Unmanned aerial vehicle aerial survey image control point layout method and system for water conservancy project, and product

Abstract

The invention provides an unmanned aerial vehicle aerial survey image control point layout method for a water conservancy project, and the method comprises the steps: dividing a riverway into a survey region range on a map, segmenting the survey region range in an end-to-end overlapping manner based on the direction of the riverway and the single-sortie aerial photography area of an unmanned aerial vehicle, and obtaining a plurality of rectangular regions; the adjacent rectangular areas overlap the distance of the flight height of at least one unmanned aerial vehicle. The first positions of the image control points are selected at the four corners of the rectangular area in a point group mode, so that the image control points on the four corners of the same group can be commonly used in the adjacent rectangular areas, the number of the arranged image control points is greatly reduced, and the working efficiency is improved.

Description

Technical Field

[0001] The present application relates to the field of aerial photogrammetry technology, and in particular, to a method, system, and product for placing control points for drone aerial surveying of water conservancy projects. Background Art

[0002] With the rapid development of UAV technology, UAV low-altitude photogrammetry technology, as an efficient, flexible and relatively low-cost mapping method, has gradually demonstrated its unique advantages in engineering surveying, topographic mapping, environmental monitoring and other fields. This technology uses the high-resolution camera carried by the UAV to quickly shoot the target area at low altitude, obtain a large amount of ground image data, and then generate high-precision topographic maps, three-dimensional models and other geographic information products through photogrammetry analysis.

[0003] In the workflow of UAV low-altitude photogrammetry, the layout of image control points (GCPs) is a crucial link. GCPs are the basis for analytical aerial triangulation and digital mapping. The selection of their positions and the precise determination of their coordinates directly affect the accuracy and quality of subsequent internal mapping. Traditional GCP layout methods are mainly aimed at measurement areas of regular shapes, such as rectangular or square areas, and GCPs are evenly laid out at the four corners of these areas and at certain intervals within the area. This method ensures measurement accuracy while also being easy to implement and manage.

[0004] However, in practical applications, especially in the measurement of water conservancy projects, the measurement area often presents a complex shape, such as the short-distance serpentine area on both sides of the river. Such areas are not only irregular in shape, but also their narrow and long characteristics make it difficult to directly apply the traditional rectangular area image control point layout method. If the serpentine area is forcibly cut into regular rectangular areas connected end to end for image control point layout, although it is theoretically feasible, it will cause the image control points at the four corners of adjacent partitions at the connection to be too close, resulting in an unnecessary increase in the number of image control points. This not only increases the workload of field measurement and reduces work efficiency, but may also affect the uniformity of the overall measurement accuracy due to the excessive density of image control points. Summary of the invention

[0005] The purpose of this application is to provide a method, system, and product for deploying UAV aerial survey image control points for water conservancy projects to solve the current problem of low efficiency in measuring serpentine areas of rivers.

[0006] In order to achieve the above objectives, this application adopts the following technical solutions:

[0007] A method for arranging control points of unmanned aerial survey images for water conservancy projects, comprising:

[0008] Determine the survey area of ​​the river channel, and divide the survey area into multiple rectangular areas in an overlapping manner based on the direction of the river channel and the area of ​​a single drone aerial survey. The overlapping distance of adjacent rectangular areas in the direction of the river channel is at least the flight height of a drone during aerial survey.

[0009] Determine the layout distance of the image control points in the heading direction and the layout distance in the lateral direction; where:

[0010] The layout distance on the heading is calculated by the length of the baseline of a single picture on the heading and the baseline span of the heading image control point. The calculation formula of the length of the baseline of a single picture on the heading is b x =L x ×(1-P x )×a, where b x Indicates the length of the heading single picture baseline, L x Indicates the heading amplitude or pixel of the digital image, P x It represents the heading overlap of digital images, and a represents the pixel size of the camera carried by the drone;

[0011] The lateral layout distance is calculated by the lateral single image baseline length and the lateral image control point baseline span. The calculation formula of the lateral single image baseline length is: y =L y ×(1-P y )×a, where b y Indicates the baseline length of a single lateral image, L y Indicates the lateral amplitude or pixel of a digital image, P y Indicates the lateral overlap of digital images;

[0012] According to the layout distance of the image control points in the heading direction and the layout distance in the lateral direction, the layout positions of the image control points within the measurement area are determined in each of the rectangular areas.

[0013] In some implementations, determining the layout positions of image control points within the measurement area includes: selecting first positions of image control points in the form of point groups at four corners of each of the rectangular areas, and each point group includes at least three points.

[0014] In some embodiments, determining the layout position of the image control points within the measurement area further includes: determining the second position of the image control points based on the first position and the layout distance of the image control points in the heading direction and the layout distance in the lateral direction.

[0015] In some embodiments, when determining the layout positions of image control points within the survey area, when the map scale is 1:2000, the heading image control point baseline span is 6, and the layout distance of the image control points in the heading direction is 6 times the length of the single picture baseline in the heading direction; when the map scale is 1:1000, the heading image control point baseline span is 4, and the layout distance of the image control points in the heading direction is 4 times the length of the single picture baseline in the heading direction; when the map scale is 1:500, the heading image control point baseline span is 3, and the layout distance of the image control points in the heading direction is 3 times the length of the single picture baseline in the heading direction; the lateral route span is 3 at different map scales, and the layout distance of the image control points in the lateral direction is 3 times the length of the single picture baseline in the lateral direction.

[0016] In some embodiments, the formula Determine the altitude of the drone during aerial survey, where GSD represents the ground resolution of the lowest point in the rectangular area, a represents the pixel size of the camera carried by the drone, f represents the focal length of the camera, and H represents the altitude of the drone during aerial survey.

[0017] In some embodiments, the type of the drone and the type of the camera it carries are selected according to the following method: if the number of river bends within the survey area is less than or equal to a first preset value, the drone is a fixed-wing or compound-wing drone and is equipped with a full-frame camera; if the number of river bends within the survey area is greater than the first preset value, the drone is a fixed-wing or compound-wing drone and is equipped with a full-frame camera; or, if the area of ​​the rectangular area is greater than a second preset value, the drone is a fixed-wing or compound-wing drone and is equipped with a full-frame camera; if the area of ​​the rectangular area is less than or equal to the second preset value, the drone is a fixed-wing or compound-wing drone and is equipped with a full-frame camera.

[0018] In some embodiments, when determining the altitude of the drone during aerial survey, when the map scale is 1:2000, the ground resolution of the lowest point in the rectangular area is less than or equal to 16 cm; when the map scale is 1:1000, the ground resolution of the lowest point in the rectangular area is less than or equal to 8 cm; when the map scale is 1:500, the ground resolution of the lowest point in the rectangular area is less than or equal to 5 cm.

[0019] According to a second aspect of the present application, there is provided a UAV aerial survey image control point layout system for water conservancy projects, comprising a survey area segmentation module, an image control point distance calculation module and an image control point selection module; the survey area segmentation module is used to determine the survey area range of a river channel, and based on the direction of the river channel and the area of ​​a single drone aerial photography, the survey area range is divided in an end-to-end overlapping manner to obtain a plurality of rectangular areas, and the overlapping distance between adjacent rectangular areas in the direction of the river channel is at least the flight altitude of a UAV during aerial survey; the image control point distance calculation module is used to determine the layout distance of the image control points in the heading direction and the layout distance in the lateral direction; the image control point selection module is used to determine the layout position of the image control points in the survey area in each of the rectangular areas according to the layout distance of the image control points in the heading direction and the layout distance in the lateral direction.

[0020] A third aspect of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program. When the computer program runs on a processor, the processor executes the identification method as described in the first aspect.

[0021] The fourth aspect of the present application provides an electronic device, comprising: at least one memory for storing programs; at least one processor for executing the programs stored in the memory, when the program stored in the memory is executed, the processor is used to execute the identification method described in the first aspect.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] The present application provides a method for laying out image control points for drone aerial survey of water conservancy projects, which divides the river into survey areas on a map, and divides the survey area into multiple rectangular areas in an overlapping manner based on the river direction and the area of ​​a single drone aerial photograph. The first position of the image control point is selected in the form of a point group at the four corners of the rectangular area, so that the image control points on the same group of four corners can be used together in adjacent rectangular areas, which greatly reduces the number of image control points to be laid out and improves work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 A schematic diagram showing a flow chart of a method for placing control points for drone aerial surveying of a water conservancy project according to an embodiment of the present application;

[0026] Figure 2 A schematic diagram of the structure of a UAV aerial survey image control point placement system for water conservancy projects according to an embodiment of the present application is shown;

[0027] Figure 3 A schematic diagram of the structure of a drone aerial survey image control point placement system for water conservancy projects according to another embodiment of the present application is shown;

[0028] Figure 4 A schematic diagram of the structure of an electronic terminal in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0029] The technical solutions of the specific implementation methods of the present application are further described in detail below in conjunction with the accompanying drawings. These implementation methods are only used to illustrate the present application, but not to limit the present application.

[0030] The term "and / or" in this application is a description of the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B can represent the existence of A alone, the existence of A and B at the same time, and the existence of B alone. In the present invention, the symbol " / " indicates that the associated objects are in an "or" relationship, for example, "A / B" means "A or B".

[0031] The terms "first" and "second" in the specification and claims of this application are used to distinguish different objects rather than to describe a specific order of the objects. For example, "first response message" and "second response message" are used to distinguish different response messages rather than to describe a specific order of the response messages.

[0032] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be considered as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0033] In the description of the embodiments of the present application, unless otherwise specified, "multiple" means two or more than two. For example, multiple processing units refer to two or more processing units, etc., and multiple elements refer to two or more elements, etc.

[0034] The following is a detailed description of a method, system and product for deploying control points for drone aerial surveying of water conservancy projects in conjunction with the accompanying drawings.

[0035] Figure 1 The following is a flow chart showing a method for placing control points for drone aerial surveying of water conservancy projects according to an embodiment of the present application. Figure 1As shown, the method for setting control points for drone aerial surveying of water conservancy projects in this embodiment includes the following steps:

[0036] Step S110, determine the survey area of ​​the river channel, and based on the direction of the river channel and the area of ​​a single drone aerial photography, divide the survey area into multiple rectangular areas in an overlapping manner to obtain a plurality of rectangular areas. The rectangular areas are the parts close to straight lines within the survey area, and the overlapping distance of adjacent rectangular areas in the flow direction of the river channel is at least the flight altitude of a drone during aerial survey.

[0037] The calculation of the above-mentioned altitude is to determine the ground resolution GSD based on the map scale, the camera pixel size a and the focal length f to determine the altitude H. The calculation formula (1) of the altitude H is: In order to meet the mapping requirements, different GSD thresholds need to be set for different mapping scales. In one embodiment, the aforementioned mapping scale is 1:2000, and the ground resolution GSD of the lowest point in the survey area needs to be less than or equal to 16 cm. Preferably, when the mapping scale is 1:2000, the ground resolution GSD of the lowest point in the survey area is selected as 16 cm. If the mapping scale is 1:1000, the ground resolution GSD of the lowest point in the survey area needs to be equal to 8 cm. Preferably, when the mapping scale is 1:1000, the ground resolution GSD of the lowest point in the survey area needs to be selected as 8 cm. If the mapping scale is 1:500, the ground resolution GSD of the lowest point in the survey area needs to be equal to 5 cm. Preferably, when the mapping scale is 1:500, the ground resolution GSD of the lowest point in the survey area is selected as 5 cm.

[0038] Step S120, determine the layout distance of the image control points in the heading direction and the layout distance in the lateral direction. The layout distance of the image control points in the heading direction is calculated by the length of the single image baseline in the heading direction and the baseline span of the heading image control points. The calculation formula (2) for the length of the single image baseline in the heading direction is: x =L x ×(1-P x )×a(2), where b x Indicates the length of the heading single picture baseline, L x Indicates the heading amplitude or pixel of the digital image, P x It represents the heading overlap of digital images, and a represents the pixel size of the camera carried by the UAV.

[0039] The lateral layout distance of the image control points is calculated by the lateral single image baseline length and the lateral image control point baseline span. The calculation formula (3) of the lateral single image baseline length is: y =L y ×(1-P y )×a(3), where b y Indicates the baseline length of a single lateral image, L yIndicates the lateral amplitude or pixel of a digital image, P y It represents the lateral overlap of digital images, and a represents the camera pixel size.

[0040] The layout distance of the image control points in the heading and lateral directions can be obtained by the product of the heading image control point baseline span and the length of the single picture baseline in the heading direction, and the product of the lateral image control point baseline span and the length of the single picture baseline in the lateral direction. In a specific embodiment, when the mapping scale is 1:2000, the heading image control point baseline span can be 6, and the layout distance of the image control points in the heading direction is 6 times the length of the single picture baseline in the heading direction. If the mapping scale is 1:1000, the heading image control point baseline span can be 4, and the layout distance of the image control points in the heading direction is 4 times the length of the single picture baseline in the heading direction. If the mapping scale is 1:500, the heading image control point baseline span can be 3, and the layout distance of the image control points in the heading direction is 3 times the length of the single picture baseline in the heading direction. In another specific embodiment, the span of the lateral route can be set to 3 at different mapping scales, and the layout distance of the image control points in the lateral direction is 3 times the length of the baseline of a single image in the lateral direction.

[0041] Step S130, according to the layout distance of the image control points in the heading direction and the layout distance in the lateral direction, determine the layout position of the image control points within the measurement area in each of the rectangular areas. In one embodiment, on the Aowei map software, the first position of the image control points can be selected in the form of point groups at the four corners of each rectangular area, and each point group includes at least 3 points. That is, adjacent rectangular areas can use the image control points on the same group of four corners, which greatly reduces the number of image control points to be laid out and improves work efficiency. Then, based on the layout distance requirements in the heading and lateral directions obtained in the above steps, the image control points are evenly laid out in each rectangular area, that is, the second position of all the image control points is determined, and the second position of the laid image control points is determined according to the first position and the layout distance in the heading and lateral directions.

[0042] In the specific implementation, based on the second position of all image control points on the Aowei map, field personnel can choose a location with flat terrain, no obstructions above, and not easily touched according to actual judgment at the river site, and use methods such as spray painting and mold fixing to deploy the actual image control points. At the same time, the global positioning system and real-time dynamic carrier phase difference technology (GPS-RTK) are used to collect the actual three-dimensional coordinates of the image control points.

[0043] In one embodiment, the scope of the drone aerial survey of the water conservancy project of the present application is a short-distance serpentine area of ​​the river channel, and the type of drone and the type of camera carried are selected according to the following method: the number of river channel bends within the survey area is less than or equal to a first preset value, that is, the river channel has fewer bends, and the drone uses a fixed-wing or compound-wing drone and is equipped with a full-frame camera; the number of river channel bends within the survey area is greater than the first preset value, that is, the river channel has more bends, and the drone uses a fixed-wing or compound-wing drone and is equipped with a full-frame camera; or, the area of ​​the rectangular area is greater than the second preset value, that is, the area of ​​the divided single rectangular area is larger, and the drone uses a fixed-wing or compound-wing drone and is equipped with a full-frame camera; the area of ​​the rectangular area is greater than the second preset value, that is, the area of ​​the divided single rectangular area is smaller, and the drone uses a fixed-wing or compound-wing drone and is equipped with a full-frame camera.

[0044] The second aspect of the present application provides a UAV aerial survey image control point layout system for water conservancy projects. Figure 2 As shown, the drone aerial survey image control point layout system for water conservancy projects of the present application includes a survey area segmentation module, an image control point distance calculation module and an image control point selection module. Among them, the survey area segmentation module is used to determine the survey area range of the river channel. Based on the direction of the river channel and the area of ​​a single drone aerial photography, the survey area range is divided into multiple rectangular areas in an overlapping manner, and the overlapping distance of adjacent rectangular areas in the direction of the river channel is at least the flight height of a drone during aerial survey.

[0045] The calculation process of the above-mentioned flight altitude is to determine the ground resolution GSD based on the map scale, the camera pixel size a and the focal length f to determine the flight altitude H. The calculation formula (1) of the flight altitude H is: In order to meet the mapping requirements, different GSD thresholds need to be set for different mapping scales. In a specific embodiment, the aforementioned mapping scale is 1:2000, and the ground resolution GSD of the lowest point in the survey area needs to be better than 16 cm. If the mapping scale is 1:1000, the ground resolution GSD of the lowest point in the survey area needs to be better than 8 cm. If the mapping scale is 1:500, the ground resolution GSD of the lowest point in the survey area needs to be better than 5 cm.

[0046] The image control point distance calculation module is used to determine the layout distance of the image control points in the heading direction and the layout distance in the lateral direction. The layout distance of the image control points in the heading direction is obtained by calculating the product of the single image baseline length in the heading direction and the heading image control point baseline span. Specifically, the calculation formula (2) for the single image baseline length in the heading direction is: x =L x ×(1-P x )×a(2), where b x Indicates the length of the heading single picture baseline, L x Indicates the heading amplitude or pixel of the digital image, Px It represents the heading overlap of digital images, and a represents the pixel size of the camera carried by the UAV.

[0047] The lateral layout distance of the image control points is calculated by the lateral single image baseline length and the lateral image control point baseline span. The calculation formula (3) of the lateral single image baseline length is: y =L y ×(1-P y )×a(3), where b y Indicates the baseline length of a single lateral image, L y Indicates the lateral amplitude or pixel of a digital image, P y It represents the lateral overlap of digital images, and a represents the camera pixel size.

[0048] The aforementioned image control point selection module is used to determine the image control point layout positions within the measurement area in each of the rectangular areas according to the layout distance of the image control points in the heading direction and the layout distance in the lateral direction. In the Aowei map software, the first position of the image control points can be selected in the form of point groups at the four corners of each rectangular area, and each point group includes at least 3 points. Then, based on the layout distance of the image control points in the heading direction and the layout distance of the image control points in the lateral direction obtained by the image control point distance calculation module, the image control points are evenly laid out in each rectangular area to determine the second positions of all image control points.

[0049] like Figure 3 As shown, in one embodiment, the drone aerial survey image control point layout system for water conservancy projects of the present application may also include an equipment selection module, which is used to determine the operating drone and the camera equipment carried. For short-distance serpentine areas of the river, locations where the river has fewer bends, that is, areas where the curvature of the river changes gently, since the overall trend is relatively straight or smooth, the drone can operate along a more direct path during flight without frequently adjusting the flight direction and altitude. Therefore, the area of ​​a single partition that can be divided is larger, which is suitable for fixed-wing or compound-wing drones equipped with full-frame cameras. The drone can complete shooting or monitoring tasks in this area with higher efficiency without frequent takeoffs and landings or adjustments to the flight plan.

[0050] For locations with many bends in the river, that is, areas where the curvature of the river changes frequently, if a larger partition area is still used for operation, the drone will have to frequently shuttle between narrow bends, which will not only reduce the operation efficiency, but also increase the flight risk. Therefore, the area of ​​a single partition that can be divided is smaller, which is suitable for rotary-wing drones, equipped with full-frame or half-frame drones. Based on this, the drone can complete the operation relatively independently in each small partition, reducing the complexity and uncertainty of the flight path, and improving the safety and efficiency of the operation.

[0051] It should be understood that the specific process of each module executing the above corresponding steps has been described in detail in the above method embodiment, and for the sake of brevity, it will not be repeated here.

[0052] It should also be understood that the division of modules in the embodiments of the present application is schematic and is only a logical function division. There may be other division methods in actual implementation. In addition, each functional module in each embodiment of the present application may be integrated into a processor, or may exist physically separately, or two or more modules may be integrated into one module. The above-mentioned integrated modules may be implemented in the form of hardware or in the form of software functional modules.

[0053] Figure 4 is a schematic block diagram of a computer device / equipment / system provided in an embodiment of the present application. Figure 4 As shown, the computer device includes: at least one processor 401, a memory 402, at least one network interface 403 and a user interface 405. The various components in the device are coupled together through a bus system 404. It can be understood that the bus system 404 is used to achieve connection and communication between these components. In addition to the data bus, the bus system 404 also includes a power bus, a control bus and a status signal bus. However, for the sake of clarity, Figure 4 In the specification, various buses are labeled as bus systems.

[0054] The user interface 405 may include a display, a keyboard, a mouse, a trackball, a click gun, keys, buttons, a touch pad or a touch screen.

[0055] It is understood that the memory 402 can be a volatile memory or a non-volatile memory, and can also include both volatile and non-volatile memories. Among them, the non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), which is used as an external cache. By way of example but not limitation, many forms of RAM are available, such as static random access memory (SRAM), synchronous static random access memory (SSRAM). The memory described in the embodiments of the present invention is intended to include but is not limited to these and any other suitable categories of memory.

[0056] The memory 402 in the embodiment of the present invention is used to store various types of data to support the operation of the electronic terminal 400. Examples of these data include: any executable program used to operate on the electronic terminal 400, such as an operating system 4021 and an application 4022; the operating system 4021 includes various system programs, such as a framework layer, a core library layer, a driver layer, etc., for implementing various basic services and processing hardware-based tasks. The application 4022 can include various applications, such as a media player (Media Player), a browser (Browser), etc., for implementing various application services. The implementation of the XX method provided in the embodiment of the present invention can be included in the application 4022.

[0057] The method disclosed in the above embodiment of the present invention can be applied to the processor 401, or implemented by the processor 401. The processor 401 may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by the hardware integrated logic circuit in the processor 401 or the instruction in the form of software. The above processor 401 may be a general processor, a digital signal processor (DSP, Digital Signal Processor), or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. The processor 401 can implement or execute the various methods, steps and logic block diagrams disclosed in the embodiment of the present invention. The general processor 401 may be a microprocessor or any conventional processor, etc. In combination with the steps of the accessory optimization method provided in the embodiment of the present invention, it can be directly embodied as a hardware decoding processor to execute, or it can be executed by a combination of hardware and software modules in the decoding processor. The software module can be located in a storage medium, which is located in a memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware.

[0058] In an exemplary embodiment, the electronic terminal 400 may be implemented by one or more application specific integrated circuits (ASIC), DSP, programmable logic device (PLD), complex programmable logic device (CPLD) to execute the aforementioned method.

[0059] According to the method provided in the embodiment of the present application, the present application also provides a computer-readable storage medium, which stores a program code. When the program code runs on a computer, the computer executes the method provided in the first aspect of the present application.

[0060] The terms "component", "module", "system", etc. used in this specification are used to represent computer-related entities, hardware, firmware, a combination of hardware and software, software, or software in execution. For example, a component can be, but is not limited to, a process running on a processor, a processor, an object, an executable file, an execution thread, a program and / or a computer. By way of illustration, both applications running on a computing device and a computing device can be components. One or more components may reside in a process and / or an execution thread, and a component may be located on a computer and / or distributed between two or more computers. In addition, these components may be executed from various computer-readable media having various data structures stored thereon. Components may, for example, communicate through local and / or remote processes according to signals having one or more data packets (e.g., data from two components interacting with another component between a local system, a distributed system and / or a network, such as the Internet interacting with other systems through signals).

[0061] Those of ordinary skill in the art will appreciate that the various illustrative logical blocks and steps described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or in 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 may 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.

[0062] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0063] In the several embodiments provided in the present 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 only schematic. For example, the division of units is only a logical function division. There may be other division methods in actual implementation. For example, 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.

[0064] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0065] 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.

[0066] In the above embodiments, the functions of each functional unit can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions (programs). When loading and executing computer program instructions (programs) on a computer, the process or function according to the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. Computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, computer instructions can be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (digital subscriber line, DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that contains one or more available media integrations. Available media may be magnetic media (e.g., floppy disks, hard disks, tapes), optical media (e.g., high-density digital video discs (DVDs), or semiconductor media (e.g., solid state disks (SSDs), etc.).

[0067] 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, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the various embodiments of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, and other media that can store program codes.

[0068] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present application. These improvements and substitutions should also be regarded as the scope of protection of the present application.

Claims

1. A method for setting control points for drone aerial surveying of water conservancy projects, characterized in that: include: Determine the survey area of ​​the river channel, and divide the survey area into multiple rectangular areas in an overlapping manner based on the direction of the river channel and the area of ​​a single drone aerial survey. The overlapping distance of adjacent rectangular areas in the direction of the river channel is at least the flight height of a drone during aerial survey. Determine the layout distance of the image control points in the heading direction and the layout distance in the lateral direction; where: The layout distance on the heading is calculated by the length of the baseline of a single picture on the heading and the baseline span of the heading image control point. The calculation formula of the length of the baseline of a single picture on the heading is b x =L x ×(1-P x )×a, where b x Indicates the length of the heading single picture baseline, L x Indicates the heading amplitude or pixel of the digital image, P x It represents the heading overlap of digital images, and a represents the pixel size of the camera carried by the drone; The lateral layout distance is calculated by the lateral single image baseline length and the lateral image control point baseline span. The calculation formula of the lateral single image baseline length is: y =L y ×(1-P y )×a, where b y Indicates the baseline length of a single lateral image, L y Indicates the lateral amplitude or pixel of a digital image, P y Indicates the lateral overlap of digital images; According to the layout distance of the image control points in the heading direction and the layout distance in the lateral direction, the layout positions of the image control points within the measurement area are determined in each of the rectangular areas.

2. The method for placing control points for drone aerial surveying of water conservancy projects according to claim 1, characterized in that: Determining the layout positions of image control points within the measurement area includes: The first positions of image control points are selected in the form of point groups at the four corners of each of the rectangular areas, and each point group includes at least three points.

3. The method for placing control points for drone aerial surveying of water conservancy projects according to claim 2, characterized in that: The step of determining the layout positions of the image control points within the measurement area further includes: The second position of the image control point is determined based on the first position and the layout distance of the image control point in the heading direction and the layout distance in the lateral direction.

4. The method for placing control points for drone aerial surveying of water conservancy projects according to claim 1, characterized in that: When determining the layout positions of the image control points within the measurement area, When the map scale is 1:2000, the baseline span of the heading image control points is 6, and the layout distance of the image control points in the heading is 6 times the length of the baseline of a single image in the heading; When the mapping scale is 1:1000, the baseline span of the heading image control points is pseudo 4, and the layout distance of the image control points in the heading is 4 times the length of the baseline of a single image in the heading; When the mapping scale is 1:500, the heading image control point baseline span is 3, and the layout distance of the image control points in the heading direction is 3 times the length of the single image baseline in the heading direction; The span of the lateral routes is 3 at different map scales, and the layout distance of the image control points in the lateral direction is 3 times the length of the baseline of a single image in the lateral direction.

5. The method for placing control points for drone aerial surveying of water conservancy projects according to claim 1, characterized in that: Using formula Determine the altitude of the drone during aerial survey, where GSD represents the ground resolution of the lowest point in the rectangular area, a represents the pixel size of the camera carried by the drone, f represents the focal length of the camera, and H represents the altitude of the drone during aerial survey.

6. The method for placing control points for drone aerial surveying of water conservancy projects according to claim 5, characterized in that: The type of drone and the type of camera carried are selected as follows: If the number of river bends within the survey area is less than or equal to a first preset value, the drone is a fixed-wing or compound-wing drone equipped with a full-frame camera; If the number of river bends within the survey area is greater than a first preset value, the drone is a fixed-wing or compound-wing drone equipped with a full-frame camera; Alternatively, the area of ​​the rectangular region is greater than the second preset value, and the drone is a fixed-wing or composite-wing drone equipped with a full-frame camera; The area of ​​the rectangular region is less than or equal to a second preset value, and the drone is a fixed-wing or compound-wing drone equipped with a full-frame camera.

7. The method for placing control points for drone aerial surveying of water conservancy projects according to claim 5, characterized in that: When determining the altitude of the drone during aerial survey, When the map scale is 1:2000, the ground resolution of the lowest point in the rectangular area is less than or equal to 16 cm; When the map scale is 1:1000, the ground resolution of the lowest point in the rectangular area is less than or equal to 8 cm; When the map scale is 1:500, the ground resolution of the lowest point in the rectangular area is less than or equal to 5 cm.

8. A UAV aerial survey image control point layout system for water conservancy projects, characterized in that: It includes a measurement area segmentation module, an image control point distance calculation module and an image control point selection module; The survey area segmentation module is used to determine the survey area range of the river channel. Based on the direction of the river channel and the area of ​​a single drone aerial photography, the survey area range is segmented in an end-to-end overlapping manner to obtain multiple rectangular areas, and the overlapping distance of adjacent rectangular areas in the river channel flow direction is at least the flight height of a drone during aerial survey; The image control point distance calculation module is used to determine the layout distance of the image control points in the heading direction and the layout distance in the lateral direction; The image control point selection module is used to determine the layout positions of the image control points within the measurement area in each of the rectangular areas according to the layout distances of the image control points in the heading direction and in the lateral direction.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

10. A computer electronic terminal, comprising a memory, a processor and a computer program stored in the memory, characterized in that: The processor executes the computer program to implement the method according to any one of claims 1 to 7.

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