Superimpose sensor
^^^^^^^^^^^^^^^^^^

Using available image metadata, project one image onto another one

Detailed description
--------------------

This application performs the projection of an image into the geometry of another one.

Parameters
----------

This section describes in details the parameters available for this application. Table [#]_ presents a summary of these parameters and the parameters keys to be used in command-line and programming languages. Application key is *Superimpose* .

.. [#] Table: Parameters table for Superimpose sensor.

+-----------------------+--------------------------+----------------------------------+
|Parameter Key          |Parameter Type            |Parameter Description             |
+=======================+==========================+==================================+
|inr                    |Input image               |Input image                       |
+-----------------------+--------------------------+----------------------------------+
|inm                    |Input image               |Input image                       |
+-----------------------+--------------------------+----------------------------------+
|elev                   |Group                     |Group                             |
+-----------------------+--------------------------+----------------------------------+
|elev.dem               |Directory                 |Directory                         |
+-----------------------+--------------------------+----------------------------------+
|elev.geoid             |Input File name           |Input File name                   |
+-----------------------+--------------------------+----------------------------------+
|elev.default           |Float                     |Float                             |
+-----------------------+--------------------------+----------------------------------+
|lms                    |Float                     |Float                             |
+-----------------------+--------------------------+----------------------------------+
|out                    |Output image              |Output image                      |
+-----------------------+--------------------------+----------------------------------+
|mode                   |Choices                   |Choices                           |
+-----------------------+--------------------------+----------------------------------+
|mode default           | *Choice*                 |Default mode                      |
+-----------------------+--------------------------+----------------------------------+
|mode phr               | *Choice*                 |Pleiades mode                     |
+-----------------------+--------------------------+----------------------------------+
|interpolator           |Choices                   |Choices                           |
+-----------------------+--------------------------+----------------------------------+
|interpolator bco       | *Choice*                 |Bicubic interpolation             |
+-----------------------+--------------------------+----------------------------------+
|interpolator nn        | *Choice*                 |Nearest Neighbor interpolation    |
+-----------------------+--------------------------+----------------------------------+
|interpolator linear    | *Choice*                 |Linear interpolation              |
+-----------------------+--------------------------+----------------------------------+
|interpolator.bco.radius|Int                       |Int                               |
+-----------------------+--------------------------+----------------------------------+
|ram                    |Int                       |Int                               |
+-----------------------+--------------------------+----------------------------------+
|inxml                  |XML input parameters file |XML input parameters file         |
+-----------------------+--------------------------+----------------------------------+
|outxml                 |XML output parameters file|XML output parameters file        |
+-----------------------+--------------------------+----------------------------------+

**Reference input**
The input reference image.

**The image to reproject**
The image to reproject into the geometry of the reference input.

**Elevation management**
This group of parameters allows managing elevation values. Supported formats are SRTM, DTED or any geotiff. DownloadSRTMTiles application could be a useful tool to list/download tiles related to a product.

- **DEM directory:** This parameter allows selecting a directory containing Digital Elevation Model files. Note that this directory should contain only DEM files. Unexpected behaviour might occurs if other images are found in this directory.

- **Geoid File:** Use a geoid grid to get the height above the ellipsoid in case there is no DEM available, no coverage for some points or pixels with no_data in the DEM tiles. A version of the geoid can be found on the OTB website (http://hg.orfeo-toolbox.org/OTB-Data/raw-file/404aa6e4b3e0/Input/DEM/egm96.grd).

- **Default elevation:** This parameter allows setting the default height above ellipsoid when there is no DEM available, no coverage for some points or pixels with no_data in the DEM tiles, and no geoid file has been set. This is also used by some application as an average elevation value.



**Spacing of the deformation field**
Generate a coarser deformation field with the given spacing.

**Output image**
Output reprojected image.

**Mode**
Superimposition mode. Available choices are: 

- **Default mode** : Default superimposition mode : uses any projection reference or sensor model found in the images


- **Pleiades mode** : Pleiades superimposition mode, designed for the case of a P+XS bundle in SENSOR geometry. It uses a simple transform on the XS image : a scaling and a residual translation.



**Interpolation**
This group of parameters allows defining how the input image will be interpolated during resampling. Available choices are: 

- **Bicubic interpolation** : Bicubic interpolation leads to very good image quality but is slow.


 - **Radius for bicubic interpolation** : This parameter allows controling the size of the bicubic interpolation filter. If the target pixel size is higher than the input pixel size, increasing this parameter will reduce aliasing artefacts.


 - **Nearest Neighbor interpolation** : Nearest neighbor interpolation leads to poor image quality, but it is very fast.


 - **Linear interpolation** : Linear interpolation leads to average image quality but is quite fast



**Available RAM (Mb)**
Available memory for processing (in MB).

**Load otb application from xml file**
Load otb application from xml file.

**Save otb application to xml file**
Save otb application to xml file.

Example
-------

To run this example in command-line, use the following: 
::

	otbcli_Superimpose -inr QB_Toulouse_Ortho_PAN.tif -inm QB_Toulouse_Ortho_XS.tif -out SuperimposedXS_to_PAN.tif

To run this example from Python, use the following code snippet: 

::

	#!/usr/bin/python

	# Import the otb applications package
	import otbApplication

	# The following line creates an instance of the Superimpose application 
	Superimpose = otbApplication.Registry.CreateApplication("Superimpose")

	# The following lines set all the application parameters:
	Superimpose.SetParameterString("inr", "QB_Toulouse_Ortho_PAN.tif")

	Superimpose.SetParameterString("inm", "QB_Toulouse_Ortho_XS.tif")

	Superimpose.SetParameterString("out", "SuperimposedXS_to_PAN.tif")

	# The following line execute the application
	Superimpose.ExecuteAndWriteOutput()

Limitations
~~~~~~~~~~~

None

Authors
~~~~~~~

This application has been written by OTB-Team.