Time-frequency methods provide more viable solutions than Fourier methods for signals that are shorter in time and not necessarily periodic. Methods such as Wavelet and Gabor transforms are considered to be T-F techniques.
Questions tagged [time-frequency]
87 questions
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To apply window function on Wigner-Ville Distribution in Matlab
We were thinking here how to create Hamming-64 window of overlap 64.
It is done by
h = hamming(64);
h2 = hamming(38);
h = conv(h, h2);
Now, we are thinking how you can apply this window function to the resulted variabels of the Wigner-Ville…
Léo Léopold Hertz 준영
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To scale values from Wigner-Ville Distribution to real range in Matlab
I run by using the function tfrwv.m in Time-Frequency Toolbox
[B,T,F] = tfrwv(data, 1:length(data), length(data), 1);
B(1:130, :) = 0; % remove the duplicate part of the distribution
imagesc(T, F, abs(B));
colormap(hot);
xlabel('t…
Léo Léopold Hertz 준영
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How to determine frequency in time dimension using FFT and IFFT on 3D Matrix
Currently, I working on a assignment to obtain few frames from a movie file played in Matlab. A 3D Matrix was created in parameter X,Y and time. But I been asked to determine the frequency in time by using FFT and IFFT.
My problem is how to plot the…
E.Lee
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Count Parallel port input frequency - C#
I have to count the input frequency of the parallel port at Pin no.13, comming from a 555 timer IC, the real frequency should be around 3-4 Hz (ON Pulse). I have tried several codes, several times but every time those are giving different values. I…
Farid-ur-Rahman
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Predicting occurence of events
If the sampling time interval is 10 sec and 3 events occur during the interval the first event occurs at the 4th sec , the second event occurs at the 7th sec and 8th event occurs at 8sec. Is there a way i could predict when the next event occurs ??…
Rajeshwar
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Crontab function scheduler in seconds timer
How to set any postgres function in crontab with frequency of seconds?
Thank you in advance.
Tried searching for seconds timer scheduling. But looks like postgres / crontab doesn't support for seconds setup. only minute, hour, day, etc options are…
Prachita Raut
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Is there a way to parse time so that it executes code only once in a given timeframe?
Let's say I'm listening whether a random event has happened. (Specifically I'm doing this via a webhook. After I receive a webhook, I execute code)
I do not want my webhook event to execute code more than once in a given timeframe, e.g. 30…
CryPtoSmartGuy420
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Existing library/algorithm for episodic frequency detection and prediction in a time series?
I'm working with podcast RSS feeds in Python. Are there any existing libraries or algorithms to detect and predict periodic release schedules, given a series in time?
For example, if five items in an RSS feed had the following timestamps:
Fri, 20…
xd1936
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fscanf (filepointer, "%d\n%lg\n", sig_length, sample_rate); how to interpret it?
I have an audio format conversion from an scientific audio filetype that existed prior to the internet (called TFD v1) an uncompressed uncomplicated simple raw array of sample values... In the get_signal() function on this page, i don't know how the…
bandybabboon
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Time/frequency color map in python
Is there in native Python 3.X library or in scipy/numpy/matplolib libraries a function or their short set which could help me to draw a plot similar to this one(?):
What would be an efficient way to achieve something like this? Thank you in…
bluevoxel
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FFT: time-domain features to frequency domain
I am not from Physics or electrical engineering, so the answers I read related to my only confused me the more. So I asked this case-specific question.
I work with a sensor data (time series). The data consists of sensor values for 4 quantities (4…
Amina Umar
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