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+.. _Doc_Mensia_AdvViz:
+ 
+Advanced Visualization
+======================
+
+ General information on the Advanced Visualization Toolset:
+
+  - :ref:`Doc_Mensia_AdvViz_Generalities` : generalities about the toolset.
+  - :ref:`Doc_Mensia_AdvViz_Concepts` : understanding the Toolset design and the different visualization paradigms.
+  - :ref:`Doc_Mensia_AdvViz_Configuration` : how to configure the Advanced Visualization boxes.
+  - :ref:`Doc_Mensia_AdvViz_UseCases` : concrete examples of use, from spectral analysis to ERP display.
+
+
+.. _Doc_Mensia_AdvViz_Generalities:
+ 
+Generalities
+------------
+
+To be able to use all the features in the Mensia Advanced Visualization
+Toolset, please verify that your setup meets the following recommendations.
+
+OpenGL OpenGL dependency
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+The Toolset relies on the `OpenGL <http://www.opengl.org>`_ library
+for every rendering operations, from signal display to 3D reconstruction. You
+must ensure that your computer is equipped with an OpenGL-compatible graphic
+card or chipset. This should be the case on any recent computer.
+
+You should also ensure that your graphic card drivers are up-to-date. Please
+refer to the manufacturer website for more information.
+
@@ -0,0 +1,263 @@
+.. _Doc_Mensia_AdvViz_Concepts:
+  
+Concepts
+========
+
+
+.. _Doc_Mensia_AdvViz_Concepts_Intro:
+
+Introduction
+------------
+
+
+The **Mensia Advanced Visualization Toolset** is a collection of boxes
+dedicated to the visualization of the result of electrophysiological signal
+analysis, and are especially suitable for the **real-time analysis of EEG
+signals**, from raw signal display to 3D source reconstruction.
+  
+It addresses many different use-cases among users. Neurophysiologists can
+observe accurately in real-time **spatial and temporal patterns** in the brain
+activity (motor activity, cognitive processes). EEG signal processing
+specialists can **evaluate and compare** instantly algorithms effects
+(source separation, denoising techniques). BCI researchers can study how their
+ERP-based system may be tuned to elicit and detect the best brain response.
+  
+  
+.. figure:: images/designer-box-list.png 
+   :align: center
+
+   Simple integration in the graphical user interface
+ 
+.. _Doc_Mensia_AdvViz_Concepts_VisualizationParadigms:
+
+Visualization paradigms
+-----------------------
+
+This Toolset has been designed to be very versatile. The main design concept
+revolves around the data presentation. You basically want to display matrices
+of numbers which may have temporal, and/or spatial meanings. The most adapted
+data presentation may vary from one case to another, according to the type of
+events or patterns on which you need to get a good contrast.
+  
+Before choosing the right visualization box, ask yourself:
+
+- How do I want my data to be displayed? curves? levels?
+- What will be the best way to **enhance the contrast** between the information I want to extract and the rest of the data ?
+- Is my data stream **continuous** in time? or am I dealing with discontinuous epochs (e.g. ERPs) ?
+  
+To be adapted in most situation, the Mensia Advanced Visualization Toolset has
+been designed to cover different visualization paradigms. Take a look at all
+the possibilities and choose what will best fit your needs.
+
+- :ref:`Doc_Mensia_AdvViz_Concepts_VisualizationParadigms_Oscilloscope`
+- :ref:`Doc_Mensia_AdvViz_Concepts_VisualizationParadigms_Bars`
+- :ref:`Doc_Mensia_AdvViz_Concepts_VisualizationParadigms_Bitmap`
+- :ref:`Doc_Mensia_AdvViz_Concepts_VisualizationParadigms_Topo`
+- :ref:`Doc_Mensia_AdvViz_Concepts_VisualizationParadigms_Reco`
+  
+You can also have a look at the :ref:`Doc_Mensia_AdvViz_UseCases` "list of use-cases", showing how each box can be used on concrete, real-life examples.
+  
+.. _Doc_Mensia_AdvViz_Concepts_VisualizationParadigms_Oscilloscope:
+
+The Oscilloscope view
+~~~~~~~~~~~~~~~~~~~~~
+
+It is the most basic paradigm, used to display temporal numerical data in the
+form of **curves** (dots linked by lines). The Oscilloscope views are all
+expecting **centered** values (i.e. distributed around 0). Hence it is advised
+to use at least one temporal filter (e.g. band passing between 2 and 40 Hz
+using a :ref:`Doc_BoxAlgorithm_TemporalFilter` box) before displaying an EEG
+signal.
+  
+Four boxes use this paradigm:
+
+- :ref:`Doc_BoxAlgorithm_ContinuousOscilloscope` box: displays continuous data from left to right on a defined horizontal scale (goes back to origin upon reaching the end of the scale), channels are displayed vertically one after another, but spikes may overlap. 
+- :ref:`Doc_BoxAlgorithm_InstantOscilloscope` box: displays each block of data received as it comes, filling all the horizontal space available.
+- :ref:`Doc_BoxAlgorithm_ContinuousMultiOscilloscope` box: same as the Continuous Oscilloscope, but every input channels are displayed along the same horizontal axis with a different color, additively.
+- :ref:`Doc_BoxAlgorithm_InstantMultiOscilloscope` box: same as the Instant Oscilloscope, but every input channels are displayed along the same horizontal axis with a different color, additively.
+   
+**Example**: raw EEG signal display.
+
+.. figure:: /boxes/images/ContinuousOscilloscope_Display.png
+   :align: center
+
+   Continuous Oscilloscope displaying 2 EEG channels  
+
+.. _Doc_Mensia_AdvViz_Concepts_VisualizationParadigms_Bars:
+
+The Bar view
+~~~~~~~~~~~~
+
+Like histograms, this paradigm can be used to display and compare **series of
+levels**. Levels are displayed one after another from left to right, within a
+**color gradient**. Channels are displayed vertically, one after another with a
+fixed interval (thus some "high" levels may overlap). With a high definition
+(i.e. a rather high frequency display), the result can be viewed as a curve
+colored below the line.
+  
+Two boxes uses this paradigm:
+
+- :ref:`Doc_BoxAlgorithm_ContinuousBars` box: displays continuous data from left to right on a defined horizontal scale (goes back to origin upon reaching the end of the scale).
+- :ref:`Doc_BoxAlgorithm_InstantBars` box: displays each block of data received as it comes, filling all the horizontal space.
+   
+**Example**: spectrum display.
+
+.. figure:: /boxes/images/InstantBars_Display.png
+   :align: center
+
+   Instant Bars displaying the signal spectrum
+   
+.. _Doc_Mensia_AdvViz_Concepts_VisualizationParadigms_Bitmap:
+
+The Bitmap view
+~~~~~~~~~~~~~~~
+
+The bitmap paradigm displays matrices of data using a color gradient. The
+result is a **2D map where each cell is given a color "bit"** .  This view
+using colors can enhance easily the constrast between 2 temporal or spatial
+patterns, as the difference between "cold" and "hot" colors is quickly caught
+by the analyst's eye.  You can even add an additional dimension by using
+**stacked bitmaps** : every time a new bitmap is received, it is placed on top
+or left to the previous one.
+  
+Four boxes uses this paradigm:
+
+- :ref:`Doc_BoxAlgorithm_ContinuousBitmap` box: displays continuous data from left to right on a defined  horizontal scale (goes back to origin upon reaching the end of the scale).
+- :ref:`Doc_BoxAlgorithm_InstantBitmap` box: displays each block of data received as it comes, filling all the horizontal space.
+- :ref:`Doc_BoxAlgorithm_StackedBitmapVertical` box: each bitmap is placed on **top** of the previous one.
+- :ref:`Doc_BoxAlgorithm_StackedBitmapHorizontal` box: each bitmap is placed **left** to the previous one.
+  
+**Example**: Time-frequency map.
+
+.. figure:: /boxes/images/StackedBitmapHorz_Display.png 
+   :align: center
+
+   Stacked Bitmap (Horizontal) displaying the result of a Time-Frequency analysis
+   
+.. _Doc_Mensia_AdvViz_Concepts_VisualizationParadigms_Topo:
+
+The Topographic view
+~~~~~~~~~~~~~~~~~~~~
+
+This paradigm adds a strong spatial constraint on the input data: each channel
+must be **labelled with an electrode name** in a defined nomenclature, such as
+the standard 10-20 system. Please see
+:ref:`Doc_Mensia_AdvViz_Concepts_ChannelLocalization` for further details.
+  
+Here again the data itself is displayed using a color gradient, mapped to a 2D or 3D model using **spherical spline interpolation**.
+
+For more details about the spherical spline interpolation, please check *F.
+Perrin, J. Pernier, O. Bertrand, J.F. Echallier, Spherical splines for scalp
+potential and current density mapping, Electroencephalography and Clinical
+Neurophysiology, Volume 72, Issue 2, February 1989, Pages 184-187*.  The 2D
+model is a planar projection of the scalp, covering the scalp roughly from the
+frontal area to the occipital area (i.e. from Fp1-Fp2 to O9-O10 sites).  The
+projection result takes the shape of a disk with a crescent growth at the back
+for the occipital region.
+   
+Three boxes uses this paradigm:
+
+- :ref:`Doc_BoxAlgorithm_2DTopography` box: maps the input (which channels are labelled in the 10-20 system standard) to a planar projection of the scalp.
+- :ref:`Doc_BoxAlgorithm_3DTopography` box: maps the input (which channels are labelled in the 10-20 system standard) to a projection on a 3D model of the scalp.
+- :ref:`Doc_BoxAlgorithm_3DCubes` box: an alternative view where each channel is represented by a 3D cube, positionned in space as the electrode would be on the 3D model. 
+
+The activity is rendered by changing the size and color of the cubes.
+  
+**Example**: Displaying the power of a specific frequency band on a 3D head model.
+
+.. figure:: /boxes/images/3DTopography_Display.png
+   :align: center
+
+   Alpha power mapped on a head model using the 3D topography
+
+.. _Doc_Mensia_AdvViz_Concepts_VisualizationParadigms_Reco:
+
+The Reconstruction view
+~~~~~~~~~~~~~~~~~~~~~~~
+
+Tomographic reconstruction algorithms offer an inside look, into the brain,
+from only surface measurements.  Several techniques exist, including the
+algorithms of the popular LORETA family which slice the brain in a stack of
+little cubes called voxels, and computes the *inverse model*, a model
+reconstructing the sources of the potentials acquired at the measurement site.
+   
+One box implements the source reconstruction view:
+
+- :ref:`Doc_BoxAlgorithm_3DTomographicVisualization` box : displays a 3D source reconstruction using 2394 colored/translucent voxels in a 3D head model. 
+
+This box expects 2394 input channels, produced by an inverse model (i.e. a spatial filter with N sensor inputs for 2394 sources outputs). This model must be tailor-made for the precise EEG setup being used (e.g. using sLORETA).
+  
+.. figure:: /boxes/images/3DTomographicVisualization_Display.png
+   :align: center
+
+   3D tomographic reconstruction using the 3D Tomographic Visualization box
+
+
+.. _Doc_Mensia_AdvViz_Concepts_ChannelLocalization:
+
+Channel localization
+~~~~~~~~~~~~~~~~~~~~
+
+Every visualization box can use the spatial information conveyed by the
+electrode naming. The channels can be positionned relatively to each other as
+long as you provide in the box settings a file containing the cartesian
+coordinates of the electrodes.  Most of the time, EEG manufacturers use the
+10-20 system as an electrode naming standard. For convenience, we provide
+within the Toolset a file compiling all the coordinates of the electrodes in
+the 10-20 system.
+  
+The cartesian coordinates of all the electrodes are computed in the 3D space, where the origin is at the center of [Fpz,Oz] and [T7,T8].
+
+- the X axis goes from the occipital lobe to the frontal lobe
+- the Y axis goes from the right temporal lobe to the left temporal lobe
+- the Z axis goes from the center of the head to the top
+  
+And as for the unit, here are some key points at the maximum of the axis:
+
+- Fpz (1,0,0)
+- Oz (-1,0,0)
+- T7 (0,1,0)
+- T8 (0,-1,0)
+- Cz (0,0,1)
+  
+The following figures illustrates the cartesian coordinates of the extended 10-20 system used in the Mensia Advanced Visualization Toolset.
+
+.. figure:: images/CartesianCoordinates1.png
+   :align: center
+
+   Cartesian coordinates of the 10-20 system, side view.
+
+.. figure:: images/CartesianCoordinates2.png
+   :align: center
+
+   Cartesian coordinates of the 10-20 system, front view.
+ 
+For more information, please see *Oostenveld, R. & Praamstra, P. (2001). The
+five percent electrode system for high-resolution EEG and ERP measurements.
+Clinical Neurophysiology, 112:713-719*
+  
+Please note that using the 10-20 system is not mandatory. To use all the Toolset features related to the spatial disposition of the electrodes, you just need to provide a file that maps electrode name with their coordinates in the space described above.
+  
+The format of this file is simple text. You must provide:
+
+- the electrode names as a list of quoted labels
+- the coordinate system labels
+- the electrode coordinates of the electrodes, in the same order as in the electrode names
+  
+For example:
+
+.. code::
+
+    [
+     	["O1" "O2" ... ]
+     	["x" "y" "z" ]
+    ]
+    [
+    	[-0.309017 -0.951057 4.48966e-011 ]
+    ]
+    [
+    	[0.309017 -0.951057 4.48966e-011 ]
+    ]
+  
+For a complete example, please look at the file provided with the Toolset (``../share/mensia/openvibe-plugins/cartesian.txt``)
+
@@ -0,0 +1,220 @@
+.. _Doc_Mensia_AdvViz_Configuration:
+
+Configuration
+=============
+
+By design, all the boxes included in the Mensia Advanced Visualization Toolset
+share a common behavior when it comes to configuring the boxes, in the scenario
+edition or during its execution.  In this section we describe the common
+configuration parameters you find when using these boxes.
+  
+.. _Doc_Mensia_AdvViz_Configuration_BoxSettings:
+
+Box settings
+------------
+
+You may encounter different settings, common to all or a subset of boxes,
+depending on the paradigms.
+
+.. _Doc_Mensia_AdvViz_Configuration_ChannelLocalization:
+
+Channel localisation
+~~~~~~~~~~~~~~~~~~~~
+
+Specify here where to find the file listing the coordinates of every electrodes
+by their names. Please see
+:ref:`Doc_Mensia_AdvViz_Concepts_ChannelLocalization` for more details.
+
+For conveniency, we provide a default file
+``${AdvancedViz_ChannelLocalisation}``
+(*../share/mensia/openvibe-plugins/cartesian.txt*) which contains the cartesian
+coordinates of all electrodes in the extended 10-20 system.  This settings is
+obviously **mandatory for the Topographic views**, but can also be useful for
+the other paradigms: at runtime, you can re-arrange the channels spatially by
+their names (from left to right hemisphere, or from front to top).  This is
+useful when dealing with dense EEG (128 or more channels), which can bring a
+new light, new contrast on a rather opaque data display.
+
+.. figure:: images/Settings_ChannelLocalisation.png
+   :align: center
+
+   Spatial reorganization on a dense signal display using a Continuous Oscillator
+
+.. _Doc_Mensia_AdvViz_Configuration_Caption:
+
+Caption
+~~~~~~~
+
+If this field is used, this label will be displayed in the window, on top of the rendering area.
+
+.. _Doc_Mensia_AdvViz_Configuration_Color:
+
+Color
+~~~~~
+
+The color gradient you want to use to display the data. You can use the color picker to chose the gradient manually, or use one of the presets.
+  
+Several presets exist in form of configuration tokens ``${AdvancedViz_ColorGradient_X}``, where X can be:
+
+- ``Matlab`` or ``Matlab_Discrete`` (as in `Matlab <http://www.mathworks.fr/products/matlab/>`_ / `BCILAB toolbox <http://sccn.ucsd.edu/wiki/BCILAB>`_)
+- ``Icon`` or ``Icon_Discrete`` (as in `ICoN <https://sites.google.com/site/marcocongedo/software/icon>`)
+- ``Elan`` or ``Elan_Discrete`` (as in `Elan <http://elan.lyon.inserm.fr/>`_)
+- ``Fire`` or ``Fire_Discrete``
+- ``IceAndFire`` or ``IceAndFire_Discrete``
+
+ The default values ``AdvancedViz_DefaultColorGradient`` or ``AdvancedViz_DefaultColorGradient_Discrete`` are equal to ``Matlab`` and ``Matlab_Discrete``.
+
+Here is an example of 2D topography rendering using these color gradients:
+
+.. figure:: images/2DTopography_ColorGradients.png
+   :align: center
+
+   The color gradient presets available, illustrated with the 2D topography
+
+.. _Doc_Mensia_AdvViz_Configuration_BoxSettings_Translucency:
+
+Translucency
+~~~~~~~~~~~~
+
+This setting expects a value between 0 and 1, where 0 is complete transparency and 1 complete opacity.
+
+The translucency parameter is very useful when dealing with overlapping rendering, i.e. when some parts of the visualizations end up on each other.
+By adding some translucency the data can still be visible, and it can also smoothen dense readings for more confort.
+
+.. figure:: images/Settings_Translucency-1-05.png
+   :align: center
+
+   Using the translucency to allow dense yet smooth EEG reading
+
+.. _Doc_Mensia_AdvViz_Configuration_BoxSettings_PositiveData:
+
+Positive data only
+~~~~~~~~~~~~~~~~~~
+
+By ticking this checkbox, you shift the vertical scale of the visualization in order to have the 0 at the bottom (no negative values will be displayed)
+
+This setting can be activated when dealing with spectral amplitude or any kind of positive-only "levels".
+
+.. figure:: images/ContinuousBars_Display.png
+   :align: center
+
+   Displaying a positive level (Global Field Power) using Continuous Bars
+
+.. _Doc_Mensia_AdvViz_Configuration_BoxSettings_Gain:
+
+Gain
+~~~~
+
+If set, all samples in the input stream are multiplied by this scalar value before display.
+This can be useful when you need to display all at once different type of data on the same relative scale, with a good contrast on every view.
+
+.. _Doc_Mensia_AdvViz_Configuration_BoxSettings_TemporalCoherence:
+
+Temporal Coherence 
+~~~~~~~~~~~~~~~~~~
+
+Tells the box whether the input stream is expected to be **Time-locked** or
+**Independent**.  In the first case the box should use a Time scale (in
+seconds, for **continuous** data), and for the second case a Matrix count
+(number of data block received, for **discontinuous** data).
+ 
+.. _Doc_Mensia_AdvViz_Configuration_BoxSettings_TimeScale:
+
+Time scale
+~~~~~~~~~~
+
+The time scale (in seconds) drives the number of values to be displayed in
+continuous or stacked views before going back to the origin.  Using a time
+scale is meaningful only when dealing with an input stream made of continuous
+epochs, e.g. signal display, time-frequency analysis.
+
+.. _ Doc_Mensia_AdvViz_Configuration_BoxSettings_MatrixCount:
+
+Matrix count
+~~~~~~~~~~~~
+
+The number of input epochs to display before going back to the origin. For
+example in stacked bitmaps this setting is the number of bitmaps to be stacked
+before going back to the bottom of the stack.
+
+An illustration for this setting would be the visualization of Event-Related
+Potentials such as P300.  In such scenario, we usually select epochs of data
+uncontinuously, e.g. by extracting 600ms of signal around a target stimulation.
+Setting the Temporal coherence parameter to *Independent* will make the
+box display every epochs one after another, without trying to use the epoch
+timings.  For example, set to *Independent* when you want to stack P300
+target trials on a bitmap view, with a matrix count equal to the number of
+trials you want to stack.
+
+.. figure:: images/StackedBitmapVert_ERPDisplay.png
+   :align: center
+
+   Using a Stacked Bitmap (Vertical) to display the 3 first xDAWN components of all 99 Target trials of a P300 session
+
+
+.. _Doc_Mensia_AdvViz_Configuration_RuntimeToolbar:
+
+Runtime Settings
+----------------
+
+This section covers the different settings available at runtime (i.e. when the
+scenario is currently beeing played).  Clicking on the **toolbar** will open-up
+the runtime visualization settings. 
+
+- **Sort Channels** : rearrange the channels **by their name** (alphabetically
+  or reversed order), or **by their position on the scalp** (left to right or
+  front to back).  This last option is possible only if the channel are named
+  according to the 10-20 system, and if you provided a channel localisation
+  file in the box settings.
+
+- **Select Channels** : Select in a list the channels you want to see in the
+  visualization window.  Use the ``Ctrl`` or ``Shift`` key to add channels to
+  your selection, ``Ctrl+a`` to select all channels.
+
+- **Show scales** : show or hide all the scales around the visualization
+  widget; allows nice snapshots.  This setting is **global**, meaning that it
+  affects all the other advanced visualization windows currently running in
+  your scenario.  Doing so preserves the widgets alignment when displaying
+  synchronized data.  This setting can be turned on or off also by a **double
+  left-click** in the visualization windows itself.
+
+- **Positive data** : this setting is a runtime duplicate of the box setting
+  *Positive data only*.  If checked, the vertical axis is shifted so
+  that 0 is at the bottom. Negative values wont be displayed.
+
+Depending on the temporal coherence selected in the box settings, you may find:
+
+- **Time scale** : this setting is a runtime duplicate of the box setting *Time scale*.
+
+- **Matrix count** : this setting is a runtime duplicate of the box setting *Matrix count*.
+
+When the visualization box implements an **Instant** paradigm for **streamed
+matrices or signal input** data, a new setting is available: 
+
+- **Epoch replay** : replays the last epoch received.
+
+Topographies also expose the ERP replay in adequat conditions.  This feature is
+**global**, meaning that the replay is performed simultaneously on every
+compatible boxes.  This allows for example on-demand replays of ERPs,
+simultaneously on a signal display and a topography.
+
+.. figure:: images/3DTopography_ERPReplay.png
+   :align: center
+
+   Using the ERP replay feature on a 3D topography to catch the spatial course of the potential
+
+.. _Doc_Mensia_AdvViz_Configuration_RuntimeControls:
+
+Runtime Controls
+----------------
+
+All the visualization boxes share common controls at runtime, for a user-friendly, natural interaction.
+Using the mouse, one can:
+
+- Maintain **right click** and move the mouse up or down to **zoom in or out on the data scale**
+- Maintain **left click** and move the mouse to **rotate** a 3D model
+- Maintain **middle click** and move the mouse to **zoom in or out on a 3D model**
+- **Double left click** in the vizualisation window to remove all the scales from the frame
+
+All these controls are **global** , meaning that if you change the scale in one visualization window, it will change the scale in every visualization windows accordingly.
+  
@@ -0,0 +1,138 @@
+.. _Doc_Mensia_AdvViz_UseCases:
+
+Use-cases
+=========
+
+We describe in this section of the documentation several use-cases, typical and
+concrete examples of EEG analysis that are enlighted by the **Mensia Advanced
+Visualization Toolset**.
+  
+.. _Doc_Mensia_AdvViz_UseCases_SignalAnalysis:
+
+EEG Signal analysis
+-------------------
+
+This detailed example uses the basic OpenViBE signal processing boxes to
+perform elementary real-time analysis, and the Mensia Advanced Visualization
+Toolset to display the results:
+
+- Raw and filtered EEG
+- Spectrum, time-frequency map
+- 2D and 3D topographies
+
+You can find this scenario in the provided sample set, the scenario file name
+is ``UseCase-1-EEG-signal-analysis.mxs``.
+
+
+.. _Doc_Mensia_AdvViz_UseCases_SignalAnalysis_Intro:
+
+Introduction
+~~~~~~~~~~~~
+
+This use-case is a simple yet concrete example of real-time EEG analysis
+usually performed with OpenViBE. The scenario covers the use of oscilloscope,
+bitmaps, bars and topographic views to display signal, spectrum, and band
+power.
+
+.. _Doc_Mensia_AdvViz_UseCases_SignalAnalysis_Scenario:
+
+The scenario
+~~~~~~~~~~~~
+
+The signal used is a **motor imagery** session, where the participant performed
+right and left hand motor imagery trials.  For more details, please refer to
+the official documentation of the OpenViBE motor-imagery bci scenarios,
+provided with the official release of the software.  We chose these data for
+demonstration purpose only as it is a file provided with the official release
+of openvibe, and should be available for you anyway.
+  
+.. _Doc_Mensia_AdvViz_UseCases_SignalAnalysis_Scenario_Filtering:
+
+Signal filtering
+^^^^^^^^^^^^^^^^
+
+We first remove artifacts using temporal filters, especially the common 50Hz
+noise coming from the electrical installation.  The EEG amplifier used for the
+record we read here is a Mindmedia NeXuS 32b, with one reference channel put on
+Nz (nose). The *Reference Channel* box applies this spatial filter to further
+remove noises.
+
+We then use a :ref:`Doc_BoxAlgorithm_ContinuousOscilloscope` to display the
+filtered signal.
+
+.. figure:: images/UseCase1_1.png
+   :align: center
+
+   Denoising the signal before display
+
+.. _Doc_Mensia_AdvViz_UseCases_SignalAnalysis_Scenario_Spectrum:
+
+Spectral analysis
+^^^^^^^^^^^^^^^^^
+
+A first pipeline computes two surface Laplacian filters around C3 and C4, the
+center of the two motor cortices.  We then compute the spectrum using FFT, up
+to 32 Hz, and display it using :ref:`Doc_BoxAlgorithm_InstantBars` (spectrum
+levels) and :ref:`Doc_BoxAlgorithm_StackedBitmapHorizontal` (time-frequency
+map).  
+
+.. figure:: images/UseCase1_2.png
+   :align: center
+
+   Spectral analysis over filtered data
+
+.. _Doc_Mensia_AdvViz_UseCases_SignalAnalysis_Scenario_Topo:
+
+Topographic display
+^^^^^^^^^^^^^^^^^^^
+
+We compute in a parallel pipeline the alpha band power, averaged over several
+epochs, and visualize it over the scalp through
+:ref:`Doc_BoxAlgorithm_2DTopography` and :ref:`Doc_BoxAlgorithm_3DTopography`.
+
+.. figure:: images/UseCase1_3.png
+   :align: center
+
+   Topographic display of the alpha band power over the scalp
+
+.. _Doc_Mensia_AdvViz_UseCases_SignalAnalysis_Result:
+
+Result
+~~~~~~
+
+Here is the online visualization when we play this scenario on the provided
+data.
+
+.. figure:: images/UseCase1_6.png
+   :align: center
+
+   Signal display
+
+.. figure:: images/UseCase1_4.png
+   :align: center
+
+   Spectrum visualization
+
+.. figure:: images/UseCase1_5.png
+   :align: center
+
+   2D and 3D Topographies
+
+.. _Doc_Mensia_AdvViz_UseCases_ERPAnalysis:
+
+Event-Related Potentials analysis
+---------------------------------
+
+This use-case is focused on the ERP extraction and visualization, applied to
+P300 speller data.  The Mensia Advanced Visualization boxes allows concurrent
+and comparative displays (e.g. target versus non-target potentials), and
+synchronized replay capabilities
+
+You can find this scenario in the provided sample set, the scenario file name
+is ``UseCase-2-ERP-analysis.mxs``.
+
+
+
+
+
+