Teacher classroom movement track description method, device and equipment and storage medium

Abstract

The invention discloses a teacher classroom movement track description method and device, equipment and a storage medium. Wherein. The method comprises the following steps: acquiring a mapping relation between a holder motor coordinate system of a teacher tracking camera and a classroom coordinate system; acquiring real-time pan-tilt motor coordinates of a teacher tracking camera; according to the mapping relation, converting the real-time cloud deck motor coordinates to obtain real-time classroom coordinates; and drawing points on the classroom coordinate system according to the real-time classroom coordinates, and drawing a classroom movement track of the teacher according to a set of drawn points. The method is combined with AI face tracking, is suitable for classroom teaching scenes, does not need to add extra equipment, is simple in configuration, is accurate and efficient in positioning, is not affected by the environment compared with indoor Bluetooth positioning, and is high in anti-interference capability.

Description

Technical Field

[0001] The present invention relates to the technical field of video image processing, and more specifically, to a method, device, equipment and storage medium for depicting a teacher's classroom motion trajectory. Background Art

[0002] When teachers are teaching, walking around the classroom helps to strengthen classroom management, improve student participation and enhance interaction with students. Therefore, it is often necessary to draw the teacher's classroom movement trajectory for review. Drawing such a trajectory can help analyze the effectiveness of teaching methods, optimize classroom layout, or as part of teacher training to improve teaching skills.

[0003] The existing method of locating teachers drawing trajectory maps in classrooms generally uses Bluetooth positioning technology. The disadvantages of this method are that the layout environment is complicated and requires the assistance of multiple Bluetooth devices, which increases the cost accordingly. Secondly, in complex spatial environments, the stability of the Bluetooth positioning system is slightly poor and is greatly interfered by noise signals. Summary of the invention

[0004] In order to overcome the defects of the existing method of drawing the teacher's movement trajectory that is affected by the environment and has weak anti-interference ability, the present invention provides a method, device, equipment and storage medium for depicting the teacher's classroom movement trajectory. The technical solution adopted by the present invention is as follows.

[0005] In a first aspect, the present invention provides a method for describing a teacher's classroom motion trajectory, comprising:

[0006] Obtain the mapping relationship between the PTZ motor coordinate system of the teacher tracking camera and the classroom coordinate system;

[0007] Get the real-time PTZ motor coordinates of the teacher tracking camera;

[0008] According to the mapping relationship, the real-time PTZ motor coordinates are converted to obtain real-time classroom coordinates;

[0009] Points are plotted on the classroom coordinate system according to the real-time classroom coordinates, and the teacher's classroom movement trajectory is drawn based on the set of plotted points.

[0010] In one embodiment, it further includes: establishing a mapping relationship between the PTZ motor coordinate system and the classroom coordinate system;

[0011] The process of establishing the mapping relationship between the PTZ motor coordinate system and the classroom coordinate system includes:

[0012] Establish the coordinates of the upper left corner, upper right corner, lower right corner and lower left corner of the classroom in the classroom coordinate system;

[0013] The teacher tracking camera takes pictures of the upper left corner, upper right corner, lower right corner and lower left corner of the classroom respectively, and records the coordinates of the pan / tilt motors of the teacher tracking camera at these four corners respectively;

[0014] According to the coordinates of the four corners of the teacher tracking camera and the coordinates of the corresponding four corners in the classroom coordinate system, the mapping relationship between the pan / tilt motor coordinate system and the classroom coordinate system is obtained.

[0015] In one embodiment, the process of obtaining the mapping relationship between the pan / tilt motor coordinate system and the classroom coordinate system according to the coordinates of the four corners of the teacher tracking camera and the coordinates of the corresponding four corners in the classroom coordinate system includes:

[0016] The normalized coordinates corresponding to the classroom coordinate system are (x, y). The coordinates of the upper left corner, upper right corner, lower right corner, and lower left corner in the classroom coordinate system are (0, 0), (k, 0), (k, k), and (0, k), respectively. The normalized coordinate range is 0 to k.

[0017] The coordinates of the gimbal motor are (X, Y). The coordinates of the upper left corner, upper right corner, lower right corner, and lower left corner in the gimbal motor coordinate system are (X1, Y1), (X2, Y2), (X3, Y3), and (X4, Y4) respectively.

[0018] x=k*(X-X0) / w,

[0019] y = k*(Y-Y1) / (Y4-Y1);

[0020] Among them, w=(X2-X1)+(Y-Y1)*[(X3-X4)-(X2-X1)] / (Y4-Y1), X0=(X4-X1)*(Y-Y1) / (Y4-Y1)+X1.

[0021] In one implementation, the value of k ranges from 500 to 1500.

[0022] In one embodiment, it further includes:

[0023] Get the height coordinate H of the podium in the gimbal motor coordinate system;

[0024] Compare the Y and H values ​​in the real-time PTZ motor coordinates to determine whether the teacher is on the podium;

[0025] Or, obtain the height coordinate h of the podium in the classroom coordinate system;

[0026] Compare the sizes of y and h in the real-time classroom coordinates to determine whether the teacher is on the podium.

[0027] In one embodiment, it further includes:

[0028] Record the time point when the teacher passes through the podium height coordinate H in the PTZ motor coordinate system or the podium height coordinate h in the classroom coordinate system;

[0029] Based on the recorded time points and whether the teacher is at the podium, the length of time the teacher is at the podium and the length of time the classroom is under the podium are counted.

[0030] In a second aspect, the present invention provides a device for depicting a teacher's classroom motion trajectory, comprising:

[0031] An acquisition module is used to acquire the mapping relationship between the PTZ motor coordinate system of the teacher tracking camera and the classroom coordinate system; and to acquire the real-time PTZ motor coordinates of the teacher tracking camera;

[0032] A conversion module, used for converting the real-time PTZ motor coordinates according to the mapping relationship to obtain real-time classroom coordinates;

[0033] The generation module is used to draw points on the classroom coordinate system according to the real-time classroom coordinates, and to draw the teacher's classroom movement trajectory according to the set of drawn points.

[0034] In one embodiment, it further includes:

[0035] Establish a module for establishing the mapping relationship between the PTZ motor coordinate system and the classroom coordinate system;

[0036] The process of establishing the mapping relationship between the PTZ motor coordinate system and the classroom coordinate system by the establishment module includes:

[0037] Establish the coordinates of the upper left corner, upper right corner, lower right corner and lower left corner of the classroom in the classroom coordinate system;

[0038] The teacher tracking camera takes pictures of the upper left corner, upper right corner, lower right corner and lower left corner of the classroom respectively, and records the coordinates of the pan / tilt motors of the teacher tracking camera at these four corners respectively;

[0039] According to the coordinates of the four corners of the teacher tracking camera and the coordinates of the corresponding four corners in the classroom coordinate system, the mapping relationship between the pan / tilt motor coordinate system and the classroom coordinate system is obtained.

[0040] In a third aspect, the present invention provides a computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements any of the above-mentioned methods when executing the program.

[0041] In a fourth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the program, when executed by a processor, implements the method of any of the above-mentioned embodiments.

[0042] In the present invention, the coordinate parameters of the teacher tracking camera when shooting the teacher can reflect the teacher's position in the classroom to a certain extent. As long as these coordinate parameters are converted to the classroom coordinate system, the teacher's position in the classroom coordinate system can be approximated. The real-time pan / tilt motor coordinates of the teacher tracking camera are converted to the classroom coordinate system to obtain the teacher's classroom motion trajectory. Different from the previous Bluetooth positioning technology, the present invention combines AI face tracking, is suitable for classroom teaching scenes, does not require additional equipment, has simple configuration, accurate and efficient positioning, and is not affected by the environment and has strong anti-interference ability compared to indoor Bluetooth positioning. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a schematic diagram of the overall flow of an implementation method of Example 1 of the present invention.

[0044] Figure 2 It is a schematic diagram of the classroom area photographed in the first embodiment of the present invention.

[0045] Figure 3 It is a schematic diagram of the overall structure of an implementation method of Example 21 of the present invention. DETAILED DESCRIPTION

[0046] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0047] It should be noted that the terms "first\second\..." involved in the embodiments of the present invention are only used to distinguish similar objects, and do not represent a specific order for the objects. It is understandable that the specific order or sequence of "first\second\..." can be interchanged where permitted. It should be understood that the objects distinguished by "first\second\..." can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein.

[0048] Embodiment 1

[0049] See also Figure 1 , Figure 1 1 is a flow chart of a method for describing a teacher's classroom motion trajectory provided in Embodiment 1 of the present invention, the method comprising step S110, step S120, step S130 and step S140. It should be noted that step S110, step S120, step S130 and step S140 are merely reference numerals for the purpose of clearly explaining the embodiment and the appendix. Figure 1The corresponding relationship does not limit the order of the steps in this embodiment.

[0050] Step S110, obtaining a mapping relationship between the pan / tilt motor coordinate system of the teacher tracking camera and the classroom coordinate system;

[0051] Step S120, obtaining the real-time PTZ motor coordinates of the teacher tracking camera;

[0052] Step S130, converting the real-time PTZ motor coordinates according to the mapping relationship to obtain real-time classroom coordinates;

[0053] Step S140, plotting points on the classroom coordinate system according to the real-time classroom coordinates, and drawing the teacher's classroom movement trajectory according to the set of plotted points.

[0054] This method is suitable for a recording and broadcasting host, which receives multiple video data, such as the video from the teacher's panoramic camera, the video from the teacher's tracking camera, the video from the student's panoramic camera, the video from the student's tracking camera, etc. In addition, it can also receive computer output video, video about teaching blackboards, etc. In addition to receiving video data, the recording and broadcasting host also receives audio data, such as the audio from the teacher's microphone, the audio from the student microphone / student microphone group, etc.

[0055] The teacher tracking camera is a smart camera designed for educational environments. It can automatically track and focus on the teacher, ensuring that the teacher always stays in the center of the video screen during the lecture. The teacher camera uses image recognition technology to automatically identify and track the teacher's position. Even if the teacher moves in the classroom, the camera can adjust the angle and focus in real time to keep the teacher in the best position in the picture.

[0056] The coordinate system of the teacher tracking camera usually refers to the positioning and rotation system of the camera in three-dimensional space, while the classroom coordinate system refers to the physical space coordinate system in the classroom. The conversion between the coordinates of the teacher tracking camera and the classroom coordinates can usually be achieved by establishing a mapping relationship of a mathematical model to convert the points in the camera coordinate system to the classroom coordinate system.

[0057] Generally speaking, the conversion between the pan / tilt motor coordinate system of the teacher tracking camera and the classroom coordinate system can be achieved through the following steps: determine the relative position and rotation angle between the camera coordinate system and the classroom coordinate system; select an appropriate coordinate conversion model, such as the Bursa seven-parameter conversion method; obtain the parameters required for the conversion, such as translation, rotation, and scale change parameters, through on-site calibration; use the mathematical model formula of coordinate conversion to convert the points in the camera coordinate system to the classroom coordinate system; implement coordinate conversion to ensure that the converted coordinates meet the accuracy requirements, and make necessary adjustments.

[0058] In summary, after the converted mapping relationship is obtained, step S110 acquires the mapping relationship.

[0059] As mentioned above, the teacher tracking camera can automatically track and focus on the teacher, ensuring that the teacher always stays in the center of the video screen when giving a lecture. Therefore, the coordinate parameters of the teacher tracking camera when shooting the teacher can reflect the teacher's position in the classroom to a certain extent. As long as these coordinate parameters are converted to the classroom coordinate system, the teacher's position in the classroom coordinate system can be approximately obtained. Therefore, in this method, step S120 obtains the real-time pan / tilt motor coordinates of the teacher tracking camera, and step S130 converts the real-time pan / tilt motor coordinates obtained in step S120 according to the obtained mapping relationship to obtain the real-time classroom coordinates. Step S140 points each real-time classroom coordinate in the classroom coordinate system to obtain a collection of these plotted points. The collection of these plotted points is the position where the teacher has stopped. By stringing these points together according to the actual relationship, the teacher's classroom movement trajectory can be drawn.

[0060] In this method, the coordinate parameters of the teacher tracking camera when shooting the teacher can reflect the teacher's position in the classroom to a certain extent. As long as these coordinate parameters are converted to the classroom coordinate system, the teacher's position in the classroom coordinate system can be approximated. The real-time pan / tilt motor coordinates of the teacher tracking camera are converted to the classroom coordinate system to obtain the teacher's classroom movement trajectory. Different from previous Bluetooth positioning technologies, this method combines AI face tracking and is suitable for classroom teaching scenarios. It does not require additional equipment, has simple configuration, accurate and efficient positioning, and is not affected by the environment and has strong anti-interference ability compared to indoor Bluetooth positioning.

[0061] In one embodiment, the method for depicting teacher's classroom movement trajectory also includes: step S100.

[0062] Step S100, establishing a mapping relationship between the PTZ motor coordinate system and the classroom coordinate system;

[0063] The process of establishing the mapping relationship between the pan / tilt motor coordinate system and the classroom coordinate system includes: step S101, step S102 and step S103.

[0064] Step S101, establishing the coordinates of the upper left corner, upper right corner, lower right corner and lower left corner of the classroom in the classroom coordinate system;

[0065] Step S102, the teacher tracking camera respectively shoots the upper left corner, upper right corner, lower right corner and lower left corner of the classroom, and respectively records the pan / tilt motor coordinates of the teacher tracking camera at these four corners;

[0066] Step S103, obtaining a mapping relationship between the pan / tilt motor coordinate system and the classroom coordinate system according to the coordinates of the four corners of the teacher tracking camera and the coordinates of the corresponding four corners in the classroom coordinate system.

[0067] Usually the classroom is a rectangle. In step S101, the coordinates of the upper left corner, upper right corner, lower right corner and lower left corner of the classroom in the classroom coordinate system are established, such as (0,0), (1000,0), (1000,1000), (0,1000). Then, in step S102, the teacher tracking camera respectively shoots the upper left corner, upper right corner, lower right corner and lower left corner of the classroom, and records the PTZ motor coordinates of the teacher tracking camera at these four corners, such as (X1,Y1), (X2,Y2), (X3,Y3), (X4,Y4). In step S103, the area enclosed by the four corners is mapped and matched, so as to obtain the mapping relationship between the PTZ motor coordinate system and the classroom coordinate system.

[0068] In one implementation, the process of step S103 includes:

[0069] The normalized coordinates corresponding to the classroom coordinate system are (x, y). The coordinates of the upper left corner, upper right corner, lower right corner, and lower left corner in the classroom coordinate system are (0, 0), (k, 0), (k, k), and (0, k), respectively. The normalized coordinate range is 0 to k.

[0070] The coordinates of the gimbal motor are (X, Y). The coordinates of the upper left corner, upper right corner, lower right corner, and lower left corner in the gimbal motor coordinate system are (X1, Y1), (X2, Y2), (X3, Y3), and (X4, Y4) respectively.

[0071] x=k*(X-X0) / w,

[0072] y = k*(Y-Y1) / (Y4-Y1);

[0073] Among them, w=(X2-X1)+(Y-Y1)*[(X3-X4)-(X2-X1)] / (Y4-Y1), X0=(X4-X1)*(Y-Y1) / (Y4-Y1)+X1.

[0074] like Figure 2 As shown, Figure 2 This is a schematic diagram of the classroom area. Figure 2 It can be seen that although the classroom area is rectangular, the photographed classroom area is trapezoidal, so step S103 is actually a process of converting the trapezoidal area coordinates into rectangular area coordinates.

[0075] like Figure 2As shown, the coordinates of the four corners of the gimbal motor coordinate system are (X1, Y1), (X2, Y2), (X3, Y3), and (X4, Y4). The obtained gimbal motor coordinates are (X, Y). Then the distance from the left and right boundaries at the height Y is w, and at the height Y, the corresponding left boundary coordinate is X0.

[0076] Wherein, w = (X2-X1) + (Y-Y1) * [(X3-X4) - (X2-X1)] / (Y4-Y1);

[0077] X0=(X4-X1)*(Y-Y1) / (Y4-Y1)+X1.

[0078] At this time, the coordinates of the four corners of the classroom coordinate system are (0,0), (k,0), (k,k), (0,k), and the corresponding normalized coordinates of the classroom coordinate system are (x,y), x=k*(X-X0) / w, y=k*(Y-Y1) / (Y4-Y1).

[0079] Preferably, the value of k ranges from 500 to 1500.

[0080] Taking k as 1000 as an example, x=1000*(X-X0) / w, y=1000*(Y-Y1) / (Y4-Y1).

[0081] In one embodiment, the method for describing the teacher's classroom movement trajectory further includes:

[0082] Get the height coordinate H of the podium in the gimbal motor coordinate system;

[0083] Compare the Y and H values ​​in the real-time PTZ motor coordinates to determine whether the teacher is on the podium;

[0084] Or, obtain the height coordinate h of the podium in the classroom coordinate system;

[0085] Compare the sizes of y and h in the real-time classroom coordinates to determine whether the teacher is on the podium.

[0086] In the classroom, the podium is a fixed area, and the image captured by the teacher tracking camera is an area at a certain height. Therefore, we can judge whether the teacher is on the podium by comparing the size of Y and H in the real-time pan-tilt motor coordinates. For example, when the Y coordinate is greater than H, it is judged that the teacher is under the podium; when the Y coordinate is less than H, it is judged that the teacher is on the podium.

[0087] Similarly, the podium height coordinate H in the pan-tilt motor coordinate system can be converted into the podium height coordinate h=k*(H-Y1) / (Y3-YI) in the classroom coordinate system. Then, by comparing the sizes of y and h in the real-time classroom coordinates, it can be determined whether the teacher is on the podium.

[0088] In one embodiment, the method for describing the teacher's classroom movement trajectory further includes:

[0089] Record the time point when the teacher passes through the podium height coordinate H in the PTZ motor coordinate system or the podium height coordinate h in the classroom coordinate system;

[0090] Based on the recorded time points and whether the teacher is at the podium, the length of time the teacher is at the podium and the length of time the classroom is under the podium are counted.

[0091] When the teacher's trajectory passes through the podium height coordinate H in the pan-tilt motor coordinate system or the podium height coordinate h in the classroom coordinate system, the time point at this time is recorded, and the time under the podium is counted as the teacher's inspection time, and the time on the podium is counted as the teacher's teaching time, which is used to reflect whether the teacher's teaching method in this class is mainly student discussion or classroom teaching.

[0092] Embodiment 2

[0093] Corresponding to the method of embodiment 1, as Figure 3 As shown, the present invention also provides a device 3 for depicting a teacher's classroom motion trajectory, including: an acquisition module 310, a conversion module 320, and a generation module 330.

[0094] The acquisition module 310 is used to acquire the mapping relationship between the PTZ motor coordinate system of the teacher tracking camera and the classroom coordinate system; and acquire the real-time PTZ motor coordinates of the teacher tracking camera;

[0095] A conversion module 320, configured to convert the real-time PTZ motor coordinates according to the mapping relationship to obtain real-time classroom coordinates;

[0096] The generation module 330 is used to draw points on the classroom coordinate system according to the real-time classroom coordinates, and draw the teacher's classroom movement trajectory according to the set of drawn points.

[0097] In one embodiment, the teacher classroom motion trajectory depicting device further includes:

[0098] Establish a module for establishing the mapping relationship between the PTZ motor coordinate system and the classroom coordinate system;

[0099] The process of establishing the mapping relationship between the PTZ motor coordinate system and the classroom coordinate system by the establishment module includes:

[0100] Establish the coordinates of the upper left corner, upper right corner, lower right corner and lower left corner of the classroom in the classroom coordinate system;

[0101] The teacher tracking camera takes pictures of the upper left corner, upper right corner, lower right corner and lower left corner of the classroom respectively, and records the coordinates of the pan / tilt motors of the teacher tracking camera at these four corners respectively;

[0102] According to the coordinates of the four corners of the teacher tracking camera and the coordinates of the corresponding four corners in the classroom coordinate system, the mapping relationship between the pan / tilt motor coordinate system and the classroom coordinate system is obtained.

[0103] In one embodiment, the process of obtaining the mapping relationship between the pan / tilt motor coordinate system and the classroom coordinate system according to the coordinates of the four corners of the teacher tracking camera and the coordinates of the corresponding four corners in the classroom coordinate system includes:

[0104] The normalized coordinates corresponding to the classroom coordinate system are (x, y). The coordinates of the upper left corner, upper right corner, lower right corner, and lower left corner in the classroom coordinate system are (0, 0), (k, 0), (k, k), and (0, k), respectively. The normalized coordinate range is 0 to k.

[0105] The coordinates of the gimbal motor are (X, Y). The coordinates of the upper left corner, upper right corner, lower right corner, and lower left corner in the gimbal motor coordinate system are (X1, Y1), (X2, Y2), (X3, Y3), and (X4, Y4) respectively.

[0106] x=k*(X-X0) / w,

[0107] y = k*(Y-Y1) / (Y4-Y1);

[0108] Among them, w=(X2-X1)+(Y-Y1)*[(X3-X4)-(X2-X1)] / (Y4-Y1), X0=(X4-X1)*(Y-Y1) / (Y4-Y1)+X1.

[0109] In one implementation, the value of k ranges from 500 to 1500.

[0110] In one embodiment, the teacher classroom motion trajectory depicting device further includes:

[0111] The podium judgment module is used to obtain the podium height coordinate H in the pan-tilt motor coordinate system, compare the size of Y and H in the real-time pan-tilt motor coordinates, and judge whether the teacher is on the podium; or, obtain the podium height coordinate h in the classroom coordinate system, compare the size of y and h in the real-time classroom coordinates, and judge whether the teacher is on the podium.

[0112] In one embodiment, the podium judgment module is also used to record the time point when the teacher passes through the podium height coordinate H in the pan-tilt motor coordinate system or the podium height coordinate h in the classroom coordinate system; based on the recorded time point and whether the teacher is on the podium, the length of time the teacher is on the podium and the length of time the classroom is under the podium are counted.

[0113] In this device, the coordinate parameters of the teacher tracking camera when shooting the teacher can reflect the teacher's position in the classroom to a certain extent. As long as these coordinate parameters are converted to the classroom coordinate system, the teacher's position in the classroom coordinate system can be approximated. The real-time pan / tilt motor coordinates of the teacher tracking camera are converted to the classroom coordinate system to obtain the teacher's classroom movement trajectory. Unlike previous Bluetooth positioning technologies, this device combines AI face tracking and is suitable for classroom teaching scenarios. It does not require additional equipment, has simple configuration, accurate and efficient positioning, and is not affected by the environment and has strong anti-interference capabilities compared to indoor Bluetooth positioning.

[0114] Embodiment 3

[0115] An embodiment of the present invention further provides a storage medium on which computer instructions are stored. When the instructions are executed by a processor, the method for depicting the teacher's classroom motion trajectory of any of the above embodiments is implemented.

[0116] Those skilled in the art can understand that: all or part of the steps of implementing the above method embodiments can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above method embodiments; and the aforementioned storage medium includes: mobile storage devices, random access memories (RAM), read-only memories (ROM), magnetic disks or optical disks, etc., various media that can store program codes.

[0117] Alternatively, if the above-mentioned integrated unit of the present invention is implemented in the form of a software function module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of the present invention can be essentially or partly reflected in the form of a software product that contributes to the relevant technology. The computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, terminal, or network device, etc.) to execute all or part of the methods of each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as mobile storage devices, RAM, ROM, magnetic disks or optical disks.

[0118] Corresponding to the above-mentioned computer storage medium, in one embodiment, a computer device is also provided, which includes a memory, an encoder, and a computer program stored in the memory and executable on the encoder, wherein when the encoder executes the program, it implements any one of the methods for depicting the teacher's classroom motion trajectory in the above-mentioned embodiments.

[0119] The above-mentioned computer equipment can reflect the teacher's position in the classroom to a certain extent based on the coordinate parameters of the teacher tracking camera when shooting the teacher. As long as these coordinate parameters are converted to the classroom coordinate system, the teacher's position in the classroom coordinate system can be approximated. The real-time pan / tilt motor coordinates of the teacher tracking camera are converted to the classroom coordinate system to obtain the teacher's classroom movement trajectory. Different from previous Bluetooth positioning technologies, the above-mentioned computer equipment is combined with AI face tracking, which is suitable for classroom teaching scenarios. It does not require additional equipment, has simple configuration, accurate and efficient positioning, and is not affected by the environment and has strong anti-interference ability compared to indoor Bluetooth positioning.

[0120] 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.

[0121] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A method for describing the movement trajectory of a teacher in a classroom, characterized in that: include: Obtain the mapping relationship between the PTZ motor coordinate system of the teacher tracking camera and the classroom coordinate system; Get the real-time PTZ motor coordinates of the teacher tracking camera; According to the mapping relationship, the real-time PTZ motor coordinates are converted to obtain real-time classroom coordinates; Points are plotted on the classroom coordinate system according to the real-time classroom coordinates, and the teacher's classroom movement trajectory is drawn based on the set of plotted points.

2. The method for describing the teacher's classroom movement trajectory according to claim 1, characterized in that: Also includes: Establish the mapping relationship between the PTZ motor coordinate system and the classroom coordinate system; The process of establishing the mapping relationship between the PTZ motor coordinate system and the classroom coordinate system includes: Establish the coordinates of the upper left corner, upper right corner, lower right corner and lower left corner of the classroom in the classroom coordinate system; The teacher tracking camera takes pictures of the upper left corner, upper right corner, lower right corner and lower left corner of the classroom respectively, and records the coordinates of the pan / tilt motors of the teacher tracking camera at these four corners respectively; According to the coordinates of the four corners of the teacher tracking camera and the coordinates of the corresponding four corners in the classroom coordinate system, the mapping relationship between the pan / tilt motor coordinate system and the classroom coordinate system is obtained.

3. The method for describing the teacher's classroom movement trajectory according to claim 2, characterized in that: The process of obtaining the mapping relationship between the pan / tilt motor coordinate system and the classroom coordinate system according to the coordinates of the four corners of the teacher tracking camera and the coordinates of the corresponding four corners in the classroom coordinate system includes: The normalized coordinates corresponding to the classroom coordinate system are (x, y). The coordinates of the upper left corner, upper right corner, lower right corner, and lower left corner in the classroom coordinate system are (0, 0), (k, 0), (k, k), and (0, k), respectively. The normalized coordinate range is 0 to k. The coordinates of the gimbal motor are (X, Y). The coordinates of the upper left corner, upper right corner, lower right corner, and lower left corner in the gimbal motor coordinate system are (X1, Y1), (X2, Y2), (X3, Y3), and (X4, Y4) respectively. x=k*(X-X0) / w, y = k*(Y-Y1) / (Y4-Y1); Among them, w=(X2-X1)+(Y-Y1)*[(X3-X4)-(X2-X1)] / (Y4-Y1), X0=(X4-X1)*(Y-Y1) / (Y4-Y1)+X1.

4. The method for describing the teacher's classroom movement trajectory according to claim 3 is characterized in that: The value range of k is 500 to 1500.

5. The method for describing the teacher's classroom movement trajectory according to any one of claims 1 to 4, characterized in that: Also includes: Get the height coordinate H of the podium in the gimbal motor coordinate system; Compare the Y and H values ​​of the real-time PTZ motor coordinates to determine whether the teacher is on the podium; Or, obtain the height coordinate h of the podium in the classroom coordinate system; Compare the sizes of y and h in the real-time classroom coordinates to determine whether the teacher is on the podium.

6. The method for describing the teacher's classroom movement trajectory according to claim 5, characterized in that: Also includes: Record the time point when the teacher passes through the podium height coordinate H in the PTZ motor coordinate system or the podium height coordinate h in the classroom coordinate system; Based on the recorded time points and whether the teacher is at the podium, the length of time the teacher is at the podium and the length of time the classroom is under the podium are counted.

7. A device for depicting the movement trajectory of a teacher in a classroom, characterized in that: include: An acquisition module is used to obtain the mapping relationship between the PTZ motor coordinate system of the teacher tracking camera and the classroom coordinate system; Get the real-time PTZ motor coordinates of the teacher tracking camera; A conversion module, used for converting the real-time PTZ motor coordinates according to the mapping relationship to obtain real-time classroom coordinates; The generation module is used to draw points on the classroom coordinate system according to the real-time classroom coordinates, and to draw the teacher's classroom movement trajectory according to the set of drawn points.

8. The device for depicting teacher's classroom movement trajectory according to claim 7, characterized in that: Also includes: Establish a module for establishing the mapping relationship between the PTZ motor coordinate system and the classroom coordinate system; The process of establishing the mapping relationship between the PTZ motor coordinate system and the classroom coordinate system by the establishment module includes: Establish the coordinates of the upper left corner, upper right corner, lower right corner and lower left corner of the classroom in the classroom coordinate system; The teacher tracking camera takes pictures of the upper left corner, upper right corner, lower right corner and lower left corner of the classroom respectively, and records the coordinates of the pan / tilt motors of the teacher tracking camera at these four corners respectively; According to the coordinates of the four corners of the teacher tracking camera and the coordinates of the corresponding four corners in the classroom coordinate system, the mapping relationship between the pan / tilt motor coordinate system and the classroom coordinate system is obtained.

9. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the method according to any one of claims 1 to 6 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 6 is implemented.

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