Camera internal reference calibration method, camera calibration method, tracking equipment and related device

Abstract

The embodiment of the invention provides a camera internal reference calibration method, a camera calibration method, tracking equipment and a related device. The camera internal reference calibration method comprises the following steps: calibrating a parameter value of at least one internal reference of a target camera in a first wave band; for at least part of the internal reference, determining a parameter value of the internal reference in a second wave band based on the parameter value of the internal reference in the first wave band and a specified corresponding relation of the internal reference between the first wave band and the second wave band; wherein the first wave band and the second wave band are non-overlapping wave bands of light. According to the invention, a rapid and convenient camera internal reference calibration scheme is provided for the target camera working in the two wavebands, and two sets of camera internal reference in the two wavebands can be obtained through one calibration process, so that the camera internal reference calibration time is saved, and the calibration cost is reduced.

Description

Technical Field

[0001] The present application relates to the field of camera calibration technology, and in particular to a camera intrinsic parameter calibration method, a camera calibration method, a tracking device and related apparatuses. Background Art

[0002] Related camera intrinsic parameter calibration methods are mainly designed for a single spectral band. If the camera needs to work in multiple bands, it needs to be calibrated separately for each band, resulting in a long camera intrinsic parameter calibration time and high calibration cost. Summary of the Invention

[0003] The purpose of this application is to provide a camera intrinsic parameter calibration method, a camera calibration method, a tracking device and related devices, so as to save the camera intrinsic parameter calibration time and reduce the calibration cost.

[0004] The purpose of this application is achieved by the following technical solutions:

[0005] In a first aspect, an embodiment of the present application provides a camera intrinsic parameter calibration method, the method comprising: calibrating a parameter value of at least one intrinsic parameter of a target camera in a first wavelength band; for at least part of the intrinsic parameter, based on the parameter value of the intrinsic parameter in the first wavelength band and a specified correspondence between the intrinsic parameter in the first wavelength band and the second wavelength band, determining the parameter value of the intrinsic parameter in a second wavelength band; wherein the first wavelength band and the second wavelength band are non-overlapping wavelength bands of light.

[0006] In some embodiments, the at least one internal parameter includes a distortion parameter, an optical center coordinate, and a focal length, and at least part of the internal parameters includes the focal length. The specified correspondence of the focal length is a corresponding formula, and the corresponding formula includes a focal length ratio coefficient.

[0007] In some embodiments, the method further includes: determining the parameter value of the internal parameter in the uncalibrated band based on the parameter value of the internal parameter in the calibrated band and the specified correspondence between the internal parameter in the calibrated band and the uncalibrated band; wherein the calibrated band is the first band or the second band.

[0008] In some embodiments, the specified correspondence between the intrinsic parameter of the calibration camera and the second band is the same as that of the target camera, and a first calibration light-emitting device and a second calibration light-emitting device are arranged around the calibration camera. The calibration process of the specified correspondence between the intrinsic parameter in the first band and the second band includes: controlling the first calibration light-emitting device to emit light in the first band to calibrate the calibration parameter value of the intrinsic parameter of the calibration camera in the first band; controlling the second calibration light-emitting device to emit light in the second band to calibrate the calibration parameter value of the intrinsic parameter of the calibration camera in the second band; based on the calibration parameter value of the intrinsic parameter in the first band and the calibration parameter value of the internal parameter in the second band, determining the specified correspondence between the intrinsic parameter in the first band and the second band.

[0009] In some embodiments, the light in the first wavelength band is invisible light, and the light in the second wavelength band is visible light.

[0010] In some embodiments, the first wavelength band is an infrared wavelength band, and the second wavelength band is a blue light wavelength band.

[0011] In a second aspect, an embodiment of the present application provides a camera calibration method, the method being used to calibrate a specified correspondence between an internal parameter in any of the above-mentioned camera intrinsic parameter calibration methods and a first band and a second band; the method being applied to a camera calibration device, the camera calibration device comprising: a calibration camera, the specified correspondence between its internal parameter and the first band and the second band being the same as that of a target camera; a first calibration light-emitting device, configured to emit light in the first band; and a second calibration light-emitting device, configured to emit light in the second band; the method comprising: controlling the first calibration light-emitting device to emit light in the first band to calibrate a calibration parameter value of the intrinsic parameter of the calibration camera in the first band; controlling the second calibration light-emitting device to emit light in the second band to calibrate a calibration parameter value of the intrinsic parameter of the calibration camera in the second band; and determining the specified correspondence between the intrinsic parameter in the first band and the second band based on the calibration parameter value of the intrinsic parameter in the first band and the calibration parameter value of the intrinsic parameter in the second band.

[0012] In a third aspect, an embodiment of the present application provides a camera calibration device, which is used to calibrate a specified correspondence between an internal parameter in any of the above-mentioned camera intrinsic parameter calibration methods, between a first band and a second band; the camera calibration device includes: a calibration camera, whose internal parameter has the same specified correspondence between the first band and the second band as that of a target camera; a first calibration light-emitting device, used to emit light in the first band; a second calibration light-emitting device, used to emit light in the second band; a controller, used to control the first calibration light-emitting device to emit light in the first band to calibrate the calibration parameter value of the intrinsic parameter of the calibration camera in the first band; control the second calibration light-emitting device to emit light in the second band to calibrate the calibration parameter value of the intrinsic parameter of the calibration camera in the second band; based on the calibration parameter value of the intrinsic parameter in the first band and the calibration parameter value of the intrinsic parameter in the second band, determine the specified correspondence between the intrinsic parameter in the first band and the second band.

[0013] In a fourth aspect, an embodiment of the present application provides a tracking device, which includes a target camera, a first light-emitting device and a second light-emitting device, wherein the first light-emitting device is used to emit light in a first band, and the second light-emitting device is used to emit light in a second band. The parameter value of at least one intrinsic parameter of the target camera in the first band and the second band is calibrated using any of the above-mentioned camera intrinsic parameter calibration methods.

[0014] In some embodiments, the first light emitting device comprises an infrared LED and the second light emitting device comprises a blue laser.

[0015] In a fifth aspect, an embodiment of the present application provides a scanning device, which includes a target camera, a first light-emitting device and a second light-emitting device, wherein the first light-emitting device is used to emit light in a first band, and the second light-emitting device is used to emit light in a second band. The parameter value of at least one intrinsic parameter of the target camera in the first band and the second band is calibrated using any of the above-mentioned camera intrinsic parameter calibration methods.

[0016] In some embodiments, the first light emitting device comprises an infrared LED and the second light emitting device comprises a blue laser.

[0017] In a sixth aspect, an embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, it implements any of the above-mentioned camera intrinsic parameter calibration methods.

[0018] In a seventh aspect, an embodiment of the present application provides a computer device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements any of the above-mentioned camera intrinsic parameter calibration methods when executing the computer program.

[0019] In an eighth aspect, an embodiment of the present application provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, implements any of the above-mentioned camera intrinsic parameter calibration methods.

[0020] The embodiment of the present application provides a camera intrinsic parameter calibration method, a camera calibration method, a tracking device and related devices, wherein the camera intrinsic parameter calibration method includes: calibrating the parameter value of at least one intrinsic parameter of the target camera in the first band; for at least part of the intrinsic parameter, based on the parameter value of the intrinsic parameter in the first band and the specified correspondence between the intrinsic parameter in the first band and the second band, determining the parameter value of the intrinsic parameter in the second band; wherein the first band and the second band are non-overlapping bands of light. The embodiment of the present application provides a fast and convenient camera intrinsic parameter calibration solution for a target camera operating in two bands. When the target camera is calibrated for the intrinsic parameters, two sets of camera intrinsic parameters in the two bands can be obtained through a single calibration process (corresponding to one of the two bands), thereby avoiding the need to calibrate the two bands separately. This not only saves the camera intrinsic parameter calibration time and reduces the camera intrinsic parameter calibration cost, but also reduces the computational complexity of the camera intrinsic parameter calibration process and saves computing resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present application is further described below with reference to the accompanying drawings and specific implementation methods.

[0022] Figure 1 This is a flow chart of a camera intrinsic parameter calibration method provided in an embodiment of the present application.

[0023] Figure 2 This is a flowchart of a camera calibration method provided in an embodiment of the present application.

[0024] Figure 3 This is a structural block diagram of a camera calibration device provided in an embodiment of the present application.

[0025] Figure 4 This is a structural block diagram of a tracking device provided in an embodiment of the present application.

[0026] Figure 5 This is a structural block diagram of a scanning device provided in an embodiment of the present application.

[0027] Figure 6 This is a structural block diagram of a computer device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of this application.

[0029] In the description of the embodiments of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly indicate the number of technical features indicated. Therefore, features defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0030] Current scanning devices often need to see both the laser and the marker simultaneously. This requires two light-emitting devices: a fill light to illuminate the marker and a laser. These two light-emitting devices often use the same wavelength (for example, infrared or blue light) to facilitate calibration and filter selection. Specifically, for the same camera in a scanning device, light from different wavelengths corresponds to different camera intrinsic parameters. Therefore, choosing the same wavelength reduces the complexity of camera intrinsic calibration.

[0031] Applying the light-emitting device design of the above-mentioned scanning device to a tracking device may present new challenges. This is because light in the blue light band (referred to as blue light) is visible light, while light in the infrared band (referred to as infrared light) is invisible light. In tracking mode, when the light-emitting device is tracking the scanning head, the person operating the scanning head will be within the field of view of the tracking device. If the light-emitting device on the tracking device emits blue light, it can be perceived by the human eye, which will be very glaring and unsafe for the human eye. If the light-emitting device emits infrared light, it cannot be perceived by the human eye and is more user-friendly. Because blue light has weaker energy attenuation and more concentrated energy, laser imaging is clearer and the scanning quality is better. Therefore, in tracking devices, the laser still needs to be selected from the blue light band, while the fill light can be selected from the infrared band. As an example, a fill light in the infrared band is used when tracking the scanning head, and a blue laser is used when the tracking head directly scans the laser.

[0032] It can be seen that the tracking device may be equipped with light-emitting devices of two bands at the same time. This design scheme requires calibrating two sets of camera intrinsic parameters in two bands when calibrating the camera in the tracking device, for example, the intrinsic parameters in the infrared band and the intrinsic parameters in the blue light band.

[0033] To save time calibrating camera intrinsic parameters, consider first calibrating the intrinsic parameters for one band. Then, use the intrinsic parameters for other bands based on the calibrated intrinsic parameters. For cameras, the refractive index of light varies across different bands, but the laws of physics are stable. Therefore, based on the correspondence between the intrinsic parameters for different bands, the intrinsic parameters for other bands can be calibrated based on the intrinsic parameters for the calibrated band.

[0034] The above embodiment uses the infrared band and the blue light band as examples of the first band and the second band for illustration. However, the technical solutions in the embodiments of the present application are applicable not only to the above two bands, but also to camera calibration processes in other bands, and the embodiments of the present application are not limited to this. The above embodiment uses the camera intrinsic parameter calibration process in a tracking device as an example for illustration. However, the technical solutions in the embodiments of the present application are applicable not only to the camera intrinsic parameter calibration process in a tracking device, but also to the camera intrinsic parameter calibration process in a scanning device, and the embodiments of the present application are not limited to this.

[0035] See also Figure 1 , Figure 1 This is a flow chart of a camera intrinsic parameter calibration method provided in an embodiment of the present application.

[0036] To address the problem that cameras operating in multiple bands (two or more) need to calibrate two sets of intrinsic parameters during calibration, it is considered to first calibrate the parameter values ​​of the camera intrinsic parameters in the first band, and then obtain the parameter values ​​of the camera intrinsic parameters in the second band based on the specified correspondence between the intrinsic parameters in different bands.

[0037] like Figure 1 As shown, an embodiment of the present application provides a camera intrinsic parameter calibration method, which includes steps S101 to S102.

[0038] Step S101: calibrating a parameter value of at least one intrinsic parameter of a target camera in a first wavelength band.

[0039] Step S102: for at least part of the internal parameters, based on the parameter values ​​of the internal parameters in the first band and the specified correspondence between the internal parameters in the first band and the second band, determine the parameter values ​​of the internal parameters in the second band.

[0040] The first wavelength band and the second wavelength band are non-overlapping wavelength bands of light.

[0041] The above embodiments do not limit the use scenarios of the target camera. In some embodiments, the target camera is used in a tracking device or a scanning device. To provide light in the first and second wavelength bands, in some embodiments, the tracking device or the scanning device may further include a first light-emitting device and a second light-emitting device, wherein the first light-emitting device is configured to emit light in the first wavelength band and the second light-emitting device is configured to emit light in the second wavelength band. The above embodiments do not limit the use scenarios of the camera intrinsic parameter calibration method, and examples thereof include factory calibration and post-use recalibration.

[0042] In the above embodiment, the first wavelength band and the second wavelength band may be non-overlapping wavelength bands in the spectrum (eg, infrared wavelength band and blue wavelength band). For example, the first wavelength band may be 760nm-1mm, and the second wavelength band may be 380nm-500nm.

[0043] The above embodiments do not limit the light corresponding to the first wavelength band and the second wavelength band. In some embodiments, the light in the first wavelength band may be invisible light, and the light in the second wavelength band may be visible light. In other embodiments, the light in the first wavelength band may be visible light, and the light in the second wavelength band may be invisible light.

[0044] The above embodiments do not limit the first and second wavelength bands. In some embodiments, the first wavelength band may be an infrared wavelength band, and the second wavelength band may be a blue light wavelength band. Thus, during actual device calibration, only the infrared wavelength band camera intrinsics can be calibrated. Based on these infrared wavelength band camera intrinsics, the blue light wavelength band camera intrinsics can be obtained. The obtained blue light wavelength band camera intrinsics can be used in the subsequent blue light laser reconstruction process. In other embodiments, the first wavelength band may be a blue light wavelength band, and the second wavelength band may be an infrared wavelength band.

[0045] The intrinsic parameters of the target camera may include, for example, the focal length f, optical center coordinates (u0, v0), distortion parameters (for example, radial distortion coefficient, tangential distortion coefficient), etc. of the camera. For the sake of convenience of description, the embodiments of the present application may use "intrinsic parameters" or "camera intrinsic parameters", and the physical meanings of the two can be regarded as the same. At least one internal parameter may include, for example, one or more of the focal length, optical center coordinates, and distortion parameters. At least part of the internal parameters refers to part or all of the internal parameters in at least one internal parameter. The above embodiments do not limit the at least one internal parameter and the camera intrinsic parameters contained in at least part of the internal parameters. In some embodiments, the at least one internal parameter may include distortion parameters, optical center coordinates, and focal length.

[0046] Calibrating the parameter value of at least one intrinsic parameter of a target camera in a first wavelength band, for example, involves controlling a first light-emitting device to emit light in a first wavelength band, causing the target camera to operate in the first wavelength band, and calibrating one or more camera intrinsic parameters of the target camera in the first wavelength band to obtain parameter values ​​for each camera intrinsic parameter in the first wavelength band. Determining the parameter value of the intrinsic parameter in the second wavelength band based on the parameter value of the intrinsic parameter in the first wavelength band and a specified correspondence between the intrinsic parameter in the first wavelength band and the second wavelength band, for example, involves inferring (or predicting) the parameter value of the camera intrinsic parameter in the second wavelength band when a hypothetical second light-emitting device emits light in the second wavelength band based on the parameter value of the same camera intrinsic parameter in the first wavelength band and the specified correspondence between the camera intrinsic parameter in the two wavelength bands. In other words, the parameter value of the camera intrinsic parameter in the first wavelength band is obtained through actual calibration, and the parameter value of the camera intrinsic parameter in the second wavelength band is determined based on the parameter value of the camera intrinsic parameter in the first wavelength band and the specified correspondence between the camera intrinsic parameter in the two wavelength bands, rather than being obtained through an actual calibration process.

[0047] The designated corresponding relationship can be represented by a corresponding formula, a corresponding model, or a corresponding data table, for example, and the above embodiment does not limit this. In some embodiments, the designated corresponding relationship can be represented by one or more of a corresponding formula, a corresponding model, and a corresponding data table. The corresponding model can be, for example, a neural network-based model, for example, a BP (Back Propagation) neural network is used to construct an end-to-end mapping model as a corresponding model, or a convolutional neural network (CNN) is trained to obtain a corresponding model.

[0048] In practical applications, camera intrinsic parameters of interest include, for example, distortion parameters, optical center coordinates, and focal length. Distortion parameters and optical center coordinates can be assumed to be unaffected by the imaging wavelength, but focal length is affected by the imaging wavelength and can be calibrated using the aforementioned calibration method. In some embodiments, at least some of these intrinsic parameters may include focal length.

[0049] To simplify the focal length calibration process, the designated correspondence relationship of the focal length can be expressed using a corresponding formula. In some embodiments, the designated correspondence relationship of the focal length can be a corresponding formula. That is, after obtaining the parameter value of the focal length in the first wavelength band, the parameter value of the focal length in the second wavelength band can be calculated based on the parameter value of the focal length in the first wavelength band and the corresponding formula between the focal lengths in the first wavelength band and the second wavelength band. The advantage of this is that the calculation method is simple, and the parameter value of the focal length in the second wavelength band can be calculated conveniently and quickly.

[0050] In some embodiments, to simplify the expression of the designated correspondence between focal lengths in two wavelength bands, the focal lengths in different wavelength bands may be assumed to be a fixed ratio. In some embodiments, the correspondence formula may include a focal length ratio coefficient. This focal length ratio coefficient may be expressed, for example, as a numerical value or a percentage, which is not limited in the above embodiment. As an example, the focal length ratio coefficient may be expressed as two or three decimal places.

[0051] The above embodiment provides a fast and convenient camera intrinsic calibration solution for a target camera operating in two wavelength bands. When performing intrinsic calibration on a target camera, the above embodiment can obtain two sets of camera intrinsic parameters for both bands through a single calibration process (corresponding to one of the two wavelength bands), eliminating the need to calibrate each band separately. This not only saves time and cost for camera intrinsic calibration, but also reduces the computational complexity and resources of the calibration process.

[0052] If the target camera operates in two bands (e.g., infrared and blue), the method in steps S101-S102 can be used to calibrate the camera intrinsic parameters in the first and second bands. If the target camera needs to operate in more bands, any band with calibrated or determined parameter values ​​(e.g., infrared or blue) can be used as a calibrated band, and other bands with neither calibrated nor determined parameter values ​​(e.g., green) can be used as uncalibrated bands. Steps similar to step S102 can be performed again to determine the camera intrinsic parameter values ​​in other bands.

[0053] In some embodiments, the method may further include: determining the parameter value of the intrinsic parameter in the uncalibrated band based on the parameter value of the intrinsic parameter in the calibrated band and the specified correspondence between the intrinsic parameter in the calibrated band and the uncalibrated band; wherein the calibrated band is the first band or the second band. In other words, after obtaining the parameter value of the camera intrinsic parameter in the second band, the parameter values ​​of other uncalibrated bands can be obtained by adapting the parameter value of the camera intrinsic parameter in the first band or the second band, rather than only by adapting the parameter value of the camera intrinsic parameter in the first band. In this way, the amount of data required to obtain and store the specified correspondence can be reduced, and the camera intrinsic parameters in multiple bands can be quickly obtained through a single camera intrinsic parameter calibration step. As an example, assume the target camera needs to operate in five bands (for example, Band A to Band E). Instead of acquiring and storing the specified correspondences between any two bands (a total of 10), it is sufficient to acquire at least four specified correspondences, for example, the specified correspondences between Band A and Band B, Band A and Band C, Band A and Band D, and Band A and Band E. In practical applications, Band A can be used as the first band. The camera intrinsic parameters in Band A can then be calibrated, and the camera intrinsic parameters in Band B, Band C, Band D, and Band E can then be determined separately.

[0054] For example, in a specific application scenario, assuming the target camera needs to operate in both infrared and blue light bands, the camera's intrinsic parameters are first calibrated for the infrared band. Then, based on the infrared band's intrinsic parameters and the specified correspondence between the infrared band and the blue light band, the camera's intrinsic parameters are determined for the blue light band.

[0055] In another specific application scenario, assume that the target camera needs to operate in the infrared band, the blue light band, and the green light band. First, the parameter values ​​of the camera intrinsic parameters in the infrared band are calibrated. Then, based on the parameter values ​​of the camera intrinsic parameters in the infrared band and the specified correspondence between the camera intrinsic parameters in the infrared band and the blue light band, the parameter values ​​of the camera intrinsic parameters in the blue light band are determined. Next, based on the parameter values ​​of the camera intrinsic parameters in the infrared band and the specified correspondence between the camera intrinsic parameters in the infrared band and the green light band, the parameter values ​​of the camera intrinsic parameters in the green light band are determined; alternatively, based on the parameter values ​​of the camera intrinsic parameters in the blue light band and the specified correspondence between the camera intrinsic parameters in the blue light band and the green light band, the parameter values ​​of the camera intrinsic parameters in the green light band are determined.

[0056] The above embodiment provides a camera intrinsic parameter calibration scheme for a single target camera used in multiple bands (which can be regarded as a mixed band, for example, including two or more bands). First, the parameter value of the camera intrinsic parameter in the first band is calibrated, and then the parameter value of the camera intrinsic parameter in the second band is determined based on the parameter value of the camera intrinsic parameter in the first band and the specified correspondence between the camera intrinsic parameter in the first band and the second band. This can save the calibration time of the camera intrinsic parameter in the second band and achieve the purpose of calibrating only once (calibrating the camera intrinsic parameter in the first band) and automatically adapting to obtain the camera intrinsic parameter in the second band. If the camera intrinsic parameter in other bands needs to be calibrated, the parameter value of the camera intrinsic parameter in the uncalibrated band is determined based on the parameter value of the camera intrinsic parameter in the calibrated band and the specified correspondence between the camera intrinsic parameter in the calibrated band and the uncalibrated band.

[0057] The above embodiment provides a fast and convenient camera intrinsic calibration solution for target cameras operating in multiple bands. When performing intrinsic calibration on a target camera, the above embodiment can obtain multiple sets of camera intrinsic parameters for each band through a single calibration process (corresponding to one of the multiple bands), eliminating the need to calibrate each band separately. This not only saves time and reduces the cost of camera intrinsic calibration, but also reduces the computational complexity and resources involved in the calibration process.

[0058] In order to calibrate the designated correspondence between camera intrinsic parameters in different wavelength bands, a calibration camera can be set in the camera calibration device, and the designated correspondence between the intrinsic parameters in the first wavelength band and the second wavelength band can be the same as that of the target camera. In addition, a first calibration light-emitting device and a second calibration light-emitting device for emitting light in the first wavelength band and the second wavelength band can be set around the calibration camera. The designated correspondence is obtained by calibrating the designated correspondence of the calibration camera. In other words, the calibration camera and the target camera do not necessarily have exactly the same intrinsic parameters, but only need to meet the same wavelength band correspondence. For example, if the calibration camera and the target camera use the same lens model, and the lens focus specifications, lens aperture and image sensor assembly processes of the calibration camera and the target camera match, then it is determined that the intrinsic parameter laws of the calibration camera and the target camera for light in different wavelength bands are also consistent. For example, the specified correspondence between the focal lengths of the calibration camera and the target camera with the same internal parameter rules mentioned above in the red light band and the blue light band are both expressed by corresponding formulas, and the focal length ratio coefficient in the corresponding formula is K. Then, K can be determined through the calibration process of the calibration camera with the specified correspondence, and applied to the intrinsic parameter calibration process of the target camera.

[0059] In some embodiments, the specified correspondence between the internal parameter of the calibration camera and the second band is the same as that of the target camera. A first calibration light-emitting device and a second calibration light-emitting device may be arranged around the calibration camera. The calibration process of the specified correspondence between the internal parameter in the first band and the second band may include: controlling the first calibration light-emitting device to emit light in the first band to calibrate the calibration parameter value of the internal parameter of the calibration camera in the first band; controlling the second calibration light-emitting device to emit light in the second band to calibrate the calibration parameter value of the internal parameter of the calibration camera in the second band; and determining the specified correspondence between the internal parameter in the first band and the second band based on the calibration parameter value of the internal parameter in the first band and the calibration parameter value of the internal parameter in the second band.

[0060] The above embodiment can calibrate the camera's intrinsic parameters in the first and second bands, thereby determining a specific correspondence between the camera intrinsic parameters in these two bands. Besides the first and second bands, the specific correspondence between any two bands can be determined by referring to the above calibration process and will not be further described here.

[0061] See also Figure 2 , Figure 2 This is a flowchart of a camera calibration method provided in an embodiment of the present application.

[0062] The present application also provides a camera calibration method for calibrating a specified correspondence between a first wavelength band and a second wavelength band of an intrinsic parameter in any of the aforementioned camera intrinsic parameter calibration methods. The method is applied to a camera calibration device, comprising a calibration camera, a first calibration light-emitting device, and a second calibration light-emitting device. The specified correspondence between the first wavelength band and the second wavelength band of the intrinsic parameters of the calibration camera is the same as that of the target camera. The first calibration light-emitting device is configured to emit light in the first wavelength band. The second calibration light-emitting device is configured to emit light in the second wavelength band. The method includes steps S201 to S203.

[0063] Step S201: controlling the first calibration light-emitting device to emit light in the first wavelength band to calibrate a calibration parameter value of the intrinsic parameter of the calibration camera in the first wavelength band.

[0064] Step S202: controlling the second calibration light-emitting device to emit light in the second wavelength band, so as to calibrate a calibration parameter value of the intrinsic parameter of the calibration camera in the second wavelength band.

[0065] Step S203: determining a designated correspondence between the internal parameter in the first band and the second band based on the calibration parameter value of the internal parameter in the first band and the calibration parameter value of the internal parameter in the second band.

[0066] See also Figure 3 , Figure 3 This is a structural block diagram of a camera calibration device provided in an embodiment of the present application.

[0067] Embodiments of the present application also provide a camera calibration device, configured to calibrate a specified correspondence between a first wavelength band and a second wavelength band for an intrinsic parameter in any of the aforementioned camera intrinsic parameter calibration methods. The camera calibration device includes a calibration camera, a first calibration light-emitting device, a second calibration light-emitting device, and a controller. The specified correspondence between the first wavelength band and the second wavelength band for the calibration camera is the same as that for the target camera. The first calibration light-emitting device is configured to emit light in the first wavelength band. The second calibration light-emitting device is configured to emit light in the second wavelength band. The controller is configured to control the first calibration light-emitting device to emit light in the first wavelength band to calibrate a calibration parameter value of the intrinsic parameter of the calibration camera in the first wavelength band; control the second calibration light-emitting device to emit light in the second wavelength band to calibrate a calibration parameter value of the intrinsic parameter of the calibration camera in the second wavelength band; and determine the specified correspondence between the intrinsic parameter in the first wavelength band and the second wavelength band based on the calibration parameter value of the intrinsic parameter in the first wavelength band and the calibration parameter value of the intrinsic parameter in the second wavelength band.

[0068] See also Figure 4 , Figure 4 This is a structural block diagram of a tracking device provided in an embodiment of the present application.

[0069] An embodiment of the present application also provides a tracking device, which includes a target camera, a first light-emitting device and a second light-emitting device, wherein the first light-emitting device is used to emit light in a first band, and the second light-emitting device is used to emit light in a second band. The parameter value of at least one intrinsic parameter of the target camera in the first band and the second band is calibrated using any of the above-mentioned camera intrinsic parameter calibration methods.

[0070] In some embodiments, the first light emitting device and the second light emitting device may be integrated. In other embodiments, the first light emitting device and the second light emitting device may be independently provided.

[0071] The above embodiments do not limit the first light-emitting device and the second light-emitting device. The first light-emitting device only needs to be able to emit light in the first wavelength band, and the second light-emitting device only needs to be able to emit light in the second wavelength band. As an example, the first light-emitting device can emit light in the first wavelength band, and the second light-emitting device can emit light in the second wavelength band. As another example, the first light-emitting device can emit light in the first wavelength band and the second wavelength band, and the second light-emitting device can emit light in the first wavelength band and the second wavelength band. As another example, the first light-emitting device can emit light in the first wavelength band and the second wavelength band, and the second light-emitting device can emit light in the first wavelength band or the second wavelength band. Therefore, the appropriate first light-emitting device and second light-emitting device can be flexibly selected according to the performance and cost requirements in actual applications. When the first light-emitting device and the second light-emitting device have the same configuration, they can be used interchangeably to reduce maintenance costs.

[0072] To reduce hardware complexity, in some embodiments, the first light-emitting device may include an infrared LED, and the second light-emitting device may include a blue laser. There may be one or more infrared LEDs, and one or more blue lasers. Thus, the LEDs on the tracking device can be infrared LEDs, and the lasers on the tracking device can be blue lasers. This allows the aforementioned camera intrinsic calibration function to be implemented using some existing hardware configurations, reducing equipment modification costs.

[0073] See also Figure 5 , Figure 5 This is a structural block diagram of a scanning device provided in an embodiment of the present application.

[0074] An embodiment of the present application also provides a scanning device, which includes a target camera, a first light-emitting device and a second light-emitting device, wherein the first light-emitting device is used to emit light in a first band, and the second light-emitting device is used to emit light in a second band. The parameter value of at least one intrinsic parameter of the target camera in the first band and the second band is calibrated using any of the above-mentioned camera intrinsic parameter calibration methods.

[0075] In some embodiments, the first light emitting device may include an infrared LED, and the second light emitting device may include a blue laser.

[0076] See also Figure 6 , Figure 6 This is a structural block diagram of a computer device provided in an embodiment of the present application.

[0077] An embodiment of the present application further provides a computer device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements any of the above methods when executing the computer program.

[0078] The computer device may include: a memory 110, a processor 120, and a communication interface 130. The memory 110, the processor 120, and the communication interface 130 are connected via an internal connection path.

[0079] The memory 110 is used to store computer programs. In some implementations, the computer programs may include codes for implementing the methods of the embodiments of the present application.

[0080] The processor 120 is configured to execute the computer program stored in the memory 110 to control the communication interface 130 to receive input data and information and output data such as operation results. In some implementations, when the solutions of the embodiments of the present application are implemented through software or firmware, the computer program for implementing the solutions of the embodiments of the present application may be stored in the processor 120 and executed by the processor 120.

[0081] The memory 110 may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (Programmable ROM, PROM), an erasable programmable read-only memory (Erasable PROM, EPROM), an electrically erasable programmable read-only memory (EEPROM) or a flash memory. The volatile memory may be a random access memory (RAM). It should be noted that the memory 110 described herein is intended to include, but is not limited to, any memory of these and other suitable types. As an example, the memory 110 includes a random access memory (RAM), a cache memory and a read-only memory (ROM). Among them, the memory 110 stores a computer program, and the computer program can be executed by the processor 120 so that the processor 120 implements the steps of any of the above methods.

[0082] The processor 120 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. A general-purpose processor may be a microprocessor, or the processor 120 may be any conventional processor.

[0083] During implementation, each step of the above method can be completed by an integrated logic circuit of the hardware in the processor 120 or by instructions in the form of software. The method disclosed in conjunction with the embodiments of the present application can be directly embodied as being executed by a hardware processor, or can be executed by a combination of hardware and software modules in the processor 120. The software module can be located in a mature storage medium in the art, such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, or an electrically erasable programmable memory, a register, etc. The storage medium is located in the memory 110, and the processor 120 reads the information in the memory 110 and completes the steps of the above method in combination with its hardware. To avoid repetition, it will not be described in detail here.

[0084] In some implementations, in addition to the hardware units described above, the computer device may also include software modules, where the software modules may be, for example, an operating system, a basic input and output system (BIOS), application software, etc.

[0085] An operating system manages one or more of a computer's hardware and software resources, serving as its core and cornerstone. It handles fundamental tasks such as managing and allocating memory, prioritizing resource supply and demand, controlling input and output devices, operating the network, and managing the file system. To facilitate user interaction, most operating systems provide an interface for users to interact with the system.

[0086] The BIOS is used to run hardware initialization during the power-on boot phase and provide runtime services for the operating system and applications. In some implementations, the BIOS can also monitor and display the processor temperature and execute functions such as adjusting temperature protection strategies.

[0087] Application software, also known as application program, can be understood as software written for a specific application purpose of the user. It is one of the main categories of computer software.

[0088] An embodiment of the present application further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, any of the above methods is implemented.

[0089] An embodiment of the present application further provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, implements any of the above methods.

[0090] The computer program product may be a portable compact disc read-only memory (CD-ROM) and include program code, and may be run on a terminal device, such as a personal computer. However, the computer program product of the present application is not limited thereto, and the computer program product may be any combination of one or more computer-readable media.

[0091] It should be understood that the specific examples in this application are only intended to help those skilled in the art better understand the implementation methods of this application, rather than to limit the scope of protection of this application.

[0092] It can be understood that in various implementations of the present application, the size of the serial number of each process does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the present application.

[0093] It can be understood that the various embodiments described in this application can be implemented individually or in combination, and this application is not limited to this.

[0094] Unless otherwise indicated, all technical and scientific terms used in this application have the same meaning as those generally understood by those skilled in the art in the technical field of this application. The terms used in this application are only for the purpose of describing specific embodiments and are not intended to limit the scope of this application. The term "one or more" used in this application includes any and all combinations of one or more related listed items. The singular forms "a", "above", and "the" used in this application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0095] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0096] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described embodiments may refer to the corresponding processes in other embodiments and will not be repeated here.

[0097] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0098] Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected according to actual needs to achieve the objectives of the technical solutions of this application.

[0099] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0100] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a number of instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0101] The above are only specific embodiments of the present application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A camera intrinsic parameter calibration method, characterized in that: The method comprises: Calibrate a parameter value of at least one intrinsic parameter of the target camera in the first band; For at least part of the internal parameters, determining a parameter value of the internal parameter in the second band based on the parameter value of the internal parameter in the first band and a specified correspondence between the internal parameter in the first band and the second band; The first wavelength band and the second wavelength band are non-overlapping wavelength bands of light.

2. The camera intrinsic parameter calibration method according to claim 1, characterized in that: The at least one internal parameter includes a distortion parameter, an optical center coordinate, and a focal length. At least part of the internal parameters includes the focal length. The specified corresponding relationship of the focal length is a corresponding formula, and the corresponding formula includes a focal length ratio coefficient.

3. The camera intrinsic parameter calibration method according to claim 1, characterized in that: The method further comprises: Determining the parameter value of the internal parameter in the uncalibrated band based on the parameter value of the internal parameter in the calibrated band and the specified corresponding relationship between the internal parameter in the calibrated band and the uncalibrated band; The calibrated band is the first band or the second band.

4. The camera intrinsic parameter calibration method according to any one of claims 1 to 3, characterized in that: The designated correspondence between the first band and the second band of the internal parameter of the calibration camera is the same as that of the target camera. A first calibration light-emitting device and a second calibration light-emitting device are arranged around the calibration camera. The calibration process of the designated correspondence between the first band and the second band of the internal parameter includes: Controlling the first calibration light-emitting device to emit light in the first wavelength band to calibrate a calibration parameter value of the intrinsic parameter of the calibration camera in the first wavelength band; controlling the second calibration light-emitting device to emit light in the second wavelength band to calibrate a calibration parameter value of the intrinsic parameter of the calibration camera in the second wavelength band; Based on the calibration parameter value of the internal parameter in the first band and the calibration parameter value of the internal parameter in the second band, a designated correspondence relationship between the internal parameter in the first band and the second band is determined.

5. The camera intrinsic parameter calibration method according to claim 4, characterized in that: The light in the first wavelength band is invisible light, and the light in the second wavelength band is visible light.

6. The camera intrinsic parameter calibration method according to claim 5, characterized in that: The first waveband is an infrared waveband, and the second waveband is a blue light waveband.

7. A camera calibration method, characterized in that: The method is used to calibrate a specified correspondence between the first band and the second band in the method according to any one of claims 1 to 6; The method is applied to a camera calibration device, which includes: Calibrate the camera so that its intrinsic parameters have the same specified correspondence between the first and second bands as the target camera; a first calibration light-emitting device, configured to emit light in the first wavelength band; a second calibration light-emitting device, configured to emit light in the second wavelength band; The method comprises: Controlling the first calibration light-emitting device to emit light in the first wavelength band to calibrate a calibration parameter value of the intrinsic parameter of the calibration camera in the first wavelength band; controlling the second calibration light-emitting device to emit light in the second wavelength band to calibrate a calibration parameter value of the intrinsic parameter of the calibration camera in the second wavelength band; Based on the calibration parameter value of the internal parameter in the first band and the calibration parameter value of the internal parameter in the second band, a designated correspondence relationship between the internal parameter in the first band and the second band is determined.

8. A camera calibration device, characterized in that: The camera calibration device is used to calibrate a specified correspondence between the internal reference in the method according to any one of claims 1 to 6, between the first band and the second band; The camera calibration device comprises: Calibrate the camera so that its intrinsic parameters have the same specified correspondence between the first and second bands as the target camera; a first calibration light-emitting device, configured to emit light in the first wavelength band; a second calibration light-emitting device, configured to emit light in the second wavelength band; A controller is configured to control the first calibration light-emitting device to emit light in the first wavelength band to calibrate a calibration parameter value of the intrinsic parameter of the calibration camera in the first wavelength band; control the second calibration light-emitting device to emit light in the second wavelength band to calibrate a calibration parameter value of the intrinsic parameter of the calibration camera in the second wavelength band; and determine a specified correspondence between the intrinsic parameter in the first wavelength band and the second wavelength band based on the calibration parameter value of the intrinsic parameter in the first wavelength band and the calibration parameter value of the intrinsic parameter in the second wavelength band.

9. A tracking device, characterized in that The tracking device includes a target camera, a first light-emitting device and a second light-emitting device, wherein the first light-emitting device is used to emit light in a first band, and the second light-emitting device is used to emit light in a second band. The parameter values ​​of at least one internal parameter of the target camera in the first band and the second band are calibrated using the method described in any one of claims 1 to 6.

10. The tracking device according to claim 9, wherein The first light emitting device includes an infrared LED, and the second light emitting device includes a blue laser.

11. A scanning device, characterized in that: The scanning device includes a target camera, a first light-emitting device and a second light-emitting device, wherein the first light-emitting device is used to emit light in a first band, and the second light-emitting device is used to emit light in a second band. The parameter values ​​of at least one internal parameter of the target camera in the first band and the second band are calibrated using the method described in any one of claims 1 to 6.

12. The scanning device according to claim 11, wherein: The first light emitting device includes an infrared LED, and the second light emitting device includes a blue laser.

13. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 6 is implemented.

14. A computer device, characterized in that: The computer device includes a memory and a processor, the memory stores a computer program, and the processor implements the method according to any one of claims 1 to 6 when executing the computer program.

15. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 6 is implemented.

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