A multispectral image registration method and device based on a laser foot point constraint region
By using laser foot point constrained areas in multispectral image registration of drone, the registration error problem caused by few matching points and low accuracy in traditional methods is solved, and image registration and fusion with higher accuracy is achieved.
Patent Information
- Application Number
- CN202211070220.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-09-02
- Publication Date
- 2025-06-27
- Estimated Expiration
- 2042-09-02
AI Technical Summary
In the multi-spectral image registration process of traditional drones, few matching points and low accuracy lead to large registration errors.
A multispectral image registration method based on the laser foot point constraint area is adopted, and a laser foot point is formed through a multi-wavelength laser, and an image is collected using a calibrated multispectral camera, thereby selecting the laser foot point as a marking point to form the laser foot point constraint area as a registration primitive image, calculate the distance information between the laser foot points, obtain the registration reference coordinate system, and calculate the coordinate transformation parameters to realize the registration and fusion of the image.
Improve the accuracy of multi-spectral image registration, reduce registration errors, and ensure the quality of image fusion.
Smart Images
Figure CN115439518B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of image processing, and in particular to a multispectral image registration method based on a laser foot point constraint area and a multispectral image registration device based on a laser foot point constraint area. Background Art
[0002] Images obtained by different sensors or the same sensor at different times often have differences in relative translation, rotation, scaling and even distortion, which is very unfavorable for image fusion processing and will cause the image fusion results to contain more erroneous information or produce larger deformations. The process of eliminating such differences is called image registration.
[0003] In practical work, the relative registration method is often used. Its main idea is to take one image as the standard for registration, which is called the reference image; the other image is called the registration image; and the registration image is registered to the reference image coordinate system. According to the relationship between the images to be registered, Brown divides image registration into four categories: multi-sensor based image registration, template based image registration, multi-angle based image registration, and time series based image registration.
[0004] At present, the registration methods can be divided into grayscale-based methods and feature-based methods according to the image information used in image registration. When two images are not registered, the image processing algorithm will lose the basis for analysis and calculation; if the registration accuracy is high, it can provide better technical support and guarantee for the subsequent processing of the image. Therefore, image registration is very important. Summary of the invention
[0005] In view of the defects and shortcomings in the prior art, the present invention provides a multispectral image registration method and device based on laser foot point constraint area, which solves the problem of large registration error caused by few matching points and low precision in the traditional UAV multispectral image registration process.
[0006] As a first aspect of the present invention, a multispectral image registration method based on a laser foot point constraint area is provided, comprising:
[0007] Step S1: Obtain a calibrated multispectral camera and multi-wavelength laser;
[0008] Step S2: emitting multi-wavelength laser light through the calibrated multi-wavelength laser to form a plurality of laser footprints; and collecting a set of original multi-spectral images including all laser footprints through the calibrated multi-spectral camera;
[0009] Step S3: selecting multiple laser footprints as marking points from the overlapping areas of all original multispectral images, and the multiple marking points constitute a laser footprint constraint area;
[0010] Step S4: Use the laser foot point constraint region as the registration primitive image. Based on the distance information between the laser foot points in the registration primitive image, obtain the registration reference coordinate system, and calculate the coordinate transformation parameters between the coordinates of the registration primitive image and the reference coordinates in the registration reference coordinate system.
[0011] Step S5: According to the coordinate transformation parameters, register all the original multi-spectral images to the registration reference coordinate system, and fuse all the original multi-spectral images registered to the registration reference coordinate system to achieve the registration and fusion of the multi-spectral images.
[0012] Further, the obtaining of the calibrated multi-spectral camera and the multi-wavelength laser includes:
[0013] Integrate the multi-wavelength laser and the multi-spectral camera. Before integration, it is necessary to calibrate the multi-spectral camera. The wavelength of the multi-wavelength laser is selected within the spectral bands of each channel of the multi-spectral camera. The specific steps are as follows:
[0014] Calibrate the spectral bands of each channel of the multi-spectral camera to determine the light source wavelength of the multi-wavelength laser.
[0015] Perform radiometric correction and geometric correction on the images captured by the multi-spectral camera.
[0016] Adjust the multi-wavelength laser to ensure that the formed laser foot points are evenly distributed in the original multi-spectral images of each channel.
[0017] Further, the using the laser foot point constraint region as the registration primitive image includes:
[0018] Use the laser foot points, the connections between the laser foot points, or the planes formed by the connections between the laser foot points in the laser foot point constraint region as the registration primitive image.
[0019] Further, the obtaining of the registration reference coordinate system based on the distance information between the laser foot points in the registration primitive image, where the registration reference coordinate system is the north-east-down coordinate system, includes:
[0020] Utilize the airborne GPS positioning information and the IMU pose information, combined with the distance information between the laser foot points in the registration primitive image, to obtain the north-east-down coordinate system.
[0021] Further, the emitting of multi-wavelength laser by the calibrated multi-wavelength laser to form multiple laser foot points; and the acquisition of a set of original multi-spectral images containing all the laser foot points by the calibrated multi-spectral camera includes:
[0022] The multi-wavelength laser combines laser beams of multiple wavelengths through laser beam combining technology, so that multiple laser beams are combined into one optical path by means of projection and reflection, to ensure that the reflected information of the same laser foot point is collected by each channel of the multi-spectral camera.
[0023] As another aspect of the present invention, there is provided a multi-spectral image registration device based on a laser foot point constraint region for implementing the multi-spectral image registration method based on a laser foot point constraint region described above. The multi-spectral image registration device based on a laser foot point constraint region includes:
[0024] An acquisition module, configured to acquire a calibrated multi-spectral camera and a multi-wavelength laser;
[0025] The calibrated multi-wavelength laser is configured to emit multi-wavelength laser to form multiple laser foot points;
[0026] The calibrated multi-spectral camera is configured to acquire a set of original multi-spectral images including all laser foot points;
[0027] A selection module, configured to select multiple laser foot points as marker points from the overlapping regions of all the original multi-spectral images, and the multiple marker points form a laser foot point constraint region;
[0028] A calculation module, configured to use the laser foot point constraint region as a registration primitive image, obtain a registration reference coordinate system according to the distance information between the laser foot points in the registration primitive image, and calculate the coordinate transformation parameters between the coordinates of the registration primitive image and the reference coordinates in the registration reference coordinate system;
[0029] A registration fusion module, configured to register all the original multi-spectral images to the registration reference coordinate system according to the coordinate transformation parameters, and fuse the original multi-spectral images all registered to the registration reference coordinate system, so as to achieve the registration and fusion of the multi-spectral images.
[0030] Further, the acquisition module is specifically configured to integrate the multi-wavelength laser and the multi-spectral camera. Before integration, the multi-spectral camera needs to be calibrated. Among them, the wavelength of the multi-wavelength laser is selected within the spectral band ranges of each channel of the multi-spectral camera, specifically including:
[0031] Calibrate the spectral bands of each channel of the multi-spectral camera to determine the light source wavelength of the multi-wavelength laser;
[0032] Perform radiometric correction and geometric correction on the images captured by the multi-spectral camera;
[0033] Adjust the multi-wavelength laser to ensure that the formed laser foot points are evenly distributed in the original multi-spectral images of each channel.
[0034] Further, the calculation module is further configured to use the laser foot points, the laser foot point connection lines, or the laser foot point connection line planes in the laser foot point constraint region as the registration primitive images.
[0035] Further, the registration reference coordinate system is a north-east-down coordinate system. By using the airborne GPS positioning information and the IMU pose information, and combining the distance information between the laser foot points in the registration primitive images, the north-east-down coordinate system is obtained.
[0036] Further, the multi-wavelength laser synthesizes laser beams of multiple wavelengths through a laser beam combining technique, so that multiple laser beams are combined into one optical path through projection and reflection methods, to ensure that the reflection information of the same laser foot point is collected by each channel of the multi-spectral camera.
[0037] The multi-spectral image registration method based on the laser foot point constraint region provided by the present invention has the following advantages: In the multi-spectral image registration and fusion process based on the laser foot point constraint region, first, the camera is calibrated to eliminate image distortion caused by factors such as the multi-spectral camera itself and the environment; then, a multi-wavelength laser is used to determine the registration primitive and a suitable registration strategy is used to solve the problem of large registration errors caused by few matching points and low accuracy in the traditional UAV multi-spectral image registration process. Description of the Drawings
[0038] The drawings are used to provide a further understanding of the present invention, and constitute a part of the specification. They are used to explain the present invention together with the following specific embodiments, but do not constitute a limitation to the present invention.
[0039] Figure 1 It is a flowchart of the multi-spectral image registration method based on the laser foot point constraint region provided by the present invention.
[0040] Figure 2 It is a flowchart of the specific implementation manner of the multi-spectral image registration method based on the laser foot point constraint region provided by the present invention.
[0041] Figure 3 It is a schematic diagram of the overlapping region of the multi-spectral image provided by the present invention.
[0042] Figure 4 It is a schematic diagram of the laser foot point constraint region provided by the present invention.
[0043] Figure 5 It is a schematic diagram of the north-east-down NED coordinate system and the camera pixel coordinate system provided by the present invention. Specific Embodiments
[0044] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments may be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.
[0045] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.
[0046] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so as to implement the embodiments of the present invention described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily need to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.
[0047] In this embodiment, a multi-spectral image registration method based on a laser foot point constraint region is provided. Figure 1 It is a flowchart of the multi-spectral image registration method based on the laser foot point constraint region provided by the present invention. As Figure 1 shown, the multi-spectral image registration method based on the laser foot point constraint region includes:
[0048] Step S1: Obtain a calibrated multi-spectral camera and a multi-wavelength laser.
[0049] Step S2: Emitting multi-wavelength laser through the calibrated multi-wavelength laser to form a plurality of laser foot points; and collecting a set of original multi-spectral images including all the laser foot points through the calibrated multi-spectral camera.
[0050] Step S3: Selecting a plurality of laser foot points from the overlapping regions of all the original multi-spectral images as marker points, and the plurality of marker points form a laser foot point constraint region.
[0051] Step S4: Taking the laser foot point constraint region as a registration primitive image, obtaining a registration reference coordinate system according to the distance information between the laser foot points in the registration primitive image, and calculating the coordinate transformation parameters between the coordinates of the registration primitive image and the reference coordinates in the registration reference coordinate system.
[0052] Step S5: According to the coordinate transformation parameters, all the original multi-spectral images are registered to the registration reference coordinate system, and the original multi-spectral images registered to the registration reference coordinate system are fused to achieve the registration and fusion of the multi-spectral images.
[0053] In this embodiment, in addition to the registration strategies in steps S4 and S5, another registration strategy is to define one image as the reference image and other images as the images to be registered, and register all the images to be registered to the coordinate system of the reference image.
[0054] The multi-spectral image registration method based on the laser foot point constraint region provided by the embodiment of the present invention, as Figure 2 shown, mainly includes camera calibration and correction, laser beam combination, laser foot point matching, original multi-spectral image registration and fusion, etc., and can realize the registration and fusion of multi-spectral images in the case of limited feature points and difficult and low-precision extraction of feature points from the original images.
[0055] Preferably, the obtaining of the calibrated multi-spectral camera and multi-wavelength laser includes:
[0056] Integrate the calibrated multi-wavelength laser and the multi-spectral camera. Before integration, the multi-spectral camera needs to be calibrated. Among them, the wavelength of the multi-wavelength laser is selected within the spectral band range of each channel of the multi-spectral camera, and the specific steps are as follows:
[0057] Calibrate the spectral band of each channel of the multi-spectral camera to determine the light source wavelength of the multi-wavelength laser, and calibrate the multi-wavelength laser; in this embodiment, the setting of the multi-wavelength laser utilizes the laser beam combination technology to synthesize multiple laser beams onto one optical path through projection and reflection methods, and integrate multiple single-wavelength lasers.
[0058] Perform radiometric correction and geometric correction on the images captured by the multi-spectral camera to eliminate the distortion of the multi-spectral images;
[0059] Adjust the multi-wavelength laser to ensure that the formed laser foot points are evenly distributed in the original multi-spectral images of each channel. After the calibrated multi-wavelength laser and the multi-spectral camera are integrated, the laser foot points can be clearly collected by each channel of the multi-spectral camera, and the corresponding same ground laser foot points in each spectral image correspond one by one.
[0060] Specifically, calibrate the common field of view of each channel of the multi-spectral camera. In this embodiment, a four-channel multi-spectral camera is taken as an example. All spectral channels of the multi-spectral camera have an overlapping area, that is, the overlapping area of all the original multi-spectral images. Please refer to Figure 3, in the figure, 1, 2, 3, and 4 are four-channel original multispectral images, and 5 is the overlapping area of all original multispectral images; marker points are selected within the common field of view of the multispectral camera (equivalent to the image overlapping area 5) by a multi-wavelength laser. In this embodiment, three marker points are taken as an example. Please refer to Figure 4 , in the image overlapping area 5, the three laser foot point image points 13, 14, and 15 form a constraint area. The corresponding laser foot points in each band spectral image can form a set of feature matching point pairs, the corresponding foot point connection lines can form a set of feature matching line pairs, and the corresponding foot point planes can form a set of feature matching face pairs.
[0061] Specifically, within the laser foot point constraint area, in this embodiment, the foot point feature matching point pairs are used as the registration primitive images. Based on the affine transformation model, the coordinate transformation parameters are calculated using the coordinates of the registration primitive images and the north-east-down coordinates. In this embodiment, the north-east-down NED coordinate system is obtained by using the airborne GPS positioning information and the IMU pose information, combined with the laser foot point distance information, and the north-east-down coordinate system is selected as the registration reference coordinate system. According to the coordinate transformation parameters, all the original multispectral images are registered to the north-east-down coordinate system. The model for projecting the pixel coordinates P(x, y, z) of the original multispectral image to the north-east-down coordinates p(u, v) is as Figure 5 shown, and then the registration and fusion of the multispectral images are realized to obtain the fused image.
[0062] Preferably, taking the laser foot point constraint area as the registration primitive image includes:
[0063] Taking the laser foot points, the laser foot point connection lines, or the laser foot point connection line planes in the laser foot point constraint area as the registration primitive image.
[0064] Preferably, obtaining the registration reference coordinate system according to the distance information between the laser foot points in the registration primitive image, and the registration reference coordinate system being the north-east-down coordinate system, includes:
[0065] Using the airborne GPS positioning information and the IMU pose information, combined with the distance information between the laser foot points in the registration primitive image, to obtain the north-east-down coordinate system.
[0066] Preferably, emitting multi-wavelength lasers through the calibrated multi-wavelength laser to form multiple laser foot points; and collecting a set of original multispectral images including all laser foot points through the calibrated multispectral camera, includes:
[0067] The multi-wavelength laser combines the laser beams of multiple wavelengths through laser beam combination technology, so that multiple laser beams are synthesized into one optical path through projection and reflection methods to ensure that the reflection information of the same laser foot point is collected by each channel of the multispectral camera.
[0068] As another embodiment of the present invention, there is provided a multispectral image registration device based on a laser foot point constraint region for implementing the multispectral image registration method based on the laser foot point constraint region described above. The multispectral image registration device based on the laser foot point constraint region includes:
[0069] An acquisition module for acquiring a calibrated multispectral camera and a multi-wavelength laser;
[0070] The calibrated multi-wavelength laser is used to emit multi-wavelength laser to form a plurality of laser foot points;
[0071] The calibrated multispectral camera is used to collect a set of original multispectral images including all laser foot points;
[0072] A selection module for selecting a plurality of laser foot points as marker points from the overlapping regions of all the original multispectral images, and the plurality of marker points form a laser foot point constraint region;
[0073] A calculation module for using the laser foot point constraint region as a registration primitive image, obtaining a registration reference coordinate system according to the distance information between the laser foot points in the registration primitive image, and calculating the coordinate transformation parameters between the coordinates of the registration primitive image and the reference coordinates in the registration reference coordinate system;
[0074] A registration fusion module for registering all the original multispectral images to the registration reference coordinate system according to the coordinate transformation parameters, and fusing the original multispectral images all registered to the registration reference coordinate system to achieve the registration fusion of the multispectral images.
[0075] Preferably, the acquisition module is specifically configured to integrate the multi-wavelength laser and the multispectral camera. Before integration, the multispectral camera needs to be calibrated. Among them, the wavelength of the multi-wavelength laser is selected within the spectral bands of each channel of the multispectral camera, specifically including:
[0076] Calibrating the spectral bands of each channel of the multispectral camera to determine the light source wavelength of the multi-wavelength laser;
[0077] Performing radiometric correction and geometric correction on the images captured by the multispectral camera;
[0078] Adjusting the multi-wavelength laser to ensure that the formed laser foot points are evenly distributed in the original multispectral images of each channel.
[0079] Preferably, the calculation module is further configured to use the laser foot points, the connections between the laser foot points, or the planes formed by the connections between the laser foot points in the laser foot point constraint region as the registration primitive images. In this embodiment, such as laser foot points, the connections between the foot points, the planes determined by the foot points, or gray level information are used as the registration primitives.
[0080] Preferably, the registration reference coordinate system is the north-east-down coordinate system. By using the airborne GPS positioning information and the IMU pose information, and combining the distance information between the laser foot points in the registration primitive images, the north-east-down coordinate system is obtained.
[0081] Preferably, the multi-wavelength laser uses the laser beam combining technology to combine the laser beams of multiple wavelengths, so that multiple paths of lasers are synthesized into one optical path through projection and reflection methods, to ensure that the reflection information of the same laser foot point is collected by each channel of the multi-spectral camera.
[0082] Preferably, each spectral channel of the multi-spectral camera has a common field of view, which is manifested as an overlapping area in the images collected by each spectral channel simultaneously.
[0083] Preferably, the wavelengths of the multi-wavelength laser are within the wavelength coverage range of the multi-spectral camera, and the number of wavelengths is not less than the number of spectral bands of the multi-spectral camera.
[0084] Preferably, the multi-wavelength laser uses the laser beam combining technology to synthesize multiple paths of lasers into one optical path through projection and reflection methods, and integrates multiple single-wavelength lasers.
[0085] Preferably, the multi-wavelength laser can also be implemented by a single multi-wavelength laser source laser.
[0086] Preferably, the number of laser foot points is not less than 3. All the laser foot points are not collinear and form a foot point constraint region within the common field of view, and the laser foot points are evenly distributed within the common field of view region of each channel of the camera.
[0087] The multi-spectral image registration method based on the laser foot point constraint region provided by the embodiment of the present invention aims at the problem of large registration errors caused by few matching points and low accuracy in the traditional UAV multi-spectral image registration process. A multi-wavelength laser is used to endow high-precision laser foot points within the common field of view (image overlapping region) of each channel of the multi-spectral camera, and the constraint region registration is realized by using the laser foot points. Finally, the original multi-spectral images are registered and fused by using the obtained registration parameters.
[0088] It can be understood that the above embodiments are merely exemplary embodiments adopted to illustrate the principles of the present invention, and the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also regarded as the protection scope of the present invention.
Claims
1. A multi-spectral image registration method based on a laser foot point constraint region, characterized in that, The multi-spectral image registration method based on the laser foot point constraint region includes: Step S1: Obtain a calibrated multi-spectral camera and a multi-wavelength laser; Step S2: Emit multi-wavelength laser through the calibrated multi-wavelength laser to form multiple laser foot points; and collect a set of original multi-spectral images containing all the laser foot points through the calibrated multi-spectral camera; Step S3: Select multiple laser foot points from the overlapping region of all the original multi-spectral images as marker points, and the multiple marker points form the laser foot point constraint region; Step S4: Take the laser foot point constraint region as the registration primitive image, obtain the registration reference coordinate system according to the distance information between the laser foot points in the registration primitive image, and calculate the coordinate transformation parameters between the coordinates of the registration primitive image and the reference coordinates in the registration reference coordinate system; Step S5: According to the coordinate transformation parameters, register all the original multi-spectral images to the registration reference coordinate system, and fuse the original multi-spectral images all registered to the registration reference coordinate system to achieve the registration and fusion of the multi-spectral images.
2. The multispectral image registration method based on the laser foot point constraint region according to claim 1, wherein The obtaining of the calibrated multi-spectral camera and the multi-wavelength laser includes: Integrate the multi-wavelength laser and the multi-spectral camera. Before integration, it is necessary to calibrate the multi-spectral camera. Among them, the wavelength of the multi-wavelength laser is selected within the spectral band range of each channel of the multi-spectral camera. The specific steps are as follows: Calibrate the spectral band of each channel of the multi-spectral camera to determine the light source wavelength of the multi-wavelength laser; Perform radiometric correction and geometric correction on the images captured by the multi-spectral camera; Adjust the multi-wavelength laser to ensure that the formed laser foot points are evenly distributed in the original multi-spectral images of each channel.
3. The multispectral image registration method based on the laser foot point constraint region according to claim 1, wherein The taking the laser foot point constraint region as the registration primitive image includes: Taking the laser foot points, the connections of the laser foot points, or the planes of the connections of the laser foot points in the laser foot point constraint region as the registration primitive image.
4. The multispectral image registration method based on the laser foot point constraint region according to claim 1, wherein The obtaining the registration reference coordinate system according to the distance information between the laser foot points in the registration primitive image, and the registration reference coordinate system is the north-east-down coordinate system, includes: Utilize the airborne GPS positioning information and the IMU pose information, combined with the distance information between the laser foot points in the registration primitive image, to obtain the north-east-down coordinate system.
5. The multispectral image registration method based on the laser foot point constraint region according to claim 1, characterized in that The emitting multi-wavelength laser through the calibrated multi-wavelength laser to form multiple laser foot points; and collecting a set of original multi-spectral images containing all the laser foot points through the calibrated multi-spectral camera includes: The multi-wavelength laser combines multiple laser beams of different wavelengths through laser beam combining technology, so that multiple laser beams are synthesized into one optical path through projection and reflection methods to ensure that the reflection information of the same laser foot point is collected by each channel of the multi-spectral camera.
6. A multispectral image registration device based on a laser foot point constraint region, which is used to implement the multispectral image registration method based on the laser foot point constraint region according to any one of claims 1 to 5, and is characterized in that, The multi-spectral image registration device based on the laser foot point constraint region includes: An acquisition module for acquiring a calibrated multi-spectral camera and a multi-wavelength laser; The calibrated multi-wavelength laser is used to emit multi-wavelength laser to form multiple laser foot points; The calibrated multispectral camera is used to collect a set of original multispectral images containing all laser foot points; A selection module is used to select multiple laser foot points from the overlapping regions of all the original multispectral images as marker points, and the multiple marker points form a laser foot point constraint region; A calculation module is used to use the laser foot point constraint region as a registration primitive image, obtain a registration reference coordinate system according to the distance information between the laser foot points in the registration primitive image, and calculate the coordinate transformation parameters between the coordinates of the registration primitive image and the reference coordinates in the registration reference coordinate system; A registration and fusion module is used to register all the original multispectral images to the registration reference coordinate system according to the coordinate transformation parameters, and fuse the original multispectral images all registered to the registration reference coordinate system to achieve the registration and fusion of the multispectral images.
7. The multi-spectral image registration device based on a laser foot point constraint region according to claim 6, wherein The acquisition module is specifically used to integrate the multi-wavelength laser and the multispectral camera. Before integration, the multispectral camera needs to be calibrated. The wavelength of the multi-wavelength laser is selected within the spectral bands of each channel of the multispectral camera, specifically including: Calibrate the spectral bands of each channel of the multispectral camera to determine the light source wavelength of the multi-wavelength laser; Perform radiometric correction and geometric correction on the images captured by the multispectral camera; Adjust the multi-wavelength laser to ensure that the formed laser foot points are evenly distributed in the original multispectral images of each channel.
8. The multi-spectral image registration device based on a laser foot point constraint region according to claim 6, wherein The calculation module is further used to use the laser foot points, the laser foot point connection lines or the laser foot point connection line planes in the laser foot point constraint region as the registration primitive image.
9. The multispectral image registration device based on the laser foot point constraint region according to claim 6, characterized in that The registration reference coordinate system is the north-east-down coordinate system. The north-east-down coordinate system is obtained by using the airborne GPS positioning information and the IMU pose information and combining the distance information between the laser foot points in the registration primitive image.
10. The multispectral image registration device based on a laser foot point constraint region according to claim 6, wherein The multi-wavelength laser combines multiple laser beams of different wavelengths through laser beam combination technology, so that multiple laser beams are synthesized onto one optical path through projection and reflection methods to ensure that the reflection information of the same laser foot point is collected by each channel of the multispectral camera.
Citation Information
Patent Citations
Building surveying and mapping method combining laser radar with aerial photography
CN103076612A
High-flux greenhouse plant phenotype measurement system based on multispectral point cloud fusion
CN108981569A