<p class="warning">
Ardour's VBAP panner is currently in development, and its semantics may
- change in the near future, possibly affecting your mixes. Please do not
- rely on it for important production work while the dust settles.
+ change in the near future, possibly affecting mixes using it. It is advised not
+ to rely on it for important production work while the dust settles.<br/>
+ The Panner only works in fixed static mode, it does not support
+ automation playback.
</p>
<p>
- <dfn><abbr title="Vector-base Amplitude Panning">VBAP</abbr></dfn>
+ <dfn><abbr title="Vector-base Amplitude Panning">VBAP</abbr></dfn>
is a versatile and straightforward method to pan a source around over an
arbitrary number of speakers on a horizontal polygon or a 3D surface,
even if the speaker layout is highly irregular.
<h2>Basic concepts</h2>
<p>
- VBAP was developed by Ville Pulkki at Aalto University, Helsinki, in 2001.
+ VBAP was developed by Ville Pulkki at Aalto University, Helsinki, in 1997.
It works by distributing the signal to the speakers nearest to the desired
- direction with appropriate weightings, aiming to create a maximally sharp
+ direction with appropriate weightings, aiming to create a maximally sharp
phantom source by using as few speakers as possible:
</p>
<ul>
<li>and three speakers in the general 3D case.</li>
</ul>
<p>
- Thus, if you move the panner onto a speaker, you can be sure that only
- this speaker will get any signal. This is handy when you need precise
- 1:1 routing.<br>
- The drawback of VBAP is that a moving source will constantly change its
- apparent sharpness, as it transitions between the three states mentioned
- above.
+ Thus, if the panner is moved onto a speaker, only this speaker will get any
+ signal. This is handy when precise 1:1 routing is needed.
</p>
<p>
- A <dfn>horizontal</dfn> VBAP panner has one parameter, the <dfn>azimuth
- angle</dfn>. A <dfn>full-sphere</dfn> panner offers an additional
+ The drawback of VBAP is that a moving source will constantly change its
+ apparent sharpness, as it transitions between the three states mentioned above.
+</p>
+<p>
+ An <dfn>horizontal</dfn> VBAP panner has one parameter, the <dfn>azimuth
+ angle</dfn>. A <dfn>full-sphere</dfn> panner offers an additional
<dfn>elevation angle</dfn> control.
</p>
<p class="note">
More elaborate implementations of VBAP also include a
- <dfn>spread</dfn> parameter, which will distribute the signal over a
- greater number of speakers in order to maintain constant (but no longer
- maximal) sharpness, regardless of position. Ardour's VBAP panner does not
+ <dfn>spread</dfn> parameter, which will distribute the signal over a
+ greater number of speakers in order to maintain constant (but no longer
+ maximal) sharpness, regardless of position. Ardour's VBAP panner does not
currently include this feature.
</p>
<h2>Speaker layout</h2>
+
+<figure class="right">
+ <img class="mini" src="/images/VBAP-panner-5.png" alt="The VBAP panner with 5 outputs">
+ <figcaption>
+ The VBAP panner with 5 outputs
+ </figcaption>
+</figure>
+
<p>
Each VBAP panner is specific to its <dfn>speaker layout</dfn>—the
panner has
implementation must therefore include the possibility to define this
layout.
</p>
-<img src="/images/VBAP-panner-5.png" class="small right" alt="The VBAP
-panner with 5 outputs"/>
+
<p>
Ardour currently uses a simplified approach: if a track or bus has more
- than two output channels (which implies stereo), it assumes that you
- have N speakers distributed in a regular N-gon. That means that for
- irregular layouts such as 5.1 or 7.1, the direction you dial in will
- differ a bit from the actual auditory result, but you can still achieve
- any desired spatialisation.
+ than two output channels (which implies stereo), it assumes that there are
+ N speakers distributed in a regular N-gon. That means that for
+ irregular layouts such as 5.1 or 7.1, the direction dialed in will
+ differ a bit from the actual auditory result, but any desired spatialisation
+ can still be achieved.
</p>
-<h3>Experimental 3D VBAP</h3>
-<img src="/images/VBAP-panner-10.png" class="small right" alt="The VBAP
-panner with 10 outputs, in experimental 3D mode"/>
+
+<h3 class="clear">Experimental 3D VBAP</h3>
+<figure class="right">
+ <img class="mini" src="/images/VBAP-panner-10.png" alt="The VBAP panner with 10 outputs, in experimental 3D mode">
+ <figcaption>
+ The VBAP panner with 10 outputs, in experimental 3D mode
+ </figcaption>
+</figure>
+
<p>
For tracks with 10 outputs, Ardour will currently assume a 3-dimensional
speaker layout corresponding to Auro-3D 10.1, which is a horizontal 5.1
"voice-of-god" speaker at the zenith.
</p>
-<h2>N:M panning</h2>
-<img src="/images/VBAP-panner-4in5.png" class="small right" alt="The VBAP
-panner in 4 in, 5 out mode"/>
+<h2 class="clear">N:M panning</h2>
+
+<figure class="right">
+ <img class="mini" src="/images/VBAP-panner-4in5.png" alt="The VBAP panner in 4 in, 5 out mode">
+ <figcaption>
+ The VBAP panner in 4 in, 5 out mode
+ </figcaption>
+</figure>
+
<p>
For tracks and busses with more than one input, Ardour will (for now) assume that
- you wish to distribute the inputs symmetrically along the latitude around
+ the inputs are distributed symmetrically along the latitude around
the panner direction. The width parameter controls the opening angle of
the distribution sector.
</p>
-
projects / ardour-manual / blobdiff