I'm offering this up as free advice from someone (myself) who has been around a very long time.
I have in the past created content delivery applications that make stealing your content very difficult. It involves using a modified video codex that is not available to the public, the one i use is a modified version of a popular video format. Now this does not prevent them from recording you video from a browser, but that is a pain in the butt to do, they would have to want it bad. If they were able to download the video from you they would not be able to play it.
I'm not going to let my secretes completely out of the bag, but if you can read between the lines you can I am sure figure this out for yourselves.
The other option is to NOT use an standard player but custom player that has access to running processes on the host machine that can detect ripping applications. MMO games use this method to stop cheaters. It is not easy to do, but it can be done.
Anyway that's my
Feel free to contact me if you have questions.