| 摘要 |
<P>PROBLEM TO BE SOLVED: To create masking sound that is free from producing noisy feeling and unnaturalness, using voice collected in a room. <P>SOLUTION: An envelope signal x"<SB>j</SB>(t) for indicating an envelope by each band of a target sound signal x(t) is divided into frames F<SB>i</SB>(i=1,2...), and the frames F<SB>i</SB>(i=1,2...) are divided into frames Fs<SB>m</SB>(m=1,2...) in which an amplitude of a signal x"<SB>j</SB>(t) in the frame F<SB>i</SB>is a threshold Th1 or less, or a threshold Th2 or more, and frames Fr<SB>l</SB>(l=1,2...) in which the amplitude of the signal x"<SB>j</SB>(t) is the threshold Th1 or more, and the threshold Th2 or less. Then, a noise signal C<SB>j</SB>(t) is multiplied by an envelope signal y<SB>j</SB>(t) in which only an arrangement order is changed, in the frames F<SB>i</SB>(i=1,2...) of the envelope signal x"<SB>j</SB>(t), and a masking sound signal M(t) created on the basis of the multiplication results, is output to a room 92. <P>COPYRIGHT: (C)2010,JPO&INPIT |
