[GRASS-user] The export r.out.gdal reduce the resolution of the result from i.fusion.hpf script

[Andrea Peri]

Hi,

Starting on grass 7.0.
I try to use the
i.fusion.hpf script to create a new panchromatic image.

Starting with a raster (from landsat) 30meters and a panchromatic 15meters.
With the i.fusion.hpf I produce a new raster at high resolution (15meters).

The verify that really it has 15m , I open it with the grass display
and measure che legth of the pixel.
Ok, it is really 15meters.

After this I try to export the new raster with the r.gdal.out.
This is the command I run:

(the LC81920302015157LGN00_B4.org_hpf at andrea is the new 15meter raster)

r.out.gdal -f --verbose input=LC81920302015157LGN00_B4.org_hpf at andrea
output=D:\temp\exported_image.tif format=GTiff type=Float64
createopt=INTERLEAVE=PIXEL,TFW=YES,PROFILE=BASELINE,COMPRESS=DEFLATE

This is the log of execution:

r.out.gdal -f --verbose input=LC81920302015157LGN00_B4.org_hpf at andrea
output=D:\temp\exported_image.tif format=GTiff type=Float64
createopt=INTERLEAVE=PIXEL,TFW=YES,PROFILE=BASELINE,COMPRESS=DEFLATE
Esportazione al tipo di dato GDAL: Float64
Checking GDAL data type and nodata value...
ERROR 6: SetColorTable() only supported for Byte or UInt16
bands in TIFF format.
Using GDAL data type <Float64>
Input raster map contains cells with NULL-value (no-data). The value
nan will be used to represent no-data values in the input map. You can
specify a nodata value with the nodata option.
Exporting raster data to GTiff format...
WARNING: Too many values, color table cut to 65535 entries
r.out.gdal completo. File <D:\temp\exported_image.tif> created.

I notice the warning for too many values.
But really I don't understand what it mean because this is a float
raster and not an integer raster.

When I go to test the new exported tif image with qgis.
I see the pixel size is now 30meters and not 15meters.

How is possibile that the r.gdal.out could reduce the resolution of the image ?

This is really uncomprensible to me.

Is this a knowed issue ?

Any help is welcome.

Thx.

-- 
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Andrea Peri
. . . . . . . . .
qwerty àèìòù
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