You can't cast the screen on demand in advance. Because VOD plays are encrypted by DRM digital rights management technology, some functions such as screen projection, caching, screen capture and screen recording will be restricted, which is one of the important means to protect genuine content from infringement. Generally speaking, dramas on demand in advance can only be watched on mobile phones.

Digital Rights Management (drm) is a similar authorization and authentication technology, which can prevent the illegal use of video content. DRM mainly adopts data encryption, copyright protection, digital watermarking and signature technology. Data encryption: it uses a certain digital model to reprocess the original information, and the user must provide the password.

Copyright protection: First, the terms and place codes that the content of the work can be legally used are embedded in the text, and the work is only allowed to be used if the conditions are met. Digital watermarking: embedding specific information representing the identity of copyright owner, publisher's information and terms of use into data. Even if the data is damaged, the watermark is valid as long as the damage is not serious. You can mark the copyright with water to prevent users from illegally spreading it.