Geometric processing method, device and equipment for satellite data spanning positive and negative 180 degrees in longitude

Abstract

The invention provides a geometric processing method, device and equipment for satellite data spanning positive and negative 180 degrees in longitude, and relates to the technical field of satellite data processing. The geometric processing method comprises the following steps: obtaining an initial longitude range corresponding to satellite data, and correcting the initial longitude range under the condition that the initial longitude range crosses positive and negative 180 degrees to obtain a corrected longitude range; performing 180-degree-crossing longitude splicing on the elevation data corresponding to the corrected longitude range to obtain spliced elevation data; establishing a space grid based on the spliced elevation data, correcting a grid point longitude value of the space grid, and establishing a rational polynomial function model according to the corrected grid point longitude value; and generating a product after geometric correction based on the rational polynomial function model and the spliced elevation data.

Description

Technical Field

[0001] The present invention relates to the field of satellite data processing technology, and in particular to a method, device, equipment and storage medium for geometrically processing satellite data whose longitude spans plus or minus 180 degrees. Background Art

[0002] Satellite data contains geometric information, enabling high-precision positioning. Existing satellite data geometric processing processes and algorithms are relatively mature for situations where the longitude range of the satellite imaging area is continuous. However, when the imaging area spans a range of ±180 degrees, existing processing processes and algorithms can lead to non-convergence of the geometric model, potentially resulting in production failures and data loss. Summary of the Invention

[0003] In view of this, the present invention provides a method, apparatus, device and storage medium for geometrically processing satellite data whose longitude spans plus or minus 180 degrees.

[0004] According to a first aspect of the present invention, a method for geometrically processing satellite data whose longitudes span plus or minus 180 degrees is provided, comprising: obtaining an initial longitude range corresponding to the satellite data; and if the initial longitude range spans plus or minus 180 degrees, correcting the initial longitude range to obtain a corrected longitude range; splicing elevation data corresponding to the corrected longitude range across 180 degrees of longitude to obtain spliced ​​elevation data; establishing a spatial grid based on the spliced ​​elevation data, correcting the longitude values ​​of grid points in the spatial grid, and establishing a rational polynomial function model based on the corrected longitude values ​​of the grid points; 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 invention, correcting the initial longitude range includes: 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, and obtaining the corrected feature point coordinates; based on the corrected feature point coordinates, recalculating the image longitude to obtain a corrected longitude range, and the longitude value of the corrected longitude range is between 0 and 360 degrees.

[0006] According to an embodiment of the present invention, the elevation data corresponding to the corrected longitude range are spliced ​​across 180 degrees of longitude to obtain the spliced ​​elevation data, including: establishing a cached longitude range of the elevation data according to the geographic range of the image, wherein the coordinate system of the cached longitude range is consistent with that 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 of the cached longitude range; subtracting 360 degrees from the longitude value greater than or equal to 180 degrees in the corrected longitude range, obtaining second elevation data corresponding to the longitude value after subtracting 360 degrees, and filling the second elevation data into the matching coordinate position in the cached longitude range; within the cached longitude range, splicing the first elevation data and the second elevation data according to the coordinate position to obtain continuous spliced ​​elevation data.

[0007] According to an embodiment of the present invention, correcting the longitude values ​​of the grid points of the spatial grid includes: increasing the negative longitude values ​​in the grid point longitude values ​​by 360 degrees, merging the correction values ​​corresponding to the original negative longitude values ​​after the increase by 360 degrees with the original positive longitude values ​​of the grid point longitude values ​​to form corrected grid point longitude values, and the corrected grid point longitude values ​​are between 0 and 360 degrees.

[0008] According to an embodiment of the present invention, obtaining the initial longitude range corresponding to the satellite data includes: obtaining auxiliary data and payload camera parameters of the satellite data, establishing a strict geometric imaging model based on the collinearity equation, and determining the initial longitude range by calculating the geographic coordinates of the four corner points and the center point of the image.

[0009] According to an embodiment of the present invention, establishing a spatial grid based on spliced ​​elevation data includes: stratifying according to the maximum and minimum values ​​in the spliced ​​elevation data at preset intervals in the elevation direction, and establishing a ground regular grid in the plane direction according to a preset grid size to obtain a spatial grid.

[0010] According to an embodiment of the present invention, generating a geometrically corrected product based on a rational polynomial function model and stitched elevation data includes: solving the rational polynomial function model to obtain rational polynomial function model parameters; obtaining a satellite primary image, and geometrically correcting the satellite primary image based on the rational polynomial function model parameters and the stitched elevation data to obtain the product.

[0011] A second aspect of the present invention provides a geometric processing device for satellite data whose longitudes span plus or minus 180 degrees, comprising: a first correction module for obtaining an initial longitude range corresponding to the satellite data, and when the initial longitude range spans plus or minus 180 degrees, correcting the initial longitude range to obtain a corrected longitude range; a splicing module for splicing elevation data corresponding to the corrected longitude range across 180 degrees of longitude to obtain spliced ​​elevation data; a second correction module for establishing a spatial grid based on the spliced ​​elevation data, correcting the longitude values ​​of the grid points of the spatial grid, and establishing a rational polynomial function model based on the corrected longitude values ​​of the grid points; and a geometric correction module for generating a geometrically corrected product based on the rational polynomial function model and the spliced ​​elevation data.

[0012] The third aspect of the present invention provides an electronic device comprising: one or more processors; a storage device for storing 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 one of the above embodiments.

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

[0014] According to the geometric processing method, apparatus, device, and storage medium for satellite data with longitudes spanning positive and negative 180 degrees, the initial longitude range is first corrected and mapped to a continuous space. This eliminates coordinate jumps at the positive and negative 180-degree boundaries, making the geometric model mathematically differentiable and convergent. Elevation data within the corrected longitude range is then spliced ​​across 180 degrees of longitude, preserving terrain details and eliminating elevation data faults. A secondary correction is then performed on the grid point longitudes, and a rational polynomial function model is constructed. Longitude values ​​exceeding positive and negative 180 degrees are wrapped to symmetrical negative values ​​that conform to the actual distribution of the geographic coordinate system, ensuring the physical consistency of the rational polynomial model. This at least partially addresses the existing problems of geometric correction image distortion, misalignment, product data loss, and production failure in the geometric processing of satellite data with longitudes spanning positive and negative 180 degrees, thereby achieving the beneficial effect of improving the quality of complex regional products in terms of coordinate accuracy and data integrity. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above contents and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0016] Figure 1 The diagram schematically shows an image of a satellite shooting area with a longitude spanning plus or minus 180 degrees;

[0017] Figure 2 Schematically illustrates a flow chart of a method for geometrically processing satellite data whose longitude spans plus or minus 180 degrees according to an embodiment of the present invention;

[0018] Figure 3 Schematically shows a flow chart of a method for geometric processing of satellite data whose longitude spans plus or minus 180 degrees according to yet another embodiment of the present invention;

[0019] Figure 4 A diagram schematically shows a comparison of geometric correction results using an existing geometric processing method and a geometric processing method according to an embodiment of the present invention;

[0020] Figure 5 A block diagram schematically illustrates a structure of a device for geometrically processing satellite data with longitudes spanning positive and negative 180 degrees according to an embodiment of the present invention;

[0021] Figure 6 The block diagram of an electronic device suitable for implementing a geometric processing method for satellite data with longitudes spanning plus or minus 180 degrees according to an embodiment of the present invention is schematically shown. DETAILED DESCRIPTION

[0022] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present invention. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of embodiments of the present invention. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of the concept of the present invention.

[0023] The terms used herein are only for describing specific embodiments and are not intended to limit the present invention. The terms "comprise," "include," etc. used herein indicate the presence of 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 meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

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

[0026] Figure 1 The diagram schematically shows an image of a satellite shooting area with a longitude spanning plus or minus 180 degrees.

[0027] like Figure 1 As shown, the dotted line is the dividing line of plus or minus 180 degrees. The left side of the coordinate longitude value can be positive, and the right side can be negative. For example, the longitude on the left side of the dividing line of plus or minus 180 degrees is 179.9999 degrees, and the longitude on the right side is -179.9999 degrees. In the prior art, if the longitude is not specially processed (the left side is close to plus 180 degrees, and the right side is close to -180 degrees) and is directly substituted into some satellite geometric positioning models for solution, it will cause the fitting to not converge, with large errors, or even failure. When using digital elevation model (DEM) data for geometric correction, incorrect DEM data will cause the geometric correction image to be distorted, misplaced, or even lose data.

[0028] In view of this, the present invention proposes a geometric processing method for satellite data whose longitude spans plus or minus 180 degrees. The geometric processing method for satellite data whose longitude spans plus or minus 180 degrees is further described below with reference to the accompanying drawings.

[0029] Figure 2 The flowchart of the method for geometrically processing satellite data whose longitude spans plus or minus 180 degrees according to one embodiment of the present invention is schematically shown.

[0030] like Figure 2 As shown, the geometric processing method for satellite data whose longitude spans plus or minus 180 degrees may include steps S210 to S240.

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

[0032] In step S220, the elevation data corresponding to the corrected longitude range is spliced ​​across 180 degrees of longitude 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 according to the corrected longitude values ​​of the grid points.

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

[0035] As an example, this embodiment can be used to process polar images covering 175 degrees east longitude to 10 degrees west longitude. After two corrections, the spliced ​​elevation eliminates the fault at the 180° line, and a continuous polar mapping product can be generated.

[0036] According to the geometric processing method for satellite data with longitudes spanning plus or minus 180 degrees of this embodiment, the initial longitude range is first corrected and mapped to a continuous space. This eliminates coordinate jumps at the plus or minus 180-degree boundary, making the geometric model mathematically differentiable and convergent. Elevation data within the corrected longitude range is then spliced ​​across 180 degrees of longitude, preserving terrain details and eliminating elevation data discontinuities. A secondary correction is then performed on the grid point longitudes, and a rational polynomial function model is constructed. Longitude values ​​exceeding plus or minus 180 degrees are wrapped to symmetrical negative values ​​that conform to the actual distribution of the geographic coordinate system, ensuring the physical consistency of the rational polynomial model. This method at least partially resolves the problems of geometric correction image distortion, misalignment, product data loss, and production failure that exist in prior art geometric processing of satellite data with longitudes spanning plus or minus 180 degrees, thereby improving the quality of complex regional products in terms of coordinate accuracy and data integrity.

[0037] Figure 3 The flowchart of the geometric processing method of satellite data with longitudes spanning plus or minus 180 degrees according to yet another embodiment of the present invention is schematically shown.

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

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

[0040] In some embodiments, correcting the initial longitude range in step S210 may 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; based on the corrected feature point coordinates, recalculating the image longitude to obtain a corrected longitude range, and the longitude value of the corrected longitude range is between 0 and 360 degrees.

[0041] For example, we can first determine whether the image spans plus or minus 180 degrees based on the longitude range, as follows:

[0042]

[0043] Among them, fabs is a function that calculates absolute values ​​and 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. Cross180 indicates whether the image spans positive or negative 180 degrees. If cross180 is 0, it means that it does not span positive or negative 180 degrees. If cross180 is 1, it means that the image spans positive or negative 180 degrees. In this case, special processing can be performed on the geometric coordinates of the five points. The negative longitude values ​​of the four corner points and the center point can be increased by 360 degrees to obtain the corrected feature point coordinates, as shown in the following formula:

[0044]

[0045] Among them, lon i ,lon i ' are the coordinate longitude values ​​before and after correction respectively. Then recalculate the longitude and latitude ranges of the image, where the longitude range is updated to [leftLon', rightLon'] and the latitude range is updated to [upLat', lowLat'].

[0046] like Figure 2 and Figure 3 As shown, step S220 can then be executed. In step S220, the elevation data corresponding to the corrected longitude range are spliced ​​across 180 degrees of longitude to obtain the spliced ​​elevation data, which may include: establishing a cached longitude range of elevation data according to the geographic range of the image, and the coordinate system of the cached longitude range is consistent with that of the corrected longitude range; obtaining the 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 cached longitude range; subtracting 360 degrees from the longitude value greater than or equal to 180 degrees in the corrected longitude range, obtaining the second elevation data corresponding to the longitude value after subtracting 360 degrees, and filling the second elevation data into the matching coordinate position in the cached longitude range; within the cached longitude range, splicing the first elevation data and the second elevation data according to the coordinate position to obtain continuous spliced ​​elevation data. It can be as follows:

[0047]

[0048] where dem （lon,lat）mosic is the elevation value at the geographical location (lon, lat) of the DEM after splicing, dem （lon,lat） It is 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, establishing a spatial grid based on the spliced ​​elevation data in step S230 can include: layering according to the maximum and minimum values ​​in the spliced ​​elevation data at a preset interval in the elevation direction, and establishing a ground regular grid according to a preset grid size in the plane direction to obtain a spatial grid.

[0050] For example, the maximum value dem can be counted based on the image DEM data range max and the minimum value dem min , in the elevation direction, layers are layered at a certain interval (e.g., k layers), and in the plane direction, a regular ground grid is established at a certain grid size (e.g., n×m grid, so that the corresponding image range has a total of (n+1)×(m+1) grid points). The number of spatial grid points is thus (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, correcting the grid point longitude value of the spatial grid in step S230 may include: increasing the negative longitude value in the grid point longitude value by 360 degrees, and merging the correction value corresponding to the original negative longitude value after the increase of 360 degrees with the original positive longitude value of the grid point longitude value to form a corrected grid point longitude value, and the corrected grid point longitude value is between 0 and 360 degrees.

[0052] For example, when converting pixel points (i, j) to geographic coordinate points (lon, lat) based on a strict geometric imaging model, if cross180 is 0, the rational polynomial coefficient (RPC) model can be directly established using the grid point geographic coordinates (lon, lat) according to existing methods. If cross180 is 1, the longitude value lon of the geographic coordinate point calculated by the strict geometric model needs to be judged. If the longitude value is negative, special processing is required and the processed lon' is substituted into the RPC model. This can be done as follows:

[0053]

[0054] like Figure 2 and Figure 3 As shown, step S240 can be finally executed. In some embodiments, the rational polynomial function model can be solved to obtain rational polynomial function model parameters; a satellite primary image is obtained, and based on the rational polynomial function model parameters and the spliced ​​elevation data, the satellite primary image is geometrically corrected to obtain a product.

[0055] For example, when solving the parameters of a rational polynomial function model, the dense ground control points generated by the strict geometric imaging model can be used as a benchmark, and the mapping relationship between image points and corresponding ground points can be fitted using the least squares method to obtain the polynomial coefficients. Subsequently, based on the strict geometric imaging model, the uncorrected primary satellite imagery can be obtained, and the mathematical mapping between image points and ground points can be constructed using the solved model parameters. Combined with the stitched elevation data, the primary imagery can be pixel-by-pixel coordinate transformed and resampled, and the imagery can be geometrically corrected from the original imaging geometry to the standard geographic coordinate system, ultimately generating a product with the required geometric accuracy.

[0056] Comparative Example

[0057] As shown in Table 1 below, an RPC model is established based on a strict satellite imaging model. In existing methods, when the satellite imaging range spans ±180 degrees, such as the grid point data at points 11, 22, and 605 in the table, without special processing, the RPC fitting error is 113774.744694 pixels in the X direction and 304.474617 pixels in the Y direction, resulting in non-convergence and unusable geometric models. As shown in Table 2, the present invention's solution, which specifically processes the geometric positioning grid points when the imaging range spans ±180 degrees, allows the RPC model to fit quickly and with high accuracy. The RPC fitting error is 0.003924 pixels in the X direction and 0.004419 pixels in the Y direction, demonstrating the superiority of the present invention.

[0058] Table 1

[0059]

[0060] Table 2

[0061]

[0062] Figure 4 A diagram schematically shows a comparison of geometric correction results using an existing geometric processing method and a geometric processing method according to an embodiment of the present invention.

[0063] When using elevation DEM data for geometric correction, existing methods can cause geometric correction image distortion and misalignment, and even lead to product data loss and production failure. Figure 4 As shown in the small figure (a) in the figure, the existing method can correctly output the correction product results for the left half with positive longitude, but loses the product for the right half with negative longitude. Figure 4 As shown in the small figure (b), the present invention performs special processing on the DEM data and obtains the correct geometric correction result, which shows the superiority of the present invention.

[0064] Based on the above-mentioned method for geometric processing of satellite data whose longitude spans plus or minus 180 degrees, the present invention also provides a device for geometric processing of satellite data whose longitude spans plus or minus 180 degrees. Figure 5 The device is described in detail.

[0065] Figure 5 The structure block diagram of the geometric processing device of satellite data with longitudes spanning plus or minus 180 degrees according to an embodiment of the present invention is schematically shown.

[0066] like Figure 5 As shown, the geometric processing device 500 for satellite data with longitudes spanning plus or minus 180 degrees in this embodiment 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. If the initial longitude range spans plus or minus 180 degrees, the initial longitude range is corrected to obtain a corrected longitude range. In one embodiment, the first correction module 510 can be used to perform the operation S210 described above, which will not be repeated here.

[0068] The splicing module 520 can be used to splice the elevation data corresponding to the corrected longitude range across 180 degrees of longitude to obtain spliced ​​elevation data. In one embodiment, the splicing module 520 can be used to perform the operation S220 described above, which will not be repeated here.

[0069] The second correction module 530 can be used to establish a spatial grid based on the spliced ​​elevation data, correct the longitude values ​​of the grid points in the spatial grid, and establish a rational polynomial function model based on the corrected longitude values ​​of the grid points. In one embodiment, the second correction module 530 can be used to perform the operation S230 described above, which will not be repeated here.

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

[0071] Please refer to the previous article for details of the relevant content, which will not be repeated here.

[0072] According to embodiments of the present invention, any multiple of the above-mentioned modules may be combined into a single module, or any one of them may be split into multiple modules. Alternatively, at least part of the functionality of one or more of these modules may be combined with at least part of the functionality of other modules and implemented in a single module. According to embodiments of the present invention, at least one of the above-mentioned modules may 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 a chip, a system on a substrate, a system on a package, an application-specific integrated circuit (ASIC), or may be implemented in hardware or firmware through any other reasonable means of circuit integration or packaging, or may be implemented in any one of the three implementation methods of software, hardware, and firmware, or in any appropriate combination of any of these. Alternatively, at least one of the above-mentioned modules may be at least partially implemented as a computer program module that, when executed, performs the corresponding functionality.

[0073] Figure 6 The block diagram of an electronic device suitable for implementing a geometric processing method for satellite data with longitudes spanning plus or minus 180 degrees according to an embodiment of the present invention is schematically shown.

[0074] like Figure 6 As shown, an electronic device 600 according to an embodiment of the present invention includes a processor 601, which can perform various appropriate actions and processes based on programs stored in a read-only memory (ROM) 602 or programs loaded from a storage unit 608 into a random access memory (RAM) 603. The processor 601 may include, for example, a general-purpose microprocessor (e.g., a CPU), an instruction set processor and / or related chipsets and / or a special-purpose microprocessor (e.g., an application-specific integrated circuit (ASIC)), etc. The processor 601 may also include onboard memory for caching purposes. The processor 601 may include a single processing unit or multiple processing units for performing different actions of the method flow according to an embodiment of the present invention.

[0075] RAM 603 stores various programs and data required for the operation of electronic device 600. Processor 601, ROM 602, and RAM 603 are interconnected via bus 604. Processor 601 executes the programs in ROM 602 and / or RAM 603 to perform various operations according to the method flow of the embodiment of the present invention. It should be noted that the programs may also be stored in one or more memories other than ROM 602 and RAM 603. Processor 601 may also execute the programs stored in one or more memories to perform various operations according to the method flow of the embodiment of the present invention.

[0076] According to an embodiment of the present invention, electronic device 600 may further include an input / output (I / O) interface 605, which is also connected to bus 604. Electronic device 600 may also include one or more of the following components connected to I / O interface 605: an input section 606 including a keyboard, mouse, etc.; an output section 607 including devices such as a cathode ray tube (CRT), liquid crystal display (LCD), and speakers; a storage section 608 including a hard disk; and a communication section 609 including a network interface card such as a LAN card or modem. Communication section 609 performs communication processing via a network such as the Internet. A drive 610 is also connected to I / O interface 605 as needed. Removable media 611, such as a magnetic disk, optical disk, magneto-optical disk, semiconductor memory, etc., is installed in drive 610 as needed, so that computer programs read from the removable media can be installed into storage section 608 as needed.

[0077] The present invention also provides a computer-readable storage medium, which may be included in the device / apparatus / system described in the above embodiments, or may exist independently and not incorporated into the device / apparatus / system. The computer-readable storage medium carries one or more programs, which, when executed, implement the method according to the embodiments of the present invention.

[0078] According to an embodiment of the present invention, a computer-readable storage medium may be a non-volatile computer-readable storage medium, and may include, for example, but not limited to: a portable computer disk, 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 disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the present invention, a computer-readable storage medium may be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. For example, according to an embodiment of the present invention, a computer-readable storage medium may include the ROM 602 and / or RAM 603 described above, and / or one or more memories other than ROM 602 and RAM 603.

[0079] Embodiments of the present invention also include a computer program product comprising a computer program containing program code for executing the method shown in the flowchart. When the computer program product is executed in a computer system, the program code causes the computer system to implement the geometric processing method for satellite data with longitudes spanning plus or minus 180 degrees, as provided in embodiments of the present invention.

[0080] The computer program executes the above functions defined in the system / device of the embodiment of the present invention when the computer program is executed by the processor 601. According to the embodiment of the present invention, the system, device, module, unit, etc. described above can be implemented by a computer program module.

[0081] In one embodiment, the computer program may be stored on a tangible storage medium such as an optical storage device or a magnetic storage device. In another embodiment, the computer program may be transmitted and distributed in the form of a signal on a network medium, downloaded and installed via the communication portion 609, and / or installed from a removable medium 611. The program code contained in the computer program may be transmitted using any appropriate network medium, including but not limited to wireless, wired, or any suitable combination thereof.

[0082] In such an embodiment, the computer program can be downloaded and installed from a network via the communication section 609 and / or installed from a removable medium 611. When the computer program is executed by the processor 601, the above-described functions defined in the system of the embodiment of the present invention are performed. According to the embodiment of the present invention, the systems, devices, means, modules, units, etc. described above can be implemented by computer program modules.

[0083] According to an embodiment of the present invention, the program code for executing the computer program provided by the embodiment of the present invention can be written in any combination of one or more programming languages. Specifically, these computer programs can be implemented using high-level procedural and / or object-oriented programming languages, and / or assembly / machine languages. Programming languages ​​include, but are not limited to, languages ​​such as Java, C++, Python, "C" or similar programming languages. The program code can be executed entirely on the user computing device, partially on the user device, partially on a remote computing device, or entirely on a remote computing device or server. In the case of a remote computing device, the remote computing device can be connected to the user computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or can be connected to an external computing device (for example, using an Internet service provider to connect via the Internet).

[0084] The flowcharts and block diagrams in the accompanying drawings illustrate the possible implementation architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present invention. In this regard, each box in the flowchart or block diagram can represent a module, program segment, or a part of code, and the above-mentioned module, program segment, or a part of code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flowchart, and the combination of boxes in the block diagram or flowchart, can be implemented with a dedicated hardware-based system that performs the specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0085] It will be understood by those skilled in the art that the features described in the various embodiments of the present invention may be combined and / or coupled in various ways, even if such combinations or couplings are not explicitly described in the present invention. In particular, the features described in the various embodiments of the present invention may be combined and / or coupled in various ways without departing from the spirit and teachings of the present invention. All such combinations and / or couplings fall within the scope of the present invention.

[0086] The above describes embodiments of the present invention. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention. Although each embodiment has been described separately above, this does not mean that the measures in each embodiment cannot be advantageously used in combination. Without departing from the scope of the present invention, those skilled in the art may make various substitutions and modifications, which should all fall within the scope of the present invention.

Claims

1. A method for geometric processing of satellite data with longitudes spanning plus or minus 180 degrees, characterized in that: include: Obtaining an initial longitude range corresponding to the satellite data, and if the initial longitude range spans plus or minus 180 degrees, correcting the initial longitude range to obtain a corrected longitude range; Splicing the elevation data corresponding to the corrected longitude range across 180 degrees of longitude to obtain spliced ​​elevation data; Establishing a spatial grid based on the spliced ​​elevation data, correcting the longitude values ​​of the grid points of the spatial grid, and establishing a rational polynomial function model according to the corrected longitude values ​​of the grid points; A geometrically corrected product is generated based on the rational polynomial function model and the spliced ​​elevation data.

2. The geometric processing method according to claim 1, characterized in that: The correcting of the initial longitude range includes: Obtaining the longitude values ​​corresponding to the four corner points and the center point in the initial longitude range, increasing the negative longitude values ​​of the four corner points and the center point by 360 degrees to obtain corrected feature point coordinates; Based on the corrected coordinates of the feature points, the image longitude is recalculated to obtain the corrected longitude range, where the longitude value of the corrected longitude range is between 0 and 360 degrees.

3. The geometric processing method according to claim 2, characterized in that: The step of splicing the elevation data corresponding to the corrected longitude range across 180 degrees of longitude to obtain spliced ​​elevation data includes: Establishing a cached longitude range for elevation data based on the geographic range of the image, wherein the cached longitude range has a coordinate system consistent with the corrected longitude range; Acquire 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 cached longitude range; Subtract 360 degrees from the longitude value greater than or equal to 180 degrees in the corrected longitude range, obtain second elevation data corresponding to the longitude value after subtracting 360 degrees, and fill the second elevation data into the matching coordinate position in the cached longitude range; Within the cache longitude range, the first elevation data and the second elevation data are spliced ​​according to coordinate positions to obtain continuous spliced ​​elevation data.

4. The geometric processing method according to claim 3, characterized in that: The correcting of the longitude values ​​of the grid points of the spatial grid includes: The negative longitude value in the grid point longitude value is increased by 360 degrees, and the correction value corresponding to the original negative longitude value after the increase of 360 degrees is merged with the original positive longitude value of the grid point longitude value to form the corrected grid point longitude value, and the corrected grid point longitude value is between 0 and 360 degrees.

5. The geometric processing method according to claim 1, characterized in that: The initial longitude range corresponding to the obtained satellite data includes: Auxiliary data and payload camera parameters of the satellite data are obtained, a strict geometric imaging model is established based on the collinearity equation, and the initial longitude range is determined by calculating the geographic coordinates of the four corner points and the center point of the image.

6. The geometric processing method according to claim 1, characterized in that: The establishing of a spatial grid based on the spliced ​​elevation data comprises: According to the maximum and minimum values ​​in the spliced ​​elevation data, stratification is performed at preset intervals in the elevation direction, and a ground regular grid is established in the plane direction according to a preset grid size to obtain the spatial grid.

7. The geometric processing method according to claim 1, characterized in that: Generating a geometrically corrected product based on the rational polynomial function model and the spliced ​​elevation data includes: Solving the rational polynomial function model to obtain rational polynomial function model parameters; A satellite primary image is obtained, and based on the rational polynomial function model parameters and the spliced ​​elevation data, the satellite primary image is geometrically corrected to obtain the product.

8. A geometric processing device for satellite data with longitudes spanning plus or minus 180 degrees, characterized in that: include: A first correction module is configured to obtain an initial longitude range corresponding to the satellite data, and to correct the initial longitude range to obtain a corrected longitude range when the initial longitude range spans plus or minus 180 degrees; A splicing module is used to splice the elevation data corresponding to the corrected longitude range across 180 degrees of longitude to obtain spliced ​​elevation data; A second correction module is used to establish a spatial grid based on the spliced ​​elevation data, correct the longitude values ​​of the grid points of the spatial grid, and establish a rational polynomial function model according to the corrected longitude values ​​of the grid points; The geometric correction module is used to generate a geometrically corrected product based on the rational polynomial function model and the spliced ​​elevation data.

9. An electronic device, characterized in that: include: one or more processors; a storage device for storing one or more programs, When the one or more programs are executed by the one or more processors, the one or more processors are enabled to perform the method according to any one of claims 1 to 7.

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

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