I found a solution which involves encoding the subtitles into the video ahead of time.<br><br>
VLC can read SubRip file format and many others. https://en.wikipedia.org/wiki/SubRip. SubRip files are plain text and easy to create but for OpenLP the subtitles needed to be encoded in the video file whichever player you are choosing.
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Lots of sources claim VLC can encode the subtitles in for you. I couldn’t get that to work on OSX or Windows. Instead I used HandBrake from https://handbrake.fr/<br><br>
Create subtitles file
Create subtitle text file in the same folder as the video with identical name to video and .srt suffix
Subtitle format described in wikipedia page above.
Check subtitles with VLC (directly not via OpenLP) it will find subtitles file automatically
With HandBrake encode the subtitles into the video file
Select source video file
On subtitles tab select subtitles file
Select burned in and unselect other subtitle options.
There are no controls for font size or colour.
Select destination
Hit start
Result a subtitled video ready to presentation.<br><br>If anyone finds a solution which allows the style of the subtitle to be controlled when embedding I would be grateful to here about it.<br><br>Simon