A method for estimating building elevation based on contour vector registration

Abstract

An embodiment of the present application discloses a method for estimating the elevation of a building based on contour vector registration, which relates to the field of photogrammetry and remote sensing technology. Specifically, it includes: extracting the first building vector contour corresponding to the same target building from multi-view satellite images; determining the elevation search range and elevation step size; projecting the first building vector contour of other images except the reference image to the object space to obtain the second building vector contour, projecting the second building vector contour to the reference image to obtain the third building vector contour on the reference image and calculating the overlapping area ratio between it and the reference building vector contour; moving the elevation step size within the elevation search range to obtain the relationship function between the overlapping area ratio and the elevation value, and determining the elevation value of the target building by interpolation method, and outputting the height of the target building. The present application has advantages such as fast calculation speed and high accuracy, can provide new ideas for obtaining building elevation information, and provide data support for urban three-dimensional modeling.

Description

Technical Field

[0001] This application relates to the technical field of photogrammetry and remote sensing, and particularly to a method for estimating building elevation based on contour vector registration. Background Art

[0002] The height information of urban buildings, as basic data and important parameters, can reflect the vertical information of the city from the side. At present, the height of buildings is mainly measured by traditional surveying methods and measurement methods based on remote sensing technology.

[0003] Among them, traditional surveying methods include total station measurement, GPS measurement, laser scanning measurement, etc. This method has mature technology and high measurement accuracy, but it has high measurement costs, long time consumption, certain requirements for personnel experience and equipment operation level, requires a large amount of manpower, and is difficult to meet the needs of rapid measurement.

[0004] Measurement methods based on remote sensing technology mainly include shadow length detection method, homologous point image matching method, dense matching method, etc. Compared with traditional surveying methods, these methods have the advantages of high efficiency, fast speed, wide coverage, etc. Among them, the shadow length detection method can estimate the building height by using the building shadow length in a single satellite image combined with information such as image photography time and azimuth. This method is simple to operate and has low implementation costs, but it is easily affected by environmental factors such as lighting conditions and terrain, and will produce large errors under the influence of environmental factors that are not conducive to detection; the homologous point image matching method can calculate the building height by forward intersection by matching the homologous image points of homologous buildings in multi-view satellite images and according to the image geometric positioning parameters. However, the success rate and reliability of homologous point matching depend on the richness of image texture, and generally the building roof lacks texture, so the success rate and reliability of this method are severely reduced; the dense matching method uses stereo images to reconstruct the three-dimensional surface information of buildings through dense matching algorithms. This method is also affected by the lack of texture in the building roof images.

[0005] Therefore, there is currently a lack of a method that is simple to operate and can quickly and easily obtain building elevation information. Summary of the Invention

[0006] The embodiments of this application provide a method, device, equipment, and storage medium for estimating building elevation based on contour vector registration to solve the defects in the above-mentioned related technologies. The technical solutions are as follows:

[0007] In a first aspect, the embodiments of this application provide a method for estimating building elevation based on contour vector registration, including:

[0008] Obtain satellite images of at least two perspectives, and extract the first building vector contour in each of the satellite images through a trained building contour extraction model;

[0009] Pair all the first building vector contours to determine the first building vector contours corresponding to the same target building;

[0010] Determine the elevation search range of the target building, and project the first building vector contours of other images except the reference image to the object space respectively based on each elevation value in the elevation search range to obtain the second building vector contours corresponding to each first building vector contour at different elevation values;

[0011] Project each of the second building vector contours to the reference image to obtain the third building vector contours on the reference image;

[0012] Calculate the overlapping area ratio between each of the third building vector contours and the reference building vector contour of the reference image, and determine the building elevation value of the target building based on the variation relationship between the overlapping area ratio and the corresponding elevation value;

[0013] Output the height of the target building based on the building elevation value.

[0014] In an alternative scheme of the first aspect, the pairing of all the first building vector contours to determine the first building vector contours corresponding to the same target building includes:

[0015] Calculate the contour similarity between every two of the first building vector contours based on the geographical location, coverage area, number of vector nodes, and vector contour shape of each of the first building vector contours;

[0016] The first building vector contours with the calculated contour similarity greater than the contour similarity threshold are the first building vector contours corresponding to the same target building.

[0017] In an alternative scheme of the first aspect, the determination of the elevation search range of the target building includes:

[0018] According to the digital elevation model and the geographical range covered by the target building on the corresponding satellite image, obtain the maximum elevation value and the minimum elevation value of all grid points within the geographical range, and determine the elevation search range based on the maximum elevation value and the minimum elevation value.

[0019] In an alternative scheme of the first aspect, after determining the elevation search range of the target building, it further includes:

[0020] Determine the first ground point corresponding to the object space when the preset reference point on the other image is at the maximum elevation value, and the second ground point corresponding to the object space when the elevation is at the minimum elevation value;

[0021] Project the first ground point and the second ground point onto the reference image respectively to obtain corresponding projection points;

[0022] Determine the elevation step based on the ratio of the distance between the first ground point and the second ground point to the distance between the projection points;

[0023] Determine each elevation value in the elevation search range based on the elevation step and the minimum elevation value.

[0024] In an alternative embodiment of the first aspect, the step of projecting the first building vector contour of other images except the reference image onto the object space respectively based on each elevation value in the elevation search range to obtain the second building vector contour corresponding to each first building vector contour at different elevation values includes:

[0025] Project the first building vector contour onto the object space based on the minimum elevation value to obtain the second building vector contour corresponding to the first building vector contour at the minimum elevation value;

[0026] Accumulate the elevation step based on the minimum elevation value to update the elevation value, and respectively execute the step of projecting the first building vector contour onto the object space based on the updated elevation value to obtain the second building vector contour corresponding to the first building vector contour at the current elevation value.

[0027] In an alternative embodiment of the first aspect, the step of calculating the overlapping area ratio of each third building vector contour and the reference building vector contour of the reference image includes:

[0028] Obtain the overlapping area of each third building vector contour and the reference building vector contour respectively, and calculate the overlapping area ratio of each overlapping area to the overlapping area of the reference building vector contour;

[0029] Determine the change relationship between the elevation values corresponding to all the third building vector contours and the overlapping area ratio, obtain the elevation value corresponding to the maximum overlapping area ratio, and determine the building elevation value of the target building based on the elevation value corresponding to the maximum overlapping area ratio.

[0030] In an alternative embodiment of the first aspect, the step of outputting the height of the target building based on the building elevation value includes:

[0031] Obtain the ground elevation value of the horizontal reference plane in the area where the target building is located;

[0032] Calculate the difference between the building elevation value and the ground elevation value, and output the difference as the height of the target building.

[0033] In a second aspect, an embodiment of the present application further provides a building elevation estimation device based on contour vector registration, including:

[0034] A contour extraction module, configured to obtain satellite images from at least two perspectives, and extract the first building vector contour in each of the satellite images through a trained building contour extraction model;

[0035] A contour pairing module, configured to pair all the first building vector contours to determine the first building vector contours corresponding to the same target building;

[0036] A vector registration module, configured to determine the elevation search range of the target building, and project the first building vector contours of other images except the reference image to the object space based on each elevation value in the elevation search range, to obtain the second building vector contours corresponding to each first building vector contour at different elevation values;

[0037] The vector registration module is further configured to project each of the second building vector contours to the reference image to obtain the third building vector contours on the reference image;

[0038] A height calculation module, configured to calculate the overlapping area ratio between each of the third building vector contours and the reference building vector contour of the reference image, and determine the building elevation value of the target building based on the change relationship between the overlapping area ratio and the corresponding elevation value;

[0039] The height calculation module is further configured to output the height of the target building based on the building elevation value.

[0040] In a third aspect, an embodiment of the present application further provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor, where when the processor executes the program, it implements the method provided in the first aspect or any implementation manner of the first aspect of the embodiments of the present application.

[0041] In a fourth aspect, the present application further provides a non-transitory computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the method provided in the first aspect or any implementation manner of the first aspect of the embodiments of the present application.

[0042] The beneficial effects brought by the technical solutions provided in some embodiments of the present application at least include:

[0043] In the embodiment of the present application, a method of deep learning is used to extract and match the vector contours of buildings in multi-view satellite images, estimate the value range of the building roof elevation, that is, the elevation search range, calculate the search elevation step distance, and assume the roof elevation of the building within the elevation search range; further, the rational function model is used to project the image-side building contours of other images to the object side, and then project the object-side building contours to the reference image; subsequently, calculate the matching degree between the projected contour polygon and the corresponding contour polygon of the original reference image (completed by calculating the overlapping area ratio), and obtain the elevation value with the best matching degree by changing the elevation value through the elevation step distance as the roof elevation of the building; finally, subtract the ground elevation from the building roof elevation to determine the building height, thereby providing key data for the 3D reconstruction of the building. The embodiment of the present application has the advantages of simple operation, fast calculation speed, high calculation accuracy, etc., can provide new ideas for obtaining building elevation information, and can provide accurate data support for urban 3D modeling. Description of the Drawings

[0044] In order to more clearly illustrate the technical solutions in the present application or related technologies, the following will briefly introduce the drawings required for use in the description of the embodiments or related technologies. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0045] Figure 1 It is a schematic flowchart of a method for estimating building elevation based on contour vector registration provided by an embodiment of the present application;

[0046] Figure 2 It is a schematic diagram for calculating the elevation step distance of a method for estimating building elevation based on contour vector registration provided by an embodiment of the present application;

[0047] Figure 3 It is a schematic flowchart of a method for estimating building elevation based on contour vector registration provided by an embodiment of the present application;

[0048] Figure 4 It is a schematic diagram of vector registration of a method for estimating building elevation based on contour vector registration provided by an embodiment of the present application;

[0049] Figure 5 It is a schematic diagram of the change relationship between the elevation value and the overlapping area ratio of a method for estimating building elevation based on contour vector registration provided by an embodiment of the present application;

[0050] Figure 6 It is a schematic structural diagram of a device for estimating building elevation based on contour vector registration provided by an embodiment of the present application;

[0051] Figure 7 It is a schematic structural diagram of an electronic device provided by an embodiment of the present application. Detailed implementation manners

[0052] To make the objectives, technical solutions, and advantages of the present application clearer, the technical solutions in the present application will be clearly and completely described below with reference to the accompanying drawings in the present application. Apparently, the described embodiments are some but not all of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the protection scope of the present application.

[0053] The terms "including" and "having" and any variations thereof in the specification and claims of the present application and the above accompanying drawings are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or modules is not limited to the listed steps or modules, but optionally further includes steps or modules not listed, or optionally further includes other steps or modules inherent to these processes, methods, products, or devices.

[0054] It should be noted that the terms "first" and "second" involved in the present application are only used to distinguish similar objects and do not represent a specific order for the objects. Understandably, "first" and "second" can be interchanged with a specific order or sequence when permitted. It should be understood that the objects distinguished by "first" and "second" can be interchanged appropriately so that the embodiments of the present application described herein can be implemented in an order other than those described or illustrated herein.

[0055] It should be noted that remote sensing images can be interpreted based on deep learning. Combining with the Segment Anything Model (SAM), the method of automatically identifying buildings from satellite images and extracting contour vectors can be gradually improved. A building elevation estimation method based on contour vector registration proposed in the present application can first estimate the value range of the building roof elevation in combination with related technologies, and by traversing the elevation, maximize the overlapping area of the paired building vector contours extracted from multi-view images to achieve the registration of contour vectors, thereby determining the height of the building.

[0056] The present application will be described in detail below with reference to specific embodiments.

[0057] Next, in combination with Figure 1 , taking the terminal executing the building elevation estimation method based on contour vector registration as an example, the building elevation estimation method based on contour vector registration provided by the embodiments of the present application will be introduced. For details, please refer to Figure 1 , Figure 1The figure shows a schematic flowchart of a building elevation estimation method based on contour vector registration provided by an embodiment of the present application. As Figure 1 shown, the method includes the following steps:

[0058] S101. Obtain satellite images from at least two perspectives, and extract the first building vector contours in each of the satellite images through a trained building contour extraction model.

[0059] S102. Pair all the first building vector contours to determine the first building vector contours corresponding to the same target building.

[0060] S103. Determine the elevation search range of the target building, and project the first building vector contours of other images except the reference image onto the object space based on each elevation value in the elevation search range, so as to obtain the second building vector contours corresponding to each first building vector contour at different elevation values.

[0061] S104. Project each second building vector contour onto the reference image to obtain the third building vector contour on the reference image.

[0062] S105. Calculate the overlapping area ratio between each third building vector contour and the reference building vector contour of the reference image, and determine the building elevation value of the target building based on the change relationship between the overlapping area ratio and the corresponding elevation value.

[0063] S106. Output the height of the target building based on the building elevation value.

[0064] Specifically, in S101, high-resolution satellite images from multiple perspectives can be obtained, and the building vector contours in each satellite image can be extracted by using a trained building extraction model, that is, the first building vector contour corresponding to each satellite image is obtained. It can be understood that the first building vector contour is located in the image space of each satellite image.

[0065] Specifically, one of the images from multiple perspectives of high-resolution satellite images can be used as the reference image, such as the main view image, and the images from other perspectives except the reference image are denoted as other images. For the reference image, the first building vector contour of the reference image is the reference building vector contour.

[0066] In some embodiments, vector contour pairing can be performed in S102. Specifically, the contour similarity between every two first building vector contours can be calculated based on the geographical location, coverage area, number of vector nodes, and vector contour shape of each first building vector contour, and the first building vector contours with a contour similarity greater than the contour similarity threshold are the first building vector contours corresponding to the same target building.

[0067] In some embodiments, the elevation search range in S103 can be obtained based on the digital elevation model and the geographical range covered by the target building on the corresponding satellite image, and the maximum elevation value and the minimum elevation value of all grid points within the corresponding geographical range can be determined. The elevation search range is determined based on the maximum elevation value and the minimum elevation value.

[0068] It can be understood that, through the existing digital elevation model and the geographical range of the building in the captured satellite image, the elevation value of each grid point within the coverage range of the image can be easily obtained. The coverage range of the elevation value can be expanded based on the existing elevation values, that is, an elevation variable is added to the maximum elevation value determined through the grid point elevation values, and / or an elevation variable is subtracted from the minimum elevation value determined through the grid point elevation values, so as to obtain an expanded elevation search range to cover the possible building heights.

[0069] Specifically, the obtained elevation search range can be expressed as [z min , z max , where z min is the minimum elevation value and z max is the maximum elevation value.

[0070] In some embodiments, in S103, the elevation step calculation as Figure 2 shown can determine the elevation step of the elevation search range, including:

[0071] Select the P point on other images as the preset reference point. For example, select the center point of the building vector contour, and determine the first ground point Q max corresponding to the object space when the elevation of the preset reference point P on other images takes the maximum elevation value z 1 , and the second ground point Q min corresponding to the object space when the elevation takes the minimum elevation value z 2 ; project the first ground point Q 1 and the second ground point Q 2 onto the reference image to obtain the corresponding projection points, and obtain the corresponding image points P 1 and P 2 on the reference image respectively;

[0072] Based on the ratio of the distance Q 1 between the first ground point Q 2 and the second ground point Q 1 Q 2 and the distance P 1 P 2 between the projection points, determine the elevation step Δz;

[0073] Based on the elevation step Δz and the minimum elevation z min Determine each elevation value within the elevation search range.

[0074] Exemplarily, when the preset reference point P reaches the maximum elevation z max the corresponding ground point is Q 1 (X 1 , Y 1 , Z 1 ), and its corresponding image point after projection onto the reference image is P 1 (x 1 , y 1 ); when the point P reaches the minimum elevation z min the corresponding ground point is Q 2 (X 2 , Y 2 , Z 2 ), and its corresponding image point after projection onto the reference image is P 2 (x 2 , y 2 ), then the calculation of the elevation step can apply the formula:

[0075]

[0076] Specifically, a rational function model can be used to convert between the object coordinates of the ground point and the image coordinates of the image point. The rational function model is a general imaging model for describing the correspondence between the image coordinates (l n , s n ) of a certain point on the satellite image and the three-dimensional geographic coordinates (X n , Y n , Z n ) of its corresponding ground point. The coefficients of this model are rational polynomial coefficients (RPC). Apply the formula:

[0077]

[0078] where n is any pixel; l n , s n are the normalized image point coordinates; X n , Y n , Z n are the normalized ground point coordinates; according to the rational function mathematical model, P(X n , Y n , Z n ) is a cubic polynomial, and the rational polynomial coefficients (RPC parameters) are provided by the satellite image operator and refined through block adjustment of the image area.

[0079] In some embodiments, such asFigure 3 As shown in the figure, S103 and S104 may specifically include the following steps:

[0080] S301: Combine the rational polynomial coefficients of the first building vector contour and other images, and project the first building vector contour to the object space based on the rational function model according to the given elevation value to obtain the second building vector contour corresponding to the given elevation value of the first building vector contour; specifically, select the minimum elevation value z min as the first given elevation value z 0 .

[0081] S302: Based on the rational polynomial coefficients of the reference image, project the second building vector contour in the object space back to the reference image through the rational function model to obtain the third building vector contour on the reference image.

[0082] S303: Accumulate the elevation step on the basis of the given elevation value z 0 , that is:

[0083] z i = z min + i·ΔZ, where i is an integer not less than 0;

[0084] If the updated elevation value z i is less than or equal to the maximum elevation value z max , then perform the step of projecting the first building vector contour to the object space in S301 based on the updated elevation value to obtain the second building vector contour corresponding to the current elevation value of the first building vector contour, and the step of back-projecting the second building vector contour in the object space to the reference image in S302 to obtain the third building vector contour on the reference image.

[0085] S304: If the updated elevation value z i is greater than the maximum elevation value z max , output the third building vector contour corresponding to each elevation value in the elevation search range of other images.

[0086] Exemplarily, as Figure 4 shown in the vector registration schematic diagram, first project the first building vector contour of other images to the object space through S301, project each elevation value separately to obtain the second building vector contour corresponding to each elevation value; further, back-project the second building vector contour corresponding to each elevation value from the object space to the reference image to obtain the third building vector contour on the reference image, Figure 4 in which an example of taking the elevation value as z min , z max corresponding third building vector contour is shown, where z bestThe building vector contour corresponding to the estimated optimal building elevation value, z best It needs to be obtained after traversing each elevation value and comparing each third building vector contour with the reference building vector contour of the reference image.

[0087] In some embodiments, in S105, the overlapping area of each third building vector contour and the reference building vector contour can be obtained respectively, and the overlapping area ratio of each overlapping area to the overlapping area of the reference building vector contour can be calculated;

[0088] Determine the change relationship between the elevation value corresponding to all third building vector contours and the overlapping area ratio, obtain the elevation value corresponding to the maximum value of the overlapping area ratio, and determine the building elevation value of the target building based on the elevation value corresponding to the maximum value of the overlapping area ratio.

[0089] Assume that the graphic area of the third building vector contour is S′, and the graphic area of the reference building vector contour in the original reference image is S, then the overlapping area ratio α is:

[0090]

[0091] Specifically, the overlapping area ratio α represents the intersection area ratio of two vector graphics and can be used to reflect the correlation between the two.

[0092] Optionally, each building vector contour can be regarded as a polygon defined by multiple vertex coordinates, and the area calculation can apply the formula:

[0093]

[0094] In some embodiments, the elevation value corresponding to each third building vector contour can be used as a function, and the corresponding overlapping area ratio can be used as a function value to fit the change relationship between the elevation value corresponding to all third building vector contours and the overlapping area ratio, and then determine the elevation value corresponding to the maximum value of the overlapping area ratio.

[0095] Exemplarily, a curve graph as shown in Figure 5 can be drawn. From the graph, it is easy to determine the change relationship between the elevation value and the overlapping area ratio, so as to determine the maximum value of the overlapping area ratio and the corresponding elevation value z best .

[0096] It should be noted that each elevation value obtained according to the elevation step cannot cover all elevation values. Parabolic fitting can be performed on the domain values, and the elevation value z with the largest overlapping area ratio can be obtained by interpolation. best , thereby obtaining the building elevation value, that is, the optimal roof elevation of the building.

[0097] In some embodiments, in S106, the ground elevation value of the horizontal reference plane of the area where the target building is located can be obtained; the difference between the building elevation value and the ground elevation value is calculated, and the corresponding difference is output as the height of the target building.

[0098] Specifically, the ground elevation z of the building can be extracted from the digital elevation model ground , and the height of the target building is the difference between the two, that is, z best - z ground .

[0099] In some embodiments, the measurement area can be selected, and the steps of S101 - S106 can be repeated for each building in the area, so as to obtain the height of each building in the corresponding area.

[0100] The following is an apparatus embodiment of the present application, which can be used to execute the method embodiment of the present application. For details not disclosed in the apparatus embodiment of the present application, please refer to the method embodiment of the present application.

[0101] Next, please refer to Figure 6 , which is a schematic structural diagram of a building elevation estimation apparatus based on contour vector registration provided for an exemplary embodiment of the present application. This apparatus can be implemented as all or part of a terminal through software, hardware, or a combination of both, and can also be integrated as an independent module on a server. The building elevation estimation apparatus based on contour vector registration in the embodiment of the present application can be applied to a terminal or the cloud. The apparatus 60 includes a contour extraction module 601, a contour pairing module 602, a vector registration module 603, and a height calculation module 604, where:

[0102] The contour extraction module 601 is used to obtain satellite images of at least two perspectives, and extract the first building vector contour in each of the satellite images through a trained building contour extraction model;

[0103] The contour pairing module 602 is used to pair all the first building vector contours to determine the first building vector contours corresponding to the same target building;

[0104] The vector registration module 603 is used to determine the elevation search range of the target building, and project the first building vector contours of other images except the reference image to the object space based on each elevation value in the elevation search range, so as to obtain the second building vector contours corresponding to each first building vector contour at different elevation values;

[0105] The vector registration module 603 is further used to project each second building vector contour to the reference image to obtain the third building vector contour on the reference image;

[0106] The height calculation module 604 is used to calculate the overlapping area ratio between each of the third building vector contours and the reference building vector contour of the reference image, and determine the building elevation value of the target building based on the variation relationship between the overlapping area ratio and the corresponding elevation value;

[0107] The height calculation module 604 is further used to output the height of the target building based on the building elevation value.

[0108] It should be noted that when the device 60 provided in the above embodiment executes the building elevation estimation method based on contour vector registration, only the above division of each functional module is used for illustration. In practical applications, the above functions can be allocated to different functional modules according to needs, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above. In addition, the device provided in the above embodiment and the embodiment of the building elevation estimation method based on contour vector registration belong to the same concept, and the implementation process thereof is detailed in the method embodiment, which will not be elaborated here.

[0109] An embodiment of the present application further provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, it implements the steps of the method in any of the above embodiments.

[0110] Please refer to Figure 7 for the structural block diagram of an electronic device provided by an embodiment of the present application.

[0111] As Figure 7 shown, the electronic device 700 includes a processor 701 and a memory 702.

[0112] In an embodiment of the present application, the processor 701 is the control center of the computer system, which can be the processor of a physical machine or the processor of a virtual machine. The processor 701 may include one or more processing cores, such as a 4-core processor or an 8-core processor. The processor 701 may be implemented in at least one hardware form of DSP (Digital Signal Processing), FPGA (Field-Programmable Gate Array), or PLA (Programmable Logic Array).

[0113] The processor 701 may also include a main processor and a co-processor. The main processor is a processor for processing data in the wake state, also known as the CPU (Central Processing Unit); the co-processor is a low-power processor for processing data in the standby state.

[0114] The memory 702 may include one or more computer-readable storage media, and the computer-readable storage media may be non-transitory. The memory 702 may further include high-speed random access memory and non-volatile memory, such as one or more disk storage devices and flash storage devices. In some embodiments of the present application, the non-transitory computer-readable storage media in the memory 702 is used to store at least one instruction, and the at least one instruction is used to be executed by the processor 701 to implement the method in the embodiments of the present application.

[0115] In some embodiments, the electronic device 700 further includes: a peripheral device interface 703 and at least one peripheral device 704. The processor 701, the memory 702, and the peripheral device interface 703 may be connected through a bus or signal lines. Each peripheral device 704 may be connected to the peripheral device interface 703 through a bus, signal lines, or a circuit board. Specifically, the peripheral device 704 includes: a display screen, a camera, and an audio circuit. The peripheral device interface 703 may be used to connect at least one peripheral device related to I / O (Input / Output) to the processor 701 and the memory 702.

[0116] In some embodiments of the present application, the processor 701, the memory 702, and the peripheral device interface 703 are integrated on the same chip or circuit board; in some other embodiments of the present application, any one or two of the processor 701, the memory 702, and the peripheral device interface 703 may be implemented on a separate chip or circuit board. The embodiments of the present application do not make specific limitations on this.

[0117] The block diagram of the electronic device structure shown in the embodiments of the present application does not constitute a limitation on the electronic device 700. The electronic device 700 may include more or fewer components than shown in the figure, or combine certain components, or adopt a different component layout.

[0118] The embodiments of the present application also provide a computer-readable storage medium, on which a computer program is stored. When the program is executed by a processor, the steps of the method in any of the foregoing embodiments are implemented. Among them, the computer-readable storage medium may include, but is not limited to, any type of disk, including floppy disks, optical disks, DVDs, CD-ROMs, microdrives, and magneto-optical disks, ROMs, RAMs, EPROMs, EEPROMs, DRAMs, VRAMs, flash memory devices, magnetic cards or optical cards, nanosystems (including molecular memory ICs), or any type of medium or device suitable for storing instructions and / or data.

[0119] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on such an understanding, the essence of the above technical solution, or the part that contributes to the related technology, can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disks, optical disks, etc., and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0120] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A building elevation estimation method based on contour vector registration, characterized in that: include: Acquire satellite images from at least two viewing angles, and extract the first building vector outline in each of the satellite images using a trained building outline extraction model; Pairing all of the first building vector outlines to determine a first building vector outline corresponding to the same target building; Determine the elevation search range of the target building, and project the first building vector outlines of the other images except the reference image to the object space based on each elevation value in the elevation search range, to obtain the second building vector outline corresponding to each of the first building vector outlines at different elevation values; Projecting each of the second building vector outlines onto the reference image to obtain a third building vector outline on the reference image; Calculating the overlapping area ratio between each of the third building vector outlines and the benchmark building vector outline of the benchmark image, and determining the building elevation value of the target building based on the changing relationship between the overlapping area ratio and the corresponding elevation value; The height of the target building is output based on the building elevation value.

2. A building elevation estimation method based on contour vector registration according to claim 1, characterized in that: The step of pairing all the first building vector outlines to determine the first building vector outline corresponding to the same target building includes: Calculate the outline similarity between every two first building vector outlines based on the geographical location, coverage area, number of vector nodes and vector outline shape of each first building vector outline; The first building vector outline whose outline similarity is greater than the outline similarity threshold is calculated as the first building vector outline corresponding to the same target building.

3. A building elevation estimation method based on contour vector registration according to claim 1 or 2, characterized in that: Determining the elevation search range of the target building includes: According to the digital elevation model and the geographical range covered by the target building on the corresponding satellite image, the maximum elevation value and the minimum elevation value of all grid points within the geographical range are obtained, and the elevation search range is determined based on the maximum elevation value and the minimum elevation value.

4. A building elevation estimation method based on contour vector registration according to claim 3, characterized in that: After determining the elevation search range of the target building, the method further includes: Determine a first ground point on the object side corresponding to the preset reference point on the other image when the elevation takes the maximum elevation value, and a second ground point on the object side corresponding to the preset reference point when the elevation takes the minimum elevation value; Projecting the first ground point and the second ground point onto the reference image to obtain corresponding projection points; Determine the elevation step based on the ratio of the distance between the first ground point and the second ground point to the distance between the projection points; Each elevation value in the elevation search range is determined based on the elevation step size and the elevation minimum value.

5. A building elevation estimation method based on contour vector registration according to claim 4, characterized in that: The method of projecting the first building vector outlines of the other images except the reference image to the object space based on each elevation value in the elevation search range to obtain the second building vector outlines corresponding to each of the first building vector outlines at different elevation values ​​includes: Projecting the first building vector outline to the object space based on the minimum elevation value to obtain the second building vector outline corresponding to the first building vector outline at the minimum elevation value; The elevation value is updated by accumulating the elevation step based on the minimum elevation value, and the step of projecting the first building vector outline to the object space is performed based on the updated elevation value to obtain the second building vector outline corresponding to the current elevation value of the first building vector outline.

6. A building elevation estimation method based on contour vector registration according to claim 1 or 4, characterized in that: The calculating the overlapping area ratio between each of the third building vector outlines and the reference building vector outline of the reference image comprises: Respectively obtain the overlapping area between each of the third building vector outlines and the reference building vector outline, and calculate the ratio of each overlapping area to the overlapping area of ​​the reference building vector outline; Determine the changing relationship between the elevation values ​​corresponding to all the third building vector contours and the overlapping area ratio, obtain the elevation value corresponding to the maximum value of the overlapping area ratio, and determine the building elevation value of the target building based on the elevation value corresponding to the maximum value of the overlapping area ratio.

7. A building elevation estimation method based on contour vector registration according to claim 1, characterized in that: The step of outputting the height of the target building based on the building elevation value comprises: Obtaining the ground elevation value of the horizontal reference plane in the area where the target building is located; The difference between the building elevation value and the ground elevation value is calculated, and the difference is output as the height of the target building.

8. A building elevation estimation device based on contour vector registration, characterized in that: include: A contour extraction module, used to obtain satellite images from at least two viewing angles, and extract the first building vector contour in each of the satellite images using a trained building contour extraction model; A contour pairing module, used for pairing all the first building vector contours to determine the first building vector contour corresponding to the same target building; A vector registration module is used to determine the elevation search range of the target building, and project the first building vector outlines of other images except the reference image to the object space based on each elevation value in the elevation search range, so as to obtain the second building vector outline corresponding to each of the first building vector outlines at different elevation values; The vector registration module is also used to project each of the second building vector outlines onto the reference image to obtain a third building vector outline on the reference image; A height calculation module, used for calculating the overlapping area ratio between each of the third building vector outlines and the reference building vector outline of the reference image, and determining the building elevation value of the target building based on the changing relationship between the overlapping area ratio and the corresponding elevation value; The height calculation module is also used to output the height of the target building based on the building elevation value.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the steps of the method according to any one of claims 1 to 7 are implemented.

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

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