Happy New Year to all!
I want to run some r.le analyses on rasters I will create from two ortho-photo images. The newer ortho-photo is full color, so when importing into GRASS I get the three RGB bands. So I make an image group and subgroup with the three bands and I can do the clustering. However The older image is a B/W tiff, so it becomes a single grayscale raster. But the classification modules require a group with more than one band. What's the best way to handle this?
Thanks,
Micha
On Thu, Jan 1, 2009 at 4:06 PM, Micha Silver <micha@arava.co.il> wrote:
Happy New Year to all!
Happy New Year!
I want to run some r.le analyses on rasters I will create from two
[please consider r.li which way faster]
ortho-photo images. The newer ortho-photo is full color, so when importing
into GRASS I get the three RGB bands. So I make an image group and subgroup
with the three bands and I can do the clustering. However The older image
is a B/W tiff, so it becomes a single grayscale raster. But the
classification modules require a group with more than one band. What's the
best way to handle this?
Note that the i.smap module also works with single-image groups.
What means "The older image" above? It's not entirely clear to me
what you plan to do.
Markus
Markus Neteler wrote:
On Thu, Jan 1, 2009 at 4:06 PM, Micha Silver <micha@arava.co.il> wrote:
Happy New Year to all!
Happy New Year!I want to run some r.le analyses on rasters I will create from two
[please consider r.li which way faster]
Thanks for the tip.
ortho-photo images. The newer ortho-photo is full color, so when importing
into GRASS I get the three RGB bands. So I make an image group and subgroup
with the three bands and I can do the clustering. However The older image
is a B/W tiff, so it becomes a single grayscale raster. But the
classification modules require a group with more than one band. What's the
best way to handle this?
Note that the i.smap module also works with single-image groups.
OK, I'll have a look.
What means "The older image" above? It's not entirely clear to me
what you plan to do.
One set of aerial photos are from the 1950's -1960's. These are all black and white photos: single band tiff. The newer set of aerial photos are color images from 2005-2007.
The region is a "savanna" area with sparse trees and bushes. We need to compare how many trees, and their size, 50 years ago with the situation today.
Any additional pointers are most welcome. Thanks,
Micha
Markus
This mail was received via Mail-SeCure System.
On Thu, Jan 1, 2009 at 10:57 AM, Micha Silver <micha@arava.co.il> wrote:
One set of aerial photos are from the 1950's -1960's. These are all black
and white photos: single band tiff. The newer set of aerial photos are
color images from 2005-2007.
The region is a "savanna" area with sparse trees and bushes. We need to
compare how many trees, and their size, 50 years ago with the situation
today.Any additional pointers are most welcome. Thanks,
Micha
Hi Micha,
i.smap has worked well for our studies in Oak Woodland ecosystems.
Here is an example using RGB imagery:
http://casoilresource.lawr.ucdavis.edu/drupal/node/548
Dylan
Dylan Beaudette wrote:
On Thu, Jan 1, 2009 at 10:57 AM, Micha Silver <micha@arava.co.il> wrote:
One set of aerial photos are from the 1950's -1960's. These are all black
and white photos: single band tiff. The newer set of aerial photos are
color images from 2005-2007.
The region is a "savanna" area with sparse trees and bushes. We need to
compare how many trees, and their size, 50 years ago with the situation
today.Any additional pointers are most welcome. Thanks,
Micha
Hi Micha,i.smap has worked well for our studies in Oak Woodland ecosystems.
Here is an example using RGB imagery:http://casoilresource.lawr.ucdavis.edu/drupal/node/548
Dylan
Hi Dylan:
Thanks for the reminder. I had seen your excellent howto's in the past, and again I have the chance to apply one of them. I'm pleased to say that the process worked "famously".
Micha