Several transformation methods are available in the EnMAP-Box. You can find them in the Processing Toolbox under :menuselection:`EnMAP-Box --> Transformation`. The usual way to apply these methods is to use a :guilabel:`Fit ...` algorithm first and then apply it to an image with :guilabel:`Transform raster layer`.
This recipe demonstrates the basic workflow of applying transformations using a principle component analysis (:ref:`Fit PCA`) and the :ref:`test dataset <test_dataset>`.
.. seealso:: You can find all the available transformation algorithms :ref:`here <Transformation>`.
Open the test dataset
In the processing toolbox go to :menuselection:`EnMAP-Box --> Transformation --> Fit PCA`
- Specify :file:`enmap_berlin.bsq` under :guilabel:`Raster`
- Under :guilabel:`Output Transformer` specify an output file path and click :guilabel:`Run`
Now open :menuselection:`EnMAP-Box --> Transformation --> Transform raster layer`
- Select :file:`enmap_berlin.bsq` as input :guilabel:`Raster`
- Under :guilabel:`Transformer` click :guilabel:`...` and select the output :file:`.pkl` file from the Fit PCA algorithm
- Specify an output filepath for the transformed raster under :guilabel:`Transformation` and click :guilabel:`Run`
Results of a PCA transformation: input image on the upper left, RGB representation of the first 3 components on the upper right and singleband gray visualisation of the same components on the bottom.
