[Gdal-dev] Question about gdal_translate and the bridge/gateway

[Frank Warmerdam]

Christiansen, Kevin (Contractor) wrote:
> This does generate a (679 Megabyte) 'out.tif' file, which is indeed 15616 x
> 11136 pixels in size. Unfortunately, there is only 1000 x 1000 pixels worth
> of data in that file.  In other words, the output file looks like a 1000 x
> 1000 pixel image that was expanded / zoomed to 15616 x 11136 pixels - it's
> very, very blocky.  Note that if I use gdal_merge.py (instead of
> gdal_translate) to translate the ADRG image to GeoTiff, I get the same
> behavior.

Kevin,

I did a little experiment with some ADRG data, and I see a similar effect
to what you see.  A few notes:

  o The 1000x1000 resolution is meaningless.  It is an artifical size
    faked for the based dataset which is really just a container for the
    subimages.
  o The subimages, when imported with what should be their natural resolution
    are in fact being pulled at a much higher resolution that necessary.

  o I really don't know why.  I will try to dig into the GDAL/OGDI driver to
    figure out what is going on.  In the meantime, I would encourage you to
    file a bug report in the GDAL Bugzilla about this issue so we can use that
    bug to track the status of the problem.

Best regards,
-- 
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