A method and apparatus for inserting a low frequency watermark into a compressed data stream carrying compressed content is disclosed. Examples are given for multiplying a 3-bit binary number by a 2-bit binary number; however, there are no limitations to the bit-widths of the numbers to be multiplied. The rotor signals are indicative of the position of each rotor of the aircraft. Thereafter, the fuse element portions are formed at the predetermined locus by, for example, stamping. A radiation-transmissive covering layer with an absorber is applied to the encapsulation. Each identified self-describing fragment includes hierarchical context of a portion of the input text.