Also against theft helps:
1. complicate the theft process. for example, the issuance of temporary links, the separation of physical files and the issuance of them entirely only in the player. But of course this will not protect against targeted theft, but it can limit its number, because not all will can do it.
2. the economy works - complaints work best, in the system of payment acceptance. Accepting payments for stolen content is complicated.
3. complaints in Google and hosting to remove links or themselves stolen files.
All together gives a good effect, but at the moment there is no 100% protection against theft of digital content. There were attempts to introduce DRM, a rights management system, but they did not get accustomed to the video. But in games they took root.
The best protection is the constant need for the client to go for updates to your server and deliver content in small portions, as in social networks.
Then it will be more convenient for people to follow you, and not to collect stolen content on the Internet in pieces.
