.. _MorphologicalClassification: 

MorphologicalClassification
===========================





Performs morphological convex, concave and flat classification on an input image channel

Description
-----------

This algorithm is based on the following publication:
Martino Pesaresi and Jon Alti Benediktsson, Member, IEEE: A new approach for the morphological segmentation of high resolution satellite imagery.
IEEE Transactions on geoscience and remote sensing, vol. 39, NO. 2, February 2001, p. 309-320.

This application perform the following decision rule to classify a pixel between the three classes Convex, Concave and Flat. Let :math:`f` denote the input image and :math:`\psi_{N}(f)` the geodesic leveling of :math:`f` with a structuring element of size :math:`N`. One can derive the following decision rule to classify :math:`f` into Convex (label :math:`\stackrel{\smile}{k}`), Concave (label :math:`\stackrel{\frown}{k}`) and Flat (label :math:`\bar{k}`):  
:math:`f(n) = \begin{cases} \stackrel{\smile}{k} & : f-\psi_{N}(f)>\sigma \\ \stackrel{\frown}{k} & : \psi_{N}(f)-f>\sigma \\ \bar{k} & : \mid f - \psi_{N}(f) \mid \leq \sigma \end{cases}`

The output is a labeled image (0: Flat, 1: Convex, 2: Concave)



Parameters
----------

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**Input Image** :code:`-in image` *Mandatory* |br|
The input image to be classified.

**Output Image** :code:`-out image [dtype]` *Mandatory* |br|
The output classified image with 3 different values (0: Flat, 1: Convex, 2: Concave)

**Selected Channel** :code:`-channel int` *Default value: 1* |br|
The selected channel index for input image

**Structuring Element Type** :code:`-structype [ball|cross]` *Default value: ball* |br|
Choice of the structuring element type

* **Ball** |br| 

* **Cross** |br| 



**Radius** :code:`-radius int` *Default value: 5* |br|
Radius of the structuring element (in pixels), default value is 5.

**Sigma value for leveling tolerance** :code:`-sigma float` *Default value: 0.5* |br|
Sigma value for leveling tolerance, default value is 0.5.

**Available RAM (MB)** :code:`-ram int` *Default value: 256* |br|
Available memory for processing (in MB).



Examples
--------

From the command-line:

.. code-block:: bash

    otbcli_MorphologicalClassification -in ROI_IKO_PAN_LesHalles.tif -channel 1 -structype ball -radius 5 -sigma 0.5 -out output.tif


From Python:

.. code-block:: python

	import otbApplication

	app = otbApplication.Registry.CreateApplication("MorphologicalClassification")

	app.SetParameterString("in", "ROI_IKO_PAN_LesHalles.tif")
	app.SetParameterInt("channel", 1)
	app.SetParameterString("structype","ball")
	app.SetParameterInt("radius", 5)
	app.SetParameterFloat("sigma", 0.5)
	app.SetParameterString("out", "output.tif")

	app.ExecuteAndWriteOutput()



Limitations
-----------

Generation of the morphological classification is not streamable, pay attention to this fact when setting the radius size of the structuring element.

See also
--------

| otbConvexOrConcaveClassificationFilter class