Geometric processing method, device and equipment for satellite data across positive and negative 180 degrees of longitude

Abstract

The present application provides a kind of longitude cross positive and negative 180 degrees satellite data geometric processing method, device and equipment, it is related to satellite data processing technical field.The geometric processing method includes: obtaining the initial longitude range corresponding to satellite data, in the case where initial longitude range crosses positive and negative 180 degrees, initial longitude range is corrected, and the modified longitude range is obtained;The elevation data corresponding to the modified longitude range is spliced across 180 degrees meridian, and the spliced elevation data is obtained;Based on the space grid of spliced elevation data, the grid point longitude value of space grid is corrected, and the rational polynomial function model is established according to the grid point longitude value after modification;Based on rational polynomial function model and spliced elevation data, generate the product after geometric correction.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of satellite data processing, and particularly relates to a longitude-crossing-180-degree satellite data geometric processing method, device, equipment and storage medium. BACKGROUND

[0002] Satellite data has geometric information and can be used for high-precision positioning. The longitude range of a satellite shooting area is continuous, and the existing satellite data geometric processing flow and algorithm are relatively mature. However, when the shooting area covers a range crossing 180 degrees, the existing processing flow and algorithm will cause the geometric model to be non-convergent, and even cause product production failure and product data loss. SUMMARY

[0003] Therefore, the present application provides a longitude-crossing-180-degree satellite data geometric processing method, device, equipment and storage medium.

[0004] According to a first aspect of the present application, a longitude-crossing-180-degree satellite data geometric processing method is provided, comprising: obtaining an initial longitude range corresponding to satellite data, in the case of the initial longitude range crossing 180 degrees, correcting the initial longitude range to obtain a corrected longitude range; performing 180-degree meridian splicing on elevation data corresponding to the corrected longitude range to obtain spliced elevation data; establishing a space grid based on the spliced elevation data, correcting the longitude value of a grid point of the space grid, and establishing a rational polynomial function model according to the corrected longitude value of the grid point; and generating a geometrically corrected product based on the rational polynomial function model and the spliced elevation data.

[0005] According to an embodiment of the present application, the correction of the initial longitude range comprises: obtaining the longitude value corresponding to the four corner points and the center point in the initial longitude range, increasing the negative longitude value in the four corner points and the center point by 360 degrees to obtain the corrected feature point coordinates; and based on the corrected feature point coordinates, re-counting the image longitude to obtain the corrected longitude range, and the longitude value of the corrected longitude range is between 0 and 360 degrees.

[0006] According to the embodiment of the present application, the elevation data corresponding to the modified longitude range is spliced across 180 meridians to obtain spliced elevation data, which comprises: establishing a buffer longitude range of the elevation data according to the image geographic range, the buffer longitude range being consistent with the coordinate system of the modified longitude range; obtaining first elevation data with longitude values less than 180 degrees in the modified longitude range, and copying the first elevation data to the same coordinate position in the buffer longitude range; subtracting 360 degrees from the longitude values greater than or equal to 180 degrees in the modified longitude range to obtain second elevation data corresponding to the longitude values after subtraction of 360 degrees, and filling the second elevation data to the matching coordinate position in the buffer longitude range; and splicing the first elevation data and the second elevation data according to the coordinate position in the buffer longitude range to obtain continuous spliced elevation data.

[0007] According to the embodiment of the present application, the longitude value of the grid point of the spatial grid is modified, which comprises: increasing the negative longitude value in the longitude value of the grid point by 360 degrees, and combining the corresponding modified value of the original negative longitude value after the increase of 360 degrees with the original positive longitude value of the longitude value of the grid point to form the modified longitude value of the grid point, the modified longitude value of the grid point being between 0 and 360 degrees.

[0008] According to the embodiment of the present application, the initial longitude range corresponding to the satellite data is obtained, which comprises: obtaining auxiliary data and load camera parameters of the satellite data, establishing a strict geometric imaging model based on a collinear equation, and determining the initial longitude range by calculating the geographic coordinates of the image four-corner points and the center point.

[0009] According to the embodiment of the present application, the spatial grid is established based on the spliced elevation data, which comprises: layering in the elevation direction according to a preset interval based on the maximum value and the minimum value in the spliced elevation data, and establishing a regular ground grid in the plane direction according to a preset grid size to obtain the spatial grid.

[0010] According to the embodiment of the present application, the product after geometric correction is generated based on the rational polynomial function model and the spliced elevation data, which comprises: solving the rational polynomial function model to obtain rational polynomial function model parameters; obtaining satellite primary images, and performing geometric correction on the satellite primary images based on the rational polynomial function model parameters and the spliced elevation data to obtain the product.

[0011] The second aspect of the present application provides a longitude-crossing-180-degree satellite data geometric processing device, comprising: a first correction module configured to obtain an initial longitude range corresponding to satellite data, and correct the initial longitude range to obtain a corrected longitude range when the initial longitude range crosses positive and negative 180 degrees; a splicing module configured to splice elevation data corresponding to the corrected longitude range across 180-degree meridians to obtain spliced elevation data; a second correction module configured to establish a spatial grid based on the spliced elevation data, correct longitude values of grid points of the spatial grid, and establish a rational polynomial function model according to the corrected longitude values of the grid points; and a geometric correction module configured to generate a geometrically corrected product based on the rational polynomial function model and the spliced elevation data.

[0012] The third aspect of the present application provides an electronic device, comprising: one or more processors; a storage device configured to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors execute the method in any of the above embodiments.

[0013] The fourth aspect of the present application provides a computer-readable storage medium having stored thereon a computer program or instructions, which, when executed by a processor, implement the steps of the method in any of the above embodiments.

[0014] The longitude-crossing-180-degree satellite data geometric processing method, device, equipment and storage medium according to the embodiments of the present application first correct the initial longitude range, map the initial longitude range to a continuous space, can eliminate the coordinate jump of the positive and negative 180-degree boundary, make the geometric model mathematically derivable and convergent, then splice the elevation data of the corrected longitude range across 180-degree meridians, can retain the terrain details and eliminate the elevation data faults, then secondarily correct the longitude of the grid points and construct a rational polynomial function model, rewind the longitude values exceeding positive and negative 180 degrees to symmetric negative values, consistent with the actual distribution of the geographic coordinate system, ensure the physical significance consistency of the rational polynomial model, thereby at least partially solve the problems of geometric correction image distortion, misplacement, product data loss and production failure in the geometric processing of longitude-crossing-180-degree satellite data in the prior art, achieve the beneficial effect of improving the quality of the complex area product in terms of coordinate accuracy, data integrity and the like. BRIEF DESCRIPTION OF DRAWINGS

[0015] The above and other objects, features and advantages of the present application will become more apparent from the following description of embodiments of the present application taken in conjunction with the accompanying drawings, in which:

[0016] Figure 1 An imaging diagram schematically showing that the longitude of a satellite shooting area crosses positive and negative 180 degrees;

[0017] Figure 2 Fig. 4 is a flow chart illustrating a method of geometric processing of satellite data with longitude spanning over plus and minus 180 degrees according to an embodiment of the present application;

[0018] Figure 3 Fig. 5 is a flow chart illustrating a method of geometric processing of satellite data with longitude spanning over plus and minus 180 degrees according to another embodiment of the present application;

[0019] Figure 4 Fig. 6 is a comparison chart of geometric correction results of the existing geometric processing method and the geometric processing method according to an embodiment of the present application;

[0020] Figure 5 Fig. 7 is a block diagram illustrating a structure of a geometric processing device for satellite data with longitude spanning over plus and minus 180 degrees according to an embodiment of the present application;

[0021] Figure 6 Fig. 8 is a block diagram illustrating an electronic device suitable for implementing a method of geometric processing of satellite data with longitude spanning over plus and minus 180 degrees according to an embodiment of the present application. DETAILED DESCRIPTION

[0022] Hereinafter, embodiments of the present application will be described with reference to the accompanying drawings. It should be understood, however, that the description which follows is merely illustrative and is not intended to limit the scope of the present application. In the following detailed description of embodiments of the present application, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, it will be apparent to one skilled in the art that one or more embodiments of the present application can be practiced without these specific details. In other instances, well-known structures and functions have not been described in detail in order to avoid obscuring aspects of the present application.

[0023] The terms used herein are merely used to describe specific embodiments and are not intended to limit the present application. The terms "include", "comprise", and the like used herein indicate the presence of the features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0024] All terms used herein, including technical and scientific terms, have the same meanings as those generally understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having meanings consistent with the context of the present specification, and should not be interpreted in an idealized or overly formal manner.

[0025] When using expressions such as "at least one of A, B and C", they should generally be interpreted in accordance with the meaning that is commonly understood by those skilled in the art (e.g., "a system having at least one of A, B and C" should include, but is not limited to, a system having A alone, a system having B alone, a system having C alone, a system having A and B, a system having A and C, a system having B and C, and / or a system having A, B and C, etc.).

[0026] Figure 1 The image schematically illustrates the longitude spanning plus or minus 180 degrees of the satellite-captured area.

[0027] like Figure 1 As shown, the dashed line represents the 180-degree boundary. Longitude values ​​can be positive to the left and negative to the right. For example, the longitude to the left of the 180-degree boundary is 179.9999 degrees, and the longitude to the right is -179.9999 degrees. In existing technologies, directly substituting the longitude values ​​into satellite geometric positioning models without special processing (approximately +180 degrees to the left and -180 degrees to the right) can lead to non-convergence of the fit, large errors, and even failure. When using Digital Elevation Model (DEM) data for geometric correction, incorrect DEM data can cause distortion, misalignment, or even data loss in the geometrically corrected image.

[0028] In view of this, the present invention proposes a geometric processing method for satellite data with longitude spanning ±180 degrees. The following description, in conjunction with the accompanying drawings, further illustrates the geometric processing method for satellite data with longitude spanning ±180 degrees.

[0029] Figure 2 A flowchart illustrating a method for geometric processing of satellite data spanning plus or minus 180 degrees of longitude according to an embodiment of the present invention is shown.

[0030] like Figure 2 As shown, the geometric processing method for satellite data with longitude spanning ±180 degrees may include steps S210 to S240.

[0031] In step S210, the initial longitude range corresponding to the satellite data is obtained. If the initial longitude range spans ±180 degrees, the initial longitude range is corrected to obtain the corrected longitude range.

[0032] In step S220, the elevation data corresponding to the corrected longitude range are spliced ​​across 180-degree meridians to obtain spliced ​​elevation data.

[0033] In step S230, a spatial grid is established based on the spliced ​​elevation data, the longitude values ​​of the grid points of the spatial grid are corrected, and a rational polynomial function model is established based on the corrected longitude values ​​of the grid points.

[0034] At step S240, a geometrically corrected product is generated based on the rational polynomial function model and the stitched elevation data.

[0035] As an example, polar images covering 175 degrees east longitude to 10 degrees west longitude can be processed by the present embodiment, after two corrections, the stitching elevation eliminates the fault at 180° line, and a continuous polar mapping product can be generated.

[0036] According to the geometric processing method of satellite data with longitude spanning positive and negative 180 degrees, the initial longitude range is first corrected, and the initial longitude range is mapped to a continuous space, which can eliminate the coordinate jump of the positive and negative 180-degree boundary, and make the geometric model mathematically derivable and convergent. Then, the elevation data of the corrected longitude range is stitched across the 180-degree meridian, which can preserve the terrain details and eliminate the elevation data fault. Then, the longitude of the grid point is corrected twice and a rational polynomial function model is constructed, which can wrap the longitude values exceeding positive and negative 180 degrees to symmetric negative values, which conforms to the actual distribution of the geographic coordinate system and ensures the physical significance consistency of the rational polynomial model, thereby at least partially solving the problems of geometric correction image distortion, misplacement, product data loss and production failure in the geometric processing of satellite data with longitude spanning positive and negative 180 degrees in the prior art, and achieving the beneficial effect of improving the quality of the product in the coordinate precision, data integrity and other aspects in the complex region.

[0037] Figure 3 A flowchart of a geometric processing method of satellite data with longitude spanning positive and negative 180 degrees according to another embodiment of the present application is schematically shown.

[0038] As Figure 2 and Figure 3 shown, step S210 can be first performed. In some embodiments, step S210 of obtaining the initial longitude range corresponding to the satellite data can include: obtaining auxiliary data and payload camera parameters of the satellite data, establishing a strict geometric imaging model based on a collinearity equation, and determining the initial longitude range by calculating the geographic coordinates of the image quadrilateral points and the center points.

[0039] For example, satellite orbit parameters (such as ephemeris data, attitude angle), camera interior orientation elements (such as principal point coordinates, focal length) and exterior orientation elements (such as position, attitude) can be obtained as collinear equation inputs. A strict geometric imaging model can be constructed based on the collinear equation to correlate the image point (x, y) and the ground point (X, Y, Z) through the projection center to form a mathematical expression of the object-image relationship. According to the image length M pixels and the width N pixels, the pixel coordinates of the four corner points and the center point in the image coordinate system can be obtained, which are respectively denoted as [0, 0], [N-1, 0], [N-1, M-1], [0, M-1], [M / 2, N / 2]. Based on the strict imaging model, the geometric geographic coordinates corresponding to the five points are calculated, and the image longitude and latitude ranges are counted, wherein the longitude range can be represented as [leftLon, rightLon], and the latitude range can be represented as [upLat, lowLat].

[0040] In some embodiments, the correction of the initial longitude range in step S210 can include: obtaining the longitude values corresponding to the four corner points and the center point in the initial longitude range, increasing the negative longitude values in the four corner points and the center point by 360 degrees to obtain the corrected feature point coordinates; and based on the corrected feature point coordinates, re-counting the image longitude to obtain a corrected longitude range, the longitude values of the corrected longitude range being between 0 and 360 degrees.

[0041] For example, whether the image crosses the positive and negative 180 degrees can be determined according to the longitude range, which can be as follows:

[0042]

[0043] wherein fabs is a function for calculating the absolute value, which can be used to obtain the absolute value of a number, leftLon and rightLon are the longitude values of the left corner point and the right corner point respectively, and cross180 represents the determination result of whether the image crosses the positive and negative 180 degrees. If cross180 is 0, it means that the image does not cross the positive and negative 180 degrees, and if cross180 is 1, it means that the image crosses the positive and negative 180 degrees, in which case the geometric geographic coordinates of the five points can be specially processed. The negative longitude values in the four corner points and the center point can be increased by 360 degrees to obtain the corrected feature point coordinates, which can be as follows:

[0044]

[0045] wherein lon i and lon i are the coordinate longitude values before and after correction respectively. Then the image longitude and latitude ranges are re-counted, wherein the longitude range is updated as [leftLon’, rightLon’], and the latitude range is updated as [upLat’, lowLat’].

[0046] For example,Figure 2 and Figure 3 As shown, step S220 can then be executed. Step S220 involves stitching the elevation data corresponding to the corrected longitude range across 180-degree meridians to obtain stitched elevation data. This may include: establishing a cached longitude range for elevation data based on the image's geographical extent, with the cached longitude range having the same coordinate system as the corrected longitude range; obtaining the first elevation data with longitude values ​​less than 180 degrees in the corrected longitude range and copying it to the same coordinate position in the cached longitude range; subtracting 360 degrees from the longitude values ​​greater than or equal to 180 degrees in the corrected longitude range to obtain the second elevation data corresponding to the subtracted longitude values, and filling the second elevation data into the matching coordinate position in the cached longitude range; within the cached longitude range, stitching the first and second elevation data according to their coordinate positions to obtain continuous stitched elevation data. This can be expressed as follows:

[0047]

[0048] Among them, dem （lon,lat）mosic The elevation value at the geographic location (lon,lat) of the stitched DEM is the elevation value. （lon,lat） This represents the elevation value at the global DEM geographic location (lon,lat).

[0049] like Figure 2 and Figure 3 As shown, step S230 can then be executed. In some embodiments, step S230, which involves establishing a spatial grid based on the stitched elevation data, may include: layering the data in the elevation direction according to a preset interval based on the maximum and minimum values ​​within the stitched elevation data, and establishing a ground regular grid in the planar direction according to a preset grid size, thereby obtaining a spatial grid.

[0050] For example, the maximum value of dem can be calculated based on the range of image DEM data. max and minimum value dem min In the elevation direction, layers are created at certain intervals (e.g., k layers). In the horizontal direction, a regular ground grid is established according to a certain grid size (e.g., an n×m grid, so the corresponding image range has (n+1)×(m+1) grid points). Thus, the number of spatial grid points is (n+1)×(m+1)×k. The preset interval and preset grid size can be set according to the resolution of the satellite data and the image range.

[0051] In some embodiments, the correction of the longitude value of the grid point in step S230 may include: increasing the negative longitude value of the grid point by 360 degrees, merging the correction value corresponding to the original negative longitude value after increasing by 360 degrees with the original positive longitude value of the grid point to form the corrected grid point longitude value, wherein the corrected grid point longitude value is between 0 and 360 degrees.

[0052] For example, based on the strict geometric imaging model, the conversion of the pixel point (i, j) to the geographic coordinate point (lon, lat) can be directly established by using the grid point geographic coordinates (lon, lat) to establish the RPC model according to the existing method if cross180 is 0; if cross180 is 1, the longitude value lon calculated by the strict geometric model needs to be judged, and if the longitude value is negative, special processing needs to be performed, and the processed lon' is substituted into the RPC model to establish the RPC model. The following formula can be used:

[0053]

[0054] As shown in FIGS. 1, 2 and 3, finally, step S240 can be performed. In some embodiments, the rational polynomial function model can be solved to obtain the rational polynomial function model parameters; the satellite primary image is obtained, and the satellite primary image is geometrically corrected based on the rational polynomial function model parameters and the spliced elevation data to obtain a product. Figure 2 Figure 3 For example, when the rational polynomial function model parameters are solved, the dense ground control points generated by the strict geometric imaging model can be taken as a reference, and the mapping relationship between the image points and the corresponding ground points is fitted by the least square method to obtain the polynomial coefficients. Subsequently, based on the strict geometric imaging model, the satellite primary image without geometric correction can be obtained, the mathematical mapping between the image points and the ground points is constructed by using the solved model parameters, the coordinate conversion and resampling of the primary image are performed pixel by pixel in combination with the spliced elevation data, the image is corrected from the original imaging geometry to the standard geographic coordinate system, and finally the product with the required geometric accuracy is generated.

[0055] For example, when the rational polynomial function model parameters are solved, the dense ground control points generated by the strict geometric imaging model can be taken as a reference, and the mapping relationship between the image points and the corresponding ground points is fitted by the least square method to obtain the polynomial coefficients. Subsequently, based on the strict geometric imaging model, the satellite primary image without geometric correction can be obtained, the mathematical mapping between the image points and the ground points is constructed by using the solved model parameters, the coordinate conversion and resampling of the primary image are performed pixel by pixel in combination with the spliced elevation data, the image is corrected from the original imaging geometry to the standard geographic coordinate system, and finally the product with the required geometric accuracy is generated.

[0056] Comparative example

[0057] As shown in Table 1, the RPC model is established based on the satellite strict imaging model, and the RPC fitting error is 113774.744694 pixels in the X direction and 304.474617 pixels in the Y direction if the satellite shooting range crosses the positive and negative 180 degrees, such as the grid point data in numbers 11, 22 and 605 in the table, without special processing. The geometric model does not converge and cannot be used. As shown in Table 2, the present application scheme performs special processing on the geometric positioning grid point when the shooting range crosses the positive and negative 180 degrees, the RPC model is quickly fitted, and the fitting accuracy is very high, the RPC fitting error is 0.003924 pixels in the X direction and 0.004419 pixels in the Y direction. The superiority of the present application can be seen.

[0058] Table 1​

[0059]

[0060] Table 2

[0061]

[0062] Figure 4 A comparison diagram of geometric correction results of the geometric processing method of the prior art and the embodiment of the present application is schematically shown.

[0063] When the geometric correction is performed by using the elevation DEM data, the prior method can cause the geometric correction image to be distorted, misaligned, and even cause the product to lose data and fail to be produced. As shown in the (a) sub-diagram of FIG. 1, Figure 4 As shown in the (b) sub-diagram of FIG. 1, Figure 4 The present application performs special processing on the DEM data, and obtains the correct geometric correction result, which can show the superiority of the present application.

[0064] Based on the above geometric processing method of the satellite data with the longitude crossing the positive and negative 180 degrees, the present application further provides a geometric processing device of the satellite data with the longitude crossing the positive and negative 180 degrees. Figure 5 The device will be described in detail below.

[0065] Figure 5 A structure block diagram of the geometric processing device of the satellite data with the longitude crossing the positive and negative 180 degrees according to the embodiment of the present application is schematically shown.

[0066] As shown in FIG. 5, Figure 5 The geometric processing device 500 of the satellite data with the longitude crossing the positive and negative 180 degrees according to the embodiment of the present application includes a first correction module 510, a splicing module 520, a second correction module 530, and a geometric correction module 540.

[0067] The first correction module 510 can be used to obtain an initial longitude range corresponding to the satellite data, and correct the initial longitude range to obtain a corrected longitude range in the case that the initial longitude range crosses the positive and negative 180 degrees. In an embodiment, the first correction module 510 can be used to perform the operation S210 described above, and details are not described herein.

[0068] The splicing module 520 can be used to splice the elevation data corresponding to the corrected longitude range across the 180-degree meridian to obtain spliced elevation data. In an embodiment, the splicing module 520 can be used to perform the operation S220 described above, and details are not described herein.

[0069] The second correction module 530 can be configured to establish a spatial grid based on the spliced elevation data, correct the longitude value of a grid point of the spatial grid, and establish a rational polynomial function model according to the corrected longitude value of the grid point. In an embodiment, the second correction module 530 can be configured to perform the operation S230 described above, and details are not repeated here.

[0070] The geometric correction module 540 can be configured to generate a geometrically corrected product based on the rational polynomial function model and the spliced elevation data. In an embodiment, the geometric correction module 540 can be configured to perform the operation S240 described above, and details are not repeated here.

[0071] Details of related content are described above, and details are not repeated here.

[0072] According to embodiments of the present application, any of the above modules can be combined in one module, or any of the modules can be split into multiple modules. Alternatively, at least part of the function of one or more of the modules can be combined with at least part of the function of another module, and implemented in one module. According to embodiments of the present application, at least one of the above modules can be at least partially implemented as a hardware circuit, such as a field programmable gate array (FPGA), a programmable logic array (PLA), a system on chip, a system on board, a system on package, an application specific integrated circuit (ASIC), or any other reasonable way of hardware or firmware by integrating or packaging the circuit, or implemented in any one of software, hardware and firmware or in a proper combination of any of them. Alternatively, at least one of the above modules can be at least partially implemented as a computer program module which can perform corresponding functions when the computer program module is run.

[0073] Figure 6 A block diagram of an electronic device suitable for implementing the method for geometric processing of satellite data with longitude crossing over 180 degrees according to embodiments of the present application is schematically shown.

[0074] As shown in FIG. 6, the electronic device 600 according to embodiments of the present application includes a processor 601 which can perform various appropriate actions and processes according to programs stored in a read-only memory (ROM) 602 or loaded from a storage portion 608 to a random access memory (RAM) 603. The processor 601 can include, for example, a general-purpose microprocessor (such as a CPU), an instruction set processor, and / or a related chipset, and / or a special-purpose microprocessor (such as an application specific integrated circuit (ASIC)), and the like. The processor 601 can also include an on-board memory for cache use. The processor 601 can include a single processing unit or multiple processing units for performing different actions of the method processes according to embodiments of the present application. Figure 6 As shown in FIG. 6, the electronic device 600 according to embodiments of the present application includes a processor 601 which can perform various appropriate actions and processes according to programs stored in a read-only memory (ROM) 602 or loaded from a storage portion 608 to a random access memory (RAM) 603. The processor 601 can include, for example, a general-purpose microprocessor (such as a CPU), an instruction set processor, and / or a related chipset, and / or a special-purpose microprocessor (such as an application specific integrated circuit (ASIC)), and the like. The processor 601 can also include an on-board memory for cache use. The processor 601 can include a single processing unit or multiple processing units for performing different actions of the method processes according to embodiments of the present application.

[0075] In the RAM 603, various programs and data required for the operation of the electronic device 600 are stored. The processor 601, the ROM 602, and the RAM 603 are connected to each other via the bus 604. The processor 601 performs various operations of the method flow according to the embodiments of the present application by executing the programs in the ROM 602 and / or the RAM 603. It should be noted that the programs can also be stored in one or more memories other than the ROM 602 and the RAM 603. The processor 601 can also perform various operations of the method flow according to the embodiments of the present application by executing the programs stored in the one or more memories.

[0076] According to the embodiments of the present application, the electronic device 600 can further include an input / output (I / O) interface 605, which is also connected to the bus 604. The electronic device 600 can further include one or more of the following components connected to the input / output (I / O) interface 605: an input part 606 including a keyboard, a mouse, etc.; an output part 607 including a cathode ray tube (CRT), a liquid crystal display (LCD), etc., and a speaker, etc.; a storage part 608 including a hard disk, etc.; and a communication part 609 including a network interface card such as a LAN card, a modem, etc. The communication part 609 performs communication processing via a network such as the Internet. A drive 610 is also connected to the input / output (I / O) interface 605 as necessary. A removable medium 611 such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc. is mounted on the drive 610 as necessary, so that a computer program read out therefrom is installed in the storage part 608 as necessary.

[0077] The present application also provides a computer readable storage medium, which can be included in the device / apparatus / system described in the above embodiments; or can exist separately without being assembled into the device / apparatus / system. The above computer readable storage medium carries one or more programs, when the one or more programs are executed, the method according to the embodiments of the present application is implemented.

[0078] According to an embodiment of the present application, the computer readable storage medium can be a non-transitory computer readable storage medium, for example, can include but not limited to: a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the present application, the computer readable storage medium can be any tangible medium that contains or stores a program that can be used by or in connection with an instruction execution system, apparatus, or device. For example, according to an embodiment of the present application, the computer readable storage medium can include one or more memories of the ROM 602 and / or the RAM 603 described above and / or one or more memories other than the ROM 602 and the RAM 603.

[0079] Embodiments of the present application also include a computer program product, which includes a computer program containing program codes for executing the methods shown in the flowcharts. When the computer program product is run in a computer system, the program codes are used to make the computer system implement the method for geometric processing of satellite data with longitude crossing positive and negative 180 degrees provided by the embodiments of the present application.

[0080] The above functions defined in the system / device of the embodiments of the present application are performed when the computer program is executed by the processor 601. According to an embodiment of the present application, the system, device, module, unit, etc. described above can be implemented by computer program modules.

[0081] In one embodiment, the computer program can rely on tangible storage media such as optical storage media, magnetic storage media, etc. In another embodiment, the computer program can also be transmitted, distributed, and downloaded in the form of signals on network media, and be downloaded and installed through the communication part 609, and / or installed from the detachable medium 611. The program codes contained in the computer program can be transmitted by any suitable network media, including but not limited to: wireless, wired, etc., or any suitable combination of the foregoing.

[0082] In such an embodiment, the computer program can be downloaded and installed from the network through the communication part 609, and / or installed from the detachable medium 611. When the computer program is executed by the processor 601, the above functions defined in the system of the embodiments of the present application are performed. According to an embodiment of the present application, the system, device, apparatus, module, unit, etc. described above can be implemented by computer program modules.

[0083] According to embodiments of the present application, program code for implementing the computer programs provided by embodiments of the present application can be written in any combination of one or more programming languages, and can be implemented using high-level procedural and / or object-oriented programming languages, and / or assembly / machine languages. The programming language can include, but is not limited to, Java, C++, python, "C" language, or similar programming languages. The program code can execute entirely on the user's computing device, partly on the user's device, as a stand-alone software package, partly on the remote computing device, or entirely on the remote computing device or server. In the latter scenario, the remote computing device can be connected to the user's computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computing device, such as through the Internet using an Internet Service Provider.

[0084] The computer program instructions can also be loaded onto a computer or other programmable information processing apparatus to cause a series of operations to be performed on the computer or other programmable information processing apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable information processing apparatus implement the functions / acts specified in the flowchart and / or block diagram block or blocks.

[0085] Those skilled in the art will appreciate that the features recited in the various embodiments of the present application can be combined and / or integrated in a variety of ways, even if such combinations or integrations are not expressly noted in the present application. In particular, the features recited in the various embodiments of the present application can be combined and / or integrated in a variety of ways without departing from the spirit and scope of the present application. All such combinations and / or integrations are within the scope of the present application.

[0086] The embodiments of the present application have been described above. However, these embodiments are merely for the purpose of illustration and are not intended to limit the scope of the present application. Although the respective embodiments are described above separately, this does not mean that the measures in the respective embodiments cannot be used advantageously in combination. Numerous alternatives and modifications of embodiments of the present application can be made by those skilled in the art without departing from the scope of the present application, and all such alternatives and modifications are to be included within the scope of the present application.

Claims

1. A method for geometric processing of satellite data spanning a longitude of plus or minus 180 degrees, characterized by, The method comprises the following steps: obtaining an initial longitude range corresponding to satellite data, and correcting the initial longitude range to obtain a corrected longitude range in the case that the initial longitude range crosses positive and negative 180 degrees; splicing elevation data corresponding to the corrected longitude range across 180-degree meridians to obtain spliced elevation data; the method comprises the following steps: establishing a buffered longitude range of the elevation data according to an image geographical range, wherein the buffered longitude range is consistent with the coordinate system of the corrected longitude range; obtaining first elevation data with a longitude value less than 180 degrees in the corrected longitude range, and copying the first elevation data to the same coordinate position in the buffered longitude range; subtracting 360 degrees from the longitude value greater than or equal to 180 degrees in the corrected longitude range to obtain second elevation data corresponding to the longitude value after the subtraction of 360 degrees, and filling the second elevation data into the matching coordinate position in the buffered longitude range; and splicing the first elevation data and the second elevation data according to the coordinate position in the buffered longitude range to obtain continuous spliced elevation data; establishing a spatial grid based on the spliced elevation data, correcting the longitude value of a grid point of the spatial grid, and establishing a rational polynomial function model according to the corrected longitude value of the grid point; generating a geometrically corrected product based on the rational polynomial function model and the spliced elevation data.

2. The method of claim 1, wherein, The correction of the initial longitude range comprises the following steps: obtaining the longitude value corresponding to a four-corner point and a center point in the initial longitude range, increasing 360 degrees to the negative longitude value in the four-corner point and the center point to obtain the coordinates of the corrected feature points; recounting the image longitude based on the coordinates of the corrected feature points to obtain the corrected longitude range, wherein the longitude value of the corrected longitude range is between 0 and 360 degrees.

3. The method of claim 1, wherein, The correction of the longitude value of the grid point of the spatial grid comprises the following steps: increasing 360 degrees to the negative longitude value in the longitude value of the grid point, combining the correction value of the original negative longitude value after the increase of 360 degrees with the original positive longitude value of the longitude value of the grid point to form the corrected longitude value of the grid point, and the corrected longitude value of the grid point is between 0 and 360 degrees.

4. The method of claim 1, wherein, The obtaining of the initial longitude range corresponding to the satellite data comprises the following steps: obtaining auxiliary data and load camera parameters of the satellite data, establishing a strict geometric imaging model based on a collineation equation, and determining the initial longitude range by calculating the geographical coordinates of image four-corner points and center points.

5. The method of claim 1, wherein, The establishment of the spatial grid based on the spliced elevation data comprises the following steps: layering in the elevation direction according to a preset interval and establishing a ground regular grid in the plane direction according to a preset grid size based on the maximum value and the minimum value in the spliced elevation data to obtain the spatial grid.

6. The method of claim 1, wherein, The generation of the geometrically corrected product based on the rational polynomial function model and the spliced elevation data comprises the following steps: solving the rational polynomial function model to obtain rational polynomial function model parameters; obtaining satellite primary images, geometrically correcting the satellite primary images based on the rational polynomial function model parameters and the spliced elevation data to obtain the product.

7. A device for geometric processing of satellite data spanning a longitude of plus or minus 180 degrees, characterized by The method comprises the following steps: The first correction module is configured to obtain an initial longitude range corresponding to satellite data, and correct the initial longitude range to obtain a corrected longitude range when the initial longitude range spans positive and negative 180 degrees. The splicing module is configured to splice elevation data corresponding to the corrected longitude range across 180-degree meridians to obtain spliced elevation data. The splicing module is further configured to establish a cache longitude range of the elevation data according to an image geographic range, the cache longitude range being consistent with a coordinate system of the corrected longitude range. The splicing module is further configured to obtain first elevation data with a longitude value less than 180 degrees in the corrected longitude range, and copy the first elevation data to the same coordinate position in the cache longitude range. The splicing module is further configured to subtract 360 degrees from the longitude value greater than or equal to 180 degrees in the corrected longitude range to obtain second elevation data corresponding to the longitude value after the subtraction, and fill the second elevation data into the matching coordinate position in the cache longitude range. The splicing module is further configured to splice the first elevation data and the second elevation data according to the coordinate position in the cache longitude range to obtain continuous spliced elevation data. The second correction module is configured to establish a spatial grid based on the spliced elevation data, correct the longitude value of a grid point of the spatial grid, and establish a rational polynomial function model according to the corrected longitude value of the grid point. The geometric correction module is configured to generate a geometrically corrected product based on the rational polynomial function model and the spliced elevation data.

8. An electronic device, comprising: The computer program or instructions are executed by the processor to implement the steps of the method according to any one of claims 1 to 6. The computer program or instructions are executed by the processor to implement the steps of the method according to any one of claims 1 to 6. ​ ​ 9. A computer readable storage medium having stored thereon a computer program or instructions, characterized in that, ​

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