Patent ID: 7295673
Filing Date: 2007-11-13
Classification: H04K,H04L,H04N

Abstract:
1. A method for producing a protected stream of compressed video content, said method comprising: receiving an input stream of compressed video content containing a sequence of frames; generating a frame encryption key and storing the encryption key in a key table; creating a set of encrypted frames by encrypting at least selected portions of selected frames of said sequence of frames using the frame encryption keys in accordance with a frame encryption function; generating frame decryption information necessary to decrypt said set of encrypted frames including an encryption key pointer identifying a decryption key to be used in the decryption of each encrypted frame; and assembling at least said set of encrypted frames, unencrypted frames of said sequence of frames, and said frame decryption information to produce the protected stream of compressed video content; wherein said frame decryption information is synchronized with said set of encrypted frames into a synchronized frame decryption stream.