A while ago I did this for webtop (Video streaming from Webtop) which was later published by EMC as a white paper. This is a similar attempt using an external widget on D2.

In this case, I’ve used video.js, a free Javascript video player. The widget itself is quite straightforward, just create a normal external widget, register the D2_EVENT_SELECT_OBJECT and configure the external widget sending via parameter the user name, the repository and the session ticket. Once this is done, you just have to get the r_object_id of the selected document, set that value on the video object via JS, and just enjoy.

You can check the full on code on GitHub.