公开(公告)号：EP1277300A4

公开(公告)日：2004-08-11

申请号：EP01926526

申请日：2001-04-02

申请人： MACROVISION CORP

发明人： KNAUFT CHRISTOPHER L

IPC分类号： G06F12/14 ,  G06F1/00 ,  G06F21/00 ,  G06F21/24 ,  G09C1/00 ,  H04L9/32 ,  H04K1/00 ,  G06F11/30 ,  H04N7/167

CPC分类号： G06F21/10 ,  G06Q20/3829 ,  H04L9/3247 ,  H04L9/3263 ,  H04L2209/603

摘要： A system for providing rights controlled access to digital media comprises a provider data processor (102) and a user data processor (104) connected by a communications network. The user data processor provides access to a data object (106) in accordance with rules (116) associated with the data object by the server data processor. The user data processor includes a machine key device (118) and a user key device (120). The machine key device is preferably an installed component of the client data processor that provides encryption, decryption, and authentication functionality for the client data processor. The user key device is preferably a removable, portable device that connects to the client data processor and provides encryption, decryption, and authentication functionality for a user. The use of a data object is restricted to a particular user and a particular data processor through the use of multiple layers of encryption.

公开(公告)号：EP0856224A4

公开(公告)日：1998-11-25

申请号：EP96936734

申请日：1996-10-17

申请人： MACROVISION CORP

发明人： QUAN RONALD

IPC分类号： H04N5/91 ,  G11B20/10 ,  G11B27/031 ,  H04N5/782 ,  H04N5/913 ,  H04N7/08 ,  H04N7/087 ,  H04N7/088 ,  H04N7/169 ,  H04N7/171 ,  H04N9/79 ,  H04N7/167

CPC分类号： H04N7/1713 ,  H04N5/913 ,  H04N7/08 ,  H04N7/087 ,  H04N7/088 ,  H04N7/1693 ,  H04N2005/91314 ,  H04N2005/91371

摘要： In a known copy protection process for preventing recording of video signals, pseudo sync and AGC pulses (Fig. 2) are present on predetermined lines within the blanking intervals of the video signal so that any subsequent video tape recording of the video signal shows a picture of very low entertainment quality. This copy protection process is defeated first by determining the location of the video lines containing the copy protection using the color burst signal or chroma in the horizontal blanking interval to determine online detection (Fig. 4). Then some or all of the lines including copy protection signals are modified so as to render the overall video signal recordable. The modification is accomplished in a number of ways, including gain shifting portions of the video signal, level shifting portions of the video signal, bandwidth limiting certain portions of the video signal or replacing certain portions of the video signal with other video elements (Fig. 5).