Alaska Satellite Facility - Distributed Active Archive Center

How to View and Geocode CEOS Data in ASF MapReady

Detail of the Blue Ridge Mountains in the recipe’s sample granule. ©JAXA/METI 2008.

Source: ASF Staff



This data recipe is for users who wish to view and geocode CEOS format files using ASF’s MapReady software. (Without these steps, users can view only a jpeg browse image included with the products.) Data in CEOS format, available through the ASF DAAC, includes Level 1 JERS, ERS-1, ERS-2 and RADARSAT- 1, as well as Level 1.5 ALOS PALSAR.

ASF uses the CEOS (Committee on Earth Observation Satellites) format to release a number of historic SAR products. The CEOS format was originally developed to create a standard file format for the remote sensing community. Inconsistencies in adoption and vagueness in the original specifications, however, led to a number of different CEOS “flavors,” of which ASF’s is one.


Materials List:

Sample granule image. Part of the Blue Ridge Mountains in Virginia. ©JAXA/METI 2008.


Download Material

    1. Download ASF MapReady
    2. Install MapReady using the Installation Wizard
    3. Download a CEOS-formatted data granule from Vertex (CEOS-formatted datasets include Level 1 JERS-1, ERS-1, ERS-2 and RADARSAT-1, as well as Level 1.5 ALOS PALSAR) or use the sample granule.
    4. Create a working directory and extract the .zip file.

View Data — Two Options

Option 1 — View Only

Note: This option simply opens the granule for closer inspection. See Option 2 for projection and conversion to GeoTIFF.

    1. Open ASF View
    2. Click the Open File… button in the sidebar
    3. In the Select File menu, change the data type to CEOS Level 1 Data Files for non-PALSAR data or to ALOS Image for PALSAR data
    4. Navigate to your working directory.
    5. Double-click an image file to open it in the View window

Hint: Press the End key on your keyboard to view the entire image.

Data type menu within the Select File window
Blue Ridge Mountains, sample granule image displayed in ASF MapReady. ©JAXA/METI 2007

Option 2 — Geocode and Export to GeoTIFF in MapReady

Note: This option creates a GIS-ready GeoTIFF in a projection of your choice.

    1. Open ASF MapReady
    2. In the Input Files section, ensure Add: is set to CEOS Level 1 and click Browse…
    3. Change the Select File menu to CEOS Level 1 Files for non-PALSAR data, or to ALOS Image for PALSAR granules, and navigate to your working directory.
    4. Double-click an image file to load it into MapReady
    5. In the General tab under Select Processing Steps, check Geocode to a Map Projection and Export to a Graphics File Format
    6. Click on the Geocode tab, and select a Map Projection.
    7. Change tabs to Export and select GeoTIFF from the Export Format: dropdown.
    8. Finally, set a Destination Folder under Output Settings and click Process All to run the Geocoding process.
ASF MapReady Input Files section
General tab with the correct processing steps for geocoding checked.
Geocode tab with UTM selected as the Map Projection
Export tab with GeoTIFF set as the Export Format