Spectral modeling synthesis

Spectral Modeling Synthesis or simply SMS is an Acoustic_model approach for speech and other signals.

SMS considers sounds as a combination of harmonic content and noise content. Harmonic components are identified based on peaks in the frequency spectrum of the signal, normally as found by the short-time Fourier transform. The signal that remains following removal of the spectral components, sometimes referred to as the residual, is then modeled as white noise passed through a time-varying filter. The output of the model, then, are the frequencies and levels of the detected harmonic components and the coefficients of the time-varying filter.

Intuitively, the model can be applied to many types of audio signals. Speech signals, for example, include slowly-changing harmonic sounds caused by vibration of the vocal cords plus wideband, noise-like sounds caused by the lips and mouth. Musical instruments also produce sounds containing both harmonic componenents and percussive, noise-like sounds when the notes are struck or changed.

See also

• Speech coding
• CELP
• Source-filter model of speech production
• Frequency_modulation_synthesis

References

Xavier Serra (2003). Spectral-Modeling-Synthesis-Past-and-Present.pdf "Spectral Modeling Synthesis: Past and Present" (PDF). p. 20. {{cite web}}: Check |url= value (help); Cite has empty unknown parameters: |accessdaymonth=, |month=, and |coauthors= (help); Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)

Xavier Serra. "Spectral Modeling Synthesis Homepage" (HTML). {{cite web}}: Cite has empty unknown parameters: |accessdaymonth=, |month=, and |coauthors= (help); Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help)

Julius O. Smith III (28). "Spectral Modeling" (HTML). {{cite web}}: Check date values in: |date= and |year= / |date= mismatch (help); Cite has empty unknown parameters: |accessdaymonth= and |coauthors= (help); Unknown parameter |accessmonthday= ignored (help); Unknown parameter |accessyear= ignored (|access-date= suggested) (help); Unknown parameter |month= ignored (help)