Orfeo Toolbox - Open Source Geospatial Tools: Applications in Earth Observation - page 196

-milli
<

boolean > Convert to milli reflectance (optional, off by default)

-clamp
< boolean > Clamp of reflectivity values between [0, 100] (optional, on by

default)
-rsr
<

>

Relative Spectral Response File (optional, off by default)
-atmo.aerosol
<

string

Aerosol Model [noaersol/continental/maritime/urban/desertic]
(mandatory, default value is noaersol)
-atmo.oz
<

string >

float > Ozone Amount (optional, on by default, default value is 0)

-atmo.wa
<

Water Vapor Amount (optional, on by default, default value is 2.5)
-atmo.pressure
<

float >

float > Atmospheric Pressure (optional, on by default, default value is 1030)

-atmo.opt
< float > Aerosol Optical Thickness (optional, on by default, default value is

0.2)
-atmo.aeronet
< string > Aeronet File (optional, off by default)

-radius
< int 32 > Window radius (optional, on by default, default value is 2)

-inxml
<

string > Load otb application from xml file (optional, off by default)

The information pertaining to the sensor's physical gain and bias are stored in the
metadata file provided with the satellite imagery.
For SPOT5, this file is generally called metadata.dim and the information
stored within it is an implicit requirement for the optical calibration tool. The
following code snippet demonstrates how the TOA is calculated by simply spec-
ifying the input satellite imagery (with metadata), an output image and the type
of calibration model. To demonstrate the atmospheric corrections, we will use a
SPOT5 scene covering the west of Ireland that was acquired on the 15th of July
2006 Fig. 13.2 . The closest AERONET observation station to this scene is located
at Mace Head in Co. Galway, in the west of Ireland. Unfortunately, data from this
station are only available for the years 2003 and 2004 in the AERONET database.
For this reason, and for the purposes of this example, we use data from the closest
monitoring station, which is at the Chilboton site in the south of England as a proxy.
Clearly this is not ideal, but it is sufficient for the demonstration.
To correct the imagery to the TOA, we simply type the following specifying toa
as the level. By default, OTB outputs images as floating point (32 bits), which in some
cases would be unnecessarily large. In the following example, we specify the image