infrared receiving end that has not received the infrared signal;

[0008] S102, determining a mark point according to the infrared receiving end that does not receive the infrared signal and then determining a continuous real-time handwriting;

[0009] S103, determining the tangent direction of the marking point of the real-time handwriting;

[0010] S104, determining the turning point of the real-time handwriting according to the tangent direction of the marking point;

[0011] S105, determining whether there are two or more turning points, if so, determining whether the real-time handwriting is a stroke in the stroke library, if so, displaying the real-time handwriting on the electronic display board;

[0012] S106, if the real-time handwriting is not a stroke in the stroke library, dividing the real-time handwriting into a plurality of sub-trajectories according to the turning points;

[0013] S107, selecting a sub-track according to the time sequence of the sub-tracks, and determining whether the sub-track is a connected stroke, if so, hiding the sub-track and updating the real-time handwriting;

[0014] S108, repeat S107 until all sub-trajectories are judged, and the real-time handwriting is displayed on the electronic display board;

[0015] S109: If there are not two or more turning points, the real-time handwriting is displayed on the electronic display board.

[0016] In one embodiment, the present invention provides a real-time handwriting recognition device, the real-time handwriting recognition device comprising:

[0017] The infrared signal monitoring module is used to monitor the infrared receiving end that has not received the infrared signal;

[0018] A real-time handwriting determination module is used to determine a marking point according to an infrared receiving end that does not receive an infrared signal and then determine a continuous real-time handwriting;

[0019] A tangent direction determination module is used to determine the tangent direction of the marking point of the real-time handwriting;

[0020] A turning point determination module is used to determine the turning point of the real-time handwriting according to the tangent direction of the marking point;

[0021] The first display module is used to determine whether there are two or more turning points, and if so, determine whether the real-time handwriting is a stroke in the stroke library, and if so, display the real-time handwriting on the electronic display board;

[0022] A sub-track determination module is used to divide the real-time handwriting into a plurality of sub-tracks according to the turning points if the real-time handwriting is not a stroke in the stroke library;

[0023] The real-time handwriting updating module is used to select a sub-track according to the time sequence of the sub-track formation, and determine whether the sub-track is a connected stroke. If so, the sub-track is hidden and the real-time handwriting is hidden and updated;

[0024] A second display module is used to repeatedly update the real-time handwriting module until all sub-trajectories are judged, and display the real-time handwriting on the electronic display board;

[0025] The third display module is used to display the real-time handwriting on the electronic display board if there are not two or more turning points.

[0026] In one embodiment, the present invention provides a real-time handwriting recognition system, the real-time handwriting recognition system comprising: an electronic display board, a handwriting display board and a computer device;

[0027] The electronic display board is connected to the computer device and is used to display the real-time handwriting of the handwriting display board;

[0028] The handwriting display board is connected to the computer device and is used for users to write to generate real-time handwriting;

[0029] The computer device is used to execute the steps of the above-mentioned real-time handwriting recognition method.

[0030] A real-time handwriting recognition method provided by an embodiment of the present invention monitors an infrared receiving end that does not receive an infrared signal; determines a mark point according to the infrared receiving end that does not receive an infrared signal and then determines a continuous real-time handwriting; determines the tangent direction of the mark point of the real-time handwriting; determines the turning point of the real-time handwriting according to the tangent direction of the mark point; determines whether there are two or more turning points, and if so, determines whether the real-time handwriting is a stroke in the stroke library, and if so, displays the real-time handwriting on an electronic display board; if the real-time handwriting is not a stroke in the stroke library, divides the real-time handwriting into several sub-tracks according to the turning point; selects a sub-track according to the time sequence of the formation of the sub-track, determines whether the sub-track is a continuous stroke, and if so, hides the sub-track and updates the real-time handwriting; when all the sub-tracks are judged, the real-time handwriting is displayed on the electronic display board; if there are no two or more turning points, the real-time handwriting is displayed on the electronic display board. The present invention identifies the continuous real-time handwriting as a continuous stroke every time a continuous real-time handwriting is determined, and hides the sub-track identified as a continuous stroke. In this way, the handwriting that is recognized because the pen tip leaves the writing plane during the writing process but is still on the recognition plane is hidden and filtered, so that the real-time trajectory of this part will not be displayed on the electronic display board, solving the problem of inaccurate real-time handwriting recognition. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A flowchart of real-time handwriting recognition in one embodiment;

[0032] Figure 2 A logic diagram of real-time handwriting recognition in one embodiment;

[0033] Figure 3 is a structural block diagram of a real-time handwriting recognition device in one embodiment;

[0034] Figure 4 is a structural block diagram of a real-time handwriting recognition system in one embodiment;

[0035] Figure 5 A schematic diagram of the writing display board;

[0036] Figure 6 FIG. 4 is a block diagram of the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0038] It is understood that the terms "first", "second", etc. used in the present invention may be used herein to describe various elements, but unless otherwise specified, these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, a first xx script may be referred to as a second xx script, and similarly, a second xx script may be referred to as a first xx script without departing from the scope of the present invention.

[0039] like Figure 1 , Figure 2 As shown, in one embodiment, a real-time handwriting recognition method is proposed, which may specifically include the following steps:

[0040] S101, monitoring the infrared receiving end that has not received the infrared signal;

[0041] S102, determining a mark point according to the infrared receiving end that does not receive the infrared signal and then determining a continuous real-time handwriting;

[0042] S103, determining the tangent direction of the marking point of the real-time handwriting;

[0043] S104, determining the turning point of the real-time handwriting according to the tangent direction of the marking point;

[0044] S105, determining whether there are two or more turning points, if so, determining whether the real-time handwriting is a stroke in the stroke library, if so, displaying the real-time handwriting on the electronic display board;

[0045] S106, if the real-time handwriting is not a stroke in the stroke library, dividing the real-time handwriting into a plurality of sub-trajectories according to the turning points;

[0046] S107, selecting a sub-track according to the time sequence of the sub-tracks, and determining whether the sub-track is a connected stroke, if so, hiding the sub-track and updating the real-time handwriting;

[0047] S108, repeat S107 until all sub-trajectories are judged, and the real-time handwriting is displayed on the electronic display board;

[0048] S109: If there are not two or more turning points, the real-time handwriting is displayed on the electronic display board.

[0049] In this embodiment, the writing whiteboard is a carrier for users to write on the blackboard. There are infrared modules on the plane of the writing whiteboard. For example, several groups of infrared modules are arranged in the horizontal direction, and several groups of infrared modules are arranged in the vertical direction. The infrared modules include an infrared transmitting end and an infrared receiving end. When not blocked, the infrared receiving end receives the infrared signal of the corresponding infrared transmitting end. If the user is in the process of writing, the pen tip will touch the plane of the writing whiteboard. At this time, the pen tip will block part of the infrared signal, so there will be an infrared receiving end that does not receive the infrared signal.

[0050] In this embodiment, only one marking point is determined at one moment, and the marking point is not necessarily a unique point, but may be a circular area formed by a collection of multiple points.

[0051] In this embodiment, each time a continuous real-time handwriting segment is determined, the real-time handwriting segment is judged as connected. Real-time handwritings of different segments will not affect each other.

[0052] In this embodiment, the real-time handwriting can be a straight line segment, a curved line segment, a combination of a straight line segment and a curved line segment, or a combination of different curved lines. Each segment of the real-time handwriting can have a sharp point, but cannot have a breakpoint. Once a breakpoint appears, the breakpoint distinguishes the real-time handwriting of the two segments.

[0053] In this embodiment, the turning point does not include the start point and the end point of the real-time handwriting.

[0054] In this embodiment, if there is no turning point, then the real-time handwriting, whether it is a stroke or other content, such as a circle, symbol, or line, is the content written by the user. At this time, there is no need to judge the real-time handwriting, and it can be directly displayed. Therefore, it is not only text that is displayed, but also symbols, lines, etc. If there is a turning point, the real-time handwriting is divided into two parts. The extra part may be part of the stroke. For example, there is a turning point in the stroke of the left and right strokes. There is no need to judge the real-time handwriting, and it can be directly displayed; the extra part may also be caused by the user's connected strokes, but the connected strokes are disconnected from the next real-time handwriting, and are clearly distinguished from the next stroke, which does not affect the overall viewing experience of the font. Therefore, there is no need to judge the real-time handwriting, and it can be directly displayed.

[0055] In the present embodiment, for example, the real-time handwriting corresponding to the stroke of horizontal fold, fold, fold hook has four turning points, and the corresponding strokes can be determined at this time, so there is no need to judge whether the real-time handwriting has a connected stroke, and the corresponding strokes can be directly determined. The stroke library is a database of strokes, which includes basic strokes such as horizontal, vertical, left-falling stroke, right-falling stroke, dot, lift, vertical hook, arc hook, spear hook, horizontal hook, vertical bend, vertical hook, vertical lift, horizontal hook, horizontal fold, horizontal analysis hook, horizontal left-falling stroke, left-falling stroke, left-falling stroke dot, horizontal fold hook, vertical fold, vertical fold hook, horizontal fold lift, horizontal fold fold left-falling stroke, horizontal left-falling stroke hook, horizontal fold fold hook, horizontal bend, vertical fold left-falling stroke and the like.

[0056] In this embodiment, the real-time handwriting is not a stroke in the stroke library, which means that the real-time handwriting is composed of several strokes and connecting strokes between the strokes, for example, two strokes and connecting strokes between the two strokes.

[0057] In this embodiment, the real-time handwriting has a starting point and an end point, and the turning point does not include the starting point and the end point, so the first sub-track is from the starting point to the first turning point, and the last sub-track is from the last turning point to the end point. There are at least three sub-tracks.

[0058] In this embodiment, the real-time track is determined during the writing process according to the infrared signal reception of the infrared receiving end, so there is a time sequence. The appearance of the marking points has a time sequence. The formation of the sub-track is essentially a combination of several marking points, so the formation of the sub-track also has a time sequence. All the marking points on the first formed sub-track are generated before all the marking points on the later formed sub-track.

[0059] In this embodiment, each time a sub-track is selected in S107 and S108, each sub-track is judged only once, so the sub-tracks are selected according to the time sequence of the sub-tracks until all the sub-tracks are judged. If the selected sub-track is not a connected stroke, the next sub-track is selected according to the time sequence of the sub-tracks to continue judging whether it is a connected stroke.

[0060] In this embodiment, the real-time handwriting display on the electronic display board is slower than the writing process of the real-time handwriting. For example, when writing the second stroke, the real-time handwriting display of the first stroke begins on the electronic display board.

[0061] A real-time handwriting recognition method provided by an embodiment of the present invention monitors an infrared receiving end that does not receive an infrared signal; determines a mark point according to the infrared receiving end that does not receive an infrared signal and then determines a continuous real-time handwriting; determines the tangent direction of the mark point of the real-time handwriting; determines the turning point of the real-time handwriting according to the tangent direction of the mark point; determines whether there are two or more turning points, and if so, determines whether the real-time handwriting is a stroke in the stroke library, and if so, displays the real-time handwriting on an electronic display board; if the real-time handwriting is not a stroke in the stroke library, divides the real-time handwriting into several sub-tracks according to the turning point; selects a sub-track according to the time sequence of the formation of the sub-track, determines whether the sub-track is a continuous stroke, and if so, hides the sub-track and updates the real-time handwriting; when all the sub-tracks are judged, the real-time handwriting is displayed on the electronic display board; if there are no two or more turning points, the real-time handwriting is displayed on the electronic display board. The present invention identifies the continuous real-time handwriting as a continuous stroke every time a continuous real-time handwriting is determined, and hides the sub-track identified as a continuous stroke. In this way, the handwriting that is recognized because the pen tip leaves the writing plane during the writing process but is still on the recognition plane is hidden and filtered, so that the real-time trajectory of this part will not be displayed on the electronic display board, solving the problem of inaccurate real-time handwriting recognition.

[0062] In one embodiment, the step of determining a mark point based on an infrared receiving end that does not receive an infrared signal and then determining a continuous real-time handwriting includes:

[0063] Determine the infrared receiving end A that does not receive the infrared signal at the same time;

[0064] Determine a marking point according to the preset coordinates of the infrared receiving terminal A;

[0065] Each time a marking point is determined, it is determined whether a new marking point is determined within a first preset time, and if not, the marking point is determined as the end point of a continuous real-time handwriting;

[0066] If a new marking point is determined within the first preset time, determine whether the distance between the marking point and the new marking point is greater than the preset distance, and if so, determine the marking point as the end point of a continuous real-time handwriting;

[0067] The end point and the unconnected marking points before the end point are connected in time sequence to obtain a continuous real-time handwriting.

[0068] In this embodiment, the preset coordinates of the infrared receiving end depend on the position of the infrared module. For example, if the receiving end of the infrared module is set on the left and bottom sides of the writing whiteboard, a two-dimensional coordinate system is established according to the left and bottom sides of the writing whiteboard. In this way, all the infrared receiving ends on the left side represent the y-axis, and the preset coordinates of the infrared receiving end on the left side can be (0, y n ), all the infrared receiving ends on the lower side represent the x-axis, and the preset coordinates of the infrared receiving ends on the lower side can be (x n , 0). Theoretically, if the pen tip is thin enough or the grid composed of infrared signals is too wide, then there are only two infrared receiving terminals A that do not receive infrared signals at the same time, one on the left and one on the bottom. At this time, a mark point is determined according to the preset coordinates of the infrared receiving terminal A, which essentially determines the coordinates of the mark point, that is, (x n ,y n ) is the marking point. In fact, the pen tip may block more than two infrared receiving ends A at the same time, but the number of infrared receiving ends A blocked must be even, with half of the infrared receiving ends A on the left and the bottom. At this time, multiple coordinate points are determined, and the marking point is the area surrounded by multiple coordinate points. In this way, the coordinates of the midpoint of the area surrounded by multiple coordinate points can be determined as the coordinates of the marking point.

[0069] In this embodiment, the first preset time can be set to any value in the range of 0.1-1S. If no new marking point is generated within the first preset time, it can be considered as a pen break. For example, the pen stops after writing a word. If the first preset time is not determined, the last real-time handwriting cannot be obtained.

[0070] In this embodiment, the preset distance can be set to 2-3 times the diagonal of the smallest grid of the infrared grid composed of infrared signals. Even if the marking point is the center point of an area composed of multiple points, if it is a continuous real-time handwriting, the center point is also an adjacent coordinate point.

[0071] In this embodiment, the connected marking points are the previous continuous real-time handwriting, so the unconnected marking points are connected in time sequence, and the first marking point in the time sequence is the starting point of this continuous real-time handwriting.

[0072] In this embodiment, the marking points are connected because what are determined are coordinate points on the infrared grid, and the grid needs to be hollow and needs to be connected with line segments.

[0073] In one embodiment, determining the tangent direction of the marking point of the real-time handwriting includes:

[0074] Determine the curve function of real-time handwriting;

[0075] For each marked point, the curve function is differentiated once at the marked point to obtain the tangent slope of the marked point;

[0076] Determine whether the tangent slope of the marked point exists, and if so, determine the tangent of the marked point according to the tangent slope of the marked point;

[0077] Determine the tangent direction of the marking point according to the tangent of the marking point and the instantaneous direction of the marking point in the real-time handwriting;

[0078] If the tangent slope of the marked point does not exist, the direction of the line connecting the previous marked point of the real-time handwriting to the marked point is recorded as the tangent direction of the marked point.

[0079] In this embodiment, the curve function of the real-time handwriting can be determined by existing technology, such as existing software such as MATLAB and Desmos. The curve function can be a piecewise function. The purpose of determining the curve function of the real-time handwriting is to perform a derivative of the curve function and then determine the tangent slope of the marked point. Existing software such as MATLAB and Desmos can also directly determine the tangent slope of the marked point on the real-time handwriting without determining the curve function of the real-time handwriting. Therefore, determining the curve function of the real-time handwriting is only an intermediate process and can be omitted.

[0080] In this embodiment, the situation where the tangent slope of the marking point does not exist may be that the part of the real-time handwriting where the marking point is located is perpendicular to the horizontal direction, that is, the x-axis; it may also be a sharp point.

[0081] In this embodiment, the tangent of the marked point is determined according to the tangent slope of the marked point. The tangent slope of the marked point is the k value of the slope-intercept equation. The coordinates of the marked point can be substituted into the slope-intercept equation to determine the b value, so that the straight line of the slope-intercept equation can be determined, and the straight line is the tangent of the marked point. The marked point divides the straight line into two rays, where the instantaneous direction of the marked point in the real-time handwriting must be consistent with the direction of one of the rays, and the direction of the ray with the same direction is the tangent direction of the marked point.

[0082] In one embodiment, determining the turning point of the real-time handwriting according to the tangent direction of the marking point includes:

[0083] For each marked point, determine the unit tangent vector of the marked point according to the tangent direction of the marked point;

[0084] Determine a first angle formed by a unit tangent vector of the marking point and a unit tangent vector of a next marking point of the real-time handwriting;

[0085] It is determined whether the first angle is greater than a first preset angle, and if so, the marking point is determined as a turning point of the real-time handwriting.

[0086] In this embodiment, the unit tangent vector is a vector with a length of 1 and a direction that is the tangent direction.

[0087] In this embodiment, the turning point represents that the curve has undergone a large turning, so the first preset angle can be set to 45° to 60°.

[0088] In this embodiment, if the first included angle is not greater than the first preset angle, no operation is performed.

[0089] In one embodiment, selecting a sub-trajectory according to the time sequence of the sub-trajectories and determining whether the sub-trajectory is a connected stroke includes:

[0090] Select a sub-trajectory A according to the time sequence of the sub-trajectories;

[0091] Fit sub-trajectory A to obtain the straight line segment corresponding to sub-trajectory A;

[0092] Determine the line segment direction of the line segment corresponding to the sub-trajectory A according to the projection point of the marked point on the line segment corresponding to the sub-trajectory A and determine the unit vector of the line segment direction;

[0093] Determine whether sub-track A has a previous sub-track B in the time sequence of sub-track formation, if so, determine whether the previous sub-track B of sub-track A in the time sequence of sub-track formation is a connected stroke, if so, determine sub-track A as not a connected stroke;

[0094] If the previous sub-trajectory B of sub-trajectory A in the time sequence of sub-trajectory formation is not a connected stroke, determine a second angle formed by a unit vector of the line segment direction of the straight line segment corresponding to sub-trajectory A and a unit vector of the line segment direction of the straight line segment corresponding to sub-trajectory B;

[0095] Determine whether the second angle is greater than a second preset angle. If not, determine that the sub-trajectory A is not a connected stroke. If so, determine a third angle formed by a unit vector of the line segment direction of the straight line segment corresponding to the sub-trajectory A and the preset vector.

[0096] Determine whether the third angle is greater than a third preset angle, if so, determine the sub-trajectory as a connected stroke, if not, determine the sub-trajectory A as not a connected stroke;

[0097] If sub-track A does not have a previous sub-track B in the time sequence of sub-track formation, sub-track A is determined to be not a connected stroke.

[0098] In this embodiment, there are many ways to fit the sub-trajectory A to obtain the straight line segment corresponding to the sub-trajectory A, such as polynomial fitting, least squares method, linear regression, etc.

[0099] In this embodiment, the generation of the marking points has a chronological order. Therefore, the chronological order of the projection points can be consistent with the marking points corresponding to the projection points. In this way, the generation of the projection points also has a chronological order. Therefore, the line segment direction of the straight line segment corresponding to the sub-trajectory A can be determined. For example, if the projection points are generated from left to right, then the line segment direction of the straight line segment corresponding to the sub-trajectory A is from left to right.

[0100] In this embodiment, if the sub-trajectory A is the first sub-trajectory in the real-time handwriting, then the sub-trajectory A is a stroke and is determined not to be a connected stroke.

[0101] In this embodiment, the connected stroke is in the middle of two strokes. Therefore, if the sub-trajectory B is a connected stroke, the sub-trajectory A must not be a connected stroke. If the sub-trajectory B is not a connected stroke, then the sub-trajectory A may be a part of a stroke or a connected stroke. For example, the first stroke and the second stroke of the character "司" form a connected stroke. At this time, the second sub-trajectory in the first stroke is not a connected stroke. Therefore, the second preset angle can be set to any angle value between 90° and 100°.

[0102] In this embodiment, for example, the first stroke and the second stroke of the character "尔" are connected, but there is no connected stroke between them. At this time, for the second sub-trajectory, it needs to be determined not to be a connected stroke. Therefore, the preset vector is the unit horizontal vector, and the third preset angle can be set to 0° to 15°. In this way, this situation can be excluded. Generally, there is no horizontal connected stroke in connected strokes.

[0103] In one embodiment, the displaying the real-time handwriting on the electronic display board includes:

[0104] Determine an infrared ray network according to the infrared signals sent by the infrared emission end, and determine the first plane according to the infrared ray network;

[0105] Establish a second plane on the electronic display board that is the same as the first plane;

[0106] Perform point-to-point correspondence between the first plane and the second plane;

[0107] Determine the specific position of the real-time handwriting on the electronic display board according to the correspondence between the first plane and the second plane and the specific position of the real-time handwriting on the first plane, and display it.

[0108] In this embodiment, the area of the second plane is the same as that of the first plane, and the second plane can be at any position on the electronic display board.

[0109] In this embodiment, to perform point-to-point correspondence between the first plane and the second plane, only the left side of the first plane needs to be corresponded to the left side of the second plane, and the lower side of the first plane needs to be corresponded to the lower side of the second plane.

[0110] In one embodiment, the step of displaying the real-time handwriting on the electronic display board further includes:

[0111] Determine the real-time handwriting on the electronic display board before a third preset time at every second preset time;

[0112] Determine the font of real-time handwriting;

[0113] For each font, determine whether the font can find the corresponding character C in the character database, and if so, determine all hidden sub-trajectories D in the real-time handwriting formed by the font;

[0114] For each sub-track D, determine whether there is a part of the connecting line in the sub-track D that corresponds to the pen tip of the stroke of the character C. If so, display the part of the connecting line in the sub-track D that corresponds to the pen tip of the stroke of the character C.

[0115] If the font cannot find the character C corresponding to the font in the character database, all the hidden sub-trajectories D of the real-time handwriting composed of the font will be displayed.

[0116] In this embodiment, the second preset time can be set to any value within 1-3 seconds, and 1-3 seconds can complete the writing of a character. The third preset time can be the same as the second preset time. For example, the second preset time is 2 seconds, and the third preset time is 2 seconds. Then at the 6th second, the real-time handwriting on the electronic display board before 2 seconds is determined, that is, the real-time handwriting on the electronic display board at the 4th second. At this time, the real-time handwriting displayed on the electronic display board constitutes a font.

[0117] In this embodiment, there are many ways to determine the font composed of real-time handwriting, for example, determine an adaptive recognition area, and determine the real-time handwriting within the recognition area as a font, similar to image recognition of text. It is worth noting that the font composed of real-time handwriting is not necessarily a text. For example, errors occur during the recognition of connected strokes and the strokes are hidden, resulting in unformed text, or the written text is too abstract, resulting in errors in connected stroke recognition. Therefore, it is necessary to perform text recognition on the completed real-time handwriting to correct errors.

[0118] In this embodiment, there are two types of error correction. One is that the font corresponding to the text C cannot be found in the text database. In this case, it may be that the written text is too abstract, resulting in an error in the recognition of connected strokes. For example, the user writes a cursive font or a special symbol. It may also be that normal strokes are recognized as connected strokes, resulting in unformed text. In this case, all the hidden sub-trajectories D of the real-time handwriting formed by this font are directly displayed, that is, the real-time handwriting is displayed as it was originally. Another situation is that the text is recognized, but the pen tip is hidden because it is in the same sub-trajectory as the connected stroke. For example, the first stroke and the second stroke of the character "司" form a connected stroke, and the hook in the horizontal fold hook of the first stroke is hidden together in the sub-trajectory of the connected stroke. At this time, although the font can be compared and matched with the character "司", the hook in the horizontal fold hook is missing when displayed, and error correction is required. In this case, the part of the sub-trajectory D corresponding to the pen tip of the stroke of the text C is displayed by connecting the lines.

[0119] As Figure 3 shown, in one embodiment, a real-time handwriting recognition device is provided, which may specifically include:

[0120] An infrared signal monitoring module, which is used to monitor the infrared receiving end that does not receive an infrared signal;

[0121] A real-time handwriting determination module, which is used to determine a marker point based on the infrared receiving end that does not receive an infrared signal, and then determine a continuous real-time handwriting;

[0122] A tangent direction determination module, which is used to determine the tangent direction of the marker point of the real-time handwriting;

[0123] A turning point determination module, which is used to determine the turning points of the real-time handwriting according to the tangent direction of the marker point;

[0124] A first display module, which is used to determine whether there are two or more turning points. If so, determine whether the real-time handwriting is a stroke in the stroke library. If so, display the real-time handwriting on the electronic display board;

[0125] A sub-trajectory determination module, which is used to divide the real-time handwriting into several sub-trajectories according to the turning points if the real-time handwriting is not a stroke in the stroke library;

[0126] A real-time handwriting update module, which is used to select a sub-trajectory according to the time sequence formed by the sub-trajectories, determine whether the sub-trajectory is a connected stroke. If so, hide the sub-trajectory and update the real-time handwriting by hiding;

[0127] A second display module, which is used to repeat the real-time handwriting update module until all sub-trajectories are judged, and display the real-time handwriting on the electronic display board;

[0128] The third display module is used to display the real-time handwriting on the electronic display board if there are not two or more turning points.

[0129] In this embodiment, each module of the real-time handwriting recognition device is a modularization of the method part of the present invention. For the specific explanation of each module, please refer to the corresponding content of the method part of the present invention, and the embodiment of the present invention will not be repeated here.

[0130] like Figure 4 As shown, in one embodiment, a real-time handwriting recognition system is provided, which may specifically include: an electronic display board, a handwriting display board and a computer device;

[0131] The electronic display board is connected to the computer device and is used to display the real-time handwriting of the handwriting display board;

[0132] The handwriting display board is connected to the computer device and is used for users to write to generate real-time handwriting;

[0133] The computer device is used to execute the steps of the above-mentioned real-time handwriting recognition method.

[0134] In this embodiment, the electronic display board can be an all-in-one teaching machine, which integrates multiple technologies such as infrared touch technology, intelligent office teaching software, multimedia network communication technology, high-definition flat-panel display technology, etc. It integrates multiple devices such as projectors, electronic whiteboards, computers, televisions, touch functions, etc. into one multifunctional interactive teaching device, which upgrades the traditional display terminal into a full-featured human-computer interaction device.

[0135] In this embodiment, the computer device can be a hardware device or a cloud server. The computer device, the electronic display board and the handwriting display board are all provided with communication components to enable the computer device to communicate with the electronic display board and the handwriting display board.

[0136] A real-time handwriting recognition system provided by an embodiment of the present invention monitors an infrared receiving end that does not receive an infrared signal; determines a mark point according to the infrared receiving end that does not receive an infrared signal and then determines a continuous real-time handwriting; determines the tangent direction of the mark point of the real-time handwriting; determines the turning point of the real-time handwriting according to the tangent direction of the mark point; determines whether there are two or more turning points, and if so, determines whether the real-time handwriting is a stroke in the stroke library, and if so, displays the real-time handwriting on an electronic display board; if the real-time handwriting is not a stroke in the stroke library, divides the real-time handwriting into several sub-trajectories according to the turning point; selects a sub-trajectory according to the time sequence of the formation of the sub-trajectory, determines whether the sub-trajectory is a continuous stroke, and if so, hides the sub-trajectory and updates the real-time handwriting; when all the sub-trajectories are judged, the real-time handwriting is displayed on the electronic display board; if there are no two or more turning points, the real-time handwriting is displayed on the electronic display board. The present invention identifies the continuous strokes of the continuous real-time handwriting every time it determines a continuous real-time handwriting, and hides the sub-trajectory identified as a continuous stroke. In this way, the handwriting that is recognized because the pen tip leaves the writing plane during the writing process but is still on the recognition plane is hidden and filtered, so that the real-time trajectory of this part will not be displayed on the electronic display board, solving the problem of inaccurate real-time handwriting recognition.

[0137] like Figure 5 As shown, in one embodiment, the handwriting display board includes: a plurality of groups of first infrared modules, a plurality of groups of second infrared modules and a writing day shift;

[0138] The first infrared module includes an infrared transmitting end and an infrared receiving end, and is arranged in a first direction of the plane of the writing white class;

[0139] The second infrared module includes an infrared transmitting end and an infrared receiving end, and is arranged in the second direction of the plane of the writing white class;

[0140] The first infrared module and the second infrared module are used to recognize the real-time handwriting of the user when writing;

[0141] The writing day shift is used for users to write.

[0142] In this embodiment, the handwriting display board also includes plastic corners, an aluminum frame, right-angle irons, a printed circuit board (PCBA, Printed Circuit Board + Assembly), etc.

[0143] In this embodiment, the first direction may be a horizontal direction, and the second direction may be a vertical direction perpendicular to the horizontal direction. The first infrared module and the second infrared module are used in conjunction, that is, one determines the coordinates in the horizontal direction, and the other determines the coordinates in the vertical direction, thereby obtaining a coordinate point, which is the location of the pen tip. A two-dimensional coordinate system can be established with any vertex of the writing display board as the origin, the horizontal direction as the x-axis, and the vertical direction as the y-axis. Such a two-dimensional coordinate system can reflect the coordinate points determined by the first infrared module and the second infrared module.

[0144] In this embodiment, the first direction may also be a direction that forms an angle with the horizontal direction, and it only needs to keep the first direction and the second direction perpendicular.

[0145] Figure 6 FIG. 2 shows an internal structure diagram of a computer device in one embodiment. Figure 6 As shown, the computer device includes a processor, a memory, a network interface, an input device and a display screen connected via a system bus. Among them, the memory includes a non-volatile storage medium and an internal memory. The non-volatile storage medium of the computer device stores an operating system and may also store a computer program. When the computer program is executed by the processor, the processor can implement a real-time handwriting recognition method provided by an embodiment of the present invention. The internal memory may also store a computer program. When the computer program is executed by the processor, the processor can execute a real-time handwriting recognition method provided by an embodiment of the present invention. The display screen of the computer device may be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device may be a touch layer covering the display screen, or a button, trackball or touchpad provided on the housing of the computer device, or an external keyboard, touchpad or mouse, etc.

[0146] Those skilled in the art will understand that Figure 6 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present invention, and does not constitute a limitation on the computer device to which the solution of the present invention is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0147] In one embodiment, a real-time handwriting recognition device provided by an embodiment of the present invention can be implemented in the form of a computer program. The computer program can be used in Figure 6 The computer device shown in the figure is run. The memory of the computer device can store various program modules constituting the real-time handwriting recognition device, such as: Figure 3The infrared signal monitoring module, real-time handwriting determination module, tangent direction determination module, turning point determination module, first display module, sub-track determination module, real-time handwriting update module, second display module and third display module are shown. The computer program composed of each program module enables the processor to execute the steps of a real-time handwriting recognition method of each embodiment of the present invention described in this specification.

[0148] For example, Figure 6 The computer device shown can be Figure 3 The infrared signal monitoring module in the real-time handwriting recognition device shown executes step S101; the computer device can execute step S102 by determining the real-time handwriting module; the computer device can execute step S103 by determining the tangent direction module; the computer device can execute step S104 by determining the turning point module; the computer device can execute step S105 by the first display module; the computer device can execute step S106 by determining the sub-trajectory module; the computer device can execute step S107 by updating the real-time handwriting module; the computer device can execute step S108 by the second display module; the computer device can execute step S109 by the third display module.

[0149] In one embodiment, a computer device is provided, the computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the following steps are implemented:

[0150] S101, monitoring the infrared receiving end that has not received the infrared signal;

[0151] S102, determining a mark point according to the infrared receiving end that does not receive the infrared signal and then determining a continuous real-time handwriting;

[0152] S103, determining the tangent direction of the marking point of the real-time handwriting;

[0153] S104, determining the turning point of the real-time handwriting according to the tangent direction of the marking point;

[0154] S105, determining whether there are two or more turning points, if so, determining whether the real-time handwriting is a stroke in the stroke library, if so, displaying the real-time handwriting on the electronic display board;

[0155] S106, if the real-time handwriting is not a stroke in the stroke library, dividing the real-time handwriting into a plurality of sub-trajectories according to the turning points;

[0156] S107, selecting a sub-track according to the time sequence of the sub-tracks, and determining whether the sub-track is a connected stroke, if so, hiding the sub-track and updating the real-time handwriting;

[0157] S108, repeat S107 until all sub-trajectories are judged, and the real-time handwriting is displayed on the electronic display board;

[0158] S109: If there are not two or more turning points, the real-time handwriting is displayed on the electronic display board.

[0159] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the processor performs the following steps:

[0160] S101, monitoring the infrared receiving end that has not received the infrared signal;

[0161] S102, determining a mark point according to the infrared receiving end that does not receive the infrared signal and then determining a continuous real-time handwriting;

[0162] S103, determining the tangent direction of the marking point of the real-time handwriting;

[0163] S104, determining the turning point of the real-time handwriting according to the tangent direction of the marking point;

[0164] S105, determining whether there are two or more turning points, if so, determining whether the real-time handwriting is a stroke in the stroke library, if so, displaying the real-time handwriting on the electronic display board;

[0165] S106, if the real-time handwriting is not a stroke in the stroke library, dividing the real-time handwriting into a plurality of sub-trajectories according to the turning points;

[0166] S107, selecting a sub-track according to the time sequence of the sub-tracks, and determining whether the sub-track is a connected stroke, if so, hiding the sub-track and updating the real-time handwriting;

[0167] S108, repeat S107 until all sub-trajectories are judged, and the real-time handwriting is displayed on the electronic display board;

[0168] S109: If there are not two or more turning points, the real-time handwriting is displayed on the electronic display board.

[0169] It should be understood that, although each step in the flow chart of each embodiment of the present invention is shown in sequence according to the indication of the arrow, these steps are not necessarily performed in sequence according to the order indicated by the arrow. Unless there is a clear explanation in this article, the execution of these steps does not have strict order restrictions, and these steps can be performed in other orders. Moreover, at least a portion of the steps in each embodiment may include a plurality of sub-steps or a plurality of stages, and these sub-steps or stages are not necessarily performed at the same time, but can be performed at different times, and the execution order of these sub-steps or stages is not necessarily performed in sequence, but can be performed in turn or alternately with at least a portion of other steps or sub-steps or stages of other steps.

[0170] A person of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment method can be completed by instructing the relevant hardware through a computer program, and the program can be stored in a non-volatile computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided by the present invention can include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0171] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0172] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A real-time handwriting recognition method, characterized in that: The real-time handwriting recognition method comprises: S101, monitoring the infrared receiving end that has not received the infrared signal; S102, determining a mark point according to the infrared receiving end that does not receive the infrared signal and then determining a continuous real-time handwriting; S103, determining the tangent direction of the marking point of the real-time handwriting; S104, determining the turning point of the real-time handwriting according to the tangent direction of the marking point; S105, determining whether there are two or more turning points, if so, determining whether the real-time handwriting is a stroke in the stroke library, if so, displaying the real-time handwriting on the electronic display board; S106, if the real-time handwriting is not a stroke in the stroke library, dividing the real-time handwriting into a plurality of sub-trajectories according to the turning points; S107, selecting a sub-track according to the time sequence of the sub-tracks, and determining whether the sub-track is a connected stroke, if so, hiding the sub-track and updating the real-time handwriting; S108, repeat S107 until all sub-trajectories are judged, and the real-time handwriting is displayed on the electronic display board; S109, if there are not two or more turning points, displaying the real-time handwriting on the electronic display board; The step of selecting a sub-trajectory according to the time sequence of the sub-trajectories, and judging whether the sub-trajectory is a connected stroke, comprises: Select a sub-trajectory A according to the time sequence of the sub-trajectories; Fit sub-trajectory A to obtain the straight line segment corresponding to sub-trajectory A; Determine the line segment direction of the line segment corresponding to the sub-trajectory A according to the projection point of the marked point on the line segment corresponding to the sub-trajectory A and determine the unit vector of the line segment direction; Determine whether sub-track A has a previous sub-track B in the time sequence of sub-track formation, if so, determine whether the previous sub-track B of sub-track A in the time sequence of sub-track formation is a connected stroke, if so, determine sub-track A as not a connected stroke; If the previous sub-trajectory B of sub-trajectory A in the time sequence of sub-trajectory formation is not a connected stroke, determine a second angle formed by a unit vector of the line segment direction of the straight line segment corresponding to sub-trajectory A and a unit vector of the line segment direction of the straight line segment corresponding to sub-trajectory B; Determine whether the second angle is greater than a second preset angle. If not, determine that the sub-trajectory A is not a connected stroke. If so, determine a third angle formed by a unit vector of the line segment direction of the straight line segment corresponding to the sub-trajectory A and the preset vector. Determine whether the third angle is greater than a third preset angle, if so, determine the sub-trajectory as a connected stroke, if not, determine the sub-trajectory A as not a connected stroke; If sub-track A does not have a previous sub-track B in the time sequence of sub-track formation, sub-track A is determined to be not a connected stroke.

2. The real-time handwriting recognition method according to claim 1, characterized in that: The step of determining a mark point based on an infrared receiving end that does not receive an infrared signal and then determining a continuous real-time handwriting includes: Determine the infrared receiving end A that does not receive the infrared signal at the same time; Determine a marking point according to the preset coordinates of the infrared receiving terminal A; Each time a marking point is determined, it is determined whether a new marking point is determined within a first preset time, and if not, the marking point is determined as the end point of a continuous real-time handwriting; If a new marking point is determined within the first preset time, determine whether the distance between the marking point and the new marking point is greater than the preset distance, and if so, determine the marking point as the end point of a continuous real-time handwriting; The end point and the unconnected marking points before the end point are connected in time sequence to obtain a continuous real-time handwriting.

3. The real-time handwriting recognition method according to claim 1, characterized in that: The step of determining the tangent direction of the marking point of the real-time handwriting includes: Determine the curve function of real-time handwriting; For each marked point, the curve function is differentiated once at the marked point to obtain the tangent slope of the marked point; Determine whether the tangent slope of the marked point exists, and if so, determine the tangent of the marked point according to the tangent slope of the marked point; Determine the tangent direction of the marking point according to the tangent of the marking point and the instantaneous direction of the marking point in the real-time handwriting; If the tangent slope of the marked point does not exist, the direction of the line connecting the previous marked point of the real-time handwriting to the marked point is recorded as the tangent direction of the marked point.

4. The real-time handwriting recognition method according to claim 1, characterized in that: Determining the turning point of the real-time handwriting according to the tangent direction of the marking point includes: For each marked point, determine the unit tangent vector of the marked point according to the tangent direction of the marked point; Determine a first angle formed by a unit tangent vector of the marking point and a unit tangent vector of a next marking point of the real-time handwriting; It is determined whether the first angle is greater than a first preset angle, and if so, the marking point is determined as a turning point of the real-time handwriting.

5. The real-time handwriting recognition method according to claim 1, characterized in that: The real-time handwriting display on the electronic display board includes: An infrared network is determined according to the infrared rays from the infrared transmitting end, and a first plane is determined according to the infrared network; Establishing a second plane on the electronic display board that is identical to the first plane; Place the first plane in point-to-point correspondence with the second plane; The specific position of the real-time handwriting on the electronic display board is determined and displayed according to the corresponding relationship between the first plane and the second plane and the specific position of the real-time handwriting on the first plane.

6. The real-time handwriting recognition method according to claim 1, characterized in that: The real-time handwriting is displayed on the electronic display board, and then further includes: Determine the real-time handwriting on the electronic display board before a third preset time at every second preset time; Determine the font of real-time handwriting; For each font, determine whether the font can find the corresponding character C in the character database, and if so, determine all hidden sub-trajectories D in the real-time handwriting formed by the font; For each sub-track D, determine whether there is a part of the connecting line in the sub-track D that corresponds to the pen tip of the stroke of the character C. If so, display the part of the connecting line in the sub-track D that corresponds to the pen tip of the stroke of the character C. If the font cannot find the character C corresponding to the font in the character database, all the hidden sub-trajectories D of the real-time handwriting composed of the font will be displayed.

7. A real-time handwriting recognition device, characterized in that: The real-time handwriting recognition device comprises: The infrared signal monitoring module is used to monitor the infrared receiving end that has not received the infrared signal; A real-time handwriting determination module is used to determine a marking point according to an infrared receiving end that does not receive an infrared signal and then determine a continuous real-time handwriting; A tangent direction determination module is used to determine the tangent direction of the marking point of the real-time handwriting; A turning point determination module is used to determine the turning point of the real-time handwriting according to the tangent direction of the marking point; The first display module is used to determine whether there are two or more turning points, and if so, to determine whether the real-time handwriting is a stroke in the stroke library, and if so, to display the real-time handwriting on the electronic display board; A sub-track determination module is used to divide the real-time handwriting into a plurality of sub-tracks according to the turning points if the real-time handwriting is not a stroke in the stroke library; The real-time handwriting updating module is used to select a sub-track according to the time sequence of the sub-track formation, and determine whether the sub-track is a connected stroke. If so, the sub-track is hidden and the real-time handwriting is hidden and updated; A second display module is used to repeatedly update the real-time handwriting module until all sub-trajectories are judged, and display the real-time handwriting on the electronic display board; A third display module is used to display the real-time handwriting on the electronic display board if there are not two or more turning points; The step of selecting a sub-trajectory according to the time sequence of the sub-trajectories, and judging whether the sub-trajectory is a connected stroke, comprises: Select a sub-trajectory A according to the time sequence of the sub-trajectories; Fit sub-trajectory A to obtain the straight line segment corresponding to sub-trajectory A; Determine the line segment direction of the line segment corresponding to the sub-trajectory A according to the projection point of the marked point on the line segment corresponding to the sub-trajectory A and determine the unit vector of the line segment direction; Determine whether sub-track A has a previous sub-track B in the time sequence of sub-track formation, if so, determine whether the previous sub-track B of sub-track A in the time sequence of sub-track formation is a connected stroke, if so, determine sub-track A as not a connected stroke; If the previous sub-trajectory B of sub-trajectory A in the time sequence of sub-trajectory formation is not a connected stroke, determine a second angle formed by a unit vector of the line segment direction of the straight line segment corresponding to sub-trajectory A and a unit vector of the line segment direction of the straight line segment corresponding to sub-trajectory B; Determine whether the second angle is greater than a second preset angle. If not, determine that the sub-trajectory A is not a connected stroke. If so, determine a third angle formed by a unit vector of the line segment direction of the straight line segment corresponding to the sub-trajectory A and the preset vector. Determine whether the third angle is greater than a third preset angle, if so, determine the sub-trajectory as a connected stroke, if not, determine the sub-trajectory A as not a connected stroke; If sub-track A does not have a previous sub-track B in the time sequence of sub-track formation, sub-track A is determined to be not a connected stroke.

8. A real-time handwriting recognition system, characterized in that: The real-time handwriting recognition system includes: an electronic display board, a handwriting display board and a computer device; The electronic display board is connected to the computer device and is used to display the real-time handwriting of the handwriting display board; The handwriting display board is connected to the computer device and is used for users to write to generate real-time handwriting; The computer device is used to execute the steps of the real-time handwriting recognition method according to any one of claims 1 to 6.

9. The real-time handwriting recognition system according to claim 8, characterized in that: The handwriting display board comprises: a plurality of groups of first infrared modules, a plurality of groups of second infrared modules and a writing day shift; The first infrared module includes an infrared transmitting end and an infrared receiving end, and is arranged in a first direction of the plane of the writing white class; The second infrared module includes an infrared transmitting end and an infrared receiving end, and is arranged in the second direction of the plane of the writing white class; The first infrared module and the second infrared module are used to recognize the real-time handwriting of the user when writing; The writing day shift is used for users to write.

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