KR100917834B1 - Method for transforming asc file to geomania gcd file - Google Patents

Abstract

The present invention relates to a method for converting a format between different grid data used in a geographic information system (GIS), and a method for converting an ASC (Ascii GRID) file into a Geomania GCD (GEOMania Cell Data) file in a general computer. It is about. That is, when a command for designating a first file to be converted and a command for selecting a second file extension to be converted is received, the input command is processed and the lower left reference point of the first file format is converted to the second file. By correcting to a file format and generating the second file using the extracted information, cost and time can be reduced in constructing spatial data that is the basis for the development of the geographic information industry.

File Conversion, ASC, GCD, Geographic Information System

Description

How to convert a .cs file to a Geomania directed file {METHOD FOR TRANSFORMING ASC FILE TO GEOMANIA GCD FILE}

The present invention relates to a method of converting a format between different grid data used in a geographic information system (GIS), and to the grid information of an ASSC (Ascii GRID Format) file, which is a grid format of ESRI, in a general computer. It's about converting a GCD file, which is a GEOMania grid data file.

Prior to the present invention, the ASC file used in the grid data exchange format of several commercial geographic information systems used in Korea and the ESRI system is not converted to the grid data file of Geomania, which is a GIS software used in Korea. There was a problem that the use of grid-type geospatial data pre-built with ASC files was impossible.

The technical problem to be solved by the present invention is to extract the data of the header part and the grid information part in the ASC file format, which is the Ascii GRID format, the header part in the GCD file format of the geomania grid data file is set And the cell value of all the rows and columns in the grid information part in the ASC file format, and converts each cell value in the grid information part of the GOM file format in the ASC file format. This is to provide a way to convert the information in the file into a GCD file.

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According to an aspect of the present invention, there is provided a method of converting a file, the method comprising: a) specifying a first file, which is an ASC file to be converted, and receiving a command for selecting a second file extension to be converted to a Geomania GCD file; ; b) computing the input command to read line-by-line information in the first file format; c) extracting header part information from the first file format by dividing each row unit information from the row unit information; d) writing information of each column in a unit row in the second file format using the extracted information; e) determining whether row-level information remains in the second file format and closing the first file if the row-level information does not remain; f) correcting the lower left reference point in the first file format to the second file format by using information of the header part of the extracted first file format; And g) generating the second file by using the extracted information, wherein the information of the header part of the first file format includes the number of grid rows, the number of columns, and the lower left reference point of the first file format. It is characterized by including the coordinates and the cell size.

As described above, the present invention is a GEOMania grid that uses a variety of geospatial data structured in ASC file, which is a grid data exchange data format used in various GIS and ESRI systems in Korea. By converting it into a GCD file, which is a data file, cost and time can be greatly reduced in constructing spatial data, which is the basis for the development of the geographic information industry.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

In describing the present invention, when it is determined that the detailed description of the related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

1 is a block diagram showing a file conversion system according to an embodiment of the present invention.

As shown, the file conversion system according to an embodiment of the present invention, the map data storage unit 101, the input unit 102, the calculation processing unit 108, the program storage unit 104, RAM (RAM, 103) and The video memory 106 and the screen display unit 107 are included.
The input unit 102 receives an ASC (Ascii GRID) file to be converted from a user through a user interface, sets a generation target Geomania GCD (GEOMania Cell Data) file, and the map data storage unit 101 maps the map data. Save it.

The arithmetic processing unit 108 processes a command input from the input unit and is in charge of arithmetic processing and control of all processes for the conversion of the ASC file stored in the map data storage unit 101.

The program storage unit 104 stores a file conversion application program based on a Geographic Information System (GIS) to which the present invention is applied.

The RAM 103 temporarily stores various result values calculated by the arithmetic processing unit 108, and the video memory 106 and the screen display unit 107 display the map file to be converted on the screen.

The map data storage unit 101 and the program storage unit 104 may be implemented as a hard disk drive (HDD), an optical disk drive (ODD), or the like.

Hereinafter, an operation of a file conversion system according to an embodiment of the present invention will be described with reference to FIG. 1.

First, an embodiment of converting an ASC file into a GCD file will be described. This embodiment is an embodiment for explaining the operation of the present invention, it can be applied to the field that can be easily implemented through the present invention.

When the user wants to convert the ASC file into a GCD file, the input unit 102 receives a command for converting the file from the user.

The file conversion refers to a case of converting an ASC file into a GCD file, for example.

When the ASC file to be converted is selected from the input unit 102 and the file extension to be converted is selected, the calculation processing unit 108 analyzes and controls the file conversion command input from the input unit 102.

The control unit 102 reads the program storage unit 104 in which the file conversion program is embedded, and activates a file conversion application program based on a geographic information system having a file conversion function. The ASC file stored in the map data storage unit 101 and selected from the input unit 102 is read, and the read ASC file is temporarily stored in the memory 103.

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The operation processor 108 analyzes the header portion of the ASC file format read in the memory 103 to determine the number of rows of grids stored in the ASC, the number of columns, coordinates of the lower left reference point, And after securing the size of the cell, it is stored in the memory (103).

After being stored in the memory 103, if the reference coordinate of the lower left reference cell of the ASC is the 'center' method, the center is reduced by reducing 50% of the cell size in the xllcenter and yllcenter coordinate values so that the reference coordinates are the same as the GCD. 'Method, and the corrected value is stored in the memory 103 again.

The operation processor 108 generates a GCD file by using the header part information of the ASC family format stored in the memory 103, and reads the unit line of the grid information part that exists after the header information in the ASC file format, and then again. It stores in the memory 103.

If two or more consecutive delimiters are found by reading the unit row information of the ASC stored in the memory 103, after correcting to one blank, which is a standard delimiter, the operation is stored in the memory 103 again.

Then, the operation processing unit reads it again, separates it as a delimiter, stores each information in the memory 103 as a one-dimensional array form, reads the unit column information of the unit row of the ASC stored in the one-dimensional array form, and The unit column information is written, and it is determined whether the unit row information to be further converted remains in the ASC file based on the number of rows in the header information in the ASC file format.

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If there is no row information, an ASC file having completed reading the conversion target information is received, and the geomania grid GCD file having completed writing of the grid information is stored in the map data storage unit 101.

The operation processor 108 stores the GCD file stored in the map data storage 101 in the video memory 106 for display on the screen display 107. The generated GCD file is displayed on the screen display unit 107.

2 is an exemplary view showing an ASC file format according to an embodiment of the present invention.

As shown, the ASC file format according to an embodiment of the present invention is largely composed of a header part and a grid (row and column) part.

The header part consists of the coordinates of the lower left reference point for the drawing, the size of the grid (Cellsize), the number of grid rows, the number of grid columns, and Nodata_Value items to distinguish invalid cell values. Has a method of designating a lower left corner of a lower left cell and a method of designating a center point of a lower left cell (xllcenter, yllcenter). The grid information part (row and column) stores value information for each grid cell.

3 is an exemplary view showing a GCD file format according to an embodiment of the present invention.

As shown, the GCD file according to an embodiment of the present invention is a grid data format that is frequently used when building a GIS grid system in various national geographic information system construction projects and national research projects and private enterprises that are implemented by governments and local governments.

The GCD file, that is, the GCD file format, is largely composed of a header part and a grid part. The header part specifies a range of grid data as left, right, top, and bottom coordinates. Information about the entire grid file, such as the size (Cellsize) and Datatype, is stored, and the GRID cell value of each row / column is stored in the grid information part.

The arithmetic processing unit 108 according to an embodiment of the present invention reads the unit row of the grid information part existing after the header part information of the ASC file from the map data storage unit 101 and stores it in the memory 103.

In the unit row information, information of all columns constituting one row in the ASC is stored, which are separated as separators.

Subsequently, the operation processor 180 reads the unit row information of the ASC stored in the memory 103 and corrects the result with one blank, which is a standard delimiter, when two or more consecutive delimiters are found, and then stores the result of the memory ( 103).

The operation processor 108 reads the result stored in the memory 103 again and separates it as an identifier (ascii code 34) and stores each information (lattice cell value) in the memory 103 in the form of a one-dimensional array.

4 is a flowchart illustrating a method of converting an ASC file into a geomania GCD file according to an embodiment of the present invention.

Hereinafter, a method of converting an ASC file into a geomania GCD file according to an embodiment of the present invention will be described in detail with reference to FIG. 4.

First, the map data storage unit 101 of FIG. 1 stores map data in the form of a file.

If a command for converting an ASC file into a Geomania GCD file is input from the user, the calculation processing unit performs initial preparation for converting the ASC file into a Geomania GCD file (step 400). The step 400 is a process of receiving a data type such as a name of a newly created GCD file, a serial number, a message asking whether to accept an input file name, an integer type short, an integer type long, a real type float, or a real type double from the user. .

When the step 400 is performed, the calculation processing unit 108 reads the header part of the ASC file selected in step 402, the number of rows of the grid, the number of columns, the lower left reference point coordinates, and the cell. The memory 103 as a storage unit is stored by securing the size of the memory 103.

If the reference coordinate of the lower left reference cell of the ASC stored in the memory 103, which is the storage unit, is “center” in step 404, the arithmetic processing unit 108 cellsize each of the xllcenter and yllcenter coordinate values such that the reference coordinate is the same as the GCD. The memory 103, which is a storage unit, is stored by correcting it in a corner "

In operation 406, the operation processor 108 generates a GCD file using the header part information in the ASC file format stored in the memory 103, which is a storage unit, and stores the GCD file in the map data storage unit 101. At this time, No_Data Value to identify the invalid cell of ASC is stored in the invalid cell distinguished value column, which is the last 56 byte empty space of GCD format header.

The left, right, top, and bottom reference coordinates, which are the generation criteria of the GCD file, are calculated and applied by the calculation processing unit 108 as the number of the bottom left reference coordinates, rows, and columns extracted from the header information in the ASC file format. In the generated GCD file format, information on each cell has not been written yet.

When the GCD file is generated in step 406, the operation processor 180 reads the unit row of the grid information part existing after the header information of the ASC file in the map data storage unit 101, and stores the memory ( 103). At this time, in the unit row information, information of all columns constituting one row in the ASC is stored, which are separated as a delimiter.

In operation 410, in operation 410, when two or more consecutive delimiters are found by reading unit row information of the ASC stored in the memory 103 as a storage unit, the operation processor 180 corrects one blank (ascii code 34) that is a standard delimiter. After performing the operation, the result is stored in the memory 103 which is a storage unit.

The operation processor 180 reads it again and separates it as an identifier (ascii code 34), and stores each piece of information (lattice cell value) in the memory 103 in the form of a one-dimensional array.

Subsequently, in operation 412, the operation processor 180 reads the unit column information of the unit row of the ASC stored in the one-dimensional array form in the memory 103, which is a storage unit, and writes the unit column information of the unit row of the GCD. At this time, even in the case of a Cell Value that matches the No_Data Value of the ASC, the No_Data Value is divided into the GCD.

When the GCD file format is written, the arithmetic processing unit 108 extracts the unit row information to be further converted based on the number of rows in the header information in the ASC file format extracted in step 110 and stored in the memory 103 which is a storage unit. It is determined whether the ASC file remains and if there is unit row information to be converted, steps 408, 410, and 412 are repeated.

If there is no more unit row information to convert, step 416 is reached (step 414). Thereafter, the arithmetic processing unit 108 closes the ASC file in step 414 when there are no more conversion target row information in the ASC file format. Thus, the geomania grid GCD file in which the grid information is written in step 418 is stored in the map data storage unit 101.

1 is a block diagram showing a file conversion system according to an embodiment of the present invention.

2 illustrates an ASC file format according to an embodiment of the present invention.

3 is an exemplary view showing a GCD file format according to an embodiment of the present invention.

4 is a flowchart illustrating a method of converting an ASC file into a geomania GCD file according to an embodiment of the present invention.

<Explanation of symbols for main parts of the drawings>

101: map data storage unit

102: input unit

103: memory

104: program storage unit

107: display unit

108: computation processing unit (CPU)

Claims (7)

delete delete delete delete In the file conversion method, a) designating a first file which is an ASC file to be converted, and receiving a command for selecting a second file extension to be converted to a geomania GCD file; b) computing the input command to read line-by-line information in the first file format; c) extracting header part information from the first file format by dividing each row unit information from the row unit information; d) writing information of each column in a unit row in the second file format using the extracted information; e) determining whether row-level information remains in the first file format and closing the first file if the row-level information does not remain; f) correcting the lower left reference point in the first file format to the second file format by using information of the header part of the extracted first file format; And g) generating the second file using the extracted information Including but not limited to: The information of the header part of the first file format may include a grid row number, a column number, a lower left reference point coordinate, and a cell size of the first file format. How to convert. delete delete

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