[GRASS-user] no nulls outside project map area
William Kyngesburye
woklist at kyngchaos.com
Fri Jun 5 16:43:35 EDT 2009
I started with a tiff image, in Albers projection. Imported in a new
location in GRASS - the tiff region is rectangular with no nulls in
the region, so the GRASS region follows the tiff region exactly.
Then I projected to a latlong location. The tiff is off to one side
of the central meridian, so the projected image appears rotated and
stretched, as expected:
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But the the triangular areas outside the original tiff region are
white, not null. My latlong region is larger than the image - I'm
going to merge multiple tiled and overlapping tiffs - and there are
nulls outside the extents of the projected area of the image.
Is this expected behavior? I usually go from latlong to projected
location, and the source latlong region is larger than the projected
region so I don't see this.
GRASS 6.5svn
-----
William Kyngesburye <kyngchaos*at*kyngchaos*dot*com>
http://www.kyngchaos.com/
Earth: "Mostly harmless"
- revised entry in the HitchHiker's Guide to the Galaxy
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