[GRASS-user] use of i.landsat.acca- question about band 1

GRASS GRASS user
1

Greetings

I saw in i.landsat.acca manual that this module does not use band 1 to process and identify clouds/shadow pixels. my question is related with input (band_prefix). Since my 7 LANDSAT bands use the same preffix (B.) does this module discards the use of B.1 band or I shall only have the required bands with B. preffix?

Thanks
Pedro

2

Hi,

2010/11/4 Pedro Roma <pedroroma1982@gmail.com>:

I saw in i.landsat.acca manual that this module does not use band 1 to
process and identify clouds/shadow pixels. my question is related with input
(band_prefix). Since my 7 LANDSAT bands use the same preffix (B.) does this
module discards the use of B.1 band or I shall only have the required bands
with B. preffix?

please note that I changed `band_prefix` to `input_prefix` (update you
installation). Now

`i.landsat.acca input_prefix=B.` for B.1, B.2, etc.

Martin

--
Martin Landa <landa.martin gmail.com> * http://geo.fsv.cvut.cz/~landa

3

Martin wrote

please note that I changed `band_prefix` to `input_prefix`
(update you installation). Now

`i.landsat.acca input_prefix=B.` for B.1, B.2, etc.

I see the logic, but in this case I'm not sure I agree with it,
and band_prefix= (with an assumed '.') may be the better choice.

the goal of standardization is to make it easier to understand
new modules. but in the case where a more specific name provides
more clarity of meaning, and the module is not possible to re-
purpose, then the standardized name loses its advantage.

just my 2c,
Hamish

4

Hi,

2010/11/8 Hamish <hamish_b@yahoo.com>:

please note that I changed `band_prefix` to `input_prefix`
(update you installation). Now

`i.landsat.acca input_prefix=B.` for B.1, B.2, etc.

I see the logic, but in this case I'm not sure I agree with it,
and band_prefix= (with an assumed '.') may be the better choice.

why? Without '.' it's more flexible. See tricks with r.reclass on wiki [1].

the goal of standardization is to make it easier to understand
new modules. but in the case where a more specific name provides
more clarity of meaning, and the module is not possible to re-
purpose, then the standardized name loses its advantage.

That's reason why I made this change. Now i.landsat.toar together with
i.landsat.acca are more flexible in use, see my notes about Landsat
(in Czech) [2].

Martin

[1] http://grass.osgeo.org/wiki/LANDSAT#Minimal_disk_space_copies
[2] http://geo.fsv.cvut.cz/gwiki/GRASS_GIS_-_Poznámky_pro_družicová_data_Landsat

--
Martin Landa <landa.martin gmail.com> * http://geo.fsv.cvut.cz/~landa

5

THanks Martin. So, it doesn’t matter if the module uses B.1 or not… This is managed internally right?

On Sun, Nov 7, 2010 at 9:55 AM, Martin Landa <landa.martin@gmail.com> wrote:

Hi,

2010/11/4 Pedro Roma <pedroroma1982@gmail.com>:

I saw in i.landsat.acca manual that this module does not use band 1 to
process and identify clouds/shadow pixels. my question is related with input
(band_prefix). Since my 7 LANDSAT bands use the same preffix (B.) does this
module discards the use of B.1 band or I shall only have the required bands
with B. preffix?

please note that I changed band_prefix to input_prefix (update you
installation). Now

i.landsat.acca input_prefix=B. for B.1, B.2, etc.

Martin

–
Martin Landa <landa.martin gmail.com> * http://geo.fsv.cvut.cz/~landa