How to Zero Pad in Order to Perform Filtering in the Fourier (Frequency) Domain?

1. What does zero padding do to Fourier transform?
2. What is the effect of zero padding in frequency domain?
3. How do you zero a padding?
4. Why zero padding is done prior to filtering?

What does zero padding do to Fourier transform?

Zero-padding a Fast Fourier Transform (FFT) can increase the resolution of the frequency domain results (see FFT Zero Padding). This is useful when you are looking to determine something like a dominant frequency over a narrow band with limited data.

What is the effect of zero padding in frequency domain?

In this case, we can say “zero padding in the frequency domain results in an increased sampling rate in the time domain”.

How do you zero a padding?

In zero padding, you add zeros to the end of the input sequence so that the total number of samples is equal to the next higher power of two. For example, if you have 10 samples of a signal, you can add six zeros to make the total number of samples equal to 16, or 32, which is a power of two.

Why zero padding is done prior to filtering?

Zero-padding allows space for this wrap-around to occur without contaminating actual output pixels.