Information processing device

Abstract

To reduce the cost of providing point cloud data.SOLUTION: An information processing device that stores and provides point cloud data, includes: a storage unit that stores a plurality of footprints, each corresponding to a predetermined geographical area in association with point cloud data being information obtained for multiple locations included in each footprint; and a control unit that executes the steps of accepting designation of a first area, specifying one or more footprints that encompass the first area, and extracting the point cloud data corresponding to the specified footprints.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] This disclosure relates to data collection. [Background technology]

[0002] There is a technology that uses point cloud data obtained by laser surveying etc. to generate highly accurate map data. In this regard, for example, Patent Document 1 discloses an invention related to a system that removes measurement data from point cloud data and transfers the data between devices in order to compress the amount of point cloud data. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-043475 [Patent Document 2] Patent Publication No. 2021-098419 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure aims to reduce the cost of providing point cloud data. [Means for solving the problem]

[0005] One aspect of the present disclosure is to The information processing device stores and provides point cloud data, and has a memory unit that stores a plurality of footprints, each of which corresponds to a specified geographical area, in association with point cloud data, which is information obtained about a plurality of points included in each footprint, and a control unit that accepts designation of a first area, identifies one or more footprints that encompass the first area, and extracts the point cloud data that corresponds to the identified footprint.

[0006] Further, other aspects include a method executed by the above-mentioned information processing device, a program for causing a computer to execute the method, or a computer-readable storage medium non-transiently storing the program. Effect of the Invention

[0007] According to the present disclosure, the cost of providing point cloud data can be reduced. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram for explaining an overview of a system according to an embodiment. [Diagram 2] FIG. 2 is a diagram illustrating the configuration of a user device and a server device. [Diagram 3] FIG. 2 is a diagram for explaining the relationship between a footprint and point cloud data. [Figure 4] FIG. 2 is a diagram for explaining a point cloud database and reference data. [Diagram 5] 5A to 5C are diagrams for explaining a process of identifying a footprint. [Figure 6] FIG. 4 is a sequence diagram of processes executed by a user device and a server device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] There is a technology to obtain point cloud data by aerial surveying and use it for generating maps, etc. In aerial surveying, for example, a device such as LiDAR is mounted on an aircraft, laser light is emitted to the ground surface, and the unevenness of the ground surface can be measured by measuring the arrival time of the reflected wave.

[0010] The range that a laser beam emitted from an aircraft reaches on the ground is called a footprint. In aerial surveying, laser light is emitted multiple times at different positions (measurement points) within the footprint. In other words, one footprint includes multiple measurement points. The coordinates and height of each measurement point can be obtained by performing calculations on the raw data obtained from the multiple measurement points using the aircraft's position information, altitude information, and attitude information. Information obtained at one or more measurement points is also called point cloud data. Point cloud data is composed of, for example, three-dimensional coordinate information of the measurement points. By using point cloud data obtained through aerial surveying, it is possible to generate highly accurate three-dimensional maps.

[0011] However, when measuring the shape of an object by irradiating it with laser light, a characteristic of the method is that the amount of data generated is large. For example, laser light is irradiated from an aircraft to the ground surface tens of thousands of times per second. The area to be measured can be several kilometers in size. As the number of measurement points and the number of irradiations increase, the amount of point cloud data also increases, so that depending on the measurement results, the amount of point cloud data obtained from a single measurement can reach tens to hundreds of gigabytes. Therefore, when transferring point cloud data obtained in this manner between devices, the key point is how to reduce the amount of calculations and data.

[0012] For example, consider the case where a consumer of point cloud data accesses a server device that provides point cloud data and requests the provision of point cloud data corresponding to a certain area. The server device must extract the point cloud data included in the specified area from the storage device. However, if the amount of data is huge, searching for and inputting and outputting the data may be very costly. The information processing device according to this embodiment solves such a problem.

[0013] An information processing device according to one embodiment is an information processing device that stores and provides point cloud data, and has a memory unit that stores a plurality of footprints, each of which corresponds to a specified geographical area, in association with point cloud data, which is information obtained about a plurality of points included in each footprint, and a control unit that receives designation of a first area, identifies one or more footprints that encompass the first area, and extracts the point cloud data that corresponds to the identified footprint.

[0014] The storage unit stores the footprints in association with the point cloud data included in the footprints. A footprint is an area irradiated with a laser beam during measurement, and each footprint has a predetermined geographical area. The storage unit may store data for identifying a geographical area of ​​the footprint in association with the point cloud data.

[0015] Furthermore, the storage unit may have a plurality of storage areas allocated to each footprint, and the point cloud data acquired within the corresponding footprint may be stored in each of the plurality of storage areas. The plurality of storage areas may be logically divided or may be physically divided.

[0016] The storage unit may store position information of a plurality of footprints in association with a reference to a storage area in which point cloud data acquired in each footprint is stored. The reference to the storage area may be an identifier for identifying a storage location of data in the device (e.g., a table space in a database, a directory in a file system, a URI, etc.).

[0017] The control unit is configured to generate one or more footprints that include a first area designated by a consumer. A first area may be specified. Also, a storage area in which point cloud data corresponding to the specified footprint is stored may be specified. The first area is an area for which point cloud data is requested by a consumer (also referred to as an area of ​​interest). This makes it possible to specify a storage area in which point cloud data included in the requested area of ​​interest is stored, and to quickly extract the required point cloud data.

[0018] The control unit may receive a designation of the first area from an external device (eg, a device used by a consumer) and transmit an identifier of the identified storage area to the external device.

[0019] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The configurations of the following embodiments are merely examples, and the present disclosure is not limited to the configurations of the embodiments.

[0020] First Embodiment An overview of a data providing system according to a first embodiment will be described. The data providing system according to this embodiment includes a server device 2 that stores point cloud data obtained by aerial surveying, and a user device 1 that receives the point cloud data from the server device 2.

[0021] An overview of the processing performed by the system will be described with reference to FIG. The server device 2 stores point cloud data obtained by aerial surveying. The point cloud data is acquired in footprint units. A footprint is an area irradiated with a beam of laser light used in aerial surveying. The point cloud data includes values ​​(e.g., three-dimensional coordinates) calculated based on measurement results at measurement points. One footprint includes, for example, tens of thousands of point cloud data. The server device 2 stores the acquired point cloud data in different storage areas (e.g., files, directories, table spaces, etc.) for each footprint.

[0022] The user device 1 is a device associated with a consumer who uses point cloud data. The user device 1 may be, for example, a device used by a business that provides a predetermined service (for example, a service for generating three-dimensional map data) using point cloud data. The user device 1 requests the server device 2 to provide the point cloud data, and acquires the corresponding point cloud data from the server device 2.

[0023] The user device 1 specifies an area for which the user desires to receive point cloud data (hereinafter, referred to as an area of ​​interest) to the server device 2. The server device 2 identifies one or more footprints that include the area of ​​interest, and then identifies a storage area in which point cloud data corresponding to the footprint is stored. If the area of ​​interest spans multiple footprints, multiple storage areas may be identified. The identified footprint includes the area of ​​interest. In other words, all of the point cloud data acquired within the area of ​​interest is stored in the identified multiple storage areas. In other words, by extracting all of the point cloud data included in the identified storage areas, all of the point cloud data acquired within the area of ​​interest can be obtained.

[0024] The server device 2 extracts the point cloud data from the identified storage area, and provides the extracted point cloud data to the user device 1. In this embodiment, the server device 2 may notify the user device 1 of an identifier (e.g., a URI or the like) for externally accessing the identified one or more storage areas, and cause the user device 1 to download the point cloud data from the storage area.

[0025] [Device configuration] FIG. 2 is a diagram showing an example of the configuration of the user device 1 and the server device 2. As shown in FIG.

[0026] The user device 1 may be, for example, a personal computer, a smartphone, a mobile phone, a tablet, The user device 1 is a computer used by an individual, such as a laptop computer, a personal computer terminal, etc. The user device 1 includes a control unit 11, a storage unit 12, a communication unit 13, and an input / output unit .

[0027] The control unit 11 is a calculation device that controls the user device 1. The control unit 11 can be realized by a calculation processing device such as a CPU (Central Processing Unit). The unit 11 executes a function of accessing the server device 2 and performing an interaction. This function may be realized by a web browser running on the user device 1 or dedicated application software.

[0028] The storage unit 12 includes a main storage device and an auxiliary storage device. The main storage device is a memory in which the programs executed by the control unit 11 and data used by the control programs are expanded. The auxiliary storage device is a device in which the programs executed by the control unit 11 and data used by the control programs are stored. The auxiliary storage device may store the programs executed by the control unit 11 packaged as applications. It may also store an operating system for executing these applications. The programs stored in the auxiliary storage device are loaded into the main storage device and executed by the control unit 11, thereby performing the processes described below.

[0029] The primary storage device may include a random access memory (RAM) or a read only memory (ROM). The secondary storage device may include an erasable programmable read only memory (EPROM) or a hard disk drive (HDD). It may also include a disk drive (HDD, Hard Disk Drive). may include removable media, i.e., portable recording media.

[0030] The communication unit 13 is a wireless communication interface for connecting the user device 1 to a network. The communication unit 13 is configured to be able to communicate with the server device 2 via, for example, a wireless LAN or a mobile communication service such as 3G, 4G, or 5G. The input / output unit 14 is a unit that accepts input operations performed by the user and presents information to the user. In this embodiment, it is made up of a single touch panel display. That is, it is made up of a liquid crystal display and its control means, and a touch panel and its control means.

[0031] Next, the server device 2 will be described. The server device 2 is, for example, a computer such as a server device, a personal computer, a smartphone, a mobile phone, a tablet computer, a personal information terminal, etc. The server device 2 includes a control unit 21, a storage unit 22, and a communication unit 23.

[0032] The server device 2 is configured to have a database (point cloud database) that stores point cloud data acquired by aerial surveying using an aircraft. The server device 2 also provides the point cloud data stored in the point cloud database in response to a request from the user device 1.

[0033] The server device 2 can be configured as a computer having a processor (CPU, GPU, etc.), a main storage device (RAM, ROM, etc.), and an auxiliary storage device (EPROM, hard disk drive, removable media, etc.). The auxiliary storage device stores an operating system (OS), various programs, various tables, etc., and by executing the programs stored therein, various functions (software modules) that match a predetermined purpose, as described below, can be realized. However, some or all of the functions may be realized as hardware modules by hardware circuits such as ASICs and FPGAs.

[0034] The control unit 21 executes a predetermined program to realize various functions of the server device 2. The control unit 21 is a calculation unit that performs processing such as the processing of the data and the like. The control unit 21 can be realized by a hardware processor such as a CPU. The control unit 21 may also be configured to include a RAM, a ROM (Read Only Memory), a cache memory, and the like.

[0035] The control unit 21 is configured to have two software modules: a data acquisition unit 211 and a data provision unit 212. Each software module may be realized by causing the control unit 21 (CPU) to execute a program stored in the storage unit 22, which will be described later.

[0036] The data acquisition unit 211 acquires point cloud data obtained by aerial surveying via a specified interface. Point cloud data is a set of coordinates (X coordinate, Y coordinate, Z coordinate) in a three-dimensional space. The coordinates may be, for example, a combination of latitude, longitude, and altitude expressed in a specified geodetic system. In aerial surveying, a laser pulse is irradiated from an aircraft to the ground surface, and the three-dimensional coordinates corresponding to a certain measurement point can be obtained based on the information obtained by the reflected pulse and the results of measuring the position and attitude of the aircraft. Note that the coordinates corresponding to the point cloud data may be corrected for the effects of buildings, trees, etc.

[0037] The point cloud data is associated with a footprint. A footprint is an area (laser spot) irradiated with a light beam of a laser pulse used in aerial surveying. In this embodiment, information for identifying the geographical area of ​​the footprint and point cloud data acquired within the footprint are input to the server device 2 in an associated state. The geographical area of ​​the footprint may be represented, for example, by a set of coordinates on the boundary line of the footprint or a set of coordinates contained in the footprint. The geographical area of ​​the footprint may be represented, for example, by GIS (Geographic Information System) data such as a Shapefile.

[0038] FIG. 3 is a diagram showing the relationship between footprints and point cloud data. In this example, nine footprints, A to H, are illustrated. References A1 to A10 represent measurement points included in footprint A. References B1 to B9 represent measurement points included in footprint B. Point cloud data is acquired at each measurement point. Note that in this example, footprint A includes 10 measurement points and footprint B includes 9 measurement points, but one footprint may include several thousand to tens of thousands of measurement points.

[0039] The point cloud data acquired by the data acquisition unit 211 is stored in a point cloud database provided in the storage unit 22, which will be described later. In this embodiment, the point cloud database holds point cloud data for each footprint. Furthermore, the data acquisition unit 211 generates reference data for identifying a storage area in which the point cloud data is to be stored, and stores the reference data in the storage unit 22. A specific method will be described later.

[0040] The data providing unit 212 receives a request for acquiring point cloud data from the user device 1, and transmits the requested point cloud data to the user device 1 in response to the request. Specifically, the data providing unit 212 acquires a designation of an area (area of ​​interest) for which point cloud data is desired to be provided from the user device 1. The data providing unit 212 identifies one or more footprints that include the entire area of ​​interest, and then identifies one or more storage areas in which point cloud data corresponding to the footprints is stored. The data providing unit 212 also provides the point cloud data stored in the identified storage areas to the user device 1. The data providing unit 212 may be capable of executing a web server or the like for accepting access from the user device 1.

[0041] The storage unit 22 is a means for storing information, and is configured with a storage medium such as a RAM, a magnetic disk, or a flash memory. The program, data used by the program, etc. are stored.

[0042] The storage unit 22 stores a point cloud database, which is a database in which point cloud data is stored, and reference data.

[0043] FIG. 4A is a diagram illustrating the configuration of a point cloud database. As shown in the figure, the point cloud database is composed of multiple storage areas. The multiple storage areas may be logically divided storage areas or physically divided storage areas. For example, the storage areas may be tables or table spaces in a database, or files or directories in a file system.

[0044] In this embodiment, a storage area is prepared for each footprint, and a certain storage area stores point cloud data acquired for the corresponding footprint. In the illustrated example, storage area X1 corresponding to footprint A stores 10 point cloud data items A1 to A10. Storage area X2 corresponding to footprint B stores 9 point cloud data items B1 to B9. The data acquisition unit 211 stores the acquired point cloud data in a storage area associated with the corresponding footprint.

[0045] FIG. 4B is an example of the reference data. The reference data is data that stores the relationship between a footprint and a storage area associated with the footprint, and is generated and updated by the data acquisition unit 211.

[0046] In this example, the reference data includes a footprint ID, geographic information, and reference information. The footprint ID is an identifier that uniquely identifies a footprint. Geographic information is information that identifies the geographic area contained in the footprint, such as a set of coordinates that the footprint contains, a set of coordinates on the footprint's boundary, etc. By referencing this information, it is possible to identify which footprint contains an arbitrary point. The reference information is a reference to a storage area associated with the footprint, such as a storage device name, a database name, a table space name, a directory name, a file name, a file descriptor, a URI, or a combination of these. When the data acquisition unit 211 acquires new point cloud data corresponding to a certain footprint, it adds a record of the reference data.

[0047] Returning to Figure 2, we will continue with the explanation. The communication unit 23 is a wireless communication interface for connecting the server device 2 to a network. The communication unit 23 is configured to be able to communicate with the user device 1 via, for example, a wireless LAN or a mobile communication service such as 3G, 4G, or 5G.

[0048] The specific hardware configurations of the user device 1 and the server device 2 may include omissions, substitutions, and additions of components as appropriate depending on the embodiment. For example, the control units 11 and 21 may include multiple hardware processors. The hardware processor may be configured with a microprocessor, FPGA, GPU, etc. Also, input / output devices other than those illustrated (for example, an optical drive, etc.) may be added. Also, the server device 2 may be configured with multiple computers. In this case, the hardware configurations of the computers may or may not be the same.

[0049] [How to extract point cloud data] Next, a process in which the server device 2 extracts point cloud data based on a request from the user device 1 will be described in detail. The user device 1 transmits a request including an area (area of ​​interest) for which point cloud data is desired to be provided to the server device 2. Here, it is assumed that the point cloud data has been acquired by a footprint as shown in Fig. 3. Fig. 5 is a diagram in which the area of ​​interest specified by the user device 1 is superimposed on Fig. 3.

[0050] Here, in order to obtain all the point cloud data contained in the area of ​​interest, it is necessary to identify one or more footprints that encompass the area of ​​interest (i.e., that include the entire area of ​​interest). In this example, the data providing unit 212 identifies nine footprints, A to H, as footprints that encompass the area of ​​interest. The one or more footprints that encompass the area of ​​interest can be identified based on information that represents the geographical region of the area of ​​interest and geographic information of multiple footprints recorded in the reference data.

[0051] The data providing unit 212 provides all point cloud data included in the identified footprint to the user device 1. The point cloud data included in the identified footprint can be extracted by referring to the reference data. For example, when nine footprints A to H are identified, the data providing unit 212 refers to the reference data and acquires reference information corresponding to each of the nine footprints. This makes it possible to identify a storage area for acquiring the point cloud data included in the nine footprints.

[0052] The data providing unit 212 acquires all the point cloud data stored in the nine identified storage areas, and transmits the data to the user device 1.

[0053] In this embodiment, the data providing unit 212 executes a file server and is configured to be able to provide point cloud data to an external device via the file server. The data providing unit 212 generates information for accessing the point cloud data from an external device based on the acquired reference information and provides the information to the user device 1. Examples of such information include a network address, a file path, or a URI of the server device 2.

[0054] [Processing flow] Next, a description will be given of the flow of the processes executed by the user device 1 and the server device 2. FIG 6 is a sequence diagram of the processes executed by the user device 1 and the server device 2.

[0055] First, in step S11, the user device 1 accepts a designation of an area of ​​interest. The area of ​​interest may be acquired from an operator of the user device 1 via the input / output unit 14. The operator of the user device 1 may designate the area of ​​interest, for example, by drawing an area on a map. The user device 1 transmits a request including the specified area of ​​interest to the server device 2 .

[0056] In step S12, the server device 2 identifies one or more footprints that include the specified area of ​​interest. The server device 2 also identifies a storage area in which point cloud data corresponding to the identified footprints is stored. A footprint encompassing the area of ​​interest can be determined by matching the geographic area of ​​the area of ​​interest with geographic information contained in the reference data. In this step, the server device 2 provides information for accessing the identified storage area to the user device 1. The server device 2 provides a storage device name, a database name, a table space name, a directory name, a file name, a file descriptor, a URI, or a combination of these. The match may be provided to the user device 1.

[0057] In step S13, the user device 1 accesses the file server operating in the server device 2, and downloads all of the point cloud data stored in the storage area indicated by the server device 2.

[0058] As described above, the server device 2 according to the first embodiment stores point cloud data acquired by aerial surveying in a different storage area for each footprint. In addition, after identifying multiple footprints that include an area of ​​interest, the server device 2 provides the user device 1 with the point cloud data stored in the corresponding storage area.

[0059] According to this configuration, it becomes possible to quickly acquire all point cloud data acquired within a specified area of ​​interest. As a method for extracting point cloud data acquired within a specified area of ​​interest, for example, there is a method for determining whether or not measurement points corresponding to a plurality of stored point cloud data are within the boundary line surrounding the area of ​​interest using latitude and longitude. However, when using this method, as the number of point cloud data stored in the point cloud database increases, the amount of calculation required also increases, which may cause processing delays. On the other hand, according to the method of the present embodiment, it is possible to extract point cloud data with a small amount of calculation.

[0060] (Modification) The above-described embodiment is merely an example, and the present disclosure can be modified and implemented as appropriate without departing from the spirit and scope of the present disclosure. For example, the processes and means described in this disclosure can be freely combined and implemented as long as no technical contradiction occurs.

[0061] In the description of the embodiment, the device that stores the point cloud data and the device that provides the reference to the user device 1 are the same device, but they may be separate devices. For example, a storage server that stores the point cloud data may be provided in addition to the server device 2, and the server device 2 may store the point cloud data in the storage server instead of the storage unit 22. In this case, only the reference data may be stored in the storage unit 22. In this case, the reference information may be composed of an identifier or network address of the storage server, an identifier of the storage container, or the like. In this case, the user device 1 may access the storage server based on such information and download the point cloud data.

[0062] In the embodiment, the server device 2 provides the user device 1 with a reference to the point cloud data, and the user device 1 downloads the point cloud data via a file server, but the reference does not necessarily need to be transmitted and received between the devices. For example, when step S12 is completed, the server device 2 may extract the target point cloud data, archive the extracted multiple point cloud data, and transmit them to the user device 1.

[0063] In addition, in the description of the embodiment, the footprint is defined as the area where the laser light beam emitted from an aircraft reaches the ground, but the footprint may be any other area as long as it is a unit area for performing laser surveying.

[0064] Furthermore, a process described as being performed by one device may be shared and executed by multiple devices. Alternatively, a process described as being performed by different devices may be executed by one device. In a computer system, the hardware configuration (server configuration) by which each function is realized can be flexibly changed.

[0065] The present disclosure can also be realized by supplying a computer program implementing the functions described in the above embodiments to a computer, and having one or more processors of the computer read and execute the program. Such a computer program may be provided to the computer by a non-transitory computer-readable storage medium connectable to the system bus of the computer, or may be provided to the computer via a network. Non-transitory computer-readable storage media include, for example, any type of disk, such as a magnetic disk (floppy disk, hard disk drive (HDD), etc.), an optical disk (CD-ROM, DVD disk, Blu-ray disk, etc.), a read-only memory (ROM), a random access memory (RAM), an EPROM, an EEPROM, a magnetic card, a flash memory, an optical card, and any type of medium suitable for storing electronic instructions. [Explanation of symbols]

[0066] 1. User device 2. Server device 11,21 Control section 12,22...Storage section 13,23 Communications Department 14...Input / output section

Claims

1. An information processing device for storing and providing point cloud data, a storage unit that stores a plurality of footprints, each of which corresponds to a predetermined geographical area, and point cloud data, which is information obtained for a plurality of points included in each footprint, in association with each other; accepting a designation of a first area and identifying one or more footprints that encompass the first area; Extracting the point cloud data corresponding to the identified footprint; A control unit that executes the above. An information processing device having the above configuration.

2. the storage unit has a plurality of storage areas allocated to each footprint, and point cloud data acquired within a corresponding footprint is stored in each of the plurality of storage areas; The information processing device according to claim 1 .

3. the storage unit stores position information of a plurality of footprints in association with a reference to a storage area in which point cloud data acquired within each footprint is stored; The information processing device according to claim 2 .

4. the control unit identifies one or more of the storage areas corresponding to the identified one or more footprints; Extracting point cloud data stored in the specified storage area; The information processing device according to claim 3 .

5. the control unit accepts designation of the first area from an external device, and transmits an identifier of the specified storage area to the external device; The information processing device according to claim 4.

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