Lightweight video stream data encryption method, system and device based on password card

The invention provides a lightweight video stream data encryption method, system and device based on a cipher card. According to the method, the reference video stream needing to be encrypted is segmented to obtain the N video segments, the N Gray codes in one-to-one correspondence with the video segments are generated, the N video segments are reordered according to the size sequence of the N Gray codes, each video segment is encrypted through the corresponding first secret key to obtain the encrypted video stream, and the encryption efficiency is improved. The consumption of computing resources is reduced, and the response speed is increased; different secret keys are adopted to encrypt different video segments, so that the security of encryption of the lightweight video stream data based on the password card is improved; the Gray code sequence and the first secret key are further encrypted to obtain the secret key file, and the encrypted video stream and the secret key file are sent to the decryption end d