System and method for automatic classification of speech based upon affective content

A method for classifying the affective content of speech, comprising the steps of:

• analyzing a portion of a speech signal to determine the mel-frequency cepstral coefficients for the speech signal, and measuring the difference in said coefficients from frame to frame of said portion of the speech signal to determine changes in the spectral envelope of the speech signal over time;
• analyzing said portion of the speech signal to determine values for other features of said portion of the speech signal which are based upon the characteristics of the speech signal other than its spectral envelope;
• providing said changes in the spectral envelope and said values of the other features to a classifier;
• and
• labelling said portion of the speech signal as belonging to one of a predetermined set of classes of affective content for which said classifier has been trained.

A method for classifying the affective content of speech, comprising the steps of:

• analyzing a portion of a speech signal to determine values for multiple features of said portion of the speech signal which are based upon the pitch of the speech signal;
• analyzing said portion of the speech signal to determine the mel-frequency cepstral coefficients for the speech signal, and measuring the difference in said coefficients from frame to frame of said portion of the speech signal to determine changes in the spectral envelope of the speech signal over time;
• providing said values of the pitch-based features and said envelope changes to a classifier;
• and
• labelling said portion of the speech signal as belonging to one of a predetermined set of classes of affective content for which said classifier has been trained.

A system for classifying speech according to its affective content, comprising:

• a pitch analyzer which determines values for features of a portion of a speech signal which are based upon the pitch of the speech signal;
• a spectral shape analyzer which determines the mel-frequency cepstral coefficients for the speech signal, and measures the difference in said coefficients from frame to frame of said portion of the speech signal to determine changes in the spectral envelope of the speech signal over time;
• and
• a classifier which receives said pitch-based feature values and said changes in the spectral envelope, and labels said portion of the speech signal as belonging to one of a predetermined set of classes of affective content for which said classifier has been trained.

A system for classifying speech according to its affective content, comprising:

• a spectral shape analyzer which determines the mel-frequency cepstral coefficients for the speech signal, and measures the difference in said coefficients from frame to frame of the speech signal to determine changes in the spectral envelope of a speech signal over time;
• a second analyzer which determines values for other features of the speech signal which are based upon the characteristics of the speech signal other than its spectral envelope;
• and
• a classifier which labels the speech signal as belonging to one of a predetermined set of classes of affective content in accordance with said changes in spectral envelope and said other feature values.

A system for classifying speech according to its affective content, comprising:

• a pitch analyzer which determines values for multiple features of a speech signal which are based upon the pitch of the speech signal;
• a spectral shape analyzer which determines the mel-frequency cepstral coefficients for the speech signal, and measures the difference in said coefficients from frame to frame of the speech signal to determine changes in the spectral envelope of the speech signal over time;
• and
• a classifier which labels speech signal as belonging to one of a predetermined set of classes of affective content in accordance with said pitch-based feature values and said spectral envelope changes.