Video scrambling system

Apparatus for use in creating an output signal from at least three input signals that are each divided into predetermined portions, the apparatus comprising:

• means for generating a pseudo-random number sequence said pseudo-random number sequence being generated in response to a set of controlling parameters;
• means responsive to said pseudo-random number sequence for combining portions from each of said at least three signals to create said output signal;
• means for receiving requests for said set of controlling parameters from at least one remote location at which means for reconstructing at least one of said at least three signals is located;
• and
• means for securely transmitting said set of controlling parameters, out-of-band with respect to said output signal to said remote location in response to a received request.

Apparatus having at least one input and an output for use in processing at least three signals, each of said at least three signals being divided into a plurality of portions, each of said portions having an identical format and being delineated in time by portion boundaries, each portion in each of said signals having its portion boundaries aligned with the portion boundaries of a portion in each of the other at least three signals, one portion per signal being received by said apparatus at any instant, the apparatus comprising:

• a cryptographic key generator responsive to a set of controlling parameters for supplying a pseudo-random number sequence, at least one number of said sequence being supplied each time a different portion begins to be received from a predetermined one of said at least three signals by said apparatus;
• means for creating an output signal by supplying as an output portions selected from said portions received by said apparatus;
• and
• means responsive to said pseudo-random number sequence for selecting which of the portions of said at least three signals are supplied as the output of said means for creating;
• means for receiving requests for said set of controlling parameters from at least one remote location at which means for reconstructing at least one of said at least three signals is located;
• and
• means for securely transmitting said set of controlling parameters, out-of-band with respect to said output signal, to said remote location, in response to a received request.

A system for use scrambling at least three original signals and for reconstructing unscrambled versions of said original signals from at least three scrambled signals containing between them all the information of said three original signals, said original signals and said scrambled signals each being divided into a plurality of portions, said system comprising:

• first means responsive to at least a supplied first key variable and a supplied first present internal state for cryptographically generating a first series of portion selection indicators;
• at least three signal selectors, each of said at least three signal selectors having at least an input for receiving said original signals and an output, each selector of said plurality being responsive to said first series of portion selection indicators for selecting a portion of one of said original signals to be supplied to its output to create one of said scrambled signals;
• at least one other signal selector located at said remote location and having at least an input and an output, said other selector receiving versions of all of said at least three scrambled signals as an input and being responsive to said second series of portion selection indicators for selecting a portion to be supplied to its output from one of said at least three scrambled signals;
• at least one communications system for receiving said scrambled signals supplied as outputs by said at least three signal selectors and delivering versions thereof to said at least one other signal selector
• means for receiving requests for said second key variable and said second present internal state from at least said one remote location;
• and
• means for supplying said first key variable and said first present internal state to said first means for cryptographically generating and for supplying, out-of-band with respect to said scrambled signals, in response to a received request said second key variable and said second present internal state to said second means for cryptographically generating at said remote location so that said first series of portion selection indicators and second series of portion selection indicators are identical.

A method of scrambling at least three input signals to create at least three output signals, said method comprising the steps of:

• generating a selection signal cryptographically in response to a set of controlling parameters;
• selecting, in response to the selection signal, a portion of each of said at least three input signals;
• supplying each selected portion as a part of a respective one of said at least three output signals;
• receiving a request for said set of controlling parameters from at least one remote location at which means for reconstructing at least one of said at least three input signals is located;
• and
• transmitting said set of controlling parameters to said means for reconstructing, out-of-band with respect to said at least three output signals, in response to a received request.

A method of scrambling at least three input video signals to create N output video signals. N being three or greater, said method comprising the steps of:

• generating for each of a succession of video frame periods a selection signal having a succession of N elements, each of said elements having a value which identifies a respective different one of said input video signals, the order of the values of said elements within the selection signal being determined cryptographically in response to a set of controlling parameters;
• providing to the $i sup th$ output video signal during each frame period a frame from the input video signal identified by the value of the $i sup th$ element of said selection signal i=1, 2, . . . ,N
• receiving a request for said set of controlling parameters from at least one remote location at which means for reconstructing at least one of said at least three input video signals is located;
• and
• transmitting said set of controlling parameters out-of-band with respect to each output video signal, to said means for reconstructing, in response to a received request.

A method for use in processing at least three signals to obtain an output signal, each signal of said at least three signals being divided into predetermined portions, the method comprising the steps of:

• generating a selection signal cryptographically in response to a set of controlling parameters;
• selecting portions from each signal of said at least three signals, in response to said selection signal, to obtain said output signal;
• receiving a request for said set of controlling parameters from at least one remote location at which means for reconstructing at least one of said at least three signals is located;
• and
• transmitting said set of controlling parameters out-of-band with respect to said output signal to said means for reconstructing, in response to a received request.

A method for use in obtaining an output signal by processing at least three signals that are divided into predetermined portions, the method comprising the steps of:

• generating a cryptographic portion selection signal in response to a set of controlling parameters;
• selecting portions from each of said at least three signals to obtain said output signal in response to said cryptographic portion selection signal;
• receiving a request for said set of controlling parameters from at least one remote location at which means for reconstructing at least one of said at least three signals is located;
• and
• transmitting said set of controlling parameters out-of-band with respect to said output signal to said means for reconstructing, in response to a received request.

A method for use in creating an output signal from at least three input signals that are each divided into predetermined portions, the method comprising the steps of:

• generating a pseudo-random number sequence in response to a set of controlling parameters;
• combining portions of said at least three input signals to create said output signal in response to said pseudo-random number sequence;
• receiving a request for said set of controlling parameters from at least one remote location at which means for reconstructing at least one of said at least three signals is located;
• and
• transmitting said set of controlling parameters out-of-band with respect to said output signal to said means for reconstructing, in response to a received request.

A method for use in scrambling at least three signals having the same defined format comprising the steps of:

• dividing said at least three signals into portions;
• developing a series of output values for a cryptographic function, said values being determined by at least a key variable and a present internal state of said cryptographic function;
• interspersing said portions among one another so as to create at least three new signals, each of said new signals having said defined format wherein said step of interspersing is characterized by being responsive to the output values of said cryptographic function
• receiving a request for said key variable and said present internal state from at least one remote location at which means for reconstructing at least one of said at least three signals is located;
• and
• transmitting said key variable and said present internal state out-of-band with respect to each of said new signals to said means for reconstructing, in response to a received request.