.. _gradients:

***************
Color Gradients
***************


Overview
========

A number of pre-defined color gradients are available for gempa modules.
These gradients can be used when displaying color-coded values such as grids,
spectrograms or heat-maps. The following is an overview of pre-defined
gradients along with the name of the gradient which can be used in
configurations. The gradients are grouped into:

* :ref:`gradients-fullspectrum`
* :ref:`gradients-darkyellow`
* :ref:`gradients-blackandwhite`
* :ref:`gradients-singlecolor`
* :ref:`gradients-threecolor`


List of Gradients
=================

.. _gradients-fullspectrum:

Full spectrum
-------------

Gradients that use the full spectrum of colors.


.. _gradients-default:

Default
~~~~~~~

* Configuration name: :option:`Default`

.. figure:: media/gradients/Default.*
   :width: 420 px
   :alt: overview of the Default color-gradient
.. figure:: media/gradients/Default_.*
   :width: 420 px
   :alt: example spectrogram using the Default gradient

   Example spectrogram using the "Default" color-gradient.


.. _gradients-spectrum:

Spectrum
~~~~~~~~

* Configuration name: :option:`Spectrum`

.. figure:: media/gradients/Spectrum.*
   :width: 420 px
   :alt: overview of the Spectrum color-gradient
.. figure:: media/gradients/Spectrum_.*
   :width: 420 px
   :alt: example spectrogram using the Spectrum gradient

   Example spectrogram using the "Spectrum" color-gradient.


.. _gradients-circle:

Circle
~~~~~~

* Configuration name: :option:`Circle`

.. figure:: media/gradients/Circle.*
   :width: 420 px
   :alt: overview of the Circle color-gradient
.. figure:: media/gradients/Circle_.*
   :width: 420 px
   :alt: example spectrogram using the Circle gradient

   Example spectrogram using the "Circle" color-gradient.


.. _gradients-darkyellow:

Dark to yellow
--------------

Gradients optically resembling fire with increased energy beeing displayed by
bright yellow tones.


.. _gradients-blackbody:

BlackBody
~~~~~~~~~
* Configuration name: :option:`BlackBody`

.. figure:: media/gradients/BlackBody.*
   :width: 420 px
   :alt: overview of the BlackBody color-gradient
.. figure:: media/gradients/BlackBody_.*
   :width: 420 px
   :alt: example spectrogram using the BlackBody gradient

   Example spectrogram using the "BlackBody" color-gradient.


.. _gradients-inferno:

Inferno
~~~~~~~
* Configuration name: :option:`Inferno`

.. figure:: media/gradients/Inferno.*
   :width: 420 px
   :alt: overview of the Inferno color-gradient
.. figure:: media/gradients/Inferno_.*
   :width: 420 px
   :alt: example spectrogram using the Inferno gradient

   Example spectrogram using the "Inferno" color-gradient.


.. _gradients-plasma:

Plasma
~~~~~~

* Configuration name: :option:`Plasma`

.. figure:: media/gradients/Plasma.*
   :width: 420 px
   :alt: overview of the Plasma color-gradient
.. figure:: media/gradients/Plasma_.*
   :width: 420 px
   :alt: example spectrogram using the Plasma gradient

   Example spectrogram using the "Plasma" color-gradient.


.. _gradients-blackandwhite:

Black and white
---------------

For a maximum contrast there are these two gradients that just use black and
white.


.. _gradients-blackwhite:

BlackWhite
~~~~~~~~~~

* Configuration name: :option:`BlackWhite`

.. figure:: media/gradients/BlackWhite.*
   :width: 420 px
   :alt: overview of the BlackWhite color-gradient
.. figure:: media/gradients/BlackWhite_.*
   :width: 420 px
   :alt: example spectrogram using the BlackWhite gradient

   Example spectrogram using the "BlackWhite" color-gradient.


.. _gradients-whiteblack:

WhiteBlack
~~~~~~~~~~

* Configuration name: :option:`WhiteBlack`

.. figure:: media/gradients/WhiteBlack.*
   :width: 420 px
   :alt: overview of the WhiteBlack color-gradient
.. figure:: media/gradients/WhiteBlack_.*
   :width: 420 px
   :alt: example spectrogram using the WhiteBlack gradient

   Example spectrogram using the "WhiteBlack" color-gradient.


.. _gradients-singlecolor:

Single color
------------

The single color gradients have the same benefit as the
:ref:`black and white gradients <gradients-blackwhite>` and are of a high contrast.


.. _gradients-bluepurple:

BluePurple
~~~~~~~~~~

* Configuration name: :option:`BuPu`

.. figure:: media/gradients/BluePurple.*
   :width: 420 px
   :alt: overview of the BluePurple color-gradient
.. figure:: media/gradients/BluePurple_.*
   :width: 420 px
   :alt: example spectrogram using the BluePurple gradient

   Example spectrogram using the "BluePurple" color-gradient.


.. _gradients-blues:

Blues
~~~~~

* Configuration name: :option:`Blues`

.. figure:: media/gradients/Blues.*
   :width: 420 px
   :alt: overview of the Blues color-gradient
.. figure:: media/gradients/Blues_.*
   :width: 420 px
   :alt: example spectrogram using the Blues gradient

   Example spectrogram using the "Blues" color-gradient.


.. _gradients-purplered:

PurpleRed
~~~~~~~~~

* Configuration name: :option:`PuRd`

.. figure:: media/gradients/PurpleRed.*
   :width: 420 px
   :alt: overview of the PurpleRed color-gradient
.. figure:: media/gradients/PurpleRed_.*
   :width: 420 px
   :alt: example spectrogram using the PurpleRed gradient

   Example spectrogram using the "PurpleRed" color-gradient.


.. _gradients-threecolor:

Three color
-----------

Gradients allowing to distinguish more details than
:ref:`single colored <gradients-singlecolor>`.


.. _gradients-redyellowblue:

RedYellowBlue
~~~~~~~~~~~~~

* Configuration name: :option:`RdYlBu`

.. figure:: media/gradients/RedYellowBlue.*
   :width: 420 px
   :alt: overview of the RedYellowBlue color-gradient
.. figure:: media/gradients/RedYellowBlue_.*
   :width: 420 px
   :alt: example spectrogram using the RedYellowBlue gradient

   Example spectrogram using the "RedYellowBlue" color-gradient.


.. _gradients-parula:

Parula
~~~~~~

* Configuration name: :option:`Parula`

.. figure:: media/gradients/Parula.*
   :width: 420 px
   :alt: overview of the Parula color-gradient
.. figure:: media/gradients/Parula_.*
   :width: 420 px
   :alt: example spectrogram using the Parula gradient

   Example spectrogram using the "Parula" color-gradient.


.. _gradients-viridis:

Viridis
~~~~~~~

* Configuration name: :option:`Viridis`

.. figure:: media/gradients/Viridis.*
   :width: 420 px
   :alt: overview of the Viridis color-gradient
.. figure:: media/gradients/Viridis_.*
   :width: 420 px
   :alt: example spectrogram using the Viridis gradient

   Example spectrogram using the "Viridis" color-gradient.
