Sound wave signal processing apparatus and sound wave detection method

A sound wave signal processing apparatus comprising:

• an extraction unit configured to extract, from a sound wave signal, a plurality of frequency signals indicating respective frequency components of a plurality of frequency bands including different set frequencies;
• a setting unit configured to set a set frequency of the extraction unit on a basis of a comparison result between output levels of the frequency signals of the different set frequencies extracted by the extraction unit;
• and
• a detection unit configured to detect, when a difference between output levels of frequency signals of two set frequencies extracted by the extraction unit is smaller than a predetermined difference, a formant frequency band including a formant frequency in the sound wave signal on a basis of a set frequency having a higher output level of the output levels of the frequency signals of the two set frequencies extracted by the extraction unit.

A sound wave detection method comprising:

• extracting, by an extraction unit, from a sound wave signal, a plurality of frequency signals indicating respective frequency components of a plurality of frequency bands including different set frequencies;
• updating the different set frequencies when a comparison result between output levels of the frequency signals of the different set frequencies extracted by the extraction unit does not satisfy a predetermined condition;
• performing peak determination on a basis of a comparison result group and a setting history of the set frequencies when the comparison result satisfies the predetermined condition;
• and
• detecting a formant frequency band including a formant frequency in the sound wave signal on a basis of a result of the peak determination and a frequency characteristic of the extraction unit.