Camera calibration support, method, device and system

Abstract

The invention provides a camera calibration support, method, device and system, and relates to the field of artificial intelligence, in particular to the field of computer vision. The specific implementation scheme is as follows: a connecting rod; the light source is arranged on the connecting rod; the multi-direction connecting piece is connected with a plurality of connecting rods extending in different directions; the controller is used for controlling the flicker frequency of the light source; the supporting structure is connected with the multi-direction connecting piece and used for supporting the multiple connecting rods. According to the embodiment, clear and stable three-dimensional reference points can be provided, and the three-dimensional calibration precision of the camera is remarkably improved. The depth-of-field ratio can be accurately obtained, different scene requirements can be met, and a foundation is laid for wide application of the camera.

Description

Technical Field

[0001] The present disclosure relates to the field of artificial intelligence, and in particular to the field of computer vision, and specifically to a camera calibration bracket, method, device and system. Background Art

[0002] Cameras are becoming increasingly important in the field of computer vision, especially in capturing high-speed dynamic scenes. However, existing camera calibration methods have limitations, especially in the lack of accuracy in monocular depth estimation for stereo vision. Traditional methods mainly rely on scintillation calibration plates, which can achieve basic calibration but have difficulty in accurately obtaining depth of field information, resulting in poor performance in 3D reconstruction and depth perception tasks. Summary of the invention

[0003] The present disclosure provides a camera calibration bracket, method, apparatus, system, device, storage medium and computer program product.

[0004] According to a first aspect of the present disclosure, a camera calibration bracket is provided, comprising: a connecting rod; a light source, arranged on the connecting rod; a multi-directional connecting piece, connected to a plurality of connecting rods extending in different directions; a controller, for controlling the flashing frequency of the light source; and a supporting structure, connected to the multi-directional connecting piece, for supporting the plurality of connecting rods.

[0005] According to a second aspect of the present disclosure, a camera calibration method is provided, comprising: sending an instruction to control the flashing frequency of a light source at a corresponding point in the bracket to a controller in the bracket according to the first aspect according to the points required for calculating camera extrinsic parameters; controlling a camera to capture an image of the light source; and calculating the camera extrinsic parameters according to an actual spacing between the light sources and the image.

[0006] According to a third aspect of the present disclosure, a camera calibration system is provided, comprising: a camera to be calibrated; the bracket according to the first aspect; and a processor for executing the method described in the second aspect.

[0007] According to a fourth aspect of the present disclosure, a camera calibration device is provided, comprising: a light source control unit, configured to send an instruction to a controller in the bracket of the first aspect to control the lighting of the light source at the corresponding point in the bracket according to the point required for calculating the camera extrinsic parameter; an image acquisition unit, configured to control the camera to acquire an image of the light source; and an extrinsic parameter calculation unit, configured to calculate the camera extrinsic parameter according to the actual spacing between the light sources and the image.

[0008] According to the fifth aspect of the present disclosure, an electronic device is provided, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the method described in the second aspect.

[0009] According to a sixth aspect of the present disclosure, a non-transitory computer-readable storage medium storing computer instructions is provided, wherein the computer instructions are used to cause the computer to execute the method described in the second aspect.

[0010] According to a seventh aspect of the present disclosure, a computer program product is provided, comprising a computer program, wherein the computer program implements the method described in the second aspect when executed by a processor.

[0011] The camera calibration bracket, method, device and system provided by the embodiments of the present disclosure construct a three-dimensional structure through connecting rods and multi-directional connectors, breaking through the limitations of traditional planar calibration plates and providing a true three-dimensional calibration point distribution. Multiple connecting rods can be connected together to meet various calibration requirements from small laboratories to large outdoor scenes. By using light sources in different positions, accurate depth and scale information is provided to the camera, significantly improving the accuracy of monocular depth estimation. The connecting rods can be assembled into various three-dimensional structures to achieve coverage of the full field of view of the camera, solving the problem of limited viewing angle of the planar calibration plate, overcoming the limitation of the screen size of the traditional method in large scenes, and realizing long-distance precise calibration through high-brightness light sources. By adjusting the flashing frequency of the light source through the controller, it is possible to maintain good imaging effects under various lighting conditions, reduce ambient light interference, and simulate complex dynamic three-dimensional environments to improve the calibration accuracy in practical applications.

[0012] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present disclosure, nor is it intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The accompanying drawings are used to better understand the present solution and do not constitute a limitation of the present disclosure.

[0014] Figure 1 is an architectural diagram of a camera calibration system according to the present disclosure;

[0015] Figure 2a , 2b is a schematic diagram of the structure of a camera calibration bracket according to the present disclosure;

[0016] Figure 3 is a flow chart of an embodiment of a camera calibration method according to the present disclosure;

[0017] Figure 4 is a structural schematic diagram of an embodiment of a camera calibration device according to the present disclosure;

[0018] Figure 5 It is a schematic diagram of the structure of a computer system of an electronic device suitable for implementing an embodiment of the present disclosure. DETAILED DESCRIPTION

[0019] The following is a description of exemplary embodiments of the present disclosure in conjunction with the accompanying drawings, including various details of the embodiments of the present disclosure to facilitate understanding, which should be considered as merely exemplary. Therefore, it should be recognized by those of ordinary skill in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the present disclosure. Similarly, for the sake of clarity and conciseness, descriptions of well-known functions and structures are omitted in the following description.

[0020] Figure 1 An exemplary system architecture is shown to which an embodiment of a camera calibration method or a camera calibration device of the present disclosure can be applied.

[0021] like Figure 1 As shown, the system architecture may include a camera to be calibrated 110 , a camera calibration bracket 100 , and a processor 120 .

[0022] The camera 110 to be calibrated may be a common camera, a depth camera, or an event camera.

[0023] The processor 120 is used to execute the camera calibration method shown in the process 300 .

[0024] The camera calibration bracket 100 may include a connecting rod 101 , a light source 102 , a multi-directional connecting member 103 , a controller 104 and a supporting structure 105 .

[0025] The multi-directional connecting member 103 is connected to a plurality of connecting rods 101 extending in different directions. Figure 1 Only the connecting rods 101 extending in four directions are schematically drawn. The camera calibration bracket 100 may include multiple connecting rods 101 of fixed length. Any two fixed connecting rods 101 can be spliced ​​together to form a longer connecting rod, and multiple connecting rods 101 can be spliced ​​together to form a long rod with N times the fixed length, which can be arbitrarily combined into various three-dimensional structures. Figure 1 Each direction is formed by splicing two connecting rods 101, which is only used as an example, and more connecting rods can actually be spliced.

[0026] The light source 102 can be fixedly mounted on the connecting rod 101, or can be detachably mounted on the connecting rod 101. The light source 102 can be an LED lamp, or can be other luminous light sources. The light source 102 can be an active light source that needs to be connected to a wire, or can be a passive light source that does not need to be connected to a wire but is powered by a battery. Each connecting rod 101 has the same number of light sources 102. After the connecting rods 102 are spliced ​​into a long rod, the distance between the light sources 102 is fixed. The camera extrinsic parameters can only be calculated if the distance is known.

[0027] The controller 104 can control the flickering frequency of the light source 102. If an active light source is used, the flickering frequency of the light source 102 can be controlled by controlling the switching frequency of the power supply. If a passive light source is used, a communication connection can be directly established with the light source 102 to directly control the flickering frequency of the light source 102. The flickering frequency refers to the time interval between the light source emitting light, and can also be set to always on, that is, the flickering frequency is 0. The controller 104 can also set the delayed light-emitting time, which refers to the time for delaying the execution of the instruction after sending the instruction to light up the light source. The default value is 0, that is, there is no delay in light emission. The flickering frequency + delayed light-emitting time constitutes the flickering mode. A fixed flickering mode can be preset in the controller 104, and the user can directly select the flickering mode through the controller 104. The controller 104 also supports the user to manually set the flickering frequency and delayed light-emitting time.

[0028] All light sources can be set to the same flashing frequency, or different flashing frequencies can be set for each light source, or the flashing frequencies can be set in groups. The same flashing frequency can also be set, but the delayed light emission time is staggered. For example, Figure 1 The light sources on the connecting rods extending in the same direction can be divided into a group, all of which are set to the same flashing frequency of 2 times per second, but with different delay lighting times. The light source on the upper left connecting rod starts to light up at time t, then the light source on the upper right connecting rod starts to light up at time t+100 milliseconds, the light source on the lower right connecting rod starts to light up at time t+200 milliseconds, and the light source on the lower right connecting rod starts to light up at time t+300 milliseconds.

[0029] The support structure 105 is connected to the multi-directional connecting member 103 and is used to support the plurality of connecting rods 101. The support structure 105 may be a tripod or other structure.

[0030] It should be noted that the camera calibration method provided in the embodiments of the present disclosure is generally executed by the processor 120 , and accordingly, the camera calibration device is generally disposed in the processor 120 .

[0031] It should be understood that Figure 1 The number of cameras to be calibrated, camera calibration brackets, and processors in the embodiment is only for illustration. Any number of cameras to be calibrated, camera calibration brackets, and processors may be provided according to implementation requirements.

[0032] In some optional implementations of this embodiment, the multi-directional connector 103 may include a second connector 1032, the second connector 1032 includes a cross-shaped body, the cross-shaped body has a first end A and a second end B opposite to each other in the first direction, and a third end C and a fourth end D opposite to each other in the second direction; wherein the first end A, the second end B and the third end C are respectively connected to different connecting rods, the fourth end is connected to the supporting structure, and the first direction (the straight line where AB is located) and the second direction (the straight line where CD is located) are perpendicular to each other. The second connector 1032 can be used alone to connect three connecting rods. Forming a structure such as Figure 2b The "up, left, and right" long structure shown: by connecting multiple rods, a structure covering a larger space range is formed.

[0033] In some optional implementations of this embodiment, the multi-directional connector 103 includes a first connector 1031; the first connector 1031 includes a bottom plate E and a plurality of protrusions F disposed on one side of the bottom plate, and the ends of the plurality of protrusions F away from the bottom plate are respectively connected to different connecting rods. The connecting rods can be freely combined to realize various spatial structures, such as Figure 2a The "spatial cross" shown: a cross-shaped structure is formed in three-dimensional space, providing all-round calibration points.

[0034] In some optional implementations of this embodiment, the multi-directional connector 103 includes a second connector 1032, at least one first connector 1031 and a fastener; the second connector 1032 includes a cross-shaped body, the cross-shaped body has a first end A and a second end B relative to each other in the first direction, and a third end C and a fourth end D relative to each other in the second direction; wherein the first end A, the second end B and the third end C are respectively connected to different connecting rods, the fourth end is connected to the supporting structure, and the first direction (the straight line where AB is located) and the second direction (the straight line where CD is located) are perpendicular to each other. The first connector 1031 includes a bottom plate E and a plurality of protrusions F arranged on one side of the bottom plate, and the ends of the plurality of protrusions F away from the bottom plate are respectively connected to different connecting rods.

[0035] The second connecting member 1032 is disposed on a side of the at least one first connecting member 1031 away from the protrusion F, and is connected to the at least one first connecting member 1031 via a fastener. Figure 1 In the figure, two first connecting members 1031 are used, but only one first connecting member 1031 may be used. Figure 1 Not shown in the figure, it can be a bolt or a buckle, etc., which is used to fix the second connecting member 1032 and the first and second connecting members 1032 together.

[0036] In some optional implementations of this embodiment, the first end A, the second end B and the third end C are detachably connected to the connecting rod, and the fourth end D is detachably connected to the supporting structure. The detachable connection may be a snap-fit, threaded connection or the like.

[0037] In some optional implementations of this embodiment, the first end A, the second end B, the third end C and the fourth end D are respectively provided with internal threads, and the connecting rod 101 and the supporting structure 105 have external threads that cooperate with the internal threads; or

[0038] The first end A, the second end B, the third end C and the fourth end D are respectively provided with external threads, and the connecting rod 101 and the supporting structure 105 have internal threads that cooperate with the external threads. The two ends of the connecting rod 101 can have internal threads and external threads respectively. Figure 1 The structure in which the first end A, the second end B, the third end C and the fourth end D are provided with internal threads is shown, one end of the connecting rod 101 has external threads connected to the second connecting member 1032, and the other end of the connecting rod 101 has internal threads connected to the external threads of another connecting rod 101. The first end A, the second end B, the third end C and the fourth end D can also be provided with external threads, which can be connected to the end of the connecting rod 101 with internal threads.

[0039] In some optional implementations of this embodiment, multiple protrusions F extend from one side of the bottom plate E in different directions, and the multiple protrusions F are detachably connected to the connecting rod 101. The detachable connection can be a connection method such as a buckle or a thread. The connecting rods can be freely combined to realize various spatial structures.

[0040] In some optional implementations of the present embodiment, one end of the plurality of protrusions F away from the base plate E has an internal thread, and the connecting rod 101 has an external thread that cooperates with the internal thread; or one end of the protrusion F away from the base plate E has an external thread, and the connecting rod 101 has an internal thread that cooperates with the internal thread. Figure 1 The structure in which the plurality of protrusions F have internal threads is shown, one end of the connecting rod 101 has external threads connected to the first connecting member 1031, and the other end of the connecting rod 101 has internal threads connected to the external threads of another connecting rod 101. The plurality of protrusions F may also be structures provided with external threads, which can be connected to one end of the connecting rod 101 having internal threads.

[0041] In some optional implementations of the present embodiment, the cross-shaped body of the second connecting member 1032 has a first threaded through hole in a third direction, the base plate E of the first connecting member 1031 has a second threaded through hole, the fastener has a third threaded protrusion, the first threaded through hole and the second threaded through hole are respectively cooperated and connected with the third threaded protrusion, and the third direction is respectively perpendicular to the first direction and the second direction of the cross-shaped body.

[0042] In some optional implementations of this embodiment, the plurality of protrusions F extend in a direction away from the axis of the second threaded through hole to prevent the connecting rods from crossing.

[0043] In some optional implementations of this embodiment, the angle between the extension direction of the plurality of protrusions and the axis direction of the second threaded through hole is the same, which can be set to 45 degrees, so that the points of the light source form a cube, thereby facilitating the calculation of the camera extrinsic parameters.

[0044] In some optional implementations of this embodiment, multiple light sources 102 are evenly spaced on the connecting rod 101, and the multiple light sources 102 on the connecting rod 101 are connected in series through wires to access a power source. For example, two light sources may be provided on a connecting rod. Figure 1 There are four light sources in the two connecting rods connected to each other in the same direction, and these four light sources can be connected in series to the same power supply.

[0045] In some optional implementations of this embodiment, the ends of the wires include wiring terminals, and the wires on different connecting rods are connected in series through the wiring terminals, so that the light sources on different connecting rods are connected in series, and all the light sources connected in series can be controlled by controlling one power supply.

[0046] In some optional implementations of this embodiment, the power supply includes a wireless communication module, different connecting rods use different power supplies, and the controller is respectively connected to the wireless communication modules of different power supplies. The light sources can be remotely controlled in groups according to user needs.

[0047] In some optional implementations of this embodiment, the light sources are evenly spaced on the connecting rods, the light sources include batteries and wireless communication modules, and the light sources are connected to the controller through the wireless communication modules. Each light source can be controlled independently, and a unique number can be set for each connecting rod in advance, and the light sources on the connecting rods also have unique numbers. The controller can control the flashing frequency of each light source individually, for example, controlling the light source numbered 01 on each connecting rod to flash twice per second, and controlling the light source numbered 02 on each connecting rod to flash three times per second. Or control all light sources on the connecting rods numbered 01 and 03 to flash twice per second, and control all light sources on the connecting rods numbered 02 and 04 to flash three times per second.

[0048] In some optional implementations of this embodiment, the connecting rod is made of carbon fiber material. Carbon fiber material is light in weight, high in tensile strength, and easy to carry.

[0049] The connecting rod, light source, multi-directional connector, controller, and support structure of the camera calibration bracket can be placed in a high-protection storage box, and the entire set of equipment can be easily carried to various sites for calibration. It takes only 10 minutes from taking out the box to completing the assembly.

[0050] Continue to refer Figure 3 , shows a process 300 of an embodiment of a camera calibration method according to the present disclosure. The camera calibration method comprises the following steps:

[0051] Step 301, according to the points required for calculating the camera external parameters, send an instruction to the controller in the camera calibration bracket to control the flashing frequency of the light source at the corresponding point in the bracket.

[0052] In this embodiment, the execution subject of the camera calibration method (for example Figure 1 The processor shown in the figure can send a command to control the flashing frequency of the light source at the corresponding point in the bracket through a wired connection or a wireless connection. If the light source is an active light source, the command is sent to the power supply, and if the light source is a passive light source, the command is sent to the wireless communication module of the light source. The processor needs to construct a triangle based on the position of the camera and the positions of multiple light sources to calculate the camera external parameters.

[0053] Step 302: Control the camera to capture an image of the light source.

[0054] In this embodiment, after the light source is turned on, the camera may be notified to start collecting images of the light source. The processor and the camera are connected to each other by wired connection or wireless connection.

[0055] Step 303, calculating the camera extrinsic parameters according to the actual distance between the light sources and the image.

[0056] In this embodiment, the measured distance between the light sources in the image is calculated, and the rotation matrix and translation matrix of the camera are calculated based on the camera extrinsic parameter calculation method of the prior art according to the measured distance, actual spacing and other parameters to obtain the camera extrinsic parameters.

[0057] The method provided by the above-mentioned embodiments of the present disclosure breaks through the limitations of traditional planar calibration plates and provides a true three-dimensional calibration point distribution. Through a connectable modular design, it can adapt to various calibration needs from small laboratories to large outdoor scenes. By using light spots at different positions, accurate depth and scale information is provided to the event camera, significantly improving the accuracy of monocular depth estimation. It can be assembled into various three-dimensional structures to achieve coverage of the camera's full field of view, solving the problem of limited viewing angle of the planar calibration plate. It overcomes the limitations of the screen size of traditional methods in large scenes, and achieves long-distance precise calibration through high-brightness light spots.

[0058] In some optional implementations of this embodiment, the method further includes: sending an instruction to the controller to adjust the brightness of the light source according to the ambient brightness, so as to improve the difference between the brightness of the light source and the current ambient brightness, maintain good imaging effects under various lighting conditions, and reduce ambient light interference.

[0059] In some optional implementations of this embodiment, the method further includes: sending an instruction to the controller to adjust the flashing frequency of the light source according to the application scenario of the camera. Using a programmable flashing mode, a complex dynamic three-dimensional environment can be simulated to improve the calibration accuracy in practical applications.

[0060] Further references Figure 4 As an implementation of the methods shown in the above figures, the present disclosure provides an embodiment of a camera calibration device. Figure 3 Corresponding to the method embodiment shown, the device can be specifically applied to various electronic devices.

[0061] like Figure 4 As shown, the camera calibration device 400 of this embodiment includes: a light source control unit 401, an image acquisition unit 402 and an extrinsic parameter calculation unit 403. Among them, the light source control unit 401 is configured to send an instruction to control the light source of the corresponding point in the bracket to the controller in the camera calibration bracket according to the point required for calculating the camera extrinsic parameter; the image acquisition unit 402 is configured to control the camera to collect the image of the light source; the extrinsic parameter calculation unit 403 is configured to calculate the camera extrinsic parameter according to the actual distance between the light sources and the image.

[0062] In this embodiment, the specific processing of the light source control unit 401, the image acquisition unit 402 and the external parameter calculation unit 403 of the camera calibration device 400 can be referred to. Figure 3 This corresponds to step 301 to step 303 in the embodiment.

[0063] In some optional implementations of this embodiment, the light source control unit 401 is further configured to: send an instruction for adjusting the brightness of the light source to the controller according to the ambient brightness.

[0064] In some optional implementations of this embodiment, the light source control unit 401 is further configured to: send an instruction for controlling the flashing mode of the light source to the controller according to an application scenario of the camera.

[0065] In the technical solution of the present disclosure, the collection, storage, use, processing, transmission, provision and disclosure of user personal information involved are in compliance with the provisions of relevant laws and regulations and do not violate public order and good morals.

[0066] According to an embodiment of the present disclosure, the present disclosure also provides an electronic device, a readable storage medium and a computer program product.

[0067] An electronic device comprises: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the method described in process 300.

[0068] A non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions are used to cause the computer to execute the method described in process 300.

[0069] A computer program product includes a computer program, and when the computer program is executed by a processor, the method described in process 300 is implemented.

[0070] Figure 5 A schematic block diagram of an example electronic device 500 that can be used to implement an embodiment of the present disclosure is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present disclosure described and / or required herein.

[0071] like Figure 5 As shown, the device 500 includes a computing unit 501, which can perform various appropriate actions and processes according to a computer program stored in a read-only memory (ROM) 502 or a computer program loaded from a storage unit 508 into a random access memory (RAM) 503. In the RAM 503, various programs and data required for the operation of the device 500 can also be stored. The computing unit 501, the ROM 502, and the RAM 503 are connected to each other via a bus 504. An input / output (I / O) interface 505 is also connected to the bus 504.

[0072] A number of components in the device 500 are connected to the I / O interface 505, including: an input unit 506, such as a keyboard, a mouse, etc.; an output unit 507, such as various types of displays, speakers, etc.; a storage unit 508, such as a disk, an optical disk, etc.; and a communication unit 509, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 509 allows the device 500 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0073] The computing unit 501 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the computing unit 501 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, digital signal processors (DSPs), and any appropriate processors, controllers, microcontrollers, etc. The computing unit 501 performs the various methods and processes described above, such as the camera calibration method. For example, in some embodiments, the camera calibration method may be implemented as a computer software program, which is tangibly contained in a machine-readable medium, such as a storage unit 508. In some embodiments, part or all of the computer program may be loaded and / or installed on the device 500 via the ROM 502 and / or the communication unit 509. When the computer program is loaded into the RAM 503 and executed by the computing unit 501, one or more steps of the camera calibration method described above may be performed. Alternatively, in other embodiments, the computing unit 501 may be configured to perform the camera calibration method in any other appropriate manner (e.g., by means of firmware).

[0074] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0075] The program code for implementing the method of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that the program code, when executed by the processor or controller, enables the functions / operations specified in the flow chart and / or block diagram to be implemented. The program code may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0076] In the context of the present disclosure, a machine-readable medium may be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, device, or equipment. A machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or equipment, or any suitable combination of the foregoing. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0077] To provide interaction with a user, the systems and techniques described herein can be implemented on a computer having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user can provide input to the computer. Other types of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic input, voice input, or tactile input).

[0078] The systems and techniques described herein may be implemented in a computing system that includes back-end components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes front-end components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such back-end components, middleware components, or front-end components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), and the Internet.

[0079] A computer system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The relationship of client and server is generated by computer programs running on respective computers and having a client-server relationship with each other. The server may be a cloud server, a server of a distributed system, or a server combined with a blockchain.

[0080] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps recorded in this disclosure can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solutions disclosed in this disclosure can be achieved, and this document does not limit this.

[0081] The above specific implementations do not constitute a limitation on the protection scope of the present disclosure. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A camera calibration bracket, comprising: Connecting rod; A light source is arranged on the connecting rod; A multi-directional connecting member connected to a plurality of connecting rods extending in different directions; A controller, used to control the flashing frequency of the light source; A supporting structure is connected to the multi-directional connecting member and is used to support the multiple connecting rods.

2. The bracket according to claim 1, wherein: The multi-directional connector includes a first connector; The first connecting member includes a bottom plate and a plurality of protrusions arranged on one side of the bottom plate, and ends of the plurality of protrusions away from the bottom plate are respectively connected to different connecting rods.

3. The bracket according to claim 1, wherein: The multi-directional connector includes a second connector, The second connecting member includes a cross-shaped body having a first end and a second end opposite to each other in the first direction, and a third end and a fourth end opposite to each other in the second direction; Wherein, the first end, the second end and the third end are respectively connected to different connecting rods, the fourth end is connected to the supporting structure, and the first direction and the second direction are perpendicular to each other.

4. The bracket according to claim 1, wherein: The multi-directional connector includes a second connector, at least one first connector and a fastener; The second connecting member comprises a cross-shaped body, the cross-shaped body having a first end and a second end opposite to each other in a first direction, and a third end and a fourth end opposite to each other in a second direction; wherein the first end, the second end and the third end are respectively connected to different connecting rods, the fourth end is connected to the supporting structure, and the first direction and the second direction are perpendicular to each other; The first connecting member includes a bottom plate and a plurality of protrusions arranged on one side of the bottom plate, and ends of the plurality of protrusions away from the bottom plate are respectively connected to different connecting rods; The second connecting member is arranged on a side of the at least one first connecting member away from the protruding portion, and is connected to the at least one first connecting member through the fastener.

5. The bracket according to claim 3 or 4, wherein: The first end, the second end and the third end are detachably connected to the connecting rod respectively, and the fourth end is detachably connected to the supporting structure.

6. The bracket according to claim 5, wherein: The first end, the second end, the third end and the fourth end are respectively provided with internal threads, and the connecting rod and the supporting structure have external threads that cooperate with the internal threads; or The first end, the second end, the third end and the fourth end are respectively provided with external threads, and the connecting rod and the supporting structure have internal threads that are matched and connected with the external threads.

7. The bracket according to claim 2 or 4, wherein: The plurality of protrusions extend from one side of the bottom plate in different directions, and the plurality of protrusions are detachably connected to the connecting rod.

8. The bracket according to claim 7, wherein: One end of the plurality of protrusions away from the bottom plate has an internal thread, and the connecting rod has an external thread that cooperates with the internal thread; or The end of the protrusion away from the bottom plate has an external thread, and the connecting rod has an internal thread that cooperates with the internal thread.

9. The bracket according to claim 4, wherein: The cross-shaped body of the second connecting member has a first threaded through hole in a third direction, and a second threaded through hole is provided on the bottom plate of the first connecting member. The fastener has a third threaded protrusion, and the first threaded through hole and the second threaded through hole are respectively cooperated and connected with the third threaded protrusion, and the third direction is respectively perpendicular to the first direction and the second direction of the cross-shaped body.

10. The bracket according to claim 9, wherein: The plurality of protrusions extend in a direction away from an axis of the second threaded through hole.

11. The bracket according to claim 9, wherein: The extending directions of the plurality of protrusions have the same included angle as the axial direction of the second threaded through hole.

12. The bracket according to claim 1, wherein: The multiple light sources are distributed on the connecting rod at equal intervals, and the multiple light sources on the connecting rod are connected in series through electric wires and connected to a power source.

13. The bracket according to claim 12, wherein: The ends of the electric wires include connection terminals, and the electric wires on different connecting rods are connected in series through the connection terminals.

14. The bracket according to claim 12, wherein: The power source includes a wireless communication module, different connecting rods use different power sources, and the controller is respectively connected to the wireless communication modules of different power sources for communication.

15. The bracket according to claim 1, wherein: The light sources are distributed on the connecting rod at equal intervals. The light sources include a battery and a wireless communication module. The light sources are communicatively connected with the controller via the wireless communication module.

16. The bracket according to claim 1, wherein the connecting rod is made of carbon fiber material.

17. A camera calibration method, comprising: According to the points required for calculating the camera extrinsic parameters, an instruction for controlling the flashing frequency of the light source at the corresponding point in the bracket is sent to a controller in the camera calibration bracket according to any one of claims 1 to 16; Controlling a camera to collect an image of the light source; The camera extrinsic parameters are calculated according to the actual distance between the light sources and the image.

18. The method according to claim 17, wherein: The method further comprises: An instruction for adjusting the brightness of the light source is sent to the controller according to the ambient brightness.

19. The method according to claim 17, wherein: The method further comprises: An instruction for adjusting the flashing frequency of the light source is sent to the controller according to an application scenario of the camera.

20. A camera calibration system, comprising: The camera to be calibrated; A camera calibration bracket according to any one of claims 1 to 16; A processor, configured to execute the camera calibration method according to any one of claims 17 to 19.

21. A camera calibration device, comprising: A light source control unit, configured to send an instruction to control the light source of the corresponding point in the camera calibration bracket to the controller in the bracket according to any one of claims 1 to 16 according to the point required for calculating the camera external parameters; An image acquisition unit, configured to control a camera to acquire an image of the light source; The extrinsic parameter calculation unit is configured to calculate the camera extrinsic parameters according to the actual distance between the light sources and the image.

22. The device according to claim 21, wherein The light source control unit is further configured to: An instruction for adjusting the brightness of the light source is sent to the controller according to the ambient brightness.

23. The device according to claim 22, wherein: The light source control unit is further configured to: An instruction for controlling the flashing mode of the light source is sent to the controller according to an application scenario of the camera.

24. An electronic device comprising: at least one processor; as well as a memory communicatively connected to the at least one processor; wherein, The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method according to any one of claims 17 to 19.

25. A non-transitory computer-readable storage medium storing computer instructions, wherein: The computer instructions are used to cause the computer to execute the method according to any one of claims 17-19.

26. A computer program product comprising a computer program, which, when executed by a processor, implements the method according to any one of claims 17 to 19.

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