[GRASS-user] mosaic with landsat geotiff

[Daniel Victoria]

Juan,

Have you checked if the georreferencing on those images are correct? I
was once told that the CBERS images available from INPE had only the
center point with the correct georreferencing. The rest was up to the
user. Could that be the problem you are seeing with r.patch? Don't
know if the same is true for the landsat images. Maybe someone that
uses images from INPE could shed more light into the issue.

Cheers
Daniel

On Thu, May 8, 2008 at 9:06 PM, Juan Manuel Barreneche
<jumanbar at gmail.com> wrote:
> Hi everyone, i'm a relatively new user of GRASS (version 6.2.2, 2007;
> i'm using it since july 2007) and i have the following problems:
>
> I'm trying to join different landsat5 rasters, as in a mosaic
> (imported as geotiff, and downloaded from
> http://www.dgi.inpe.br/CDSR/). [These images come labeled by the orbit
> of the satellite and the "point", which is the number of image of the
> sequence of said orbit, and are in UTM projection (resolution 30m x
> 30m)]
>
> So, my problems are:
>
> 1- With r.patch i can join images from the same orbit (eg orbit: 222,
> points: 82,83), but the resulting map is not quite right: the
> overlapping region of the images are not well positioned (i thought
> that r.patch would correct this difference). [See below for different
> orbits...]
> 2- With i.image.mosaic a can't even see the resulting raster map (just
> a blank image, even if the Query tool gives normal values in the zone
> that's expected).
>
> Also, when i try to import another map, but from a different landsat5
> orbit (223), which happens to be in a different UTM zone (-22, being
> -21 the zone of my original map) i have this output:
>
>> r.in.gdal -e 'input=/home/mastermind/Documents/Proyecto Invasiones/LANDSAT/LANDSAT_5_TM_20070602_222_082_L2_BAND1.tif' output=ejemplo
> A datum name sam69 (South_American_Datum_1969) was specified without
> transformation parameters.
> WARNING: Non-interactive mode: the GRASS default for sam69 is
>         towgs84=-57.000,1.000,-41.000.
> ERROR: Projection of dataset does not appear to match current location.
>
>       LOCATION PROJ_INFO is:
>       name: Universe Transverse Mercator
>       proj: utm
>       datum: sam69
>       towgs84: -60.0,-2.0,-41.0
>       a: 6378160
>       es: 0.006694605328567784
>       zone: 21
>       south: defined
>       no_defs: defined
>
>       Dataset PROJ_INFO is:
>       name: Universe Transverse Mercator
>       proj: utm
>       datum: sam69
>       a: 6378160
>       es: 0.006694605328567784
>       zone: 22
>       south: defined
>       no_defs: defined
>
>       ERROR: zone
>
>       You can use the -o flag to r.in.gdal to override this check and use
>       the location definition for the dataset.
>       Consider generating a new location from the input dataset using the
>       'location' parameter.
>
> I've tried with the -o flag but, not surprisingly, the imported map
> was in a completely wrong position (far to the west of my original
> map, when it was supposed to be eastwards from it). The r.patch option
> was tried also in this scenario, in vain of course.
>
> 3- I thougth of yet another option: import all these images into
> another location, which is big enough to put all others inside* , for
> which i tried r.proj, but i get this:
>
>> r.proj input=223_B location=landsat5_sriptR mapset=jmb dbase=/home/mastermind/GRASSDATA output=ejemplo2 method=nearest
> PROJ_INFO file not found for location worldclim
> ERROR: Can't get projection info of output map
>
> (something similar happens when i try using the landsat5 location as
> the destination of r.proj)
>
> so i researched and found that g.setproj would create a PROJ_INFO
> file, but i got this instead:
>> g.setproj
> XY-location cannot be projected.
>
> *a map from http://www.worldclim.org/, which "... are in geodetic
> coordinate system (not projected, i.e., 'GEOGRAPHIC' or 'LATLONG'
> system). The datum is WGS84...." and have a resolution of 30 seconds.
>
> here is some more information:
>
> My landsat5 location (again):
> projection: 1 (UTM)
> zone:       -21
> datum:      sam69
> ellipsoid:  a=6378160 es=0.006694605328567784
> north:      6651449.91031
> south:      6160670.08969
> west:       158330
> east:       827030
> nsres:      30.00060032
> ewres:      30
> rows:       16359
> cols:       22290
> cells:      364642110
>
> My system (don't think it's relevant, but anyway...):
> OS: Linux 2.6.18.2-34-default i686,
> System: openSUSE 10.2 (i586), using KDE:  3.5.5 "release 45".
> Processor (CPU): Intel(R) Pentium(R) D CPU 2.80GHz
> Speed: 2,799.90 MHz
> Total memory (RAM):  1,003.06 MB
> Free memory:  16.01 MB (+ 549.73 MB Caches)
>
> well, i hope someone can give me any help on this, i would be
> immensely grateful for it,
>
> Juan Manuel Barreneche
> Zoología de Vertebrados,
> Facultad de Ciencias,
> Universidad de la República,
> Uruguay.
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