Abstract: A system for authenticating data of interest includes a digest locator engine capable to locate a first and a second digest result in a data file, including a set of data; a first digest creator capable to create, using a first digest function, a first digest of the set of data, the first digest function being identical to a digest function used to create the first digest result; a second digest creator capable to create, using a second digest function that is incompatible with the first digest function, a second digest of the set of data, the second digest function being identical to a second digest function used to create the second digest result; and a digest comparator engine, communicatively coupled to the digest locator, first digest creator and the second digest creator, capable to compare the first and second created digests with the first and second located digest results respectively.

Abstract: A system enables encoding of a removable mark into digital data, and decoding of the mark from the digital data. The system comprises an encoder and a decoder. The encoder includes a target area locator for locating in digital data a predetermined pattern of values that represents a flat area, and a marker for modifying values in the flat area to encode a mark into the flat area. The decoder attempts to extract the mark from the digital data. The decoder includes a mark area locator for locating a predetermined pattern of values in digital data, and an unmarker coupled to the mark area locator for examining the values to determine the state of each value and extract an embedded mark from the predetermined pattern of values.

Abstract: A system enables encoding of a removable mark into digital data, and decoding of the mark from the digital data. The system comprises an encoder and a decoder. The encoder includes a target area locator for locating in digital data a predetermined pattern of values that represents a flat area, and a marker for modifying values in the flat area to encode a mark into the flat area. The decoder attempts to extract the mark from the digital data. The decoder includes a mark area locator for locating a predetermined pattern of values in digital data, and an unmarker coupled to the mark area locator for examining the values to determine the state of each value and extract an embedded mark from the predetermined pattern of values.

Abstract: A system enables encoding of a removable mark into digital data, and decoding of the mark from the digital data. The system comprises an encoder and a decoder. The encoder includes a target area locator for locating in the digital data a flat area having a flatness value n, and includes a marker for using the flatness value n to encode a mark into the flat area. The decoder attempts to extract a mark that includes a plateau and a core from digital data. The decoder includes a mark area locator for using a flatness value n to search digital data for a possible plateau, an unmarker coupled to the flat area locator for decoding a possible core upon locating a possible plateau and for using the flatness value n to replace the possible core with possible original data, and an authenticator coupled to the unmarker for examining the possible core for accuracy.