A scanning control method, device and medium for a pan / tilt platform

Abstract

The present invention relates to the field of security monitoring, and specifically to a scanning control method, device, and medium for a pan-tilt platform. The present invention first uses a clockwise four-point calibration method to calibrate the scanning area. The four-point method can cover the required monitoring ranges of various shapes, and the area calibrated by this method is convenient for scanning and can also reduce scanning blind spots. Then, based on the summarized three shapes of the monitoring areas, a corresponding scanning method is set for each shape. Not only can the demarcated area be scanned, but it can also be determined whether there are monitoring blind spots in the demarcated area based on the demarcated graphic shape. When running into the blind spot area, special attention will be paid to avoid omissions. The scanning speed is determined based on the field of view angle and the zoom speed, taking into account both the scanning speed and the scanning quality.

Description

Technical Field

[0001] The present invention relates to the field of security monitoring, and in particular to a scanning control method, device and medium of a pan / tilt platform. Background Art

[0002] At present, most security monitoring systems monitor a selected fixed area through a pan-tilt head (PTZ). When switching to the next detection area, manual operation is required, or the designated area is scanned and monitored through a reciprocating scanning method. Among these control methods, the scanning method and control function of the PTZ are relatively simple, single in purpose, less flexible, and the process is cumbersome.

[0003] The pan-tilt scanning of common security equipment can only achieve reciprocating motion at horizontal and pitch angles. Although it can also realize scanning and monitoring of a designated area, the division of the scanning area is relatively simple, and it can only scan a small area. This method is more suitable for scanning areas with a wide monitoring range, but for areas that require key monitoring, its larger scanning range is too redundant, and the scanning area and scanning method cannot be adjusted in time according to actual conditions, which has certain limitations. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the present invention provides a scanning control method, device and medium for a pan-tilt platform, which selects a suitable scanning mode according to a calibrated scanning range, improves scanning efficiency and avoids monitoring blind spots.

[0005] In order to solve the above technical problems, the present invention adopts a technical solution: a scanning control method of a pan / tilt platform, comprising the following steps:

[0006] S01. Calibrate the scanning area. The user defines multiple groups of calibration points. Each group of calibration points has 4 points. The gimbal rotates clockwise from the first point to the second, third, and fourth points, and returns to the origin to obtain a quadrilateral. This quadrilateral is the scanning area. Each group of calibration points obtains a scanning area, and the shape of the scanning area is determined.

[0007] S02. Determine the scanning method. The scanning area determined in step S01 has three shapes: rectangle, trapezoid, and irregular trapezoid. The scanning method for the rectangular scanning area is: use any long side as the base and scan in the other direction. The scanning method for the trapezoidal scanning area is: compare the longest side with the longest parallel side. If the longest side is greater than N times the longest parallel side, scan in the other direction using the longest side as the base. Otherwise, scan in the other direction using the longest parallel side as the base. The scanning method for the irregular trapezoidal scanning area is: compare the lengths of the four sides, find the longest side, and scan in the other direction using the longest side as the base.

[0008] S03. Determine the scanning speed and the pan / tilt rotation speed based on the field of view angle and zoom speed:

[0009] PTZ rotation speed = field of view * (zoom speed + 1) * 0.25;

[0010] S04. Scanning is performed based on the above-determined scanning area, scanning mode, and scanning speed.

[0011] Furthermore, the process of determining the shape of the scanning area is as follows: the scanning area is a quadrilateral, and the quadrilateral is composed of two sets of opposite sides. It is determined whether the slopes of each set of opposite sides are the same. If the slopes of the two sets of opposite sides are the same, the scanning area is a rectangle. If the slopes of one set of opposite sides are the same, and the slopes of the other set of opposite sides are different, the scanning area is a trapezoid. If the slopes of the two sets of opposite sides are different, the scanning area is an irregular quadrilateral.

[0012] Furthermore, when calibrating the scanning area, the legality of the calibration points is determined. When calibrating the second point, the second point is legal if it is in the upper left, upper right, or lower right of the first point. When calibrating the third and fourth points, the third and fourth points are legal if they are in the upper right or lower right of the second point. The rest are illegal points. The scanning area is calibrated according to the legal points. When an illegal point is encountered, an error message is returned.

[0013] Furthermore, if the angle between two sides of the scanning area is less than 45°, it is considered that there is a scanning blind spot between the two sides, and the pan / tilt head moves forward a certain number of steps when passing through the vertices of the two sides.

[0014] Furthermore, after calibrating one scanning area, the calibration of the next scanning area is continued. A maximum of 10 scanning areas can be calibrated. Scanning is performed according to the order in which the scanning areas are calibrated and the corresponding scanning modes are used.

[0015] Furthermore, an automatic switching component is provided, and after scanning one scanning area, the automatic switching component switches to the next scanning area for scanning.

[0016] Furthermore, when determining the scanning mode, there is a manual setting option.

[0017] Furthermore, N∈[2,4].

[0018] The present invention also discloses a scanning control device for a pan-tilt platform, comprising a processor and a memory storing program instructions, wherein the processor is configured to execute the scanning control method for the pan-tilt platform as described above when running the program instructions.

[0019] The present invention further discloses a storage medium storing program instructions, wherein the program instructions, when running, execute the scanning control method of the pan / tilt platform as described above.

[0020] Beneficial effects of the present invention: 1. The present invention can automatically calibrate the scanning area and automatically select a scanning method that is more suitable for the characteristics of the scanning area according to the shape of the defined scanning area, making scanning more flexible and more convenient to use.

[0021] 2. If the scanning speed is too slow, the scanning efficiency will be seriously affected; if the speed is too fast, abnormal conditions in the scanned monitoring area cannot be identified. Therefore, according to the field of view angle, the formula is used to calculate the scanning speed that best suits the current field of view angle.

[0022] 3. The clockwise four-point calibration method is used to define the scanning range. The four-point calibration can cover the required monitoring range of various shapes, and the area calibrated by this method is convenient for scanning and can also reduce the scanning blind area. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a flow chart of the method described in Example 1;

[0024] Figure 2 Schematic diagram of three shapes of scanning area;

[0025] Figure 3 This is a principle block diagram of the state described in Example 2. DETAILED DESCRIPTION

[0026] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0027] Example 1

[0028] This embodiment discloses a scanning control method of a pan / tilt platform, such as Figure 1 As shown, the following steps are included:

[0029] S01. Calibrate the scanning area. The user defines multiple groups of calibration points. Each group of calibration points has 4 points. The gimbal rotates clockwise from the first point to the second, third, and fourth points, and returns to the origin to obtain a quadrilateral. The quadrilateral is the scanning area. Each group of calibration points obtains a scanning area to determine the shape of the scanning area.

[0030] The shape of the scan area is determined by: Figure 2 As shown, the scanning area is a quadrilateral, which consists of two sets of opposite sides. ab and cd are one set of opposite sides, and bc and da are another set of opposite sides. It is determined whether the slopes of each set of opposite sides are the same. If the slopes of the two sets of opposite sides are the same, the scanning area is a rectangle, as shown in Figure 2 As shown in a, if the slopes of one set of opposite sides are the same and the slopes of the other set of opposite sides are different, the scanning area is a trapezoid, as shown in Figure 2 As shown in b, if the slopes of the two sets of opposite sides are different, the scanning area is an irregular trapezoid, as shown in Figure 2 As shown in c.

[0031] When calibrating the scanning area, the legality of the calibration points is determined. When calibrating the second point, the second point is legal if it is in the upper left, upper right, or lower right of the first point. When calibrating the third and fourth points, the third and fourth points are legal if they are in the upper right or lower right of the second point. The rest are illegal points. The scanning area is calibrated according to the legal points. When an illegal point is encountered, an error message is returned.

[0032] S02. Determine the scanning method. The scanning area determined in step S01 has three shapes: rectangle, trapezoid, and irregular trapezoid. The scanning method for a rectangular scanning area is: use any long side as the base and scan in the other direction. The scanning method for a trapezoidal scanning area is: compare the longest side with the longest parallel side. If the longest side is N times longer than the longest parallel side, scan in the other direction using the longest side as the base; otherwise, scan in the other direction using the longest parallel side as the base. The scanning method for an irregular trapezoidal scanning area is: compare the lengths of the four sides, find the longest side, and scan in the other direction using the longest side as the base. During scanning, if the angle between two sides of the scanning area is less than 45°, it is considered that there is a scanning blind spot between the two sides. When the pan / tilt passes the vertex of the two sides, it moves forward a certain number of steps.

[0033] After calibrating one scanning area, continue to calibrate the next scanning area. A maximum of 10 scanning areas can be calibrated. Scanning is performed according to the order in which the scanning areas are calibrated and the corresponding scanning methods are used.

[0034] An automatic switching component automatically switches to the next scanning area after scanning one area. A manual setting option is available for determining the scanning mode. If field staff deem the system's selected scanning mode inappropriate, they can set it manually.

[0035] In this embodiment, N=3. In other embodiments, N may also be other numbers between [2, 4], which is determined according to actual conditions.

[0036] S03. Determine the scanning speed. The speed of the device during the scanning process is not fixed, but is determined by the current camera's field of view. When the image is magnified, if the speed is too fast, the image will be too blurry and the external environment will be difficult to see clearly. When the image is zoomed out, if the speed is too slow, the scanning efficiency will be affected, resulting in a waste of time. Therefore, based on the above two situations, the pan / tilt speed is determined based on the field of view and the zoom speed:

[0037] PTZ rotation speed = field of view * (zoom speed + 1) * 0.25;

[0038] S04. Scanning is performed based on the above-determined scanning area, scanning mode, and scanning speed.

[0039] When defining the scanning range, the present invention calibrates the positions of four points in a clockwise direction. When calibrating the second position, the second point can be located to the upper left, upper right, or lower right of the first point. If it is located to the lower left, it cannot be calibrated in a clockwise direction. If it is determined to be illegal, subsequent points cannot be calibrated. The third and fourth points can only be located to the upper right or lower right of the second point. Only in this way can a quadrilateral be formed in a clockwise direction. The clockwise four-point calibration method is used to define the scanning range. The four-point calibration method can cover the required monitoring range of various shapes. The area calibrated by this method is convenient for scanning and can also reduce scanning blind spots.

[0040] This method has multiple scanning modes. The settings of the scanning modes are mainly based on the shapes of the three monitoring areas summarized, and are designed separately for each shape. It can not only scan the designated area, but also determine whether there are monitoring blind spots in the designated area based on the designated graphic shape. When running into the blind spot area, it will pay special attention to avoid omissions.

[0041] Select the appropriate scanning method through the calibrated range, and make a reasonable choice based on the shape of the scanning area and the scanning method previously planned within the system. If the on-site staff thinks the scanning method selected within the system is unreasonable, they can also set the scanning method themselves.

[0042] It can realize the demarcation and scanning of multiple areas. After completing the calibration of one area, it can continue to calibrate the next area. It supports the calibration of up to 10 scanning areas. The system will scan and monitor each area according to a specific scanning method based on the order of the calibration scanning areas.

[0043] The method described in this embodiment can automatically adapt the scanning method that best suits the current area based on the shape of the calibrated scanning area, thereby avoiding the problems of complex process operations, cumbersome implementation steps, and scanning blind spots that occur during the pan-tilt scanning process. It has the characteristics of simple and convenient operation, quick to use, strong scanning flexibility, and diverse scanning methods.

[0044] Example 2

[0045] The present invention also discloses a scanning control device for a pan / tilt platform, such as Figure 3As shown, the apparatus includes a processor 304 and a memory 301. Optionally, the apparatus may also include a communication interface 302 and a bus 303. The processor 304, communication interface 302, and memory 301 may communicate with each other via bus 303. Communication interface 302 may be used for information transmission. Processor 304 may invoke logic instructions in memory 301 to execute the pan / tilt scanning control method of the aforementioned embodiment.

[0046] In addition, the logic instructions in the memory 301 can be implemented in the form of software functional units and can be stored in a computer-readable storage medium when sold or used as an independent product.

[0047] Memory 301, as a computer-readable storage medium, can be used to store software programs and computer-executable programs, such as the program instructions / modules corresponding to the methods in the embodiments of the present disclosure. Processor 304 executes the program instructions / modules stored in memory 301 to execute functional applications and data processing, thereby implementing the pan / tilt scanning control method in the above-described embodiments.

[0048] The memory 301 may include a program storage area and a data storage area. The program storage area may store an operating system and at least one application required for a function; the data storage area may store data generated based on the use of the terminal device. Furthermore, the memory 301 may include high-speed random access memory and non-volatile memory.

[0049] Example 3

[0050] The present invention further discloses a storage medium storing program instructions, wherein the program instructions, when running, execute the scanning control method of the pan / tilt platform in the above embodiment.

[0051] The aforementioned computer-readable storage medium may be a transient computer-readable storage medium or a non-transitory computer-readable storage medium.

[0052] The technical solutions of the embodiments of the present disclosure may be embodied in the form of a software product, which is stored in a storage medium and includes one or more instructions for causing a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in the embodiments of the present disclosure. The aforementioned storage medium may be a non-transitory storage medium, including: a USB flash drive, a mobile hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, an optical disk, and other media that can store program code, or a transient storage medium.

[0053] The above description and the accompanying drawings sufficiently illustrate the embodiments of the present disclosure to enable those skilled in the art to practice them. Other embodiments may include structural, logical, electrical, process and other changes. The embodiments represent only possible variations. Unless expressly required, individual components and functions are optional, and the order of operations may vary. Parts and features of some embodiments may be included in or replace parts and features of other embodiments. Moreover, the terms used in this application are only used to describe the embodiments and are not used to limit the scope of protection. As used in the description herein, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to also include the plural forms. Similarly, the term "and / or" as used in this application refers to any and all possible combinations of one or more associated listings. In addition, when used in this application, the term "comprise" and its variations "comprises" and / or comprising refer to the presence of stated features, wholes, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or groups thereof. In the absence of further restrictions, an element defined by the sentence "comprising a..." does not exclude the presence of other identical elements in the process, method or device that includes the element. In this article, each embodiment may focus on the differences from other embodiments, and the same and similar parts between the various embodiments can be referenced to each other. For the methods, products, etc. disclosed in the embodiments, if they correspond to the method part disclosed in the embodiments, then the relevant parts can be referred to the description of the method part.

[0054] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software may depend on the specific application and design constraints of the technical solution. The technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the embodiments of the present disclosure. The technicians will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

Claims

1. A scanning control method for a pan / tilt platform, characterized by: The following steps are involved: S01. Calibrate the scanning area. The user defines multiple groups of calibration points. Each group of calibration points has 4 points. The gimbal rotates clockwise from the first point to the second, third, and fourth points, and returns to the origin to obtain a quadrilateral. This quadrilateral is the scanning area. Each group of calibration points obtains a scanning area, and the shape of the scanning area is determined. S02. Determine the scanning method. The scanning area determined in step S01 has three shapes: rectangle, trapezoid, and irregular trapezoid. The scanning method for the rectangular scanning area is: use any long side as the base and scan in the other direction. The scanning method for the trapezoidal scanning area is: compare the longest side with the longest parallel side. If the longest side is greater than N times the longest parallel side, scan in the other direction using the longest side as the base. Otherwise, scan in the other direction using the longest parallel side as the base. The scanning method for the irregular trapezoidal scanning area is: compare the lengths of the four sides, find the longest side, and scan in the other direction using the longest side as the base. S03. Determine the scanning speed and the pan / tilt rotation speed based on the field of view angle and zoom speed: PTZ rotation speed = field of view * (zoom speed + 1) * 0.25; S04. Scanning is performed based on the scanning area, scanning mode, and scanning speed determined above. If the angle between two sides of the scanning area is less than 45°, it is considered that there is a scanning blind spot between the two sides. When the pan / tilt platform passes through the vertex of the two sides, it moves forward a certain number of steps.

2. The scanning control method of a pan / tilt platform according to claim 1, characterized in that: The process of determining the shape of the scanning area is as follows: the scanning area is a quadrilateral, which is composed of two sets of opposite sides. It is determined whether the slopes of each set of opposite sides are the same. If the slopes of the two sets of opposite sides are the same, the scanning area is a rectangle. If the slopes of one set of opposite sides are the same and the slopes of the other set of opposite sides are different, the scanning area is a trapezoid. If the slopes of the two sets of opposite sides are different, the scanning area is an irregular quadrilateral.

3. The scanning control method of a pan / tilt platform according to claim 1, characterized in that: When calibrating the scanning area, the legality of the calibration points is determined. When calibrating the second point, the second point is legal if it is in the upper left, upper right, or lower right of the first point. When calibrating the third and fourth points, the third and fourth points are legal if they are in the upper right or lower right of the second point. The rest are illegal points. The scanning area is calibrated according to the legal points. When an illegal point is encountered, an error message is returned.

4. The scanning control method of a pan / tilt platform according to claim 1, wherein: After calibrating one scanning area, continue to calibrate the next scanning area. A maximum of 10 scanning areas can be calibrated. Scanning is performed according to the order in which the scanning areas are calibrated and the corresponding scanning methods are used.

5. The scanning control method of a pan / tilt platform according to claim 4, characterized in that: An automatic switching component is provided. After scanning one scanning area, the automatic switching component switches to the next scanning area for scanning.

6. The scanning control method of a pan / tilt platform according to claim 1, characterized in that: When determining the scanning method, there is a manual setting option.

7. The scanning control method of a pan / tilt platform according to claim 1, characterized in that: N∈[2,4]。 8. A scanning control device for a pan / tilt platform, comprising a processor and a memory storing program instructions, characterized in that: The processor is configured to execute the scanning control method of the pan / tilt platform according to any one of claims 1 to 7 when running the program instructions.

9. A storage medium storing program instructions, characterized in that: When the program instructions are executed, the scanning control method of the pan / tilt platform according to any one of claims 1 to 7 is executed.

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