Web Presenter Video Encoding & Programming

We need to set up an online web presenter like the ones found in the following pages: [login to view URL] [login to view URL] Video of the presenter has already been shot, and video file contains alpha information for overlay transparency. We need this video to be cut, encoded and programmed into a website so it overlays just like the examples in the websites cited above. Alpha channel (background) must be transparent so presenter is shown "above" the website, not inside a rectangle with white background. Video player also must show controls (play, pause, rewind, forward, volume control). Would prefer an HTML5 solution if possible. Flash only if no other method/option is available. Video file would be made available via WeTransfer, and project would have to be completed. Video runs for 6 minutes and would have to be cut into 5-10 segments.