# Questions tagged [zero-padding]

Zero padding consists of extending a signal (or spectrum) with zeros to extend its time (or frequency band) limits.

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### Why should I zero-pad a signal before taking the Fourier transform?

In an answer to a previous question, it was stated that one should zero-pad the input signals (add zeros to the end so that at least half of the wave is "blank") What's the reason for this?
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### Frequency-domain zero padding - special treatment of X[N/2]

Suppose we wish to interpolate a periodic signal with an even number of samples (e.g. N=8) by zero-padding in the frequency domain. Let the DFT X=[A,B,C,D,E,F,G,H] ...
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### Why do we say that “zero-padding doesn't really increase frequency resolution”

Here is a sinusoid of frequency f = 236.4 Hz (it is 10 milliseconds long; it has N=441 points at sampling rate ...
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### Sense of zeropadding in a time domain

I have the task related to Radon transform which contains a subtask which uses resampling by means of DFT. Let's consider the non-periodical discretized signal (Fig.1) (for example the string of ...
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### Zero Padding in FFT

whats is the effect of pading zeroes to a sequence in FFT? for eg: x[n]=[2 3 4 5] corresponds to X[K]=[14 -2+2i -2 -2-2i] while x[n]=[2 3 4 5 0 0 0 0] corresponds to X[K]=[14 0.58-9.65i -2+2i -3.414+...
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### What happens when N increases in N-point DFT [duplicate]

I am curious about DFT, and I wrote a simple MATLAB code to test what happens when $N$ increases. I took a rectangular signal with length $L=15$, an then found th DFT of 16, 32 and 64 points. I looked ...
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### How does zero-padding affect the magnitude of the DFT?

Let's simulate sinusoids of two frequencies using the following Matlab code: ...
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I would like to know what are the advantages/disadvantage of zero padding with respect to frequency measurement and amplitude measurement
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### FFT: Removed padded zeroes?

I have an application where I do this: DFT->Filter->IDFT on a range For computational performance I'm zero-padding my FFT to a power of two, but when I ...
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### How Exactly Does MATLAB Zero Pad Signal?

I am doing some massive number crunching in MATLAB which involves millions of PSD estimations. Each data segment has length 41. So I have been using the multi-taper method with ...
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### How Much Zero Padding Do We Need to Perform Filtering in the Fourier Domain?

Consider an $M\times N$ image $f$ and an $G \times K$ filter $h$. Given that convolution in the spatial domain corresponds to multiplication in the Fourier domain, then we can perform a convolution of ...
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### How to remove the boundary effects arising due to zero padding in scipy/numpy fft?

I have made a python code to smoothen a given signal using the Weierstrass transform, which is basically the convolution of a normalised gaussian with a signal. The code is as follows: ...
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### Is there a rule of thumb for zero padding in image processing?

I see there are a lot of answers on why zero padding is necessary and how it avoids wrapping around the sides of images. However is there a rule of thumb on how much padding will be good for the image ...
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### Zero-padding a spectrum, how to split the middle bin?

When a complex digital signal is converted to its spectrum through an FFT, the result will contain a series op positive and negative frequencies. That is, when the spectrum has N bins. Bin 0 will be ...
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### Is digital up and down sampling linear/causal/time-invariant?

So I am trying to determine whether the process of up sampling (zero padding) and downsampling are linear, causal and/or time-invariant. Based on some resources I found online, I am under the ...
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### How do I calculate peak amplitude of the signal components after zero padding and FFT?

I am learning about DFT and trying to apply it to some audio processing. I am new to DSP but experienced in programming and have some background in math and physics. The FFT algorithm I use (lomontFFT)...
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### Why is the magnitude of the second component of my FFT spectrum always the largest one?

While working with FFT, I have a strange case with a current experimental setup. I am working with beat frequencies (intermediate frequency output) and using a standard FFT algorithm (complex to ...
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### change FFT bins position

I'm sampling a signal at 44100kHz, and I have 1024 samples on which I perform an FFT. My bin resolution is therefore around 43 hz/bin, so the frequencies I get energy for are multiples of 43hz: 43Hz,...
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### How to perform a time domain shift in the frequency domain without zero padding

Apologies in advance if my question doesn't make sense. I'm not the most fluent person in signal processing. I have an array of time domain values that I would like to apply a time delay to by ...
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### FIR Filter implementation without padding

Is it possible to implement FIR filtering action without padding the input and coefficients? i.e. Let's say if the input and filter coefficients are of size 4, then the output will be 7 samples. So, ...
I am very new to signal processing and want to learn the correct way of zero padding for 'n' even and odd input signals. For example, $N=6\;\&\;M=32$ \$x(n)=[a, b, c, d, e, f]\;\;\;n=0,1,\dots,N-...