manual/include/strip-silence-from-audio-regions.html

<figure>
  <img src="/images/strip-silence-window.png" alt="The Strip Silence window">
  <figcaption>
    The Strip Silence window
  </figcaption>
</figure>

<p>
  The <dfn>Strip Silence</dfn> tool allows to remove the parts of one or multiple
  regions that are below a user-defined silence threshold. It does <em>not</em>
  destroy the underlying audio, but trims the regions according to the silence
  threshold parameter. The edit applies to all selected regions, allowing batch
  processing.
</p>

<p>
  The window, accessible either through the <kbd class="menu">Region &gt; Edit &gt; Strip
  Silence</kbd> menu or <kbd class="menu"><kbd class="mouse">right</kbd> click on a region
  &gt; <em>Name_Of_The_Region</em> &gt; Edit &gt; Strip Silence</kbd>is made of:
</p>

<table class="dl">
  <tr><th><dfn>Threshold</dfn></th>
    <td>The audio level under which the audio is considered silent (in <abbr
    title="Decibels relative to Full Scale">dBFS</abbr>)</td></tr>
  <tr><th><dfn>Minimum length</dfn></th>
    <td>A minimum number of samples for Ardour to create a split. Under this
      number, the region won't be sliced</td></tr>
  <tr><th><dfn>Fade length</dfn></th>
    <td>Ardour adds fades, both in and out, to the trimmed regions, to the created
      region (so the sliced regions are longer by both the in and out fades duration,
      expressed in samples)</td></tr>
  <tr><th>A progress bar</th>
    <td>showing the time Ardour takes to compute the trimming based on the current
      parameters</td></tr>
</table>

<p>
  Changing any parameter in the window is reflected in the main editor: the silent
  segments are highlighted and the number and durations of the shortest segments is
  displayed, helping fine-tune the parameters.
</p>

<figure>
  <img src="/images/strip-silence-audio.png" alt="strip silence: view of the audio">
  <img src="/images/strip-silence-after.png" alt="strip silence: view of the audio after">
  <figcaption>
    Strip Silence : a view of the audio while changing the parameters, and after treatment
  </figcaption>
</figure>

<p class="note">The minimum length for silence can be useful when editing very
  percussive material and just needing to automatically trim the ends of a region.
</p>