Abstract: A voice encryption device including a pseudorandom number generator that generates a key data stream responsive to a cryptographic key; a shift register that sequentially stores a sequence of voice data as a block of voice data; a selector that selects pieces of voice data from among the block of voice data stored by the shift register and provides a rearranged block of voice data including the selected pieces of voice data as initial pieces of voice data in the rearranged block of voice data, responsive to a key data value from among the key data stream; and a combiner that combines the rearranged block of voice data provided from the selector with the block of voice data to generate an encrypted block of voice data.

Abstract: A message can be encoded in an image file by mapping at least one bit of the message onto each sub-unit of the image file, and adjusting a distinguishable characteristic of each sub-unit according to the corresponding bit to produce a modified image file. The message can be decoded from the message file by comparing each sub-unit of the modified image file with a corresponding sub-unit of the original image file, and identifying at least one bit of the message based on each comparison.

Abstract: A method of enciphering information includes generating five index values by performing modulo division on a 32-bit binary input value, identifying five 8-bit output patterns based on the five index values, and enciphering or deciphering five bytes of text using the five 8-bit output patterns.

Abstract: A method of enciphering information comprises generating five index values by performing modulo division on a 32-bit binary input value, identifying five 8-bit output patterns based on the five index values, and enciphering or deciphering five bytes of text using the five 8-bit output patterns.

Abstract: A message can be encoded in an image file by mapping at least one bit of the message onto each sub-unit of the image file, and adjusting a distinguishable characteristic of each sub-unit according to the corresponding bit to produce a modified image file. The message can be decoded from the message file by comparing each sub-unit of the modified image file with a corresponding sub-unit of the original image file, and identifying at least one bit of the message based on each comparison.

Abstract: A secure transaction system in accordance with one exemplary embodiment comprising a terminal; a secure access module coupled to the terminal; and a secure embedded device coupled to the secure access module during a transaction; wherein the business logic for controlling flow of the transaction is contained within the secure access module and the secure embedded device.