manual/_manual/26_video-timeline/03_operations.html

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---
layout: default
title: Workflow & Operations
---
<h2>Overview of Operations</h2>
<dl class="wide-table">
<dt><kbd class="menu">Session &gt; Open Video</kbd></dt>
<dd>Add/replace a video to/on the timeline</dd>
<dt><kbd class="menu">Window &gt; View Monitor</kbd></dt>
<dd>Open/close external video monitor window</dd>
<dt><kbd class="menu">View &gt; Video Monitor &gt;</kbd></dt>
<dd>Various settings of the video monitor</dd>
<dt><kbd class="menu">Session &gt; Export &gt; Video</kbd></dt>
<dd>Export session and multiplex with video-file</dd>
<dt><kbd class="mouse">Left</kbd>-drag the video in the timeline</dt>
<dd>Re-align video and move 'locked' audio-regions along</dd>
<dt>Context-menu on the video-timeline: <kbd class="menu"> &#039;lock&#039;</kbd></dt>
<dd>Prevent accidental drags</dd>
<dt>Audio region context menu: <kbd class="menu">Position &gt; Lock to video</kbd></dt>
<dd>Mark audio region(s) to be moved along with the video.</dd>
</dl>
<h2>Adding Video</h2>
<p>
Adding video is a two-step process: select a video file, and choose
import mode and optionally select an audio track to extract.
</p>
<p>
The first step is rather straight-forward. The panel on the right side
allows to seek through the video and displays basic file information.
It is also useful to check if the video format/codec is supported:
</p>
<img src="/images/a3_video_open.png" alt="video-open-dialog" width="300" />
<p>
The second step analyzes the video file in more detail and offers import options:
</p>
<dl>
<dt><kbd class="menu">Import/Transcode to Session</kbd></dt>
<dd>This is the default. The video will be imported in a suitable
video format/codec for the timeline and video monitor and saved inside the
session folder. A location other than the session folder can also be
chosen (external disk, or network storage of the video server on a different
machine).</dd>
<dt><kbd class="menu">Reference from Current Location</kbd></dt>
<dd>Only useful for opening files that were previously encoded (are already
in a good format/codec). Use with care.</dd>
<dt><kbd class="menu">Do not Import Video</kbd></dt>
<dd>Useful for extracting audio only.</dd>
</dl>
<img src="/images/a3_video_import.png" alt="Video Import Dialog" width="300" />
<p>
By default the video is imported using the original width/height.
If it is a large video (e.g. full-HD) it makes sense to scale it down
to decrease the CPU load and disk I/O required to decode and play the
file.<br />
A small, low-quality representation of the image is usually sufficient
for editing soundtracks. The default bitrate in kbit/sec is set to use
0.7 bits per pixel. (Compare: the average DVD medium uses 5000&nbsp;kbit/s;
at PAL resolution this is about 0.5 bits per pixel. But the DVD is
using the <dfn>mpeg2</dfn> &mdash; a denser compression algorithm than the
<dfn>mjpeg</dfn> codec used by Ardour.)
</p>
<h2>Working with A/V</h2>
<p>
Well now,..
</p>
<img src="/images/a3_videotimeline.png" alt="Video Timeline" width="600" />
<h2 id="export">Exporting Video</h2>
<p>
The video export will take audio from the current Ardour session and
multiplex it with a video file. The soundtrack of the video is taken from
an audio export of Ardour's master bus.
</p>
<p>
An arbitrary video file can be chosen. For high quality exports, the
original file (before it was imported into the timeline) should be used.
This is the default behaviour if that file can be found. If not, Ardour
will fall back to the imported proxy-video which is currently in use
on the timeline. Any existing audio tracks on this video file are stripped.
</p>
<p>
The range selection allows to cut or extend the video. If the session is
longer than the video duration, black frames are prefixed or appended to
the video. (Note: this process may fail with non-standard pixel aspect
ratios). If Ardour's session range is shorter, the video will be cut accordingly.
</p>
<p>
Audio samplerate and normalization are options for Ardour's audio exporter.
The remaining settings are options that are directly passed on to ffmpeg.
</p>
<p>
The file format is determined by the extension that you choose for it
(.avi, .mov, .flv, .ogv, .webm,...)
Note: not all combinations of format, codec, and settings produce files
which are according to specifications. For example, flv files require
sample rates of 22.1&nbsp;kHz or 44.1&nbsp;kHz, mpeg containers can not
be used with ac3 audio-codec, etc. If in doubt, use one of the built-in
presets.
</p>
<img src="/images/a3_video_export.png" alt="Video Export Dialog" width="300" />
<p>
Ardour video export is not recommended for mastering! While ffmpeg
(which is used by Ardour) can produce high-quality files, this export
lacks the possibility to tweak many settings. We recommend to use winff,
devede or dvdauthor to mux &amp; master. Nevertheless this video-export c
omes in handy to do quick snapshots, intermediates, dailies or online videos.
</p>