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

[Andrea Peri]

Hi Anna,

many thx for your reply.
You are right.


The region is set to 30meters.

I was confused from the grass display that show me the pixel cell size
to 15meters.

Thx again.

Andrea.



2015-07-27 7:43 GMT+02:00 Anna Petrášová <kratochanna at gmail.com>:
>
> On Jul 26, 2015 12:05 PM, "Andrea Peri" <aperi2007 at gmail.com> wrote:
>>
>> 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.
>
> Is it possible your computational region is set to 30 m resolution? Try
> g.region -p. r.out.gdal respects region settings.
>>
>> Thx.
>>
>> --
>> -----------------
>> Andrea Peri
>> . . . . . . . . .
>> qwerty àèìòù
>> -----------------
>> _______________________________________________
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>> grass-user at lists.osgeo.org
>> http://lists.osgeo.org/mailman/listinfo/grass-user



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