Scrambler, descrambler and recording medium

摘要

A scrambler(1) includes a PN1n selector(3) for selecting one pseudo-random signal PN1n from a predetermined plurality of pseudo-random signals based on an input scramble key n, a spectrum shaper(5) for shaping the spectrum of the selected pseudo-random signal PN1n, an adder(7) for adding the spectrum-shaped PN1n to an audio signal, a PN2n generator(9) for generating a pseudo-random signal PN2n based on the scramble key n, and a scrambling circuit(11) for scrambling the audio signal based on the pseudo-random signal PN2n. A descrambler(31) includes a PN1n detector(33) for detecting PN1n embedded into the audio signal and for outputting the scramble key n, a PN2n generator(35) for generating the pseudo-random signal PN2n based on the scramble key n, and a descrambling circuit(37) for descrambling the audio signal based on the pseudo-random signal PN2n.