1. A method for encoding a message into digital information, the digital information including a plurality of digital blocks, comprising the steps of: transforming each of the digital blocks into the frequency domain using a fast Fourier transform; identifying a plurality of frequencies and associated amplitudes for each of the transformed digital blocks; selecting a subset of the identified amplitudes for each of the digital blocks using a primary mask from a key; choosing message information from the message using a transformation table generated with a convolution mask; and encoding the chosen message information into each of said transformed digital blocks by altering the selected amplitudes based on the chosen message information.