Abstract: A computer program obfuscating system including a processor to provide a computer program including at least one computer program variable, and add an opaque predicate to the computer program to obfuscate the computer program so that the opaque predicate added to the computer program comprises at least one polynomial including a polynomial P, during execution of the obfuscated computer program, the polynomial P is evaluated yielding at least one result including a first result R1, and during execution of the obfuscated computer program, the opaque predicate is evaluated based on the at least one result R1 such that a decision as to whether or not to perform the first command is dependent upon comparing the first result R1 to at least one value in accordance with a predetermined mathematical relationship. Related apparatus and methods are also included.

Abstract: In one embodiment, a watermark is embedded in a sequence of video frames, for each one of the video frames, a set of N rectangular patches, two palettes of pixel values in a selected color space, such that the two palettes are denoted as P0 and P1, and P0?P1, and in each one of the N patches a processor which chooses one of P0 and P1 according to a value of a payload bit to be encoded, a calculator which calculates one of a variance of pixel values in the frame, and edginess for the pixel values in the frame, thereby determining a calculated value, and a processor which determines if the calculated value is beneath a given threshold value, if the calculated value is beneath the given threshold value the processor is operative to calculate a function of the pixel values, the closest value to a result of the calculation of the function in the chosen palette is chosen, and a replacer which replaces the pixel values within the patch with the chosen closest value.

Abstract: In one embodiment, a watermark is embedded in a sequence of video frames, for each one of the video frames, a set of N rectangular patches, two palettes of pixel values in a selected color space, such that the two palettes are denoted as P0 and P1, and P0?P1, and in each one of the N patches a processor which chooses one of P0 and P1 according to a value of a payload bit to be encoded, a calculator which calculates one of a variance of pixel values in the frame, and edginess for the pixel values in the frame, thereby determining a calculated value, and a processor which determines if the calculated value is beneath a given threshold value, if the calculated value is beneath the given threshold value the processor is operative to calculate a function of the pixel values, the closest value to a result of the calculation of the function in the chosen palette is chosen, and a replacer which replaces the pixel values within the patch with the chosen closest value.

Abstract: In one embodiment, a system including a processor is operative to receive a content item including a watermark encoding a series of data values of an output stream of a linear feedback shift register initialized with a seed including an information element and an assurance value, the shift register having a plurality of states each including a first and second value, identify at least part of the watermark in the content item, extract at least some of the data values from the at least part of the identified watermark, process at least some of the extracted data values yielding the initial state of shift register, and authenticate the first value of the initial state using the second value of the initial state in order to confirm that the first value is indeed the information element included in the seed processed by the shift register.

Abstract: In one embodiment, a watermark is embedded in a sequence of video frames, for each one of the video frames, a set of N rectangular patches, two palettes of pixel values in a selected color space, such that the two palettes are denoted as P0 and P1, and P0?P1, and in each one of the N patches a processor which chooses one of P0 and P1 according to a value of a payload bit to be encoded, a calculator which calculates one of a variance of pixel values in the frame, and edginess for the pixel values in the frame, thereby determining a calculated value, and a processor which determines if the calculated value is beneath a given threshold value, if the calculated value is beneath the given threshold value the processor is operative to calculate a function of the pixel values, the closest value to a result of the calculation of the function in the chosen palette is chosen, and a replacer which replaces the pixel values within the patch with the chosen closest value.

Abstract: A Headend system including a encoder to encode input data yielding a plurality of data packets, each of the packets having a header and a payload, a post encoding processor to identify ones of the data packets having a payload with a suspected known plaintext, and modify at least some of the identified packets, and an encryption processor to encrypt at least some of the data packets yielding encrypted data packets. Related apparatus and methods are also described.

Abstract: In one embodiment, a system including a processor is operative to receive a content item including a watermark encoding a series of encrypted bits deriving from encrypting an information element multiple times, extract at least some encrypted bits from at least part of the watermark, decrypt a series of N bits using a first key yielding a first value, the series of N bits including Q bits of the encrypted bits and K, greater than, or equal to zero, guessed bits, re-encrypt the first value using a second key yielding a second value, and compare at least part of the second value to M bits of the encrypted bits to determine if at least part of the second value matches the M bits in order to provide a level of confidence that the first value is the information element which was encrypted and embedded as the watermark.

Abstract: In one embodiment, a system including a processor is operative to receive a content item including a watermark encoding a series of data values of an output stream of a linear feedback shift register initialized with a seed including an information element and an assurance value, the shift register having a plurality of states each including a first and second value, identify at least part of the watermark in the content item, extract at least some of the data values from the at least part of the identified watermark, process at least some of the extracted data values yielding the initial state of shift register, and authenticate the first value of the initial state using the second value of the initial state in order to confirm that the first value is indeed the information element included in the seed processed by the shift register.

Abstract: A method including determining a position of each glyph in an image of a text document, identifying word boundaries in the document thereby implying the existence of a first plurality of words, preparing a first array of word lengths based on the first plurality of words, preparing a second array of word lengths based on a second plurality of words of a text file including a certain text, comparing at least part of the first array to at least part of the second array to find a best alignment between the first and second array, deriving a layout of at least part of the certain text as arranged in the image of the text document at least based on the best alignment and the position of at least some of the glyphs in the image. Related apparatus and methods are also described.

Abstract: In one embodiment, a system including a processor is operative to receive a content item including a watermark encoding a series of encrypted bits deriving from encrypting an information element multiple times, extract at least some encrypted bits from at least part of the watermark, decrypt a series of N bits using a first key yielding a first value, the series of N bits including Q bits of the encrypted bits and K, greater than, or equal to zero, guessed bits, re-encrypt the first value using a second key yielding a second value, and compare at least part of the second value to M bits of the encrypted bits to determine if at least part of the second value matches the M bits in order to provide a level of confidence that the first value is the information element which was encrypted and embedded as the watermark.

Abstract: A method including determining a position of each glyph in an image of a text document, identifying word boundaries in the document thereby implying the existence of a first plurality of words, preparing a first array of word lengths based on the first plurality of words, preparing a second array of word lengths based on a second plurality of words of a text file including a certain text, comparing at least part of the first array to at least part of the second array to find a best alignment between the first and second array, deriving a layout of at least part of the certain text as arranged in the image of the text document at least based on the best alignment and the position of at least some of the glyphs in the image. Related apparatus and methods are also described.

Abstract: A computer program obfuscating system including a processor to provide a computer program including at least one computer program variable, and add an opaque predicate to the computer program to obfuscate the computer program so that the opaque predicate added to the computer program comprises at least one polynomial including a polynomial P, during execution of the obfuscated computer program, the polynomial P is evaluated yielding at least one result including a first result R1, and during execution of the obfuscated computer program, the opaque predicate is evaluated based on the at least one result R1 such that a decision as to whether or not to perform the first command is dependent upon comparing the first result R1 to at least one value in accordance with a predetermined mathematical relationship. Related apparatus and methods are also included.

Abstract: A method and system for fingerprinting a content item is described, the content item including a set of content item elements E, providing information uniquely associated with a single user including a string of bits S0, parsing S0 into a plurality of substrings which are functions of S0, providing a matrix of content item replacement elements, each row of which includes, for each member of E, an array of content item replacement elements for Ei, uniquely associating each substring of S0 so that for every substring there exists a corresponding element of E, for every substring, replacing at least one instance of the corresponding element E in the content item with one substitute matrix element for the corresponding substring, and outputting a replacement content item including the result of the replacing, the substitute matrix elements being chosen according to at least one similarity criterion.

Abstract: A method for distributing information includes distributing an item of encrypted information to a plurality of clients and distributing respective key-shares to the clients, such that each client will require a key-share that has been distributed to at least one other client in order to reconstruct a key for decrypting the encrypted information. Upon receiving from a first client a report that a second client requested and received a respective one of the key-shares from the first client, a record of a delivery of the item to the second client is made responsively to the report.

Abstract: A Headend system including a encoder to encode input data yielding a plurality of data packets, each of the packets having a header and a payload, a post encoding processor to identify ones of the data packets having a payload with a suspected known plaintext, and modify at least some of the identified packets, and an encryption processor to encrypt at least some of the data packets yielding encrypted data packets. Related apparatus and methods are also described.

Abstract: A method and system for determining whether user accounts in a client-server architecture are legitimate is described, the method and system including determining a first integer value, hereinafter denoted N, and a second integer value, hereinafter denoted K, such that K<N, receiving a request at a server from one client device of a plurality of client devices, the request including a unique user identification and a password, the request being a request to access an object, the unique user identification and password being associated with a particular user, sending from the server, at least K times, to one client device of the plurality of client devices a share to be stored in a state object stored on the one client device to which any share is sent on behalf of the server, verifying at the server that one client device of the plurality of client devices has at least K stored shares in the state object, as a positive result of the verifying, flagging in a database that a user account associated with the

Abstract: A method and system for fingerprinting a content item is described, the and system method include providing the content item, the content item including a set of content item elements, the set of content item elements denoted E, such that E={E1, E2, Ei, Em}, providing information uniquely associated with a single user, the information including a string of bits, hereinafter denoted S0, parsing S0 into a plurality of subsequences of strings of bits, hereinafter denoted S1,, Sn, the parsing being performed such that S0 equals a function of S1,, Sn, providing a matrix of content item replacement elements, the matrix denoted R, each row of matrix R including, for at least each one of n members of set E, an array of content item replacement elements for Ei denoted Ri, such that Ri={Ri1, Rij}, uniquely associating each one of S1, Sn with one matrix element of matrix R, so that for every one of S1,, Sn there exists a corresponding element of E, for every one of S1,, Sn replacing at least one instance of the correspo