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<h4>This Page</h4>
<ul class="toc">
<li><a href="#accessing-videos">Accessing videos</a></li>
<li><a href="#accessing-metadata">Accessing metadata</a></li>
<li><a href="#generating-thumbnails">Generating thumbnails</a></li>
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<h1>Video Operations</h1>
<ul class=page-meta>
<li>New in Lektor Version <em>3.2</em></li>
</ul>
<p>Just like <a href="../imageops/">images</a>, videos are separate files that are embedded into HTML files. Since they are media files, it's often desirable to read metadata or manipulate them in some way.</p>
<div class="admonition admonition-info"><p>Video metadata access is powered by <a href="https://ffmpeg.org/">FFmpeg</a>. In order to use it FFmpeg must be installed on your system and detected by Lektor. If Lektor is unable to find FFmpeg you will see the error message <code>Unable to locate ffmpeg or ffprobe executable. Is it installed?</code> in your console output if you try to use functionality that requires it.</p></div><h2 id="accessing-videos">Accessing videos</h2><div class="hll"><pre><span></span><span class="cp">{%</span> <span class="k">for</span> <span class="nv">video</span> <span class="k">in</span> <span class="nv">this.attachments.videos</span> <span class="cp">%}</span>
<span class="p">&lt;</span><span class="nt">div</span> <span class="na">class</span><span class="o">=</span><span class="s">&quot;video&quot;</span><span class="p">&gt;&lt;</span><span class="nt">video</span> <span class="na">src</span><span class="o">=</span><span class="s">&quot;</span><span class="cp">{{</span> <span class="nv">video</span><span class="o">|</span><span class="nf">url</span> <span class="cp">}}</span><span class="s">&quot;</span><span class="p">&gt;&lt;/</span><span class="nt">div</span><span class="p">&gt;</span>
<span class="cp">{%</span> <span class="k">endfor</span> <span class="cp">%}</span>
</pre></div>
<p>Just like images you can also access them using <code>site.get('/myfolder').attachments.videos</code> or <code>site.get('/myfolder').attachments.get('examplevideo.mp4')</code>. Note that not all formats are detected as videos (see <a href="../../content/attachments/">attachments</a>). If your format is not in the list you may still be able to get it detected as a video by adding it to your <a href="../../project/file/#attachment-types">Lektor project file</a>.</p>
<h2 id="accessing-metadata">Accessing metadata</h2><p>Video objects are sub-classes of Attachments but with a few extra properties.</p>
<table>
<thead><tr>
<th>Attribute</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>width</code></td>
<td>Video height in pixels</td>
</tr>
<tr>
<td><code>height</code></td>
<td>Video height in pixels</td>
</tr>
<tr>
<td><code>duration</code></td>
<td>Video length as a <a href="https://docs.python.org/3/library/datetime.html"><code>datetime.timedelta</code></a> instance</td>
</tr>
</tbody>
</table>
<p>Example:</p>
<div class="hll"><pre><span></span><span class="cp">{%</span> <span class="k">set</span> <span class="nv">video</span> <span class="o">=</span> <span class="nv">this.attachments.videos.first</span><span class="o">()</span> <span class="cp">%}</span>
<span class="p">&lt;</span><span class="nt">video</span> <span class="na">src</span><span class="o">=</span><span class="s">&quot;</span><span class="cp">{{</span> <span class="nv">video</span><span class="o">|</span><span class="nf">url</span> <span class="cp">}}</span><span class="s">&quot;</span><span class="p">&gt;</span>
<span class="p">&lt;</span><span class="nt">dl</span><span class="p">&gt;</span>
<span class="p">&lt;</span><span class="nt">dt</span><span class="p">&gt;</span>Width:<span class="p">&lt;/</span><span class="nt">dt</span><span class="p">&gt;</span>
<span class="p">&lt;</span><span class="nt">dd</span><span class="p">&gt;</span><span class="cp">{{</span> <span class="nv">video.width</span> <span class="cp">}}</span> px<span class="p">&lt;/</span><span class="nt">dd</span><span class="p">&gt;</span>
<span class="p">&lt;</span><span class="nt">dt</span><span class="p">&gt;</span>Height:<span class="p">&lt;/</span><span class="nt">dt</span><span class="p">&gt;</span>
<span class="p">&lt;</span><span class="nt">dd</span><span class="p">&gt;</span><span class="cp">{{</span> <span class="nv">video.height</span> <span class="cp">}}</span> px<span class="p">&lt;/</span><span class="nt">dd</span><span class="p">&gt;</span>
<span class="p">&lt;</span><span class="nt">dt</span><span class="p">&gt;</span>Duration:<span class="p">&lt;/</span><span class="nt">dt</span><span class="p">&gt;</span>
<span class="p">&lt;</span><span class="nt">dd</span><span class="p">&gt;</span><span class="cp">{{</span> <span class="nv">video.duration.total_seconds</span><span class="o">()</span> <span class="cp">}}</span> s<span class="p">&lt;/</span><span class="nt">dd</span><span class="p">&gt;</span>
<span class="p">&lt;/</span><span class="nt">dl</span><span class="p">&gt;</span>
</pre></div>
<h2 id="generating-thumbnails">Generating thumbnails</h2><p>The main difference between video and image attachments is how thumbnails are handled. Since a video basically is a long sequence of images you must first choose where in the video the thumbnail should be generated. This is done using the `.frame() method. There are multiple ways of calling it:</p>
<table>
<thead><tr>
<th>Method</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>frame()</code></td>
<td>Use a frame from the middle of the video <em>(default)</em></td>
</tr>
<tr>
<td><code>frame(seek: float)</code></td>
<td>Fraction between 0.0 and 1.0 of the video duration from where to extract the frame. The value <code>0.5</code> means that the middle of the video will be used. It can be seen as a shorthand for <code>video.frame(video.duration * seek)</code>.</td>
</tr>
<tr>
<td><code>frame(seek: datetime.timedelta)</code></td>
<td>Use a frame at the given seek distance from the beginning of the video. This is useful when you want to seek a fix time into a video.</td>
</tr>
</tbody>
</table>
<p>Calling this method will return a <code>VideoFrame</code> instance, which is not usable by itself. It does however just like an image have a thumbnail method.</p>
<p>Example:</p>
<div class="hll"><pre><span></span><span class="cp">{%</span> <span class="k">set</span> <span class="nv">video</span> <span class="o">=</span> <span class="nv">this.attachments.videos.first</span><span class="o">()</span> <span class="cp">%}</span>
<span class="p">&lt;</span><span class="nt">img</span> <span class="na">src</span><span class="o">=</span><span class="s">&quot;</span><span class="cp">{{</span> <span class="nv">video.frame</span><span class="o">()</span><span class="nv">.thumbnail</span><span class="o">(</span><span class="m">300</span><span class="o">,</span> <span class="m">200</span><span class="o">,</span> <span class="nv">mode</span><span class="o">=</span><span class="s2">&quot;crop&quot;</span><span class="o">)|</span><span class="nf">url</span> <span class="cp">}}</span><span class="s">&quot;</span><span class="p">&gt;</span>
<span class="p">&lt;</span><span class="nt">img</span> <span class="na">src</span><span class="o">=</span><span class="s">&quot;</span><span class="cp">{{</span> <span class="nv">video.frame</span><span class="o">(</span><span class="m">0.1</span><span class="o">)</span><span class="nv">.thumbnail</span><span class="o">(</span><span class="m">300</span><span class="o">,</span> <span class="m">200</span><span class="o">,</span> <span class="nv">mode</span><span class="o">=</span><span class="s2">&quot;crop&quot;</span><span class="o">)|</span><span class="nf">url</span> <span class="cp">}}</span><span class="s">&quot;</span><span class="p">&gt;</span>
</pre></div>
<p>Note that unlike images it is not possible to get an URL to a video frame directly:</p>
<div class="hll"><pre><span></span><span class="cp">{%</span> <span class="k">set</span> <span class="nv">video</span> <span class="o">=</span> <span class="nv">this.attachments.videos.first</span><span class="o">()</span> <span class="cp">%}</span>
<span class="p">&lt;</span><span class="nt">img</span> <span class="na">src</span><span class="o">=</span><span class="s">&quot;</span><span class="cp">{{</span> <span class="nv">video.frame</span><span class="o">()|</span><span class="nf">url</span> <span class="cp">}}</span><span class="s">&quot;</span><span class="p">&gt;</span> <span class="cm">&lt;!-- This is not valid --&gt;</span>
</pre></div>
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