Page History
- What type of data does HEG work with?
- What is HDF-EOS data?
- What are SWATH and GRID HDF-EOS Objects?
- What types of data products are in HDF-EOS that work with HEG?
- Is there a list that specifies the data sets that work with HEG?
- Which platforms does HEG support?
- What language was HEG used to create HEG?
- How can I view the GeoTIFF output from HEG?
...
Q:
What type of data does HEG work with?Anchor typeOfData typeOfData
A: HEG only works with HDF-EOS formatted data.
Q:
What is HDF-EOS data?Anchor HDFEOSData HDFEOSData
A: HDF-EOS is an extension of HDF data created to work for the EOS satellites. It is made up of Objects which are of either SWATH or GRID type.
Q:
What are SWATH and GRID HDF-EOS Objects?Anchor swathGridObject swathGridObject
A: GRID Objects contain data that is in a GRID format which models a Map Projection. All Map Projections are in grids. If one knows that data is in a Map Grid, then just about all that is needed to describe the grid is the Upper Left and Lower Right Corner points and the pixel resolution. The geographic location of each data point (which corresponds to a node on the grid) can be easily converted to a geolocation point using Map Projection algorithms. (In HEG, this is done with the GCTP library). Examples of GRID HDF-EOS data sets are the MOD09GHK.
SWATH Objects contain ungridded data. For each data point, there is an associated Latitude and Longitude point. Sometimes, in order to conserve space, there are a smaller number of geolocation data points than data points. In this case, interpolations of missing geolocation data points are expected to be made, which HEG will take into account. In this case, the SWATH Object will have offset and increment information describing how the geolocation data is distributed among the actual data points themselves.
More details about HDF-EOS formats can be obtained in the following documentation:
...
Overview
Content Tools