[Gdal-dev] RFC 4 - Geolocation Arrays

[Frank Warmerdam]

Folks,

A client has had a long standing requirement to access geolocation
arrays for HDF4 (specifically Modis) datasets via GDAL.  Geolocation
arrays are 2D arrays of geox and geoy values with a regular relationship
to the image bands.

A very common case is where there are extra latitude and longitude bands
associated with an image, holding the lat and long locations for each pixel.
In other cases the geox/geoy values may be in a different projection, or
may be at a reduced resolution from the actual image, or may be stored
separately from the image data.

I have prepared RFC4 in an effort to address adding geolocation array
support to GDAL in a reasonably comprehensive manner.  Currently the RFC
is still considered to be "under development", but I thought it wouldn't
hurt to put it out there for feedback from the community.

I'm also committing some of the changes it talks about, but with the
understanding that they are still provisional and might be backed out or
altered depending on what the GDAL PMC decides.

The RFC can be found at:

   http://www.gdal.org/rfc4_geolocate.html

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | President OSGF, http://osgeo.org