Reproject images to use in GeoAgro GIS

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Problem description

When you try to import projected imagery to GeoAgro GIS, the system will try to place it in the map but the coordinates will be erroneous.

GeoAgro GIS (GAGIS) displays data in a geographic coordinate system (Datum WGS84), and as for now it only supports imagery in the same Geographic Coordinate System (GCS) as the map.

Consequently, you'll have to transform these files to the appropriate GCS before importing them into GAGIS.

To learn more about Map Projections please read this Wikipedia article

Software (GAGIS version / CPlanner version / Operating System)

GAGIS Version: 2.3 beta - Review 11

Problem type (GAGIS feature, Bug, Procedure)

There are three types of Troubleshooting guides

Feature Bug Procedure
x


Solution

There are several GIS Packages to accomplish this task, here you'll find links to each package's help files for the necessary tools/procedures

ArcGIS® by ESRI®

'Project Raster', see instructions here

Erdas Imagine® by ERDAS®

'Reproject an Image', see instructions here (PDF - 1.3 Mb)

GDAL

GDAL is a Free GIS library and utilities. It's more oriented to an experienced user, with a command line interface. To reproject an image you may use the 'gdalwarp' function, see instructions here


ERDAS ViewFinder

We'll describe the process of  reprojecting an image to the appropriate GCS using a free tool from ERDAS® ViewFinder® 2.1, as it is fairly simple and straightforward.

  1. Download and install ERDAS ViewFinder 2.1 from the product's web site.
  2. Open the desired image.

    Open the image - Click here to see it full size
  3. Check it's projection information using the Tools menu > Image Information tool

    Image:Reproject_images_02.jpg
  4. Save it using the Tools menu > Save as... tool

    Image:Reproject_images_03.jpg

    This window will pop up, please fill the fields as described.
  5. Then, in the Output File Options tab, check the Change Output Projection and Change Output Pixel Size options.

    Image:Reproject_images_04.jpg

    Finally click on OK to start the process.
  6. Import the newly created image into GAGIS using the Add layer Image:GIS_gis_Edit_01_01.jpg tool, Create image layer option.