5. How to convert DEM into ASCII text
From GeoMod
There are many problems which geographers and technicians face in distributing large raster files.
First, there is the large size of the files.
Second, the different data formats used by the most common proprietary and free software make the procedure really confusing.
Third, the binary representation of numbers changes depending on the hardware platform; and
Finally, there is this issue of convenience of the maintainer's research group.
ASCII overcomes these disadvantages and even excels to have the following advantages:
1. It stores data in a reasonably compact raster format when compressed with Zip,
2. It is widely supported and easy to convert with a small script if necessary,
3. It is an ASCII format so it is both human readable and hardware independent; and
4. It is easy to import and export from my GIS software (ArcGIS).
Several software packages can import data from a text format. This article explains converting a raster dataset into a text file.
The following steps should be followed to convert and ESRI GRID file to ASCII text file:
1. Open ArcMap and add the raster dataset.
2. Activate the ArcToolbox – It’s the red box in between ArcCatalog and ArcInfo Icons. It’s the only red thing on the screen when you are in ArcMap.
Location of ArcToolbox Icon
3. As soon as you activate the ArcToolbox a new window will open.
Screen Set-up while Converting Raster to ASCII
4. Click Conversion Tools > From Raster > Raster to ASCII
5. Enter the Raster file which you want to convert to ASCII and enter the output ASCII file name.
6. Click OK and the file would be created in the designated file space.
Try this out and let me know if you face any problems with this.
