applies pitch shifting to audio by the ratio r, shifting every frequency to .
Details and Options
- AudioPitchShift shifts the pitch of the input audio signal without affecting the duration.
- The frequency ratio r can be given as a pitch interval, including:
Quantity[oct,"octaves"] correspond to Quantity[sem,"semitones"] correspond to
- AudioPitchShift takes a PartitionGranularity option that controls the partitioning of audio, used for the computation of the short-time Fourier transform.
- By default, a phase vocoder algorithm is used. Select Method->"Speech" to use an algorithm tailored for speech signals. In this case, while the fundamental frequency is changed, the formants of the signal are not modified.
Examplesopen allclose all
AudioPitchShift can be used to change the pitch of a harmonically complex sound without altering its timbre and timing:
Use Method->"Speech" for speech signals to shift the pitch while maintaining other voice characteristics:
By default, HannWindow is used.
Extract the mean frequency with AudioLocalMeasurements:
Properties & Relations (2)
AudioPitchShift shifts each frequency f in the signal by an amount proportional to the frequency itself (f'=f×shift), thus preserving the timbre in the shifted signal:
AudioFrequencyShift shifts every frequency f by the same amount (f'=f+shift), changing dramatically the timbre in the shifted signal:
AudioPitchShift changes the pitch without altering the timing:
Possible Issues (2)
Using Method->"Speech" for non-speech signals may not sound as expected:
Wolfram Research (2016), AudioPitchShift, Wolfram Language function, https://reference.wolfram.com/language/ref/AudioPitchShift.html (updated 2020).
Wolfram Language. 2016. "AudioPitchShift." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2020. https://reference.wolfram.com/language/ref/AudioPitchShift.html.
Wolfram Language. (2016). AudioPitchShift. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/AudioPitchShift.html