LINB09H3 Lecture Notes - Lecture 7: Fundamental Frequency, Speech Recognition, Speech Synthesis
Document Summary
Insight into sound recognition by humans (perception: audio data of speech is the easiest to obtain. Sound waves: is a travelling pressure fluctuation that propagates through a medium. Some intensities: 0 db = threshold of audibility, 30 db = whispered conversation, 60 db = normal conversation, 110 db = rock concert, 120 db = threshold of pain. Some frequencies: 20, 000 hz = highest perceptible, 265 hz = average child"s speech, 225 hz = average woman"s speech, 120 hz = average man"s speech, 20 hz = lowest perceptible. Properties of speech sounds: speech sounds are not simple sound waves. They are made up of complex waves and noise: when we speak, the release of air passing from our lungs through the glottis causes a complex wave. Spectrum: is a display that shows the amplitude or intensity of each harmonic: shows the intensity of a complex wave at different frequencies.
