Allow video download and secure downloaded video to restrict video access after validity expires

I am workng on a project where I want the user to download the video 开发者_JAVA技巧but restrict access in a way that the video stops working if it is copied to any other machine. Also the video stops working after a certain period of time.

Can some stackoverflow gurus help me point in a right direction?

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To make a video file stop working, you need to have it encrypted or otherwise incompatible with well known formats and encodings. This assumes that the file is downloaded and/or streamed being encrypted, you have custom offline and/or streaming player which supports this type of encoding and your player is responsible for checking copies and expiry time.