I downloaded a subtitle from subscene http://subscene.com/subtitles/the-5th-wave/english/1298314 and it contains some coding such as :&lt;i&gt; and &lt;/i&gt; which is not being decoded by my player mpv . As can be seen the subtitle is in .srt (Subrip Text) format. https://matroska.org/technical/specs/subtitles/srt.html Here's a full dialog so that it may make sense. 2800:03:37,080 --> 00:03:39,280CASSIE:&lt;i&gt; I miss the Cassie I was.&lt;/i&gt;I want to fix this so that the codes are not visible during play but don't know how. Can somebody help. I am on Debian testing and using mpv [$] mpv --version                                                                                                               (null) requires an argumentmpv 0.14.0 (C) 2000-2015 mpv/MPlayer/mplayer2 projects built on UNKNOWNffmpeg library versions:   libavutil       54.31.100   libavcodec      56.60.100   libavformat     56.40.101   libswscale      3.1.101   libavfilter     5.40.101   libswresample   1.2.101ffmpeg version: 2.8.6-1+b2Look forward to how this can be fixed. Those codes are throughout the whole .srt file so its a bit disconcerting at best. 
What does :<i> code stand for in subtitles?
text processing
Looks like someone tried to use HTML tags for the subtitles and tried to make the fonts italic. In my limited HTML knowledge, &lt; stands for less than sign, i.e. < and &gt; stands for >. So CASSIE:&lt;i&gt; I miss the Cassie I was.&lt;/i&gt;can be visualized as CASSIE:<i> I miss the Cassie I was.</i>as you can easily see this is Italic code and the video player doesn't understand html tags. I am pretty sure they can be removed by few select sed/awk combinations, something likesed 's/\&lt\;i\&gt\;//; s+\&lt\;/i\&gt\;++' somefile.srt >somefile-nohtml.srt