CN113568995B

CN113568995B - Dynamic tile map manufacturing method and tile map system based on search conditions

Info

Publication number: CN113568995B
Application number: CN202110699435.XA
Authority: CN
Inventors: 宋礼仪
Original assignee: Shujian Technology Suzhou Co ltd
Current assignee: Shujian Technology Suzhou Co ltd
Priority date: 2021-05-11
Filing date: 2021-06-23
Publication date: 2023-08-01
Anticipated expiration: 2041-06-23
Also published as: CN113568995A

Abstract

The invention discloses a dynamic tile map manufacturing method and a tile map system based on search conditions, wherein the method comprises the following steps: s1, performing service access on a pre-created image map information database, and transmitting map browsing parameters as search conditions; s2, searching from a database according to the input search condition to obtain a target image data list; s3, analyzing the target image data list, and coding the analysis result of the target image data list and the personalized browsing parameters; s4, acquiring corresponding tiles from the specific storage area according to the coding result, if the acquisition is successful, directly returning the acquired tiles to the client, otherwise, executing S5-S6; s5, generating corresponding tiles according to the target image data list and the analysis result; s6, writing the generated tile and the coding result of the corresponding analysis result into a specific storage area, and returning. And a full-filling and return tile generation mechanism and a retrieval response mechanism for constructing a cache key value are adopted, so that the system performance is ensured.

Description

Dynamic tile map manufacturing method and tile map system based on search conditions

Technical Field

The invention relates to the field of maps, in particular to a dynamic tile map manufacturing method and a tile map system based on search conditions.

Background

Conventional raster tile map service (Web Map Tile Service, WMTS) is manufactured by first performing raster data slicing, organizing the data in an orderly fashion, and then performing tile map slicing and map distribution. The traditional processing mode can not meet the personalized browsing requirement of a user, and the slicing of raster data and the storage of sliced data consume a large amount of time and occupy a large amount of storage, so that the requirements of continuous increase of user data and personalized search condition setting can not be met.

The "user-customized browsing requirement" refers to that in the daily browsing of the grid tile map service, as the grid data of the user continuously increases, the user wants to dynamically browse the tile map service of a certain area according to the user-defined search conditions (such as product type, satellite, sensor, shooting time, etc.) and arrangement mode, etc.

The user's raster data may be accumulated over time, and the raster data may include expansion information such as a production department, a product level, a product type, a photographing time, a photographing satellite sensor type, and the like, in addition to basic location information. According to the traditional tile map manufacturing mode, N tile map services are required to be manufactured to meet the personalized browsing requirements of users, so that management trouble can be brought to the users, a large amount of time and storage space can be wasted, and after data are updated, the corresponding services need to be sliced again, so that the daily requirements of the users can not be met.

At present, a manufacturing method of a high-efficiency grid dynamic tile map meeting the search conditions and personalized browsing requirements on the premise of guaranteeing browsing efficiency is lacking.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a dynamic tile map manufacturing method and a tile map system based on search conditions, and a user can browse grid tile map services of a corresponding area through the service directly according to the search conditions set by the user without performing operations such as data slicing after data updating.

The general concept of the invention is as follows: the method comprises the steps of inputting raster data space information, paths and expansion information into a database, creating indexes in space fields and attribute fields, and generating unique number identifiers for each raster picture; when a user browses a certain area based on the search conditions, calculating the area range corresponding to the tile, and acquiring a grid file list meeting the conditions from a database in combination with other search conditions and a sequencing mode; and (3) calculating MD5 codes (or other unique codes) according to the returned data number list and personalized tile browsing parameters (tile formats png, jpg, transparency, brightness and the like), acquiring cached pictures from a cache (a data database, a memory hash table and the like) according to the MD5 codes, returning if the acquisition is successful, generating new grid tiles according to the image list and the tile request information if the acquisition is unsuccessful, writing into the cache and returning. The specific technical scheme is as follows:

the invention provides a WMTS dynamic tile map manufacturing method based on search conditions, which is executed by a tile map system, wherein the tile map system comprises a database and a tile generation module, and the WMTS dynamic tile map manufacturing method comprises the following steps:

s1, performing service access on a pre-created image map information database, and introducing map browsing parameters as search conditions, wherein the search conditions comprise a hierarchy of tile requests, a line number, a range corresponding to column number calculation and attribute conditions aiming at image file expansion, and the attribute conditions aiming at image file expansion are one or more of image auxiliary information defined when the image map information database is pre-created;

s2, searching to obtain a target image data list from the image map information database according to the input search condition;

s3, analyzing the target image data list, and carrying out tile data coding by combining the target image data list and the personalized browsing parameters to obtain a coding result;

s4, acquiring corresponding tiles from the specific storage area according to the coding result, if the acquisition is successful, directly returning the acquired tiles to the client, otherwise, executing S5-S6; wherein the specific storage area is different from the storage address of the image map information database;

s5, calling a tile generation module according to the target image data list and the analysis result thereof to generate a corresponding tile;

and S6, writing the generated tiles and the coding results of the corresponding analysis results into the specific storage area, and returning the generated tiles to the client.

Further, the step of calling the tile generation module to generate the corresponding tile includes:

s501, acquiring the number of image files of the target image data list, traversing the list to acquire image files i, initializing the i to 0, executing S502 if the i is smaller than the number of the files, otherwise executing S507;

s502, if the coordinate system of the image file i is inconsistent with the tile coordinate system, executing S503-S505,

otherwise, executing S506;

s503, converting an image external rectangle corresponding to a tile to be generated into a coordinate range corresponding to the image file i, and performing cutting operation on an area of the image file i in the converted image external rectangle range to obtain a first cutting file;

s504, the first clipping file is put into a memory and is subjected to memory file reprojection transformation,

enabling the memory file coordinate system to be consistent with the tile coordinate system;

s505, clipping the memory file after the re-projection transformation according to the external rectangular range of the image corresponding to the tile to be generated to obtain a second clipping file, filling the second clipping file into the corresponding buffer area of the tile to be generated, and executing S507;

s506, clipping the image file i according to the external rectangular range of the image corresponding to the tile to be generated to obtain a third clipping file, filling the third clipping file into a corresponding buffer area of the tile to be generated, and executing S507;

s507, if all areas of the tile to be generated are filled, executing S508, otherwise, executing self-addition and update numerical value operation on i, and returning to executing S501;

s508, the filled file is processed according to the personalized browsing parameters of the tiles and compressed into tile images.

Further, S1 is preceded by pre-creating an image map information database by:

s001, defining an auxiliary information category of the image raster data stored in the database, and creating an index between the auxiliary information and the image raster data, wherein the auxiliary information category comprises one or more of a file path, affine transformation information, space information, coordinate system information, satellite type, sensor type, product type, shooting time, production department information and arrangement mode;

s002, reading the file list in the appointed directory, and recording the image files in the file list and the corresponding auxiliary information thereof into the database one by one.

Further, in step S002, before entering the image file into the database, the method further includes:

and judging whether the image file is the image data of EPSG 4326, if so, recording the image file into a database, otherwise, converting the corresponding image external rectangle into the EPSG 4326 format, and recording the image file with the converted format into the database.

Further, in step S3, the personalized browsing parameters include one or more of tile format, transparent color, brightness, and RGB color values, the target image data list and the personalized browsing parameters are formatted into character strings, and the formatted character strings are encoded.

Further, the formatted character string is encoded by means of encryption or non-encryption.

Further, step S2 further includes:

the input search conditions comprise space information of a hierarchy, a line number and a column number corresponding to the tile and other parameters, and a target image data list meeting other parameter conditions is searched from the image map information database according to the space information.

Optionally, the specific storage area is a cache, a database or a memory hash table.

In another aspect, the present invention provides a tile map system comprising a server, a database, and a tile generation module, the server configured to execute instructions for:

Further, after the server calls the tile generation module, the following instructions are executed:

otherwise, executing S506;

The technical scheme provided by the invention has the following beneficial effects:

a. index information is established in the space and other attribute columns of the data, corresponding image data meeting the requirements is searched from the database according to the search conditions brought in real time and the browsing tile areas, and the purpose is achieved, and meanwhile, the performance bottleneck caused by the improvement of the data quantity is reduced;

b. for the browsed areas of other users, according to the file list corresponding to the tiles, constructing a cache key value by personalized tile parameter files, and reducing the response time of the system under the condition of meeting the requirements;

c. the mechanism of filling and returning is adopted in the tile file generation process, so that the number of files opened in the tile generation process is reduced under the condition of ensuring the display vision to be correct, the IO access of a system is reduced, and the system performance is ensured not to be limited by the data volume;

d. the personalized tile map returning mechanism based on the retrieval conditions can ensure the personalized tile browsing requirement of the user and meet the retrieval requirement of the user.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments described in the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a general flow chart of a WMTS dynamic tile map making method provided by an embodiment of the present invention;

FIG. 2 is a flow chart of tile generation provided by an embodiment of the present invention.

Detailed Description

In order that those skilled in the art will better understand the present invention, a technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in which it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention.

It should be noted that the terms "first," "second," and the like in the description and the claims of the present invention and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments of the invention described herein may be implemented in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, apparatus, article, or device that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed or inherent to such process, method, article, or device.

In one embodiment of the present invention, there is provided a WMTS dynamic tile map making method based on search conditions, executed by a tile map system including a database and a tile generation module, see fig. 1, the WMTS dynamic tile map making method including the steps of:

firstly, a video map information database is pre-created, secondly, a target video is searched in the pre-created video map information database according to search conditions, the tile map data is uniquely encoded according to a target video list and personalized tile browsing parameters (tile formats png, jpg, transparency, brightness and the like), corresponding tiles are obtained from a cache according to the unique codes, if the unique codes succeed, corresponding tile data are returned, otherwise, the tiles are generated to return to a client, and meanwhile, the generated tiles and corresponding encoding results are written into the cache so as to construct a cache key value for newly generated tile files. The following details the steps:

firstly, a pre-creating image map information database, which specifically comprises the following steps:

In this embodiment, before the image file is recorded into the database, it is further required to determine whether the image file is the image data of EPSG 4326, if yes, the image file is recorded into the database, otherwise, the external rectangle of the corresponding image is converted into the EPSG 4326 format, and then the image file after the conversion format is recorded into the database.

In addition, when new data is generated in the business production process, namely data production and processing, the image files in the new data and the corresponding auxiliary information are input into the database.

Secondly, database retrieval operation, which specifically comprises:

s1, performing service access on a pre-created image map information database, and taking an incoming map browsing parameter as a retrieval condition, wherein the retrieval condition comprises: the hierarchy (Z), the line number (X) and the column number (Y) of the tile request calculate the corresponding range and the attribute condition (one or more of image auxiliary information defined when the image map information database is pre-created) of the expansion of the image file.

As described above, the auxiliary information category of the image raster data includes one or more of file path, affine transformation information, space information, coordinate system information, satellite type, sensor type, product type, shooting time, production department information, and arrangement mode; thus, service access is performed with parameters that are passed into one or more of the categories described above.

And S2, searching and obtaining a target image data list from the image map information database according to the input searching conditions.

Specifically, for example, parameters transmitted in a request of service access have spatial information, and corresponding tile ranges are calculated according to a hierarchy (Z), a row number (X) and a column number (Y) of the request; and integrating other expansion auxiliary information, and retrieving a target Image data List image_List meeting the requirements from the system space database.

Index information is established in space and other auxiliary information of data, corresponding image data meeting requirements is searched from a database according to search conditions brought in real time and browsing tile areas, and performance bottlenecks caused by data volume improvement are reduced while the search purpose is achieved.

S3, analyzing the target image data list, and carrying out tile data coding by combining the target image data list and the personalized browsing parameters to obtain a coding result.

Specifically, the target image data list and the personalized browsing parameters include tile format, transparent color, brightness, RGB color values, etc., the file number and the personalized browsing parameters are formatted into character strings respectively, and the formatted character strings are encoded, and specifically, the formatted character strings can be encoded in an encrypted or unencrypted manner.

The encoding method may adopt a conventional encoding method, for example, file numbers in a data list are formatted into a character string a according to a sequence, personalized browsing parameters are formatted into a character string B, and unique codes tcid=md5 (z+x+y+a+b) are calculated. It should be noted that, the MD5 encoding method is only an example and is not used as a basis for limiting the protection scope of the present invention, because other encoding methods in the prior art can implement the technical scheme of the present invention.

S4, acquiring corresponding tiles from the specific storage area according to the coding result, if the acquisition is successful, directly returning the acquired tiles to the client, otherwise, executing S5-S6; wherein the specific storage area is different from the storage address of the image map information database.

As described above, if the area is actually not browsed for the first time, that is, the user has browsed the area before, or for the area that has been browsed by other users, tile information may be directly obtained in the buffer according to the unique coding result and returned;

if it is actually the first time to browse the area, S5-S6 are performed.

S5, calling a tile generation module according to the target image data list and the analysis result thereof to generate a corresponding tile.

The specific steps of calling the tile generation module to generate the corresponding tile are shown in fig. 2, and include the following steps:

s500, analyzing tile parameters and parameters of the target image data list, and initializing a tile memory structure;

s501, acquiring the number of image files of the target image data list, traversing the list to acquire image files i, initializing the i to 0, if i is smaller than the number of the files, indicating that the traversal is not finished, executing S502, otherwise, indicating that the traversal is finished, and executing S507;

s502, if the coordinate system of the image file i is inconsistent with the tile coordinate system, executing S503-S505 (for coordinate system conversion), otherwise executing S506;

Because the step S506/507 adopts a filling-in-return mechanism, redundant pictures do not need to be generated after filling is finished, the number of files opened in the tile generation process is reduced under the condition that the display vision is correct, the IO access of the system is reduced, and the system performance is ensured not to be limited by the data volume. The personalized tile map returning mechanism based on the retrieval conditions can ensure the personalized tile browsing requirement of the user and can meet the retrieval requirement of the user.

The specific storage area is a cache, a database or a memory hash table, taking the cache as an example, the steps S5-S6 generate tiles to return to the client, and write the generated tiles and corresponding coding results into the cache so as to construct a cache key value for the newly generated tile file, so that when the area browses for the next time, tile information can be directly acquired in the cache area according to the unique coding results, the efficiency of matching tiles in the cache area through the cache key value is far higher than that of searching image information in the database through expanding grid tile map parameters, and the system response time can be reduced under the condition that the search requirement is met by constructing the cache key value.

In one embodiment of the invention, a tile map system is provided, the tile map system comprising a server, a database, and a tile generation module, the server configured to execute instructions for:

otherwise, executing S506;

The embodiment of the tile map system provided by the embodiment and the WMTS dynamic tile map manufacturing method based on the search condition provided by the embodiment belong to the same conception, and the specific implementation process of the embodiment of the method is detailed in the embodiment of the method, that is, all the features in the embodiment of the WMTS dynamic tile map manufacturing method based on the search condition can be introduced into the embodiment of the tile map system by a reference way.

It is noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

The foregoing is merely exemplary of the application and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the application and are intended to be comprehended within the scope of the application.

Claims

1. A WMTS dynamic tile map production method based on search conditions, executed by a tile map system comprising a database and a tile generation module, characterized in that the WMTS dynamic tile map production method comprises the steps of:

2. The WMTS dynamic tile map production method of claim 1, wherein the step of invoking the tile generation module to generate the corresponding tile comprises:

s502, if the coordinate system of the image file i is inconsistent with the tile coordinate system, executing S503-S505, otherwise executing S506;

s504, placing the first clipping file into a memory and carrying out memory file reprojection transformation on the first clipping file so that a memory file coordinate system is consistent with a tile coordinate system;

3. The WMTS dynamic tile map production method according to claim 1, wherein S1 is preceded by pre-creating an image map information database by:

4. The WMTS dynamic tile map production method according to claim 3, wherein in step S002, before entering the image file into the database, further comprises:

5. The WMTS dynamic tile map manufacturing method according to claim 1, wherein the personalized browsing parameters include one or more of tile format, transparent color, brightness, RGB color values, the target image data list and the personalized browsing parameters are formatted into character strings, respectively, and the formatted character strings are encoded.

6. The WMTS dynamic tile map production method according to claim 5, wherein the formatted character string is encoded by encryption or non-encryption.

7. The WMTS dynamic tile map production method according to claim 1, wherein step S2 further comprises:

8. The WMTS dynamic tile map production method according to claim 1, wherein the specific storage area is a cache, a database, or a memory hash table.

9. A tile map system, comprising a server, a database, and a tile generation module, the server configured to execute instructions for:

10. The tile map system of claim 9, wherein the server, upon invoking the tile generation module, executes instructions to: