The window :guilabel:`Spectral Signature Plot` includes several functions for
displaying spectral signature values as a function of wavelength
(defined in the :ref:`band_set_tab`).
Signatures can be added to the Spectral Signature Plot through
the :ref:`SCP_dock`.
Overlapping signatures (belonging to different classes or macroclasses) are
highlighted in orange in the table :ref:`signature_list_plot`;
the overlapping check is performed considering :guilabel:`MC ID` or
:guilabel:`C ID` according to the setting :guilabel:`Use` 
:guilabel:`MC ID` :guilabel:`C ID` in :ref:`classification_tab`.
Overlapping signatures sharing the same :guilabel:`ID` are not highlighted.
The :guilabel:`Signature list` is a table that includes the spectral signatures added from the :ref:`SCP_dock`.
| S | MC ID | MC Name | C ID | C Name | Color |
|---|---|---|---|---|---|
| checkbox field; if checked, the spectral signature is displayed in the plot | signature Macroclass ID | signature Macroclass Name | signature Class ID | signature Class Name | signature color; also, the combination :guilabel:`MC ID`-:guilabel:`C ID` is displayed in case of overlap with other signatures |
The following tools are available.
| Tool symbol and name | Description |
|---|---|
 |
remove highlighted signatures from this list |
 |
add highlighted spectral signatures to :ref:`ROI_list` |
 |
calculate the spectral distances of spectral signatures displayed in the plot; distances are reported in the tab :ref:`spectral_distances` |
Left click and hold inside the plot to move the view of the plot. Use the mouse wheel to zoom in and out the view of the plot. Right click and hold inside the plot to zoom in a specific area of the plot. Legend inside the plot can be moved using the mouse.
The following tools are available.
| Tool symbol and name | Description |
|---|---|
 |
automatically fit the plot to data |
 |
save the plot image to file (available formats are .jpg, .png,
and .pdf) |
| :guilabel:`Plot value range` |
if checked, plot the value range for each signature with a semi-transparent area |
| :guilabel:`Band lines` |
if checked, display a vertical line for each band (center wavelength) |
| :guilabel:`Grid` |
if checked, display a grid |
:guilabel:`Max characters`  |
set the maximum length of text in the legend |
| :guilabel:`x y` | display x y coordinates of mouse cursor inside the plot |
Display the details about spectral signatures (i.e. Wavelength, Values, and Standard deviation). In case of signatures calculated from ROIs, the ROI size (number of pixels) is also displayed.
Display spectral distances of signatures (see :ref:`signature_list_plot`), which are useful for assessing ROI separability (see :ref:`spectral_distance_definition`).
- The following spectral distances are calculated :
- :ref:`spectral_angle`: range [0 = identical, 90 = different]; useful in particular for :ref:`spectra_angle_mapping_algorithm` classifications
- :ref:`euclidean_distance`: useful in particular for :ref:`minimum_distance_algorithm` classifications
- :ref:`Bray_Curtis_similarity`: range [0 = different, 100 = identical]; useful in general
Values are displayed in red if signatures are particularly similar.
