A method and device for extracting points of interest

Abstract

The present invention belongs to the technical field of GIS data processing. The present invention discloses a method and device for extracting points of interest. By establishing a vector surface of a target area, a first set of points of interest and a second set of points of interest are obtained after coordinate transformation. Through processes such as fusing and removing duplicates between the two, the target points of interest are obtained. After converting the coordinates of Internet points of interest resources to the coordinate system required by users and fusing them with municipal survey data, GIS workers can obtain the required points of interest resources conveniently and quickly in batches. At the same time, the Internet online map obtains municipal data, so that to a certain extent, traditional map resources and Internet map resources can complement each other's advantages. By comparing and calculating the standard pixel values of ground objects with the standard remote sensing image database, the required points of interest can be directly obtained from remote sensing images, expanding the breadth and depth of the data sources of points of interest.

Description

Technical Field

[0001] The present invention relates to the technical field of geographic information system data processing, and in particular, to a method and device for extracting points of interest. Background Art

[0002] In the current surveying and mapping and geographic information industries, map data generally refers to data maps. Common paper version maps, remote sensing images, etc. can all be referred to as map data. Map data stored in various media in electronic form is also called electronic maps. The surveying and mapping and geographic information industries divide electronic maps into vector maps and non-vector maps. Vector maps contain various coordinate data. Common vector maps in daily life include Internet maps such as Baidu Map and Gaode Map. There is a large amount of point-of-interest information in common Internet maps. Since most of the point-of-interest data is obtained based on Internet technology or manually uploaded automatically, in this case, the accuracy of the points of interest is relatively low. In places with less traffic, the density of points of interest is insufficient. Each Internet map has its own independent coordinate system. Common local survey and design institutes have their own independently surveyed electronic maps. This kind of map data has high precision and high data accuracy, but usually adopts the method of manual measurement for on-demand collection, and this method has a large amount of labor.

[0003] How to balance the integration between multi-source data, and then be able to obtain the required point-of-interest data quickly, in batches, with low cost and high efficiency is a problem worthy of research by GIS workers. Summary of the Invention

[0004] In view of the deficiencies of the prior art, the present invention provides a method and device for extracting points of interest.

[0005] The present invention solves the above technical problems through the following technical means: A method for extracting points of interest, comprising:

[0006] A method for extracting points of interest, comprising the following steps:

[0007] S1. Obtain a first target area vector surface, and the coordinates of the first target area vector surface are in the first coordinate system;

[0008] S2. Superimpose the first map and the first target area vector surface to obtain a first map point-of-interest set. The coordinates of the first map are in the first coordinate system. The first map point-of-interest set is composed of at least one point of interest. The point of interest includes an association table, and the association table includes the corresponding point-of-interest coordinate system and point-of-interest name;

[0009] S3. Intersect the electronic map road network data with the first target area vector surface to obtain the target area electronic map road network data. The coordinates of the area electronic map road network data are in the second coordinate system;

[0010] The electronic map road network data includes the target area electronic map road network data and the electronic map surface data. The road network data includes road width, road name data, and coordinate data. The electronic map surface data includes electronic map surface name data and coordinate data;

[0011] Among them, if the coordinate system of the first target area vector surface element is inconsistent with the second coordinate system of the electronic map road network data, the coordinates of the first target area vector surface are converted to the second coordinate system;

[0012] S4. Convert the target area electronic map road network data into a line feature set, and intersect the line feature set with the target area electronic map surface data set to obtain a second set of interest points; the coordinates of the second set of interest points are the second coordinates;

[0013] S5. Set a radius with the first set of interest points as the center to construct a first set of interest surfaces, superimpose the second set of interest points on the first set of interest surfaces, and remove the first set of interest points in the second set of interest points that fall within the first set of interest surfaces to obtain a third set of interest points;

[0014] If the first coordinate system of the first set of interest points is inconsistent with the coordinate system of the second set of interest points, convert the first coordinate system of the first set of interest points to the second coordinate system.

[0015] S6. Integrate the first set of interest points and the third set of interest points to obtain the target set of interest points.

[0016] Preferably, the superimposing process in S2 is as follows:

[0017] S21. Obtain the coordinate information P1 of the first set of interest points i (X i , Y i ) and the point coordinate information P2 of the first target area vector surface j (X j , Y j );

[0018] S22. Take the difference between the coordinates of P1 i and P2 j . When the following formula is satisfied, the process of retaining the difference value of the first set of interest points is calculated using the following formula:

[0019]

[0020] Among them, P1 i (X i , Y i ) represents the coordinates of the i-th point of the first set of interest points, and X i represents the X coordinate method of the i-th point of the first set of interest points, and Yi The Y method coordinate of the i-th point in the first set of points of interest, P2 j (X j , Y j ) represents the coordinates of the j-th point in the first target area vector surface, X j represents the X method coordinate value of the j-th point in the first target area vector surface, Y j represents the coordinate of the j-th point in the first target area vector surface in the Y method.

[0021] Preferably, the coordinate conversion method adopts a four-parameter model, and the specific model is as follows:

[0022]

[0023] Among them, in the above formula, , represents the coordinate in the Q coordinate system, , represents the coordinate in the G coordinate system, , , , are the coordinate conversion parameters for converting the G coordinate system to the Q coordinate system, , are the translation parameters between the two coordinates, represents the scaling parameter between the two coordinate systems, represents the rotation parameter between the two coordinate systems.

[0024] Preferably, the specific steps in S4 are as follows:

[0025] S41. Obtain the center point of the road network data of the electronic map, and construct a line feature set, where the line feature set contains road name information;

[0026] S42. Cross-process the line feature set with the target area electronic map surface data set to obtain a second set of points of interest;

[0027] Preferably, a first interest surface is constructed with the second point of interest as the center and a radius, the first set of points of interest is superimposed on the first interest surface, and the second set of points of interest in the first set of points of interest that fall within the first interest surface is removed to obtain a third set of points of interest.

[0028] Preferably, the first map is a remote sensing image map, and S2 further includes the following steps:

[0029] S61. Obtain the pixel value G(c, e, z) of each pixel of the remote sensing image map, where c represents the pixel color value, e represents the center distance between adjacent pixels, and z represents the ground feature.

[0030] S62. Compare and calculate the pixel value G(c, e, n) of the remote sensing image with the model database, where the model database is the standard pixel value g(c0, e0, z0) of common ground objects. The calculation between the pixel value G and the standard pixel value adopts the following formula:

[0031]

[0032] Among them, set a threshold k0, 0 ≤ k0 ≤ 0.001253, and judge whether the Ki value conforms to the K0 interval. If it conforms, then n = z0.

[0033] An electronic device includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein, the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute any one of the methods for extracting a point of interest.

[0034] As can be seen from the above technical solutions, compared with the prior art, the present invention discloses a method for extracting a point of interest, which has the following beneficial effects:

[0035] (1) In the method for extracting a point of interest of the present invention, by converting the rich point-of-interest resources on the Internet, such as Internet point-of-interest resources, to the coordinate system required by the user through coordinate conversion and then integrating them with the municipal survey data, GIS workers can obtain the required point-of-interest resources more conveniently and quickly in batches. At the same time, the Internet online map obtains municipal data, so that to a certain extent, the traditional map resources and the Internet map resources can complement each other's advantages.

[0036] (2) In the method for extracting a point of interest of the present invention, compared with the inaccuracy of the three-parameter method to a certain extent and the calculation redundancy and low efficiency of the seven-parameter method to a certain extent, by selecting the four-parameter model for coordinate conversion, the coordinate conversion between different coordinate systems can be carried out more accurately and conveniently.

[0037] (3) In the method for extracting a point of interest of the present invention, by comparing and calculating the standard pixel value g(c0, e0, z0) of ground objects with the remote sensing image standard database, the required points of interest can be directly obtained from the remote sensing image, expanding the breadth and depth of the point-of-interest data source. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0039] Figure 1 The accompanying drawing is a flowchart of the implementation of the method for extracting points of interest of the present invention;

[0040] Figure 2 The accompanying drawing is a schematic diagram of coordinate conversion of the present invention;

[0041] Figure 3 The accompanying drawing is a schematic diagram of the process for extracting points of interest based on remote sensing images of the present invention;

[0042] Figure 4 The accompanying drawing is a block diagram of an electronic device of the present invention. Detailed implementation manners

[0043] Next, the technical solutions in the embodiments of the present invention will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0044] Embodiment 1

[0045] Obtain a vector surface of a first target area, and the coordinates of the vector surface of the first target area are in a first coordinate system. The acquisition of the vector surface usually uses a vector map as the base map. The user performs vector operations on the places of his own interest to draw the vector surface, and the vector surface has the same coordinate system as the base map.

[0046] Overlay the first map with the vector surface of the first target area to obtain a set of points of interest of the first map. The coordinates of the first map are in the first coordinate system. The set of points of interest of the first map consists of at least one point of interest. The point of interest includes an association table, and the association table contains at least information such as the coordinate information and name of the corresponding point of interest. The source of the first map can be an Internet online map, a remote sensing map, etc. A remote sensing image map usually has its own coordinate system and is expressed with individual pixels as independent elements. Each pixel has an independent value G(ci, ei, n), where c represents the pixel color value, e represents the central distance from the pixel to the adjacent pixels, z represents the ground feature, and these values are stored according to certain rules. In addition, n is a value to be determined.

[0047] The overlay processing process in S2 includes

[0048] S21. Obtain the coordinate information P1 of the first set of points of interest i (X i , Y i ) and the coordinate information P2 of the points on the vector surface of the first target area j (X j , Y j);

[0049] S22. Subtract the coordinates of P1 i from P2 j . When the following formula is satisfied, the process of retaining the difference value of the first set of interest points is calculated using the following formula:

[0050]

[0051] where P1i(Xi, Yi) represents the coordinates of the i-th point in the first set of interest points, Xi represents the X coordinate of the i-th point in the first set of interest points, Yi represents the Y coordinate of the i-th point in the first set of interest points, P2j(Xj, Yj) represents the coordinates of the j-th point in the first target area vector surface, Xj represents the X coordinate value of the j-th point in the first target area vector surface, and Yj represents the Y coordinate of the j-th point in the first target area vector surface in the Y method.

[0052] Intersect the electronic map road network data with the first target area vector surface to obtain the target area electronic map road network data. The coordinates of the electronic map road network data are in the second coordinate system. The electronic map road network data can be the survey data of the municipal planning institute or other data sources. The electronic map road network data includes the target area electronic map road network data and the electronic map surface data of the target area. The road network data includes road width, road name data, and coordinate data. The electronic map surface data includes at least electronic map surface name data and coordinate data;

[0053] Due to the inconsistent coordinates among various map data, if the coordinate system of the first target area vector surface element surface is inconsistent with the second coordinate system of the electronic map road network data, convert the coordinates of the first target area vector surface to the second coordinate system. The common coordinate conversion uses the Bursa conversion model for conversion, that is, on the premise of finding common points, solve various conversion parameters, and then perform coordinate conversion.

[0054] Convert the target area electronic map road network data into a line feature set, and obtain a second set of interest points by intersecting the line feature set with the target area electronic map road network data set; the coordinates of the second set of interest points are in the second coordinate;

[0055] The specific steps in S4 are as follows:

[0056] S41. S41. Obtain the center point of the electronic map road network data and construct a line feature set, and the line feature set includes road name information;

[0057] S42. Cross-process the line feature set with the target area electronic map surface data set to obtain a second set of interest points;

[0058] Further, convert the road network data of the target area electronic map into a line feature set, and obtain a second point of interest set by combining the line feature set with the road network data set of the target area electronic map; the coordinates of the second point of interest set are the second coordinates.

[0059] Further, set a radius with the first point of interest set as the center to construct a first set of interest surfaces, overlay the second point of interest set on the first set of interest surfaces, and remove the first point of interest set where the second point of interest falls within the first set of interest surfaces to obtain a third set of point of interest sets;

[0060] If the first coordinate system of the first point of interest set is inconsistent with the coordinate system of the second point of interest set, convert the first coordinate system of the first point of interest set to the second coordinate system;

[0061] Fuse the first point of interest set and the third point of interest set to obtain the target point of interest.

[0062] Embodiment 2

[0063] Coordinate transformation is the description of the position of spatial entities and is the process of transforming from one coordinate system to another. It is achieved by establishing a one-to-one correspondence between two coordinate systems. It is an essential step in establishing the mathematical basis of maps in the surveying and compilation of maps at various scales. Generally, the coordinates of various map data are inconsistent and need to be transformed. There are many common coordinate transformation methods. This method uses the four-parameter model for calculation and transformation, which is more efficient and of better quality. The specific formula is as follows:

[0064]

[0065] Among them, in the above formula, , represents the coordinates in the Q coordinate system, , represents the coordinates in the G coordinate system, , , , are the coordinate transformation parameters for converting the G coordinate system to the Q coordinate system, , are the translation parameters between the two coordinates, represents the scaling parameter between the two coordinate systems, represents the rotation parameter between the two coordinate systems. Among them, it is necessary for operators or computers to judge the different coordinate values of the same-name points in the two coordinate systems and then calculate the coordinate values through the above formula.

[0066] Embodiment 3

[0067] There are a large number of satellite remote sensing images in existing electronic maps. Such images have characteristics such as fast update rate, wide acquisition range, and relatively low cost. However, remote sensing images do not have existing points of interest and need to be processed and extracted based on the characteristics of remote sensing image data. The present invention proposes a method for extracting points of interest from remote sensing images, and the specific steps are as follows:

[0068] Obtain the pixel value G(ci, ei, n) of each pixel in the remote sensing image map, where c represents the pixel color value, e represents the central distance between adjacent pixels, and n represents the ground feature; the resolutions of different remote sensing images are different, and there are respective standards for color values and pixel sizes. Common remote sensing images include: worldview series, spot series, and high-resolution series in our country, etc. Therefore, when making the standard pixel value g(c0, e0, z0) of common ground features, it is necessary to classify and make the corresponding standard pixel value g(c0, e0, z0) of common ground features according to the type of image.

[0069] Compare and calculate the pixel value G(ci, ei, n) with the model database, and the model database is the standard pixel value g(c0, e0, z0) of common ground features. Among them, the calculation of the pixel value G and the standard pixel value adopts the following formula:

[0070] , where a threshold k0 is set, 0 ≤ k0 ≤ 0.001253. If Ki meets the K0 interval, then n = z0. This method has a simple structure and can quickly extract the task of points of interest according to the computing power of the computer.

[0071] Example 4

[0072] The present application provides a non-volatile computer-readable storage medium, on which computer program instructions are stored. When the computer program instructions are executed by a processor, the method for extracting a point of interest is implemented. As Figure 4 described. The non-volatile computer-readable storage medium represents various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smart phones, wearable devices, and other similar computing devices. The components shown in this article, their connections and relationships, and their functions are only examples and are not intended to limit the implementation of the present application described and / or required in this article.

[0073] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts among the various embodiments can be referred to each other.

[0074] The foregoing description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Thus, the present invention is not limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0075] Those skilled in the art will appreciate that embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

[0076] The present invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each flow and / or block of the flowchart illustrations and / or block diagrams, and combinations of flows and / or blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to the processors of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing device to produce a machine, such that the instructions executed by the processors of the computer or other programmable data processing device create means for implementing the functions specified in Figure 1 one or more of the flows Figure 1 or blocks or combinations of blocks.

[0077] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means that implement the functions specified in Figure 1 one or more of the flows Figure 1 or blocks or combinations of blocks.

[0078] These computer program instructions may also be loaded onto a computer or other programmable data processing device, such that a series of operational steps are performed on the computer or other programmable device to produce a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in Figure 1 one or more of the flows Figure 1 or blocks or combinations of blocks.

[0079] In a typical configuration, a computing device includes one or more processors (CPUs), an input / output interface, a network interface, and memory. The memory may include non-permanent memory in the form of computer-readable media, random access memory (RAM), and / or non-volatile memory such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0080] Computer-readable media includes both permanent and non-permanent, removable and non-removable media implemented by any method or technology for information storage. The information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic tape disk storage or other magnetic storage devices, or any other non-transitory medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transitory media such as modulated data signals and carrier waves.

[0081] It should also be noted that: First, in the drawings of the disclosed embodiments of the present invention, only the structures related to the disclosed embodiments are involved, and other structures can refer to the general design. Without conflict, the same and different embodiments of the present invention can be combined with each other;

[0082] Second: This application can be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform specific tasks or implement specific abstract data types. This application can also be practiced in a distributed computing environment where tasks are performed by remote processing devices connected through a communication network. In a distributed computing environment, program modules can be located in local and remote computer storage media including storage devices.

[0083] Finally: The above are only the preferred embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for extracting points of interest, characterized in that, Including the following steps: S1. Obtain the vector surface of the first target area, and the coordinates of the vector surface of the first target area are in the first coordinate system; S2. Superimpose the first map and the vector surface of the first target area to obtain the first map point of interest set. The coordinates of the first map are in the first coordinate system. The first map point of interest set consists of at least one point of interest. The point of interest includes an association table, and the association table includes the corresponding point of interest coordinate system and the point of interest name; S3. Intersect the electronic map road network data with the vector surface of the first target area to obtain the electronic map road network data of the target area. The coordinates of the map road network data are in the second coordinate system; The electronic map road network data includes electronic map road network data and electronic map surface data. The road network data includes road width, road name data and coordinate data. The electronic map surface data includes electronic map surface name data and coordinate data; Wherein, if the coordinate system of the element surface of the vector surface of the first target area is inconsistent with the second coordinate system of the electronic map road network data, convert the coordinates of the vector surface of the first target area to the second coordinate system; S4. Convert the electronic map road network data of the target area into a line feature set, and intersect the line feature set with the electronic map surface data set of the target area to obtain a second point of interest set; the coordinates of the second point of interest set are in the second coordinate; S5. Set a radius with the first point of interest set as the center to construct a first interest surface set, superimpose the second point of interest set on the first interest surface set, and remove the first point of interest set where the second point of interest falls in the first interest surface set to obtain a third point of interest set; If the first coordinate system of the first point of interest set is inconsistent with the coordinate system of the second point of interest set, convert the first coordinate system of the first point of interest set to the second coordinate system; S6. Integrate the first point of interest set and the third point of interest set to obtain the target point of interest; The superimposing process in S2 is as follows: S21. Obtain the coordinate information P1 of the first set of interest points i (X i , Y i ) and the coordinate information P2 of the vector surface points of the first target area j (X j , Y j ); S22. Subtract the coordinates of P1 i from those of P2 j . When the following formula is satisfied, the process of retaining the difference value of the first set of interest points adopts the following formula Formula calculation: Among them, P1 i (X i , Y i ) represents the coordinates of the i-th point in the first set of points of interest, where X i represents the X-method coordinate of the i-th point in the first set of points of interest, and Y i represents the Y-method coordinate of the i-th point in the first set of points of interest. P2 j (X j , Y j ) represents the coordinates of the j-th point in the first target area vector surface, where X j represents the X-method coordinate value of the j-th point in the first target area vector surface, and Y j represents the coordinate of the j-th point in the first target area vector surface in the Y-method; The coordinate conversion method adopts a four-parameter model.

2. The extraction method of a point of interest according to claim 1, characterized in that The coordinate conversion method adopts a four-parameter model, and the specific model is as follows: Among them, in the above formula, X Q , Y Q represent the coordinates in the Q coordinate system, X G , Y G represent the coordinates in the G coordinate system, are the coordinate transformation parameters for converting the G coordinate system to the Q coordinate system, x0 and y0 are the translation parameters between the two coordinates, α represents the scaling parameter between the two coordinate systems, and β represents the rotation parameter between the two coordinate systems.

3. The method for extracting a point of interest according to claim 1, wherein The specific steps in S4 are as follows: S41. Obtain the center point of the electronic map road network data and construct a line feature set, and the line feature set includes road name information; S42. Cross-process the line feature set with the electronic map surface data set of the target area to obtain a second point of interest set.

4. A method for extracting points of interest according to any one of claims 1 to 3, characterized in that Set a radius with the second point of interest as the center to construct a first interest surface, superimpose the first point of interest set on the first interest surface, and remove the second point of interest set where the first point of interest set falls in the first interest surface to obtain a third point of interest set.

5. The extraction method of a point of interest according to claim 4, characterized in that The first map is a remote sensing image map, and S2 further includes the following steps: S61. Obtain the pixel value G(ci,ei,n) of each pixel of the remote sensing image map, where c represents the pixel color value, e represents the central distance between adjacent pixels, and n represents the ground feature; S62. Compare and calculate the pixel value G(ci, ei, n) with the model database, where the model database is the standard pixel value g(c0, e0, z0) of common ground objects; among them, the calculation of the pixel value G and the standard pixel value adopts the following formula: Ki = (ci - c0) 2 + (ei - e0) 2 Where, a threshold k0 is set, 0 ≤ k0 ≤ 0.001253. If Ki meets the K0 interval, then n = z0.

6. An electronic device, characterized in that, Including: At least one processor; And a memory communicatively connected to the at least one processor; wherein, the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the method according to any one of claims 1-5.

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