Calibration device, camera calibration method and apparatus, device, and storage medium

Abstract

Disclosed in the present application are a calibration device, a camera calibration method and apparatus, a device, and a storage medium. The calibration device comprises: a first calibration plate, a first plane of the first calibration plate being rectangular; and a second calibration plate, a third calibration plate, a fourth calibration plate, and a fifth calibration plate, second planes of the second calibration plate, the third calibration plate, the fourth calibration plate, and the fifth calibration plate each being connected to a second plane of the first calibration plate. Included angles between first planes of the second calibration plate, the third calibration plate, the fourth calibration plate, and the fifth calibration plate and the first plane of the first calibration plate are a target angle, the second planes are four planes adjacent to the first plane, and the target angle is an obtuse angle. The first planes of the first calibration plate, the second calibration plate, the third calibration plate, the fourth calibration plate, and the fifth calibration plate each include position information for camera calibration. In this way, camera calibration is carried out on the basis of the described calibration device, improving the efficiency and accuracy of camera calibration.

Description

Calibration equipment, camera calibration method, device, equipment and storage medium

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on July 28, 2023, with application number 202310943576.0 and invention name “Calibration device, camera calibration method, apparatus, device and storage medium”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application belongs to the field of camera calibration technology, and in particular relates to a calibration device, a camera calibration method, an apparatus, a device, and a storage medium. Background Art

[0003] Camera calibration is the process of calculating and correcting the camera's internal and external parameters. This improves the accuracy of camera imaging and is of great significance to fields such as machine vision and 3D modeling. Currently, camera calibration is mainly divided into calibration based on a plane model and calibration based on a spherical model.

[0004] However, existing camera calibration methods require multiple images to obtain relatively accurate camera calibration data, and require manual collection of chessboard images in different postures for calibration. This makes the camera calibration process more cumbersome and prone to errors, and the efficiency and accuracy of camera calibration are low.

[0005] Summary of the Invention

[0006] The embodiments of the present application provide a calibration device, a camera calibration method, an apparatus, a device, and a storage medium, which improve the efficiency and accuracy of camera calibration.

[0007] In a first aspect, an embodiment of the present application provides a calibration method for camera calibration, including:

[0008] A first calibration plate, wherein the first plane of the first calibration plate is rectangular;

[0009] a second calibration plate, a third calibration plate, a fourth calibration plate, and a fifth calibration plate, wherein the second planes of the second calibration plate, the third calibration plate, the fourth calibration plate, and the fifth calibration plate are respectively connected to the second plane of the first calibration plate, and the angles between the first planes of the second calibration plate, the third calibration plate, the fourth calibration plate, and the fifth calibration plate and the first plane of the first calibration plate are target angles, the second planes are four planes adjacent to the first plane, and the target angles are obtuse angles;

[0010] The first planes of the first calibration plate, the second calibration plate, the third calibration plate, the fourth calibration plate and the fifth calibration plate respectively include position information for camera calibration.

[0011] In one possible embodiment, the target angle is 120°.

[0012] In one possible embodiment, the position information used for camera calibration includes position information calibrated in a checkerboard format.

[0013] In a second aspect, an embodiment of the present application provides a camera calibration method based on the calibration device for camera calibration, including:

[0014] Obtaining an image within the camera's field of view and the distance between the camera and a calibration device, where the calibration device is the calibration device used for camera calibration described above;

[0015] Determining the size of the calibration device according to the image within the camera field of view and the distance between the camera and the calibration device, and obtaining a target image within the camera field of view, wherein the size of the calibration device is larger than the size of the target image within the camera field of view, and the calibration device is located at the center of the target image;

[0016] Controlling the camera to capture an image to obtain a first image;

[0017] Extracting position information for camera calibration from the first image;

[0018] The camera is calibrated according to the position information and the position information on the calibration device used for camera calibration to obtain camera parameters.

[0019] In one possible embodiment, the position information used for camera calibration includes position information calibrated in a checkerboard format, and extracting the position information used for camera calibration from the first image includes:

[0020] Determine the position information of the first corner point of the checkerboard in the first image by using a non-maximum suppression algorithm;

[0021] Calculate the gradient magnitude and direction of the first corner point;

[0022] The gradient magnitude and direction of the first corner point are used to determine the coordinates of the second corner point, thereby obtaining the position information of the second corner point.

[0023] In one possible embodiment, before determining the first corner point of the checkerboard in the first image using the non-maximum suppression algorithm, the method further includes:

[0024] Performing Gaussian filtering on the first image to obtain a second image;

[0025] Determining position information of a first corner point of a checkerboard in a first image by using a non-maximum suppression algorithm includes:

[0026] The non-maximum suppression algorithm is used to determine the position information of the first corner point of the chessboard in the second image.

[0027] In one possible embodiment, the camera is calibrated based on the position information and the position information used for camera calibration on the calibration device to obtain camera parameters, including:

[0028] Determine the pixel coordinates of the second corner point using the checkerboard of the second image and the position information of the second corner point;

[0029] Calculate the world coordinates of the second corner point based on the checkerboard on the calibration device;

[0030] The camera's intrinsic and extrinsic parameters and distortion parameters are calculated using pixel coordinates and world coordinates.

[0031] In a third aspect, an embodiment of the present application provides a camera calibration device, comprising:

[0032] An acquisition module, used to acquire the image within the camera's field of view and the distance between the camera and a calibration device, where the calibration device is the calibration device used for camera calibration mentioned above;

[0033] a determination module, configured to determine a size of a calibration device based on an image within the camera field of view and a distance between the camera and the calibration device, to obtain a target image within the camera field of view, wherein the size of the calibration device is larger than the size of the target image within the camera field of view, and the calibration device is located at the center of the target image;

[0034] A control module, configured to control the camera to capture an image and obtain a first image;

[0035] an extraction module, configured to extract position information for camera calibration from the first image;

[0036] The determination module is further used to calibrate the camera according to the position information and the position information used for camera calibration on the calibration device to obtain camera parameters.

[0037] In a fourth aspect, an embodiment of the present application provides an electronic device, the device comprising:

[0038] a processor and a memory storing computer program instructions;

[0039] When the processor executes the computer program instructions, it implements any one of the above-mentioned camera calibration methods.

[0040] In a fifth aspect, an embodiment of the present application provides a computer storage medium, on which computer program instructions are stored. When the computer program instructions are executed by a processor, any one of the above-mentioned camera calibration methods is implemented.

[0041] In a sixth aspect, an embodiment of the present application provides a computer program product, characterized in that when the instructions in the computer program product are executed by a processor of an electronic device, the electronic device is enabled to perform any of the above-mentioned camera calibration methods.

[0042] The calibration device, camera calibration method, apparatus, device, and storage medium of the embodiments of the present application include: a first calibration plate, wherein the first plane of the first calibration plate is rectangular; a second calibration plate, a third calibration plate, a fourth calibration plate, and a fifth calibration plate; the second planes of the second calibration plate, the third calibration plate, the fourth calibration plate, and the fifth calibration plate are respectively connected to the second plane of the first calibration plate; the angles between the first planes of the second calibration plate, the third calibration plate, the fourth calibration plate, and the fifth calibration plate and the first plane of the first calibration plate are target angles; the second planes are four planes adjacent to the first plane; the target angles are obtuse angles; wherein the first planes of the first calibration plate, the second calibration plate, the third calibration plate, the fourth calibration plate, and the fifth calibration plate respectively include position information for camera calibration. Thus, a calibration device based on five calibration plates at different angles is used to perform camera calibration, thereby avoiding the tedious and error-prone process of manually collecting images of the calibration device in different postures for calibration, thereby improving the efficiency and accuracy of camera calibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0044] FIG1 is a schematic structural diagram of a calibration device for camera calibration provided by one embodiment of the present application;

[0045] FIG2 is a schematic structural diagram of a calibration device for camera calibration provided in another embodiment of the present application;

[0046] FIG3 is a flowchart of a camera calibration method provided in yet another embodiment of the present application;

[0047] FIG4 is a schematic diagram of a scene of a camera calibration method according to another embodiment of the present application;

[0048] FIG5 is a schematic structural diagram of a camera calibration device provided in yet another embodiment of the present application;

[0049] FIG6 is a schematic structural diagram of an electronic device provided in yet another embodiment of the present application. DETAILED DESCRIPTION

[0050] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is merely to provide a better understanding of the present application by illustrating the examples of the present application.

[0051] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, the elements defined by the phrase "comprising..." do not exclude the presence of other identical elements in the process, method, article, or device comprising the elements.

[0052] Camera calibration is the process of calculating and correcting the camera's internal and external parameters. This improves the accuracy of camera imaging and is of great significance to fields such as machine vision and 3D modeling. Currently, camera calibration is mainly divided into calibration based on a plane model and calibration based on a spherical model.

[0053] However, existing camera calibration methods require multiple images to obtain relatively accurate camera calibration data, and require manual collection of chessboard images in different postures for calibration. This makes the camera calibration process more cumbersome and prone to errors, and the efficiency and accuracy of camera calibration are low.

[0054] In order to solve the problems of the prior art, the embodiments of the present application provide a calibration device, a camera calibration method, an apparatus, a device, and a storage medium. The following first introduces the calibration device for camera calibration provided in the embodiments of the present application.

[0055] FIG1 shows a schematic structural diagram of a calibration device for camera calibration provided in one embodiment of the present application.

[0056] As shown in FIG1 , an embodiment of the present application provides a calibration device for camera calibration, including:

[0057] A first calibration plate 110, wherein the first plane of the first calibration plate 110 is rectangular;

[0058] The second calibration plate 120, the third calibration plate 130, the fourth calibration plate 140 and the fifth calibration plate 150, the second planes of the second calibration plate 120, the third calibration plate 130, the fourth calibration plate 140 and the fifth calibration plate 150 are respectively connected to the second plane of the first calibration plate 110, and the angles between the first planes of the second calibration plate 120, the third calibration plate 130, the fourth calibration plate 140 and the fifth calibration plate 150 and the first plane of the first calibration plate 110 are target angles, the second planes are four planes adjacent to the first plane, and the target angles are obtuse angles;

[0059] The first planes of the first calibration plate 110 , the second calibration plate 120 , the third calibration plate 130 , the fourth calibration plate 140 and the fifth calibration plate 150 respectively include position information for camera calibration.

[0060] In some embodiments, the first calibration plate 110, the second calibration plate 120, the third calibration plate 130, the fourth calibration plate 140, and the fifth calibration plate 150 can be made of wood, plastic, or iron. A bracket can be used to secure the first calibration plate 110, and the second calibration plate 120, the third calibration plate 130, the fourth calibration plate 140, and the fifth calibration plate 150 can be connected to the first calibration plate 110, respectively, thereby securing the entire calibration device. It should be noted that by using the calibration device to correspond points in the calibration device with points in the image, camera intrinsic and extrinsic parameters and distortion parameters can be calculated, thereby achieving camera calibration.

[0061] In some embodiments, the calibration device is located at the center of the camera's field of view, for example, the line between the center point of the camera's field of view and the center point of the first calibration plate 110 of the calibration device is parallel to the horizontal plane, and the camera's field of view is parallel to the first calibration plate 110.

[0062] In this way, a calibration device composed of calibration plates at five different angles is used to calibrate the camera, avoiding the tedious and error-prone process of manually collecting images of the calibration device in different postures for calibration, thereby improving the efficiency and accuracy of camera calibration.

[0063] Based on this, in some embodiments, the target angle may be 120°.

[0064] In some embodiments, the angles between the first planes of the second calibration plate 120 , the third calibration plate 130 , the fourth calibration plate 140 , and the fifth calibration plate 150 and the first plane of the first calibration plate 110 are 120°.

[0065] In this way, the angle between the camera's field of view and each calibration plate is different. Using this calibration device for camera calibration avoids the tedious and error-prone process of manually collecting images of the calibration device in different postures for calibration, thereby improving the efficiency and accuracy of camera calibration.

[0066] In some embodiments, as shown in FIG. 2 , the position information used for camera calibration may include position information calibrated in a checkerboard format.

[0067] In some embodiments, the checkerboard can be drawn on the calibration board; it can also be affixed to the calibration board in the form of cardboard or paper; it can also be engraved on the calibration board; or it can be a checkerboard composed of components of two different colors, and the components are located on the first plane of the calibration board.

[0068] In some embodiments, the size of the calibration device, the size of the checkerboard grid, and the number of grids are determined by the camera's field of view. For each calibration plate, the number of checkerboard grids within the camera's field of view must be greater than or equal to 5*5, and the grid size must meet the camera's image clarity requirements. The calibration device must be larger than the target image within the camera's field of view.

[0069] In this way, the position information calibrated in the form of a checkerboard can more accurately extract the position information in the image, thereby improving the efficiency and accuracy of camera calibration.

[0070] Based on the calibration device for camera calibration provided in the above embodiments, this application also provides a specific implementation of a camera calibration method. Please refer to the following embodiments.

[0071] FIG3 shows a flowchart of a camera calibration method provided by an embodiment of the present application.

[0072] As shown in FIG3 , an embodiment of the present application provides a camera calibration method based on the calibration device for camera calibration, including S110 to S150 .

[0073] S110: Acquire an image within the camera's field of view and the distance between the camera and the calibration device.

[0074] Here, the distance between the camera and the calibration device is fixed by the user. After the distance between the camera and the calibration device is fixed, the camera can focus and capture clear images when shooting the calibration device at this distance. The calibration device is the calibration device used for camera calibration mentioned above.

[0075] In some embodiments, the distance between the camera and the calibration device, as input by the user, and the image within the camera's field of view at that time are obtained. The image reflects the camera's field of view and includes information about objects within the range that the camera can capture, that is, including the calibration device.

[0076] S120. Determine the size of the calibration device according to the image within the camera field of view and the distance between the camera and the calibration device, and obtain a target image within the camera field of view, wherein the size of the calibration device is larger than the size of the target image within the camera field of view, and the calibration device is located at the center of the target image.

[0077] In some embodiments, the size of the calibration device is determined based on the principle that the size of the calibration device is larger than the size of the target image within the camera's field of view. After the size of the calibration device is determined, the image within the camera's field of view is changed to obtain the target image within the camera's field of view. The calibration device is located at the center of the target image.

[0078] As an example, as shown in FIG4 , the size of the calibration device is larger than the size of the target image within the camera field of view, and the calibration device is located at the center of the target image.

[0079] S130: Control the camera to capture an image to obtain a first image.

[0080] Here, the first image coincides with the image of the target within the camera's field of view.

[0081] In some embodiments, after obtaining an image of a target within the camera's field of view, the camera is controlled to capture an image to obtain a first image, which includes a calibration device.

[0082] S140: Extracting position information for camera calibration from the first image.

[0083] In some embodiments, the calibration device includes position information for camera calibration, and the position information for camera calibration can be extracted from the first image.

[0084] S150: Calibrate the camera according to the position information and the position information on the calibration device used for camera calibration to obtain camera parameters.

[0085] In some embodiments, the Zhang Zhengyou calibration method can be used to calibrate the camera based on the position information used for camera calibration in the first image and the position information used for camera calibration on the calibration device to obtain camera parameters.

[0086] In this way, the calibration device composed of calibration plates at five different angles determines the size of the calibration device according to the image within the camera's field of view and the distance between the camera and the calibration device. Using the calibration device, clear images of the calibration device are collected to perform camera calibration, avoiding the tedious and error-prone process of manually collecting images of the calibration device in different postures for calibration, thereby improving the efficiency and accuracy of camera calibration.

[0087] Based on this, in some embodiments, the position information used for camera calibration includes position information calibrated in a checkerboard format, and the above S140 may specifically include:

[0088] Determine the position information of the first corner point of the checkerboard in the first image by using a non-maximum suppression algorithm;

[0089] Calculate the gradient magnitude and direction of the first corner point;

[0090] The gradient magnitude and direction of the first corner point are used to determine the coordinates of the second corner point, thereby obtaining the position information of the second corner point.

[0091] The non-maximum suppression algorithm, commonly used in computer vision for edge detection, object recognition, face recognition, and target detection, is an algorithm that searches for local maxima and suppresses non-maxima. Corner points can effectively reduce the amount of data while preserving important image features, resulting in a high level of information content and significantly improving computational speed. It should be noted that the corner points of a checkerboard are the four vertices of each black checkerboard square.

[0092] In some embodiments, a non-maximum suppression algorithm is used to coarsely locate the coordinates of a checkerboard corner in the first image, obtaining position information of a first corner of the checkerboard. The gradient magnitude and direction of the first corner are calculated. The gradient magnitude and direction of the first corner are then used to refine the coordinates of the first corner using sub-pixel resolution, i.e., determine the coordinates of a second corner, obtaining position information of the second corner.

[0093] In this way, after roughly locating the corner point coordinates, the gradient amplitude and direction of the corner point are used to refine the corner point coordinates, thereby obtaining the position information of the corner point more accurately, thereby improving the accuracy of camera calibration.

[0094] Based on this, in some embodiments, before determining the first corner point of the checkerboard in the first image using the non-maximum suppression algorithm, the method further includes:

[0095] Performing Gaussian filtering on the first image to obtain a second image;

[0096] Determining position information of a first corner point of a checkerboard in a first image by using a non-maximum suppression algorithm includes:

[0097] The non-maximum suppression algorithm is used to determine the position information of the first corner point of the chessboard in the second image.

[0098] In some embodiments, Gaussian filtering is performed on the first image to obtain a smoothed image, that is, the second image is a smoothed image.

[0099] In this way, by filtering the first image and then extracting the corner points, the position information of the corner points can be obtained more accurately, thereby improving the accuracy of camera calibration.

[0100] Based on this, in some embodiments, the above S150 may specifically include:

[0101] Determine the pixel coordinates of the second corner point using the checkerboard of the second image and the position information of the second corner point;

[0102] Calculate the world coordinates of the second corner point based on the checkerboard on the calibration device;

[0103] The camera's intrinsic and extrinsic parameters and distortion parameters are calculated using pixel coordinates and world coordinates.

[0104] In some embodiments, it is determined whether the number of checkerboard squares is greater than 25 (5*5). If so, the intrinsic and extrinsic parameters and distortion parameters of the camera are calculated using pixel coordinates and world coordinates; if not, the camera calibration is abandoned.

[0105] In some embodiments, the pixel coordinates of the second corner point are determined using the size of the checkerboard of the second image and the position information of the second corner point, and the world coordinates of the second corner point are calculated according to the size of the checkerboard on the calibration device.

[0106] In some embodiments, the pixel coordinates of each second corner point on the second image are matched one-to-one with the world coordinates of the second corner point on the calibration device, and the camera is calibrated using the Zhang Zhengyou calibration method to obtain the intrinsic and extrinsic parameters and distortion parameters of the camera.

[0107] In this way, the corner points on the image are matched one-to-one with the corner points on the calibration device, and the camera calibration can be performed using the Zhang Zhengyou calibration method.

[0108] Based on the camera calibration method based on the calibration device for camera calibration provided in the above embodiment, the present application also provides a specific implementation of a camera calibration device. Please refer to the following embodiments.

[0109] First, referring to FIG5 , a camera calibration device 500 provided in an embodiment of the present application includes:

[0110] An acquisition module 510 is used to acquire an image within the camera's field of view and the distance between the camera and the calibration device;

[0111] a determination module 520 for determining a size of a calibration device based on the image within the camera field of view and the distance between the camera and the calibration device, to obtain a target image within the camera field of view, wherein the size of the calibration device is larger than the size of the target image within the camera field of view, and the calibration device is located at the center of the target image;

[0112] A control module 530 is used to control the camera to capture an image and obtain a first image;

[0113] An extraction module 540 is configured to extract position information for camera calibration from the first image;

[0114] The determination module 520 is further configured to calibrate the camera according to the position information and the position information on the calibration device used for camera calibration to obtain camera parameters.

[0115] Based on this, in some embodiments, the position information used for camera calibration includes position information calibrated in a checkerboard format, and the extraction module 540 can be specifically used to:

[0116] Determine the position information of the first corner point of the checkerboard in the first image by using a non-maximum suppression algorithm;

[0117] Calculate the gradient magnitude and direction of the first corner point;

[0118] The gradient magnitude and direction of the first corner point are used to determine the coordinates of the second corner point, thereby obtaining the position information of the second corner point.

[0119] Based on this, in some embodiments, the apparatus 500 may further include:

[0120] The filtering module is further configured to perform Gaussian filtering on the first image to obtain a second image before determining the first corner point of the checkerboard in the first image using a non-maximum suppression algorithm;

[0121] The extraction module 540 may be specifically used to:

[0122] The non-maximum suppression algorithm is used to determine the position information of the first corner point of the chessboard in the second image.

[0123] Based on this, in some embodiments, the determination module 520 may be specifically configured to:

[0124] Determine the pixel coordinates of the second corner point using the checkerboard of the second image and the position information of the second corner point;

[0125] Calculate the world coordinates of the second corner point based on the checkerboard on the calibration device;

[0126] The camera's intrinsic and extrinsic parameters and distortion parameters are calculated using pixel coordinates and world coordinates.

[0127] The various modules of the camera calibration device provided in the embodiment of the present application can implement the functions of the various steps of the camera calibration method provided in Figure 3 and achieve the corresponding technical effects. For the sake of brevity, they are not repeated here.

[0128] Based on the same inventive concept, an embodiment of the present application also provides an electronic device.

[0129] FIG6 shows a schematic diagram of the hardware structure of an electronic device provided in an embodiment of the present application.

[0130] The electronic device may include a processor 601 and a memory 602 storing computer program instructions.

[0131] Specifically, the processor 601 may include a central processing unit (CPU) or an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the embodiments of the present application.

[0132] The memory 602 may include a large capacity memory for data or instructions. By way of example and not limitation, the memory 602 may include a hard disk drive (HDD), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a magnetic tape, or a universal serial bus (USB) drive, or a combination of two or more of these. Where appropriate, the memory 602 may include removable or non-removable (or fixed) media. Where appropriate, the memory 602 may be inside or outside the integrated gateway disaster recovery device. In a specific embodiment, the memory 602 is a non-volatile solid-state memory.

[0133] The memory may include a read-only memory (ROM), a random access memory (RAM), a magnetic disk storage medium device, an optical storage medium device, a flash memory device, an electrical, optical or other physical / tangible memory storage device. Thus, generally, the memory includes one or more tangible (non-transitory) computer-readable storage media (e.g., a memory device) encoded with software including computer-executable instructions, and when the software is executed (e.g., by one or more processors), it is operable to perform the operations described with reference to the method according to one aspect of the present application.

[0134] The processor 601 implements any one of the camera calibration methods in the above embodiments by reading and executing computer program instructions stored in the memory 602 .

[0135] In one example, the electronic device may further include a communication interface 603 and a bus 604. As shown in FIG6, the processor 601, the memory 602, and the communication interface 603 are connected via the bus 604 and communicate with each other.

[0136] The communication interface 603 is mainly used to implement communication between various modules, devices, units and / or equipment in the embodiments of the present application.

[0137] The bus 604 includes hardware, software, or both that couples components of the electronic device to each other. By way of example and not limitation, the bus may include an Accelerated Graphics Port (AGP) or other graphics bus, an Extended Industry Standard Architecture (EISA) bus, a Front Side Bus (FSB), a Hyper Transport (HT) interconnect, an Industry Standard Architecture (ISA) bus, an InfiniBand interconnect, a Linear Predictive Coding (LPC) bus, a memory bus, a MicroChannel Architecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, a PCI-Express (Peripheral Component Interconnect-X, PCI-X) bus, a Serial Advanced Technology Attachment (SATA) bus, a Video Electronics Standards Association Local Bus (VESA Local Bus, VLB) bus, or other suitable buses, or a combination of two or more of these. Where appropriate, the bus 604 may include one or more buses. Although the embodiments of the present application describe and illustrate a specific bus, the present application contemplates any suitable bus or interconnection. The electronic device can execute the camera calibration method of the embodiment of the present invention, thereby implementing the camera calibration method described in FIG3 .

[0138] In addition, in conjunction with the camera calibration method in the above embodiments, embodiments of the present application may provide a computer storage medium for implementation. The computer storage medium stores computer program instructions; when the computer program instructions are executed by a processor, any of the camera calibration methods in the above embodiments is implemented.

[0139] The present application also provides a computer program product. When the instructions in the computer program product are executed by a processor of an electronic device, the electronic device performs the various processes of any of the above-mentioned camera calibration method embodiments.

[0140] It should be understood that the present application is not limited to the specific configurations and processes described above and illustrated in the figures. For the sake of brevity, a detailed description of known methods is omitted here. In the above embodiments, several specific steps are described and illustrated as examples. However, the method process of the present application is not limited to the specific steps described and illustrated. Those skilled in the art can make various changes, modifications, and additions, or change the order of the steps after understanding the spirit of the present application.

[0141] The functional blocks shown in the above-described block diagram can be implemented as hardware, software, firmware or a combination thereof. When implemented in hardware, it can be, for example, an electronic circuit, an application specific integrated circuit (ASIC), appropriate firmware, a plug-in, a function card, etc. When implemented in software, the elements of the present application are programs or code segments used to perform the required tasks. The program or code segment can be stored in a machine-readable medium, or transmitted on a transmission medium or a communication link via a data signal carried in a carrier wave. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, read-only memories (ROMs), flash memories, erasable read-only memories (EROMs), floppy disks, compact disc read-only memories (CD-ROMs), optical discs, hard disks, optical fiber media, radio frequency (RF) links, etc. The code segments can be downloaded via computer networks such as the Internet, intranets, etc.

[0142] It should also be noted that the exemplary embodiments mentioned in this application describe some methods or systems based on a series of steps or devices. However, this application is not limited to the order of the above steps. In other words, the steps can be performed in the order mentioned in the embodiments, or in a different order, or several steps can be performed simultaneously.

[0143] Aspects of the present application have been described above with reference to the flowcharts and / or block diagrams of the methods, devices (systems) and computer program products according to the embodiments of the present application. It should be understood that each box in the flowchart and / or block diagram and the combination of each box in the flowchart and / or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer or other programmable data processing device to produce a machine so that these instructions executed via the processor of the computer or other programmable data processing device enable the implementation of the function / action specified in one or more boxes of the flowchart and / or block diagram. This processor can be, but is not limited to, a general-purpose processor, a special-purpose processor, a special application processor or a field programmable logic circuit. It is also understood that each box in the block diagram and / or the flowchart and the combination of the boxes in the block diagram and / or the flowchart can also be implemented by the dedicated hardware that performs the specified function or action, or can be implemented by the combination of dedicated hardware and computer instructions.

[0144] The above is only a specific implementation method of the present application. Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. It should be understood that the scope of protection of the present application is not limited to this. Any technician familiar with this technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in this application, and these modifications or replacements should be included in the scope of protection of this application.

Claims

1. A calibration device for camera calibration, characterized in that: include: A first calibration plate, wherein a first plane of the first calibration plate is a rectangle; A second calibration plate, a third calibration plate, a fourth calibration plate and a fifth calibration plate, wherein the second planes of the second calibration plate, the third calibration plate, the fourth calibration plate and the fifth calibration plate are respectively connected to the second plane of the first calibration plate, and the angles between the first planes of the second calibration plate, the third calibration plate, the fourth calibration plate and the fifth calibration plate and the first plane of the first calibration plate are target angles, the second planes are four planes adjacent to the first plane, and the target angle is an obtuse angle; The first planes of the first calibration plate, the second calibration plate, the third calibration plate, the fourth calibration plate and the fifth calibration plate respectively include position information for camera calibration.

2. The calibration device for camera calibration according to claim 1, characterized in that: The target angle is 120°.

3. The calibration device for camera calibration according to claim 2, characterized in that: The position information used for camera calibration includes position information calibrated in a checkerboard form.

4. A camera calibration method, characterized in that: include: Acquire an image within a camera field of view and a distance between the camera and the calibration device, wherein the calibration device is a calibration device for camera calibration according to any one of claims 1 to 3; Determining the size of the calibration device according to the image in the camera field of view and the distance between the camera and the calibration device, and obtaining the target image in the camera field of view, wherein the size of the calibration device is larger than the size of the target image in the camera field of view, and the calibration device is located at the center of the target image; Controlling the camera to capture an image to obtain a first image; Extracting position information for camera calibration from the first image; The camera is calibrated according to the position information and the position information on the calibration device used for camera calibration to obtain camera parameters.

5. The camera calibration method according to claim 4, characterized in that: The position information used for camera calibration includes position information calibrated in a checkerboard form, and the extracting the position information used for camera calibration in the first image includes: Determine the position information of the first corner point of the chessboard in the first image by using a non-maximum suppression algorithm; Calculate the gradient magnitude and direction of the first corner point; The coordinates of the second corner point are determined by using the gradient magnitude and direction of the first corner point to obtain the position information of the second corner point.

6. The camera calibration method according to claim 5, characterized in that: Before determining the first corner point of the checkerboard in the first image by using a non-maximum suppression algorithm, the method further includes: Performing Gaussian filtering on the first image to obtain a second image; The step of using a non-maximum suppression algorithm to determine the position information of the first corner point of the chessboard in the first image includes: The position information of the first corner point of the chessboard in the second image is determined by using a non-maximum suppression algorithm.

7. The camera calibration method according to claim 6, characterized in that: The camera is calibrated according to the position information and the position information used for camera calibration on the calibration device to obtain camera parameters, including: Determine the pixel coordinates of the second corner point using the checkerboard of the second image and the position information of the second corner point; Calculate the world coordinates of the second corner point according to the checkerboard on the calibration device; The pixel coordinates and the world coordinates are used to calculate the intrinsic and extrinsic parameters and the distortion parameters of the camera.

8. A camera calibration device, characterized in that: The device comprises: an acquisition module, used for acquiring an image within a camera field of view and a distance between the camera and the calibration device, wherein the calibration device is a calibration device for camera calibration according to any one of claims 1 to 3; a determination module, configured to determine the size of the calibration device according to the image in the camera field of view and the distance between the camera and the calibration device, and obtain a target image in the camera field of view, wherein the size of the calibration device is larger than the size of the target image in the camera field of view, and the calibration device is located at the center of the target image; A control module, used for controlling the camera to capture an image and obtain a first image; An extraction module, used to extract position information used for camera calibration in the first image; The determination module is also used to determine the position of the camera based on the position information and the calibration device. The camera is calibrated based on the determined position information to obtain camera parameters.

9. An electronic device, characterized in that: The device comprises: a processor and a memory storing computer program instructions; When the processor executes the computer program instructions, the camera calibration method according to any one of claims 4 to 7 is implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer program instructions, and when the computer program instructions are executed by the processor, the camera calibration method according to any one of claims 4 to 7 is implemented.

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