o;</dt>
<dd><p>Set the grabbing frame rate. Default value is <code>ntsc</code>,
corresponding to a frame rate of <code>30000/1001</code>.
</p>
</dd>
</dl>

<a name="x11grab"></a>
<h2 class="section"><a href="ffmpeg-devices.html#toc-x11grab">3.22 x11grab</a></h2>

<p>X11 video input device.
</p>
<p>To enable this input device during configuration you need libxcb
installed on your system. It will be automatically detected during
configuration.
</p>
<p>This device allows one to capture a region of an X11 displ