No Data management
^^^^^^^^^^^^^^^^^^

Manage No-Data

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

This application has two modes. The first allows building a mask of no-data pixels from the no-data flags read from the image file. The second allows updating the change the no-data value of an image (pixels value and metadata). This last mode also allows replacing NaN in images with a proper no-data value. To do so, one should activate the NaN is no-data option.

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 *ManageNoData* .

.. [#] Table: Parameters table for No Data management.

+---------------------+--------------------------+----------------------------------+
|Parameter Key        |Parameter Type            |Parameter Description             |
+=====================+==========================+==================================+
|in                   |Input image               |Input image                       |
+---------------------+--------------------------+----------------------------------+
|out                  |Output image              |Output image                      |
+---------------------+--------------------------+----------------------------------+
|usenan               |Boolean                   |Boolean                           |
+---------------------+--------------------------+----------------------------------+
|mode                 |Choices                   |Choices                           |
+---------------------+--------------------------+----------------------------------+
|mode buildmask       | *Choice*                 |Build a no-data Mask              |
+---------------------+--------------------------+----------------------------------+
|mode changevalue     | *Choice*                 |Change the no-data value          |
+---------------------+--------------------------+----------------------------------+
|mode apply           | *Choice*                 |Apply a mask as no-data           |
+---------------------+--------------------------+----------------------------------+
|mode.buildmask.inv   |Float                     |Float                             |
+---------------------+--------------------------+----------------------------------+
|mode.buildmask.outv  |Float                     |Float                             |
+---------------------+--------------------------+----------------------------------+
|mode.changevalue.newv|Float                     |Float                             |
+---------------------+--------------------------+----------------------------------+
|mode.apply.mask      |Input image               |Input image                       |
+---------------------+--------------------------+----------------------------------+
|mode.apply.ndval     |Float                     |Float                             |
+---------------------+--------------------------+----------------------------------+
|ram                  |Int                       |Int                               |
+---------------------+--------------------------+----------------------------------+
|inxml                |XML input parameters file |XML input parameters file         |
+---------------------+--------------------------+----------------------------------+
|outxml               |XML output parameters file|XML output parameters file        |
+---------------------+--------------------------+----------------------------------+

**Input image**
Input image.

**Output Image**
Output image.

**Consider NaN as no-data**
If active, the application will consider NaN as no-data values as well.

**No-data handling mode**
Allows choosing between different no-data handling options. Available choices are: 

- **Build a no-data Mask**


 - **Inside Value** : Value given in the output mask to pixels that are not no data pixels.

 - **Outside Value** : Value given in the output mask to pixels that are no data pixels.


 - **Change the no-data value**


  - **The new no-data value** : The new no-data value.


  - **Apply a mask as no-data** : Apply an external mask to an image using the no-data value of the input image


   - **Mask image** : Mask to be applied on input image (valid pixels have non null values).

   - **Nodata value used** : No Data value used according to the mask image.



**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_ManageNoData -in QB_Toulouse_Ortho_XS.tif -out QB_Toulouse_Ortho_XS_nodatamask.tif uint8 -mode.buildmask.inv 255 -mode.buildmask.outv 0

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 ManageNoData application 
	ManageNoData = otbApplication.Registry.CreateApplication("ManageNoData")

	# The following lines set all the application parameters:
	ManageNoData.SetParameterString("in", "QB_Toulouse_Ortho_XS.tif")

	ManageNoData.SetParameterString("out", "QB_Toulouse_Ortho_XS_nodatamask.tif")
	ManageNoData.SetParameterOutputImagePixelType("out", 1)

	ManageNoData.SetParameterFloat("mode.buildmask.inv", 255)

	ManageNoData.SetParameterFloat("mode.buildmask.outv", 0)

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

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

None

Authors
~~~~~~~

This application has been written by OTB-Team.

See Also
~~~~~~~~

These additional ressources can be useful for further information: 

BanMath