Abstract: Electronic steganographic techniques can be used to encode a rights management control signal onto an information signal carried over an insecure communications channel. Steganographic techniques ensure that the digital control information is substantially invisibly and substantially indelibly carried by the information signal. These techniques can provide end-to-end rights management protection of an information signal irrespective of transformations between analog and digital. An electronic appliance can recover the control information and use it for electronic rights management to provide compatibility with a Virtual Distribution Environment. In one example, the system encodes low data rate pointers within high bandwidth time periods of the content signal to improve overall control information read/seek times.

Abstract: A VGA (or other component video signal) output, e.g. from a computer or DVD player, is subject to protection so it is viewable on a VGA monitor. If the component video signal is converted to composite video (e.g. television) the resulting television picture is of substantially degraded quality, thereby inhibiting viewing and/or copying. This protects for instance copyrighted material in the VGA format from unauthorized use. The protection modifies the horizontal or vertical synchronization signals in the VGA video in such a way that there is no adverse affect on a typical VGA monitor. Most or all VGA to television converters and/or television sets and VCR's suffer from loss of synchronization, resulting in an unviewable picture. Methods and apparatuses for defeating this copy protection are provided herein.

Abstract: A television transmission security system, including scrambling a television signal by suppressing at least one of the horizontal sync pulse and vertical blanking interval of the television signal; transmitting the scrambled television signal; generating, and separately transmitting along with the scrambled television signal, a pilot carrier that includes timing information corresponding to the horizontal sync pulse and/or vertical blanking interval; and descrambling the scrambled television signal including receiving the pilot carrier and periodically suppressing, in accordance with the timing information included in the pilot carrier, video information of the television signal to an extent whereby at least one of the horizontal sync pulse and vertical blanking interval becomes detectable by a television receiver, thereby initiating organized receipt and display of the television signal.

Abstract: Electronic steganographic techniques can be used to encode a rights management control signal onto an information signal carried over an insecure communications channel. Steganographic techniques ensure that the digital control information is substantially invisibly and substantially indelibly carried by the information signal. These techniques can provide end-to-end rights management protection of an information signal irrespective of transformations between analog and digital. An electronic appliance can recover the control information and use it for electronic rights management to provide compatibility with a Virtual Distribution Environment. In one example, the system encodes low data rate pointers within high bandwidth time periods of the content signal to improve overall control information read/seek times.

Abstract: A novel method and apparatus for scrambling a television signal includes using a synchronization separator to separate a synchronization signal from an input audio-visual signal. The synchronization signal is then used to regulate an oscillator producing an audio carrier signal. In this manner, the audio-visual signal is transmitted without the component synchronization signal rendering it useless to a conventional television receiver. The descrambler and descrambling method of the invention involve removing the audio carrier signal from the scrambled signal and using the audio carrier signal to generate the color sub-carrier signal and a vertical time frame reference signal necessary to synchronize the transmitted audio visual signal for display.

Abstract: A multichannel television access control system is disclosed wherein processing of the broadband signal is performed by gated coherent RF injection on a plurality of channels, thereby effecting selective descrambling of an arbitrary subset of channels in a channel group. The system provides for a closed loop injection signal phasor control so as to maintain substantially constant relationship between the television signals and the injected signals. The combined signals are supplied to subscribers enabling the use of their cable ready equipment.

Abstract: A multichannel television access control system is disclosed wherein processing of the broadband signal is performed by gated coherent RF injection on a plurality of channels, thereby effecting selective descrambling of an arbitrary subset of channels in a channel group. The system provides for a closed loop injection signal phasor control so as to maintain substantially constant relationship between the television signals and the injected signals. The combined signals are supplied to subscribers enabling the use of their cable ready equipment.

Abstract: The apparatus comprises: a first module including a universal key; a second module including a unique identifier and a unique key wherein the unique key is derived from the unique identifier and the universal key and incorporated into the second module during manufacture of the second module. The second module is in communication with the first module. The apparatus further comprises a controller for performing the following subsequent to manufacture of the first module and the second module: initiating a communication session between the first module and the second module; transmitting the unique identifier from the second module to the first module; and deriving the unique key in the first module using the unique identifier and the universal key. A method for synchronization of cryptographic keys between modules of a distributed system and a method of manufacturing a postage evidencing system are also provided.

Abstract: A method and apparatus is disclosed for disabling the effect of copy protection signals embedded in video signals, wherein the detection and modification of the copy protection signals is accomplished in the RF domain rather than in the baseband video domain as typically accomplished at the present time. To this end, various embodiments are disclosed for deriving a timing control signal from the modulated RF carrier signal, which timing control signal is indicative of the television lines which contain the copy protection signals. Several techniques in the RF domain responsive to the timing control signal are disclosed for replacing, attenuating, suppressing, pulse narrowing or otherwise modifying the modulated RF carrier signal during the interval of the copy protection signals to disable the affects thereof, to allow the making of acceptable recordings during demodulation subsequently by, for example, a record VCR.

Abstract: A scrambling system for a cable television system in which a group of channel frequencies are reused over a plurality of service areas includes an access controller, an encoder and a plurality of simplified scrambling units. Each service area receives different television signals on the group of channel frequencies. The access controller provides signal authorization information for a given channel frequency to a plurality of receiver/decoders located in the different services areas. The access controller also provides descrambling information corresponding to the signal authorization information to the encoder for the given channel frequency. The encoder produces a conditional access code by placing the descrambling information into a scrambled reference signal. An extracting unit removes the conditional access code from the scrambled reference signal and distributes the conditional access code to each of the simplified scrambling units operating at the given channel frequency.

Abstract: A method for defeating illegal receivers sensitive to the edges of synchronization signals in a scrambled video signal is provided. The scrambled video signal includes synchronization signals having levels which prevent a standard receiver from detecting the synchronization signals by using the levels of the synchronization signals. The synchronization signals also have one or more pulses with level transitions above or below a signal detection threshold level of the standard television receiver which prevent the illegal receivers from detecting the synchronization signals by using the edges of the synchronization signals.