Superimpose - 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 Name                    |Parameter Type            |
+=======================+==================================+==========================+
|inr                    |Reference input                   |Input image               |
+-----------------------+----------------------------------+--------------------------+
|inm                    |The image to reproject            |Input image               |
+-----------------------+----------------------------------+--------------------------+
|elev                   |Elevation management              |Group                     |
+-----------------------+----------------------------------+--------------------------+
|elev.dem               |DEM directory                     |Directory                 |
+-----------------------+----------------------------------+--------------------------+
|elev.geoid             |Geoid File                        |Input File name           |
+-----------------------+----------------------------------+--------------------------+
|elev.default           |Default elevation                 |Float                     |
+-----------------------+----------------------------------+--------------------------+
|lms                    |Spacing of the deformation field  |Float                     |
+-----------------------+----------------------------------+--------------------------+
|fv                     |Fill Value                        |Float                     |
+-----------------------+----------------------------------+--------------------------+
|out                    |Output image                      |Output image              |
+-----------------------+----------------------------------+--------------------------+
|mode                   |Mode                              |Choices                   |
+-----------------------+----------------------------------+--------------------------+
|mode default           |Default mode                      | *Choice*                 |
+-----------------------+----------------------------------+--------------------------+
|mode phr               |Pleiades mode                     | *Choice*                 |
+-----------------------+----------------------------------+--------------------------+
|interpolator           |Interpolation                     |Choices                   |
+-----------------------+----------------------------------+--------------------------+
|interpolator bco       |Bicubic interpolation             | *Choice*                 |
+-----------------------+----------------------------------+--------------------------+
|interpolator nn        |Nearest Neighbor interpolation    | *Choice*                 |
+-----------------------+----------------------------------+--------------------------+
|interpolator linear    |Linear interpolation              | *Choice*                 |
+-----------------------+----------------------------------+--------------------------+
|interpolator.bco.radius|Radius for bicubic interpolation  |Int                       |
+-----------------------+----------------------------------+--------------------------+
|ram                    |Available RAM (Mb)                |Int                       |
+-----------------------+----------------------------------+--------------------------+
|inxml                  |Load otb application from xml file|XML input parameters file |
+-----------------------+----------------------------------+--------------------------+
|outxml                 |Save otb application to xml 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.

**Fill Value**: Fill value for area outside the reprojected image.

**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 controlling 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 artifacts.

- **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.