Patent ID: 8050931

Claim:
A sound masking system comprising: a sound pickup section that picks up a sound and generates an original sound signal corresponding to the picked-up sound; a speech utterance speed signal generation section that generates a speech utterance speed signal, indicative of a speech utterance speed of the picked-up sound, on the basis of the original sound signal generated by said sound pickup section; a table where the speech utterance speed and a frame length for dividing the sound signal into predetermined time lengths are stored in association with each other; a readout section that reads out from said table the frame length corresponding to the speech utterance speed signal generated by said speech utterance speed signal generation section; and a scramble section that copies the original sound signal, generated by said sound pickup section, into sound signals of a plurality of channels, divides the original sound signal of each of the channels into a plurality of frames on the basis of the frame length read out by said readout section, reconfigures the sound signal of each of the channels so as to change a time series of the plurality of frames of the channel and then outputs the reconfigured sound signal of each of the plurality of channels as a scrambled sound signal.