[GRASS-user] Processing NAIP images

[Sylvain Maillard]

Hi,

I think you can find a lot of tutorial/cours on the grass website (under
Documentation: http://grass.osgeo.org/documentation/tutorials/), on the
wiki (http://grasswiki.osgeo.org/wiki/Image_processing) and also on the
manual page (http://grass.osgeo.org/grass64/manuals/index.html). There are
usually link to the man page for every command, with everything explained ;)


for your job (identify roadways), I think you will mostly be interrested by:
- Combined radiometric/geometric (segmentation based) supervised
classification (i.gensigset, i.smap)
- i.segment (http://grass.osgeo.org/grass70/manuals/i.segment.html) working
in grass7 ...


Sylvain




2014-01-29 Pedro Camargo <veigacamargo at gmail.com>

> Thanks, Jiao!!  This helps a lot!!!
>
>
>
> Pedro
>
>
>
>
>
> *From:* Jiao Wang [mailto:jiao at hawaii.edu]
> *Sent:* Tuesday, January 28, 2014 1:02 PM
> *To:* Pedro Camargo
> *Cc:* GRASS user list
> *Subject:* Re: [GRASS-user] Processing NAIP images
>
>
>
> Hi Pedro,
>
>
>
> I did a test run and created an unsupervised classification image.
>
>
>
> Here are the steps I did:
>
>
>
> 1 MrSID to tiff in QGIS
>
> 2 import tiff in GRASS (i.in.gdal)
>
> 3 create group and subgroup (i.group ---check "Define also sub-group(same
> name as group)"--- in the "Layers in selected group" keep one band file as
> described in i.cluster manual)
>
> 4 classification --signature(i.cluster)
>
> 5 classification--map (i.maxlik)
>
>
>
> Hope it helps.
>
>
>
> Best,
>
> Jiao
>
>
>
>
>
> On Tue, Jan 28, 2014 at 9:00 AM, Pedro Camargo <veigacamargo at gmail.com>
> wrote:
>
> Hi,
>
>        I am trying to generate land use maps (looking to identify roadways
> only, actually) using NAIP imagery.
>
>        Since I am using the pre-compiled GRASS, I do not have MrSID inside
> GRASS, so converted the images to TIFF using QGIS.
>
>       I believe I can use i.maxlik or something like that, but I do not
> know how to start.  It keeps asking for groups, but I do not know what is a
> group image.
>
>
>
>     I googled a lot on this and looked into several tutorials, but still
> did not figure out how to start  this.  I have been educating myself
> through a few papers, but I guess I still need to find a good summarized
> tutorial on how to do this with multi band images such as NAIP.
>
> Does anybody have ideas to help?
>
> Thanks,
>
> Pedro
>
>
> _______________________________________________
> grass-user mailing list
> grass-user at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/grass-user
>
>
>
> _______________________________________________
> grass-user mailing list
> grass-user at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/grass-user
>
-------------- section suivante --------------
Une pi?ce jointe HTML a ?t? nettoy?e...
URL: <http://lists.osgeo.org/pipermail/grass-user/attachments/20140129/76bab98c/attachment-0001.html>