Daniel lee suggested me that the problem might be the defined region. But, as far as I know, Defined region has no impact over importing data. This is true right?
Greetings
I have imported a Raster image in GRASS 6.4.1 with r.in.gdal and now, when I import the same raster (with 6.4.2) there is a grid mistmatch (more or less a quarter pixel) from previous import to the current import. The image is the same, the Location/Mapset also the only difference is the update of GRASS. Is this expected?
Thanks
Antonio
Daniel lee suggested me that the problem might be the defined region. But, as far as I know, Defined region has no impact over importing data. This is true right?
AFAIK, not quite true. Vector data are imported “whole” with no regard to the region. But raster imports honour the current region. So only that part of the imported raster covered by the current region is imported.
Furthermore the module r.in.gdal has a flag ‘-e’ to reset the current region to the extents of the imported data, and thus importing the whole dataset.
On Wed, Mar 28, 2012 at 2:06 PM, <antonio.rocha@deimos.com.pt> wrote:
Greetings
Daniel lee suggested me that the problem might be the defined region. But,
as far as I know, Defined region has no impact over importing data. This is
true right?
Yes, r.in.gdal ignores the current region. The extents and resolution
as reported by gdalinfo for the original raster and r.info for the
imported raster must be identical.
Markus M
Thanks
Antonio
Am 27. März 2012 11:52 schrieb António Rocha <antonio.rocha@deimos.com.pt>:
Greetings
I have imported a Raster image in GRASS 6.4.1 with r.in.gdal and now, when
I import the same raster (with 6.4.2) there is a grid mistmatch (more or
less a quarter pixel) from previous import to the current import. The image
is the same, the Location/Mapset also the only difference is the update of
GRASS. Is this expected?
Thanks
Antonio
Hello Markus
So, if the same image imported in different GRASS versions to the same Location/Mapset, but it has a displacement of half pixel, it means that it was a problem in earlier version of GRASS?
Thanks
Antonio
On Wed, 28 Mar 2012 14:49:42 +0200, Markus Metz <markus.metz.giswork@googlemail.com> wrote:
On Wed, Mar 28, 2012 at 2:06 PM, <antonio.rocha@deimos.com.pt> wrote:
Greetings
Daniel lee suggested me that the problem might be the defined region. But,
as far as I know, Defined region has no impact over importing data. This is
true right?
Yes, r.in.gdal ignores the current region. The extents and resolution
as reported by gdalinfo for the original raster and r.info for the
imported raster must be identical.
Markus M
Thanks
Antonio
Am 27. März 2012 11:52 schrieb António Rocha <antonio.rocha@deimos.com.pt>:
Greetings
I have imported a Raster image in GRASS 6.4.1 with r.in.gdal and now, when
I import the same raster (with 6.4.2) there is a grid mistmatch (more or
less a quarter pixel) from previous import to the current import. The image
is the same, the Location/Mapset also the only difference is the update of
GRASS. Is this expected?
Thanks
Antonio
On Wed, Mar 28, 2012 at 3:02 PM, <antonio.rocha@deimos.com.pt> wrote:
Hello Markus
So, if the same image imported in different GRASS versions to the same
Location/Mapset, but it has a displacement of half pixel, it means that it
was a problem in earlier version of GRASS?
So far, you have mentioned only a grid mismatch between the two
imported versions. Comparing r.info of these to gdalinfo of the
original raster will tell you which version is correct.
Markus M
On Wed, 28 Mar 2012 14:49:42 +0200, Markus Metz
<markus.metz.giswork@googlemail.com> wrote:
On Wed, Mar 28, 2012 at 2:06 PM, <antonio.rocha@deimos.com.pt> wrote:
Greetings
Daniel lee suggested me that the problem might be the defined region.
But,
as far as I know, Defined region has no impact over importing data. This
is
true right?
Yes, r.in.gdal ignores the current region. The extents and resolution
as reported by gdalinfo for the original raster and r.info for the
imported raster must be identical.
Markus M
Thanks
Antonio
Am 27. März 2012 11:52 schrieb António
Rocha <antonio.rocha@deimos.com.pt>:
Greetings
I have imported a Raster image in GRASS 6.4.1 with r.in.gdal and now,
when
I import the same raster (with 6.4.2) there is a grid mistmatch (more or
less a quarter pixel) from previous import to the current import. The
image
is the same, the Location/Mapset also the only difference is the update
of
GRASS. Is this expected?
Thanks
Antonio
If Your GRASS version has changed, most likely also GDAL version has
changed. Just look into GDAL changelog for any "cell is point vs cell
is area" type changes for Your raster format.
Also - for the next time don't forget to add info about raster format
You where trying to import.
Maris.
2012. gada 28. marts 16:02 <antonio.rocha@deimos.com.pt> rakstīja:
Hello Markus
So, if the same image imported in different GRASS versions to the same
Location/Mapset, but it has a displacement of half pixel, it means that it
was a problem in earlier version of GRASS?
Thanks
Antonio
On Wed, 28 Mar 2012 14:49:42 +0200, Markus Metz
<markus.metz.giswork@googlemail.com> wrote:
On Wed, Mar 28, 2012 at 2:06 PM, <antonio.rocha@deimos.com.pt> wrote:
Greetings
Daniel lee suggested me that the problem might be the defined region.
But,
as far as I know, Defined region has no impact over importing data. This
is
true right?
Yes, r.in.gdal ignores the current region. The extents and resolution
as reported by gdalinfo for the original raster and r.info for the
imported raster must be identical.
Markus M
Thanks
Antonio
Am 27. März 2012 11:52 schrieb António
Rocha <antonio.rocha@deimos.com.pt>:
Greetings
I have imported a Raster image in GRASS 6.4.1 with r.in.gdal and now,
when
I import the same raster (with 6.4.2) there is a grid mistmatch (more or
less a quarter pixel) from previous import to the current import. The
image
is the same, the Location/Mapset also the only difference is the update
of
GRASS. Is this expected?
Thanks
Antonio