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raster data download from Geonode

raster data download from Geonode

From:
Simone Balbo
Date:
2011-07-12 @ 16:20
Hello,

I noticed that from Geonode a raster file cannot be downloaded as GeoTiff.
This is an issue for GIS people because we are forced to download rasters as
normal images which are not georeferenced; it means that in order to use
that raster again we should georeference it with the risk of introducing
errors in the original raster accuracy.

Will it be possible in the future to download raster data as GeoTiff?

Many thanks


-- 
Simone Balbo

Environmental Engineer - PhD student
ITHACA - Information Technology for Humanitarian Assistance, Cooperation and
Action
via Pier Carlo Boggio 61 - 10138 - Torino - Italy
011 1975 1860

Re: [geonode] raster data download from Geonode

From:
Jeffrey Johnson
Date:
2011-07-12 @ 16:35
Simone,

This has come up in one of the downstream projects (TsuDAT). I did a
quick mod to add GeoTiff to the list of download types on the Layer
Info page. This was done in maps/models.py by adding GeoTiff to the
list here


https://github.com/GeoNode/geonode/blob/e91464aef4d79d93d9e8960019d676ca47982414/src/GeoNodePy/geonode/maps/models.py#L783

like this

("geotiff", _("GeoTiff"), "image/geotiff"),

Note that this will return you a 3 band RGB tiff, which is not really
appropriate for downloading DEMs and other grayscale images where you
want the actual data ... this *is* a problem for TsuDAT, but may work
for you.

Let me know if that helps,

Jeff


On Tue, Jul 12, 2011 at 9:20 AM, Simone Balbo <simone.balbo@polito.it> wrote:
> Hello,
> I noticed that from Geonode a raster file cannot be downloaded as GeoTiff.
> This is an issue for GIS people because we are forced to download rasters as
> normal images which are not georeferenced; it means that in order to use
> that raster again we should georeference it with the risk of introducing
> errors in the original raster accuracy.
> Will it be possible in the future to download raster data as GeoTiff?
> Many thanks
>
> --
> Simone Balbo
> Environmental Engineer - PhD student
> ITHACA - Information Technology for Humanitarian Assistance, Cooperation and
> Action
> via Pier Carlo Boggio 61 - 10138 - Torino - Italy
> 011 1975 1860
>

Re: [geonode] raster data download from Geonode

From:
Simone Balbo
Date:
2011-07-12 @ 19:12
Jeff,

thank you very much for the information!

I modified the maps/models.py and I have been able to download GeoTiffs
which mantain the original georeferencing: this is great for GIS people!

But once uploaded up to Geonode and then downloaded, the raster changes
spatial resolution: number of rows and columns is smaller than the original
raster. Do you have any suggestion about how to obtain exactly the same
raster as it was uploaded?

Thanks

Simone

On 12 July 2011 12:35, Jeffrey Johnson <jjohnson@opengeo.org> wrote:

> Simone,
>
> This has come up in one of the downstream projects (TsuDAT). I did a
> quick mod to add GeoTiff to the list of download types on the Layer
> Info page. This was done in maps/models.py by adding GeoTiff to the
> list here
>
>
> 
https://github.com/GeoNode/geonode/blob/e91464aef4d79d93d9e8960019d676ca47982414/src/GeoNodePy/geonode/maps/models.py#L783
>
> like this
>
> ("geotiff", _("GeoTiff"), "image/geotiff"),
>
> Note that this will return you a 3 band RGB tiff, which is not really
> appropriate for downloading DEMs and other grayscale images where you
> want the actual data ... this *is* a problem for TsuDAT, but may work
> for you.
>
> Let me know if that helps,
>
> Jeff
>
>
> On Tue, Jul 12, 2011 at 9:20 AM, Simone Balbo <simone.balbo@polito.it>
> wrote:
> > Hello,
> > I noticed that from Geonode a raster file cannot be downloaded as
> GeoTiff.
> > This is an issue for GIS people because we are forced to download rasters
> as
> > normal images which are not georeferenced; it means that in order to use
> > that raster again we should georeference it with the risk of introducing
> > errors in the original raster accuracy.
> > Will it be possible in the future to download raster data as GeoTiff?
> > Many thanks
> >
> > --
> > Simone Balbo
> > Environmental Engineer - PhD student
> > ITHACA - Information Technology for Humanitarian Assistance, Cooperation
> and
> > Action
> > via Pier Carlo Boggio 61 - 10138 - Torino - Italy
> > 011 1975 1860
> >
>



-- 
Simone Balbo

Environmental Engineer - PhD student
ITHACA - Information Technology for Humanitarian Assistance, Cooperation and
Action
via Pier Carlo Boggio 61 - 10138 - Torino - Italy
011 1975 1860

Re: [geonode] raster data download from Geonode

From:
Jeffrey Johnson
Date:
2011-07-12 @ 19:18
On Tue, Jul 12, 2011 at 12:12 PM, Simone Balbo <simone.balbo@polito.it> wrote:
> Jeff,
> thank you very much for the information!
> I modified the maps/models.py and I have been able to download GeoTiffs
> which mantain the original georeferencing: this is great for GIS people!
> But once uploaded up to Geonode and then downloaded, the raster changes
> spatial resolution: number of rows and columns is smaller than the original
> raster. Do you have any suggestion about how to obtain exactly the same
> raster as it was uploaded?

This is something that has been raised by the Risiko folks.

here https://github.com/AIFDR/riab/issues/102

and various other places.

It's something we will be looking into.

Also, see my previous mail about the WCS download links not being
provided which is the real source of this error. Im looking into that
now and will report back to the list.

Jeff


> Thanks
> Simone
>
> On 12 July 2011 12:35, Jeffrey Johnson <jjohnson@opengeo.org> wrote:
>>
>> Simone,
>>
>> This has come up in one of the downstream projects (TsuDAT). I did a
>> quick mod to add GeoTiff to the list of download types on the Layer
>> Info page. This was done in maps/models.py by adding GeoTiff to the
>> list here
>>
>>
>> 
https://github.com/GeoNode/geonode/blob/e91464aef4d79d93d9e8960019d676ca47982414/src/GeoNodePy/geonode/maps/models.py#L783
>>
>> like this
>>
>> ("geotiff", _("GeoTiff"), "image/geotiff"),
>>
>> Note that this will return you a 3 band RGB tiff, which is not really
>> appropriate for downloading DEMs and other grayscale images where you
>> want the actual data ... this *is* a problem for TsuDAT, but may work
>> for you.
>>
>> Let me know if that helps,
>>
>> Jeff
>>
>>
>> On Tue, Jul 12, 2011 at 9:20 AM, Simone Balbo <simone.balbo@polito.it>
>> wrote:
>> > Hello,
>> > I noticed that from Geonode a raster file cannot be downloaded as
>> > GeoTiff.
>> > This is an issue for GIS people because we are forced to download
>> > rasters as
>> > normal images which are not georeferenced; it means that in order to use
>> > that raster again we should georeference it with the risk of introducing
>> > errors in the original raster accuracy.
>> > Will it be possible in the future to download raster data as GeoTiff?
>> > Many thanks
>> >
>> > --
>> > Simone Balbo
>> > Environmental Engineer - PhD student
>> > ITHACA - Information Technology for Humanitarian Assistance, Cooperation
>> > and
>> > Action
>> > via Pier Carlo Boggio 61 - 10138 - Torino - Italy
>> > 011 1975 1860
>> >
>
>
>
> --
> Simone Balbo
> Environmental Engineer - PhD student
> ITHACA - Information Technology for Humanitarian Assistance, Cooperation and
> Action
> via Pier Carlo Boggio 61 - 10138 - Torino - Italy
> 011 1975 1860
>

Re: [geonode] raster data download from Geonode

From:
Jeffrey Johnson
Date:
2011-07-13 @ 06:19
Simone et al,

I did find that there was a small bug in the way in which the WCS
request was setup when preparing the download links for the Layer info
page. That was ticketed here http://dev.geonode.org/trac/ticket/998
and fixed (see ticket notes).

However, when investigating this, I did find that, as you say, the wcs
download link provided does _not_ provide an *exact* copy of the
original tiff as configured in geoserver. Like you, I found that both
the size and bounding box changed. This has been ticketed here

http://dev.geonode.org/trac/ticket/1000

... and I will be looking into it further.

Jeff

On Tue, Jul 12, 2011 at 12:18 PM, Jeffrey Johnson <jjohnson@opengeo.org> wrote:
> On Tue, Jul 12, 2011 at 12:12 PM, Simone Balbo <simone.balbo@polito.it> wrote:
>> Jeff,
>> thank you very much for the information!
>> I modified the maps/models.py and I have been able to download GeoTiffs
>> which mantain the original georeferencing: this is great for GIS people!
>> But once uploaded up to Geonode and then downloaded, the raster changes
>> spatial resolution: number of rows and columns is smaller than the original
>> raster. Do you have any suggestion about how to obtain exactly the same
>> raster as it was uploaded?
>
> This is something that has been raised by the Risiko folks.
>
> here https://github.com/AIFDR/riab/issues/102
>
> and various other places.
>
> It's something we will be looking into.
>
> Also, see my previous mail about the WCS download links not being
> provided which is the real source of this error. Im looking into that
> now and will report back to the list.
>
> Jeff
>
>
>> Thanks
>> Simone
>>
>> On 12 July 2011 12:35, Jeffrey Johnson <jjohnson@opengeo.org> wrote:
>>>
>>> Simone,
>>>
>>> This has come up in one of the downstream projects (TsuDAT). I did a
>>> quick mod to add GeoTiff to the list of download types on the Layer
>>> Info page. This was done in maps/models.py by adding GeoTiff to the
>>> list here
>>>
>>>
>>> 
https://github.com/GeoNode/geonode/blob/e91464aef4d79d93d9e8960019d676ca47982414/src/GeoNodePy/geonode/maps/models.py#L783
>>>
>>> like this
>>>
>>> ("geotiff", _("GeoTiff"), "image/geotiff"),
>>>
>>> Note that this will return you a 3 band RGB tiff, which is not really
>>> appropriate for downloading DEMs and other grayscale images where you
>>> want the actual data ... this *is* a problem for TsuDAT, but may work
>>> for you.
>>>
>>> Let me know if that helps,
>>>
>>> Jeff
>>>
>>>
>>> On Tue, Jul 12, 2011 at 9:20 AM, Simone Balbo <simone.balbo@polito.it>
>>> wrote:
>>> > Hello,
>>> > I noticed that from Geonode a raster file cannot be downloaded as
>>> > GeoTiff.
>>> > This is an issue for GIS people because we are forced to download
>>> > rasters as
>>> > normal images which are not georeferenced; it means that in order to use
>>> > that raster again we should georeference it with the risk of introducing
>>> > errors in the original raster accuracy.
>>> > Will it be possible in the future to download raster data as GeoTiff?
>>> > Many thanks
>>> >
>>> > --
>>> > Simone Balbo
>>> > Environmental Engineer - PhD student
>>> > ITHACA - Information Technology for Humanitarian Assistance, Cooperation
>>> > and
>>> > Action
>>> > via Pier Carlo Boggio 61 - 10138 - Torino - Italy
>>> > 011 1975 1860
>>> >
>>
>>
>>
>> --
>> Simone Balbo
>> Environmental Engineer - PhD student
>> ITHACA - Information Technology for Humanitarian Assistance, Cooperation and
>> Action
>> via Pier Carlo Boggio 61 - 10138 - Torino - Italy
>> 011 1975 1860
>>
>

Re: [geonode] raster data download from Geonode

From:
Jeffrey Johnson
Date:
2011-07-12 @ 19:06
Hi Simone et al,

I started to look into this today to try and solve the problem in
TsuDAT ... and it looks like it 'should' work ... as in should provide
a link to download the raster as a GeoTiff from the WCS, but something
is broken.

I've filed this as ticket #998 and will be looking into it today.

http://dev.geonode.org/trac/ticket/998

Jeff

On Tue, Jul 12, 2011 at 9:35 AM, Jeffrey Johnson <jjohnson@opengeo.org> wrote:
> Simone,
>
> This has come up in one of the downstream projects (TsuDAT). I did a
> quick mod to add GeoTiff to the list of download types on the Layer
> Info page. This was done in maps/models.py by adding GeoTiff to the
> list here
>
> 
https://github.com/GeoNode/geonode/blob/e91464aef4d79d93d9e8960019d676ca47982414/src/GeoNodePy/geonode/maps/models.py#L783
>
> like this
>
> ("geotiff", _("GeoTiff"), "image/geotiff"),
>
> Note that this will return you a 3 band RGB tiff, which is not really
> appropriate for downloading DEMs and other grayscale images where you
> want the actual data ... this *is* a problem for TsuDAT, but may work
> for you.
>
> Let me know if that helps,
>
> Jeff
>
>
> On Tue, Jul 12, 2011 at 9:20 AM, Simone Balbo <simone.balbo@polito.it> wrote:
>> Hello,
>> I noticed that from Geonode a raster file cannot be downloaded as GeoTiff.
>> This is an issue for GIS people because we are forced to download rasters as
>> normal images which are not georeferenced; it means that in order to use
>> that raster again we should georeference it with the risk of introducing
>> errors in the original raster accuracy.
>> Will it be possible in the future to download raster data as GeoTiff?
>> Many thanks
>>
>> --
>> Simone Balbo
>> Environmental Engineer - PhD student
>> ITHACA - Information Technology for Humanitarian Assistance, Cooperation and
>> Action
>> via Pier Carlo Boggio 61 - 10138 - Torino - Italy
>> 011 1975 1860
>>
>