[GRASS-dev] Re: [GRASSGUI] Adding a Raster Group as layer

GRASS GIS GRASS GIS developer
,
1

Yann,

It sounds like what you are suggesting is to create a GUI module that would
open a group and use various GRASS commands to do something with it--display
it, PCA, colors, etc. Kind of a comprehensive imaging module. This is a nice
idea. Once we have the main functionality done in wxgrass, it would be worth
considering how to build (or someone else can start on it now).

Michael

On 5/23/07 12:04 AM, "Yann" <yann.chemin@gmail.com> wrote:

Hello Michael,

I cannot confirm now, but some times back i was told so about the automatic
creation of a group when importing a multi-band image file with r.in.gdal.

But this is not the main issue here, once we do have a group it would be nice
to load it and
1-select any layer or any three layers and press display, it could understand
load a single layer or a d.rgb triplet.
2-various color enhancements could be synchronized/automatized indeed (i.e.
auto: grey all layers in this group, auto: transparency 30% for all layers,
auto: r.null setnull value=0 for all layers, ...).

there are few other things that can be simplified/synchronized through that
menu (pca and other functions that input a large number of files, this could
be simplified if they are already selected).

Yann

On Wednesday 23 May 2007 13:36, you wrote:

Evening Yann,

On 5/22/07 10:40 PM, "Yann" <yann.chemin@gmail.com> wrote:

After importing a multispectral image with r.in.gdal, a group is created
holding all these layers.

I don't follow you on this. What kind of group? AFAIK, r.in.gdal just
creates a set of separate raster files with identical prefixed names. Does
it build an image group?

Could we have a button that would show/select/load any existing group in
the GUI (it could have a tree inside for all the bands available).

Once loaded we could select one or any combination of 3 bands for
display.

Putting the maps in separate layers would simply overlay one on top of the
other, not recombine them into an RGB image again. This would have to take
place within d.rgb.

Following your idea, an enhanced d.rgb would be able to load a group, in
addtion to just any individual layer, making layer selection more
convenient for bands of a multiband image. I'd add that it should also have
a couple of options for doing automatic equalization stretches (linear,
log, and gaussian if I want to imagine a really nice module) on the bands
before it displays them.

Michael

__________________________________________
Michael Barton, Professor of Anthropology
School of Human Evolution & Social Change
Center for Social Dynamics & Complexity
Arizona State University

phone: 480-965-6213
fax: 480-965-7671
www: http://www.public.asu.edu/~cmbarton

__________________________________________
Michael Barton, Professor of Anthropology
School of Human Evolution & Social Change
Center for Social Dynamics & Complexity
Arizona State University

phone: 480-965-6213
fax: 480-965-7671
www: http://www.public.asu.edu/~cmbarton

2

Yes Michael, that would be nice/useful.

I'd like to start, but my level is so close to NULL in that regard...
Maybe a miracle will make me speak wxPythonic.

Yann

On Wednesday 23 May 2007 22:06, Michael Barton wrote:

Yann,

It sounds like what you are suggesting is to create a GUI module that would
open a group and use various GRASS commands to do something with
it--display it, PCA, colors, etc. Kind of a comprehensive imaging module.
This is a nice idea. Once we have the main functionality done in wxgrass,
it would be worth considering how to build (or someone else can start on it
now).

Michael

On 5/23/07 12:04 AM, "Yann" <yann.chemin@gmail.com> wrote:
> Hello Michael,
>
> I cannot confirm now, but some times back i was told so about the
> automatic creation of a group when importing a multi-band image file with
> r.in.gdal.
>
> But this is not the main issue here, once we do have a group it would be
> nice to load it and
> 1-select any layer or any three layers and press display, it could
> understand load a single layer or a d.rgb triplet.
> 2-various color enhancements could be synchronized/automatized indeed
> (i.e. auto: grey all layers in this group, auto: transparency 30% for all
> layers, auto: r.null setnull value=0 for all layers, ...).
>
> there are few other things that can be simplified/synchronized through
> that menu (pca and other functions that input a large number of files,
> this could be simplified if they are already selected).
>
> Yann
>
> On Wednesday 23 May 2007 13:36, you wrote:
>> Evening Yann,
>>
>> On 5/22/07 10:40 PM, "Yann" <yann.chemin@gmail.com> wrote:
>>> After importing a multispectral image with r.in.gdal, a group is
>>> created holding all these layers.
>>
>> I don't follow you on this. What kind of group? AFAIK, r.in.gdal just
>> creates a set of separate raster files with identical prefixed names.
>> Does it build an image group?
>>
>>> Could we have a button that would show/select/load any existing group
>>> in the GUI (it could have a tree inside for all the bands available).
>>>
>>> Once loaded we could select one or any combination of 3 bands for
>>> display.
>>
>> Putting the maps in separate layers would simply overlay one on top of
>> the other, not recombine them into an RGB image again. This would have
>> to take place within d.rgb.
>>
>> Following your idea, an enhanced d.rgb would be able to load a group, in
>> addtion to just any individual layer, making layer selection more
>> convenient for bands of a multiband image. I'd add that it should also
>> have a couple of options for doing automatic equalization stretches
>> (linear, log, and gaussian if I want to imagine a really nice module) on
>> the bands before it displays them.
>>
>> Michael
>>
>> __________________________________________
>> Michael Barton, Professor of Anthropology
>> School of Human Evolution & Social Change
>> Center for Social Dynamics & Complexity
>> Arizona State University
>>
>> phone: 480-965-6213
>> fax: 480-965-7671
>> www: http://www.public.asu.edu/~cmbarton

__________________________________________
Michael Barton, Professor of Anthropology
School of Human Evolution & Social Change
Center for Social Dynamics & Complexity
Arizona State University

phone: 480-965-6213
fax: 480-965-7671
www: http://www.public.asu.edu/~cmbarton

--
Yann Chemin
Sainte-Anne d'Auray, France

3

You've already started with the menus. Python is surprisingly easy to learn.
I was recommend a book Python from Beginner to Professional, that was pretty
good. Then, get the wxpython book. wxPython is more complicated (at least
for me). But once you get the hang of it, it's pretty decent to work with
(...most of the time).

Michael

On 5/23/07 10:25 AM, "Yann" <yann.chemin@gmail.com> wrote:

Yes Michael, that would be nice/useful.

I'd like to start, but my level is so close to NULL in that regard...
Maybe a miracle will make me speak wxPythonic.

Yann

__________________________________________
Michael Barton, Professor of Anthropology
School of Human Evolution & Social Change
Center for Social Dynamics and Complexity
Arizona State University

phone: 480-965-6213
fax: 480-965-7671
www: http://www.public.asu.edu/~cmbarton