| CPC H04R 3/007 (2013.01) [H04R 29/001 (2013.01); H04R 29/008 (2013.01)] | 7 Claims |

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1. A semiconductor device comprising:
a pulse-width modulation circuit configured to pulse-width modulate a signal based on a first pulse-code modulated signal that is a sound source signal, and output a first pulse-width modulated signal;
a first conversion circuit configured to convert a second pulse-width modulated signal based on the first pulse-width modulated signal into a second pulse-code modulated signal; and
a comparison circuit configured to:
perform a wavelet packet analysis on the first pulse-code modulated signal to convert the first pulse-code modulated signal into a first comparison target signal by an inversely convertible conversion method;
perform the wavelet packet analysis on the second pulse-code modulated signal to convert the second pulse-code modulated signal into a second comparison target signal by the conversion method; and
compare the first comparison target signal with the second comparison target signal to calculate a correlation value therebetween.
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