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Is documented at https://wiki.dlib.indiana.edu/display/VarVideo/Matterhorn+Engage+Player
Strobe Media Playback
http://www.osmf.com/downloads/pdf/Strobe_Media_Playback_Presentation.pdf
There is a fallback from Flash to HTML5, but does not have an option to specify source (RTMP or mp4) for each type of player.
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