e LSB in the mask. Selected lines
which do not contain teletext information will be ignored. You can use the
special &lsquo;<samp>all</samp>&rsquo; constant to select all possible lines, or
&lsquo;<samp>standard</samp>&rsquo; to skip lines 6, 318 and 319, which are not compatible with
all receivers.
</p>
<p>For SD sources, ffmpeg needs to be compiled with <code>--enable-libzvbi</code>. For
HD sources, on older (pre-4K) DeckLink card models you have to capture in 10
bit mode.
</p>
</dd>
<dt>&lsquo;<samp>chan