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Data URI for Preview Thumbnails with HLS streaming (JWPlayer 6.11)


I'm using JWPlayer 6.11, and trying to display preview thumbnails on the player with both progressive playback (by loading a plain MP4 video) and HLS playback (by using an m3u8 file).
Also, I need to build the contents of the preview thumbnails' VTT file dynamically on the browser side, so I'm using Data URIs. (e.g. "data:text/vtt;...").

Every scenario except the HLS + Data URI VTT is working:
- play an MP4 file, using static VTT file: works ok.
- play an MP4 file, using a DATA URI VTT: works ok.
- HLS streaming, using static VTT file: works ok.
- HLS streaming, using DATA URI VTT: NOT WORKING.

I'm not getting any console error nor js error. No feedback at all from the player.

What can I do to get this working?
I really need HLS streaming and use a data URI VTT.

Here's a test page:

I don't have a license for JWPlayer 7, so I can't know if this is fixed in 7.x.


1 Community Answers


JW Player Support Agent  
0 rated :

Hi, Guille.

My name is Alex and I am one of the Support Engineers at JW Player. I will be more than happy to assist you with your questions.

Because the content is streaming, there is no way to dynamically generate thumbnails on-the-fly. The player is only receiving a few seconds of the stream in advance. What you are doing would only work with a progressive file, such as the MP4 that you are seeing it work with.

Please let me know if you need any more help or have any other questions.

Thank you!

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