.. _audio_visualizer:

Audio Visualizer
=====================

The ``audiovisualizer`` components can be found in the ``tools`` tab of the supplementary vdemo.
They will open a window showing a spectral visualization of their respective live microphone data on the 4K TV.
When starting the component manually, more options are available. The scope the component uses is specified with the ``INSCOPE`` environment variable.
The ``WIDTH`` and ``HEIGHT`` of the visualization window can be given (but not changed later on by resizing the window).
The text overlay is controlled by ``TEXT``.
Sometimes, the microphone volume is too low to be properly visualized. In that case, you can use the ``VOLUME`` setting, to increase the volume, with 10 being the maximum value.
There are different ``VISUALIZER`` modules that can be used. A list of typical choices is given in the code below but ultimately depends on the ``gstreamer`` installation.
See :ref:`visualizer_audio_figures` for some examples. The code also shows the defaults currently used and the complete pipeline for full reference; as a quick overview see the following table.

+-------------------------+--------------+---------------------------------------------------------------------------------------------+
| Environment Variable    | Default      | Description                                                                                 |
+=========================+==============+=============================================================================================+
| ``INSCOPE``             | <kitchen>    | Input scope                                                                                 |
+-------------------------+--------------+---------------------------------------------------------------------------------------------+
| ``WIDTH``               | 1280         | Width of the visualizer window                                                              |
+-------------------------+--------------+---------------------------------------------------------------------------------------------+
| ``HEIGHT``              | 720          | Height of the visualizer window                                                             |
+-------------------------+--------------+---------------------------------------------------------------------------------------------+
| ``VOLUME``              | 1.0          | Volume will be increased by the square of this                                              |
+-------------------------+--------------+---------------------------------------------------------------------------------------------+
| ``VISUALIZER``          | spectrascope | Width of the visualizer window                                                              |
+-------------------------+--------------+---------------------------------------------------------------------------------------------+
| ``VIDEOCOMPONENT``      | ximagesink   | Output module (``ximagesink`` or ``xvimagesink``)                                           |
+-------------------------+--------------+---------------------------------------------------------------------------------------------+
| ``VIDEOCOMPONENTPARAM`` | 720          | Optional parameter to the output module                                                     |
+-------------------------+--------------+---------------------------------------------------------------------------------------------+
| ``TEXT``                | ␣            | Text to overlay in the bottom right corner                                                  |
+-------------------------+--------------+---------------------------------------------------------------------------------------------+


.. code-block:: bash

    #!/bin/bash

    : ${GST_DEBUG:=2}
    export GST_DEBUG
    : ${INSCOPE:=/citec/csra/home/hallway/entrance/asc10/audio/in/default}
    : ${WIDTH:=1280}
    : ${HEIGHT:=720}
    : ${VOLUME:=1.0}
    #: ${VISUALIZER:=wavescope}
    : ${VISUALIZER:=spectrascope shader=fade-and-move-down}
    #: ${VISUALIZER:=spacescope}
    #: ${VISUALIZER:=synaescope}
    #: ${VISUALIZER:=libvisual_oinksie}
    #: ${VISUALIZER:=libvisual_lv_scope}
    #: ${VISUALIZER:=libvisual_lv_analyzer}
    #: ${VISUALIZER:=libvisual_jess}
    #: ${VISUALIZER:=libvisual_jakdaw}
    #: ${VISUALIZER:=libvisual_infinite}
    #: ${VISUALIZER:=libvisual_corona}
    #: ${VISUALIZER:=libvisual_bumpscope}
    #: ${VIDEOCOMPONENT:=xvimagesink}
    : ${VIDEOCOMPONENT:=ximagesink}
    #: ${VIDEOCOMPONENTPARAM:=provide-clock=false}
    : ${TEXT:=' '}
    
    # fix for ambiguous global plugins definition
    export RSB_PLUGINS_CPP_LOAD=rsbspread
    
    gst-launch-0.10 -v  \
       rsbaudiosrc \
       "scope=$INSCOPE" \
       ! audioresample \
       ! audioconvert \
       ! volume volume=$VOLUME \
       ! volume volume=$VOLUME \
       ! $VISUALIZER \
       ! textoverlay \
       text="$TEXT" halignment=right \
       font-desc="sans,helvetica,arial 14" \
       ! "video/x-raw-rgb,width=$WIDTH,height=$HEIGHT" \
       ! autovideoconvert \
       ! "$VIDEOCOMPONENT $VIDEOCOMPONENTPARAM"
       
       
At the time of this writing, the vdemo lines used for the config were:

.. code-block:: bash

    gstaudiovisualizer,${PC_CORE_VIS},-l -x -g audio -L 2 -n -t hallwayaudiovisualizer -v TEXT=Hallway -v WIDTH=320 -v HEIGHT=240 -v VOLUME=10 -v INSCOPE=/citec/csra/home/hallway/entrance/asc10/audio/in/16bit/16000Hz/LE:
    gstaudiovisualizer,${PC_CORE_VIS},-l -x -g audio -L 2 -n -t kitchenaudiovisualizer -v TEXT=Kitchen -v WIDTH=320 -v HEIGHT=240 -v VOLUME=10 -v INSCOPE=/citec/csra/home/kitchen/assistance/asc7/audio/in/16bit/16000Hz/LE:

Some example call to the script might look like this:

.. code-block:: bash

    INSCOPE=/citec/csra/home/hallway/entrance/asc10/audio/in/default TEXT=Hallway VOLUME=2 VISUALIZER=libvisual_infinite gstaudiovisualizer


.. _visualizer_audio_figures:
       

.. figure:: /images/audiovisualizer_spectrascope.png
   :scale: 50 %
   :alt: audio visualizer screenshot

   Spectroscope visualization of the kitchen microphone.

.. figure:: /images/audiovisualizer_infinite.png
   :scale: 50 %
   :alt: audio visualizer screenshot

   Libvisual's "infinite" rendering of the kitchen microphone.

.. figure:: /images/audiovisualizer_wavescope.png
   :scale: 50 %
   :alt: audio visualizer screenshot

   Wavescope visualization of the kitchen microphone.

.. figure:: /images/audiovisualizer_synaescope.png
   :scale: 50 %
   :alt: audio visualizer screenshot

   "Synaescope" visualization of the kitchen microphone.