Mention that ffmpeg-harvid is used for mp3 support

[ardour-manual] / include / export-format-profiles.html

<h2>Export Format Profiles</h2>

<p>
  An Export Format Profile specifies the file format in which Ardour will export
  audio files, and also other audio file export options.
</p>

<p>
  Export Format Profiles are edited via the <kbd class="menu">Edit Export Format
  Profile</kbd> dialog.
</p>

<figure class="right">
  <img src="/images/edit-export-format-profile.png" alt="The 'Edit Export Format Profile' dialog">
  <figcaption>
    The 'Edit Export Format Profile' dialog
  </figcaption>
</figure>

<h3>Normalize</h3>
<p>
  If enabled, levels of exported files will be normalized to the level chosen here.
  The normalization can be either:
</p>

<ul>
  <li>Peak, which adjusts the gain to bring the highest signal peak to the
    chosen level (in <acronym title="decibels relative to full scale">dBFS</acronym>),</li>
  <li>Loudness, which adjusts the gain to bring the average amplitude to the
    chosen level (in <acronym title="loudness units relative to full scale">LUFS</acronym>),
    without exceeding the chosen true-peak value (in
    <acronym title="decibels true peak">dBTP</acronym>).
    EBU R128 is only available for mono or stereo sounds while true-peak works
    for any channel layout.</li>
</ul>

<h3>Trim silence at start/end</h3>
<p>
  These checkboxes allow to remove any part Ardour considers silent (0dB),
  at the beginning or/and end of each exported track.
</p>

<h3>Add silence at start/end</h3>
<p>
  These checkboxes allow to add silence at the beginning or/and end of each
  exported track. The duration of the added silence can be manually fixed in the
  adjacent 'timer' input fields.

<h3>Compatibility/Quality/File format/Sample rate</h3>

<h4>Compatibility</h4>
<p>
  Selecting an item in the 'Compatibility' emphasizes the settings in the other
  columns that are compatible with the selected standard, by turning incompatible
  options red. When an incompatible quality/format/sample rate is selected, the
  compatibility column checkbox disappears.
</p>

<h4>Quality</h4>
<p>
  The appropriate item in the 'Quality' column will be highlighted when a file format
  is chosen. At the moment, selecting a Quality setting does not show the
  compatible File formats.
</p>

<h4>File format</h4>
<p>
  This column contains a list of Ardour's supported export file types. Selecting
  one updates the options underneath it.
</p>
<p>
        Note: For mp3 export ardour relies on ffmpeg to encode the file. This comes bundled
        with the video-tools (and is always available when you install the official Ardour
        binary.
</p>

<h4>Sample rate</h4>
<p>
  A specific sample rate can be chosen for the exported files, or the current session's
  sample rate (by choosing 'Session rate'), without sample rate conversion.
</p>

<h4>Sample rate conversion quality</h4>
<p>
  In case the chosen sample rate does not match the current session's sample rate,
  the sample rate conversion quality can be chosen here. Better quality options are
  slower.
</p>

<h3>Format Options</h3>
<p>
  Options relevant to the chosen file format will appear just under the
  Compatibility/Quality/File format/Sample rate table.
</p>

<h4>Tag with session's metadata</h4>
<p>
  If the exported file format supports metadata (e.g. FLAC, Ogg Vorbis), use data
  entered in the <a href="@@metadata">Session Metadata</a> window to tag the
  exported files.
</p>

<h4>Sample Format and Dithering</h4>
<p>
  The <kbd class="menu">Sample Format</kbd> is the bit depth of exported files,
  i.e. the numbers of values a sample can have. Increasing the sample format
  results in a better defined audio file at the cost of increasing the file size.
</p>
<p>
  If the exported files bit depth is less than Ardour's native bit depth
  (32 bits floating point by default), the dithering algorithm, that chooses how
  to compute the conversion can be chosen in the <kbd class="menu">Dithering</kbd>
  column.
</p>

<h3>Options</h3>
<p>
  These options are presented whatever the chosen format is:
</p>

<h4>Create CUE/TOC/chapter mark file</h4>
<p>
  As well as exporting an audio file, Ardour can create a file (in CUE, TOC or MP4ch format
  respectively) containing CD track information, as defined in the
  <a href="@@the-ranges-and-marks-lists">Ranges &amp; Marks List</a>.
  Those files can then be used to either burn a CD or DVD, or to create "chapters"
  inside a compatible mp4 video container.

<h3>Label</h3>
<p>
  The <kbd class="menu">Label</kbd> field allows to choose the name which will be
  shown for this format in the drop-down list of export formats in the
  'File Formats' tab of the <a href="@@export-dialog">Export dialog</a>.
</p>

<h3>Command to run post-export</h3>
<p>
  If this is not blank, it is considered as a command to be run after the export
  of each file. Either the command must exist in $PATH, or an absolute path to
  an executable file can be specified here.
</p>

<p>
  Certain sequences are allowed here to stand for the exported file name and
  various parameters. Currently these are:
<table class="dl">
<tr><th><code>%f</code></th>
<td>Full path and filename of the exported audio file</td></tr>
<tr><th><code>%d</code></th>
<td>Directory containing the exported audio file (including trailing directory separator)</td></tr>
<tr><th><code>%b</code></th>
<td>Basename of the exported audio file (without extension)</td></tr>
<tr><th><code>%s</code></th>
<td>Path to the current session file</td></tr>
<tr><th><code>%n</code></th>
<td>Name of the current session file</td></tr>
<tr><th><code>%%</code></th>
<td>A literal percent sign</td></tr>
</table>

<p>
  Any part of the command-line enclosed in double-quotes (") will be used as-is.
</p>

<p>
  For example, exporting an mp3 file can be done by inserting <code>lame -b320 %f</code>
  which will convert the exported audio file ('%f') to a 320 kbs mp3 using the lame encoder
  (provided lame is installed first on the system).
</p>