I want to have a full screen video Landing Page

[Moved from Your WordPress which is NOT a support forum.]

Hi,
We want to set a Full Screen video landing page for our company website.(Something similar to this company’s site:http://www.astutepayroll.com/)

The theme we are using is: Increase and we are quite comfortable with it.

I am using a plugin “LambertGroup – Full Screen Background and Full Width Slider”. It only allows us to use a YouTube video.But once the video upload to youtube, the quality will be largely impact.
We have a high quality video saved in the local drive we would like to upload. But we don’t know how to do it. Is there any other way or plugin to do it without changing the current theme?

Please HELP!!! We would like to make this website go live next week.

MANY THANKS!