1. A method for protecting a digital signal, comprising the steps of: providing a digital signal comprising digital data and file format information defining how the digital signal is encoded; creating a predetermined key to manipulate the digital signal; manipulating the digital signal using the predetermined key to generate at least one permutation of the digital signal parameterized by the file format information defining how the digital signal is encoded; wherein the predetermined key comprises one or more mask sets having random or pseudo-random series of bits; and validating the one or more mask sets either before or after manipulating the file format information using the predetermined key.