Questions tagged [fundamental-frequency]
The fundamental frequency of a periodic or quasi-periodic function is the reciprocal of the shortest period of the periodic function.
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Integer multiples of fundamental period in sine wave
I have a simple question.
Suppose I have a signal : $f(t)=\sin(2\pi \, 25t)$
We know that it's CTFT(continuous time fourier transform) will result in 2 delta's at +- $2\pi\,25$ [rad/sec].
Or ...
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How to get complete fundamental (f0) frequency extraction (python lib librosa.pyin)?
I am running librosa.pyin on a speech audio clip, and it doesn't seem to be extracting all the fundamentals (f0) from the first part of the recording.
https://librosa.org/doc/main/generated/librosa....
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How do I determine if the fundamental period $T_{x}$ exists and if so what it is?
I recently came across this
$$ x(t) = \cos(6t) + \sin(8t) + e^{j2t} $$
signal that I want to find the fundamental period $T_{0}$ and fundamental frequency $\omega_{0} = 2\pi f_{0} = \frac{2\pi}{T_{0}}$...
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Fundamental Frequencies of different instruments
I'm trying to study what differentiates different instruments in terms of frequencies, timbre, etc.
By studying a few different samples of notes, I've come to the conclusion that for flutes the ...
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Near Real Time Algorithm For Approximating Fundamental Frequency
I'd like to analyse the notes being played on a cello C2(65.4Hz) to C6(1046.5Hz) recorded on a PC and thus a likely sampling rate of 44.1kHz. If I can get that to behave then I'd like to be able to ...
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What is a "pitch period"?
The term pitch period appears in the book Speech and Language Processing by Daniel Jurafsy:
As we just said, a pitch-synchronous algorithm is one in which we do
something at each pitch period or ...
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What are some really accurate ways to get the value of a peak (local maximum) given some points around it? (To be used for autocorrelation peaks.)
I have looked everywhere on the internet for this and, surprisingly, haven't found much useful information.
Given 3 or more points closest to a peak (local maximum) what are some of the most accurate ...
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Why do the DTFT and FFT give me completely different results for magnitude at a specific frequency?
I am trying to write a program to compute the magnitude and phase of a specific, non-integer frequency component (i.e. given a sampled finite signal of length $N$, I want to know the magnitude and ...
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Timbre vs sound via oscilloscope
My understanding is that a distinct sound will generate waves of identical amplitude and frequency, but that most things (such as people's voices, music intsruments, etc) produce multiple distinct &...
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what is the relationship between a spectrogram and the uncertainty principle heisenberg? [closed]
what is the relationship between these two things
Perhaps more resolution in a spectrogram is equivalent to knowing more the position of the electron and less resolution is knowing the velocity of the ...
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Change in frequency on differentiation
Is there any possible periodic signal can exist(even mathematically) whose period gets change after differentiation?
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Confusion regarding calculation of fundamental period?
I am reading signal processing first and in chapter 3 ex3.8 i came across an example of fundamental period as shown in attached photo
It apparently shows that signal $$x(t)=\cos^2(4\pi t)$$ has ...
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How to find fundamental frequency of Fourier Series
The original problem is from the Problem Set 7 of MIT OpenCourseware: Find the Fourier series coefficients for
$$
x(t)=sin(10\pi t+\frac{\pi}{6})
$$
What I did is to rewrite it in exponential form $\...
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which features fundamental frequency is correlated?
I'm unable to compute $f_0$ (fundamental frequency) in librosa feature extraction. By ready much in github issues check the second comment. I see that $f_0$ is ...
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Is fundamental frequency information present in speech-shaped white noise?
I am using a so-called speech-shaped stationary white noise, which means so much as a white noise that has been filtered to match the long-term spectrum of a female speaker. The way it was generated ...
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How to determine the phase of a time-sampled periodic signal?
I know this is a rather common and a rather simple problem, but somehow I can't find a solution that is equally simple to understand (and implement).
I have a signal that closely resembles a noisy ...
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Calculate the Standard Deviation of Fundamental Frequency (MFCC)
I'm implementing a gunshot detector following the article "Algorithm for Gunshot Detection Using
Mel-Frequency Cepstrum Coefficients
(MFCC)" (paywall).
In the article, the authors uses 22 features ...
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How to find the fundamental frequency of a discrete signal using partial autocorrelation?
I hope you can help me with this question.
I am trying to calculate the fundamental frequency (to know the beats per minute) of a cardiac pulse signal using partial autocorrelation.
I use a 12-bit ...
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Term for integral multiples of fundamental period?
As we know that a signal has fundamental frequency and integral multiples of fundamental frequency are known as harmonics
I am curious about the term that will be used for integral multiples of ...
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Pitch detection, YIN, pYIN
So here is the "seminal" YIN paper:
Cheveigne A, Kawahara H. - YIN, a fundamental frequency estimator
for speech and music
and the new, improved probabilistic YIN:
Mauch M, Dixon S. - ...
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Find fundamental frequency in short time Fourier Transform
In an implementation of phase vocoder using Python, I found the author get an approximation of the fundamental frequency of STFT using the following formula:
Freq0 = B/A * abs(B/A)
where B is the ...
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Note detection in an audio file.
I am trying to find the given note in an audio file. It has been specifically told that each file contains only one note. So i directly took fft and found the corresponding frequency and then mapped ...
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Discrete Harmonics - Why multiplying digital frequency by k does not get next harmonic
For continuous time $ e^{jk\Omega_0t} $ gives a complete set of orthogonal harmonics for fourier decomposition but for discrete $ e^{jk\omega_0n} $ does not form a complete set orthogonal basis set ...
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how to create a harmonic mask from fundamental frequency?
Using an algorithm that gives the fundamental frequency across time, example https://www.mathworks.com/help/audio/ref/pitch.html (or some other one?)
how would I then use that, to create a harmonic ...
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How do I find the fundamental period of the given signal?
I am having a problem in finding the fundamental period of the signal $x(t)$ given below:
\begin{align}
x(t) &= 2\cos\left(\frac 45 \pi t\right)\sin^2\left(\frac{16}{3} t\right)\\
&= 2\cos\...
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YIN pitch estimation algoritm-simplified explanation [closed]
can someone please explain the steps of YIN pitch detection algorithm in a simple way "especially the last 3 steps".
here is the research paper of YIN algorithm
http://audition.ens.fr/adc/pdf/...
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What are F0 counters in Speech signals? What is represented by F0?
I can't find any dedicated definition for Frequency F0 counters. Can anyone tell me what does F0 exactly mean, I am confused about that.
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Speech Processing applications: stereo data for features
I am working on speech databases that have a stereo format. I want to extract spectral information (Mel-filterbanks, MFCC, LPCC) and also some other prosody features like the fundamental Frequency F0. ...
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Pitch perception - Why does our ear not directly detect the missing fundamental frequency?
My motivation for this question is related to biological phenomenon of our inner ear, so I initially posted in the biology community, but I suspect the answer has a DSP explanation, so I figured this ...
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Octave: Finding the mean fundamental frequency given an audio signal
I have an audio .wav file of someone's speech of which I want to find the mean fundamental frequency. Till now, all I have managed to do is load the data into a vector and (roughly) filter the silence ...
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Finding the fundamental frequency of a periodic signal
Suppose we have the signal $$x(t) = e^{j\omega_1 t} + e^{j\omega_2 t} + e^{j\omega_3 t},$$ where all the frequencies are rationally related (that is, the ratio of any pair of frequencies is a rational ...
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How to change speed of audio samples without changing pitch? [duplicate]
This question may be more appropriate on music stack exchange but since sound is a branch of physics and this is more of a technical question relating to sound waves than a musical question I asked it ...
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Explanation of fundamental filtering's consequences on signal
Can anyone explain why exactly an "Overshooting" phenomena is observed when the fundamental harmonic is removed as seen on the figures? Is it technically right to call this "overshooting" at all ? If ...
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Better way to mute fundamental baseband frequency?
I'm working on a project to monitor the fluctuations and harmonics present on standard 120VAC mains power. I built an adapter that drops the voltage from 120VAC to 12V and then down to 0.5-0.6 VAC ...
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fundamental frequency contour of a syllable [closed]
I have an audio signal and I want to calculate the fundamental frequency contour for each syllable. In the related paper is said that only 9-time points are required. (9 values of frequency contour in ...
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Identify fundamental frequencies in short-period waveform
Maybe I'm being stupid and failing to see something here...
I need to analyse a signal over a relatively short time period (~1-2 cycles for the lowest frequency, perhaps 20-30 cycles for the highest ...
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How to deal with low fundamental when using AMDF for pitch extraction?
I am using the Average Magnitude Difference Function to estimate the fundamental frequency of a quasi-periodic audio signal. The AMDF is defined as
$$ D_n = \frac{1}{N-n}\sum_{k=n}^{N-1}|S_k - S_{k-n}...
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Using FFT to determine frequency [duplicate]
I'm pretty new to digital signal processing, my degree touched on it briefly, but it's interested me since.
I am trying to determine the fundamental frequency of a guitar note played into a mbed ...
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How to represent ratio between harmonics in audio spectrum
I was provided a report where the amplitudes of spectral harmonics have been extracted from several audio files. The amplitudes have been extracted using Audacity's spectrum visualizer, where the ...
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DFT: Basis functions and Significance of dividing frequency by Sample length
A time domain signal can be decomposed into sinusoids which are based on basis functions.
For a N sampled input, a cosine basis function is defined as:
$$C_k[i] = \cos\left[\dfrac{2\pi k i}{N}\right]...
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Advice on autocorrelation via FFT
I have been creating an application in Java that transforms an audio signal and writes it to a midi file.
At first I tried using autocorrelation to find the fundamental frequency. However, I have ...
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DFT sinusoid's fundamental frequency, intuitively
I am trying to understand, intuitively, the mapping of a sinusoidal signal's fundamental frequency from time domain to frequency domain using $\textrm{DFT}$ formula. Given the time domain samples $\{x[...
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