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Questions tagged [ifft]

NOTE: please use the FFT tag instead. The FFT is a type of algorithm for quickly computing the Inverse Discrete Fourier Transform.

The IFFT is an FFT algorithm with some different initial permutation of data samples, and often an additional normalization, such that the algorithm computes the IDFT rather than the DFT. The FFT and IFFT are always implemented by the same code.

Related topics include , , , .

More information on the IFFT can be found in the Wikipedia article on the FFT

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IFFT with WebAudio Analyser

Is there any way to perform an IFFT using the WebAudio Analyser node? I notice there is a getByteTimeDomainData method, but how would I feed it magnitude and phase arrays? Do I connect an AudioBuffer source to it containing interleaved mag and…
user1821738
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how to transform frequency domain into time domain

I had created a 3 three different frequency signal and filter out the signal i don't want. But when i using ifft in matlab, it shows a wrong graph.How to transform my frequency domain spectrum back into my 3 second time domain graph? Below my code…
Ambbie
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Getting Data back from Filtered FFT

I have applied an FFT to some data that I'd like to process using Matlab. The resulting frequencies are quite noisy, so I have applied a moving average filter to the frequency/amplitude vectors. Now I am interested in getting the time domain data…
PennyFarthing
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ifft in matlab and numpy give different results

I have another question. Quite similar to the other that i already asked (and got great help - thanks again). Unfortunately the solution from the other thread does not work here:…
Chris
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How to control the length and sampling time of the output of ifft in MATLAB?

I have data in frequency domain that looks like this: This means I have a vector Y that contains the amplitude for the frequency points in the vector x. For example f = [0 1 2 3 4 5 6 7 8 9 10] Y = [0 0 0 0 0 1 0 0 0 0 0] Performing an inverse…
Rambaldi
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Do I want to (i)fft by gnuradio-companion?

To dark blue input ,Arrow becomes red. Hi, everyone! I use gnuradio-companion 3.7.11 with ubuntu 18.04.2 lts, I want to do (I)FFT, but when both input and output specify complex, Even if the complex is dark blue and complex is light blue, It becomes…
sunao
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Store the output of the Python matplotlib function of pcolormesh and reconstruct it

I am gonna apply Short Time Fourier Transform on this signal and plot the results using pcolormesh function. Then, I want to use Inverse Short Time Fourier Transform to reconstruct the signal. My question is how to use the output of the pcolormesh…
Rahman
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CUFFT wrong result for batch 1D ifft

I am new to CUDA and CUFFT, when I was trying to recover the fft result of cufftExecC2R(...) by applying the corresponding cufftExecC2R(...), it went wrong, the recovered data and the original data is not identical. Here is the code, the cuda…
shawnwinder
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FFT or IFFT lose data

I am doing FFT and IFFT with audio signal. The following is the code that i am using. But my question is before FFT, it extracts 1 byte from short array. As you know short is 2 bytes. why it is doing it? Because of the extraction, After…
Knowledge Drilling
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I have the equation in frequency domain; How to go back in time and space domain with IFFT?

I have the solution of an equation (analytic solution) in frequency domain; How to go back in time and space domain with IFFT? I try to input frequency samples (w, xi) in the equation and then to IFFT the results. However I am not sure if I did it…
Edmond Muho
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Fidelity of sound created from frequency domain data

I know it is possible to create .wav file from frequency domain data (magnitude + phase) but I would like to know how close would that be to the real(orginal) sound ? Does it depend on the frequency step for example (or something else). Second…
Ragnar
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Pattern Recognition in Matlab

first I am not sure here is the right place to ask this question yet I have a question about image processing. I am trying to write a pattern recognition code in Matlab. I have an object input which is 256x256 pixels raw data includes "ABCD" capital…
Serdar
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How can I recover original complex signal after fft?

There is a simple code in below that I prepared for understandable a question. My purpose is recover original complex signal after FFT process in Matlab. As you understand from code, I created 1x128 complex vector. After I implement IFFT process…
PALES
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FFT results interpretation

I used excel to transform my time domain data to the frequency domain, the results I got were complex numbers, of which I obtained the absolute value using imabs in excel. Now I am confused, are these absolute values the amplitudes in certain…
Fahim Mumand
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coding a deconvolution using python

Before I begin I have to tell you that I have zero knowledge about DSP in python. I want to deconvolute two sound signals using python so that I can extract the room impulse response, the input signal being a sinesweep and the output a record of…
Med Morcia
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