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What are $H(i\omega)$, $H(s)$ and $H(z)$ called?

What are the Fourier-, Laplace- and Z-transforms of the impulse response of a filter called? I've seen $H(s)$ referred to as the system function or transfer function, what about $H(i\omega)$ and the discretized $H(z)$?
Andreas
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Is real-time signal processing possible under Windows?

This question is related to on How to decide what platform is best to implement real-time audio processing on?, but focusing on Windows. I'd like to be able to take input from a data acquisition board and process it (either through Matlab or a…
jonsca
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How do I reconstruct a covered-over part of a regular pattern

I have a set of images which consist of a fairly regular pattern - essentially a set of roughly concentric distorted ellipses - with a small area (<1% of the total image area) obscured by a circular disk. I'd like to be able, digitally, to…
Eos Pengwern
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Matrix form of 2D-DFT for a vectorized image

I want to apply 2d DFT to a N by N image. However, image is vectorized such that it is NxN by 1. How can i find the matrix form of 2d DFT such that resulting vector from multiplication is the vectorized NxN by 1 2d DFT of my N by N image?
strahd
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How to Zero Pad in Order to Perform Filtering in the Fourier (Frequency) 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 $f$ with $h$ (that is, we can filter image $f$…
user40095
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For complex values, why use complex conjugate in convolution?

Taken from Adaptive Filter Theory (2014) written by Haykin page 110 : $$y(n) = \sum_{k=0}^{\infty} w_k^*u(n-k), \quad n=0,1,2,...$$ where $u$ and $w$ are complex values. My question is why use complex conjugate of $w_k$? The answer found in the book…
Ηλεκτρολόγος Μηχανικός
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Deconvolution of Synthetic 1D Signals - How To?

I convolved a square wave with a Gaussian wave using linear convolution. Can I get the original square wave back by deconvolving my output with the Gaussian function? I took the FFT of both signals, divided and then took the IFFT to get back the…
Anand Mohan
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PSD of complex white gaussian noise

It may be a really simple question, but I'm not sure about this one: Given a complex white Gaussian noise process with iid real and imaginary parts and a double sided power spectral density of $N_0/2$. What is the PSD of this random process? Is it…
Phobos
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Is sound the best way to transmit a signal under water?

Could sound be used in transmitting sound waves under water digitally? Could the sound then be converted by a repeater to transit by radio waves? What other ways can a signal be transmitted other than sound over long distances under water?…
Muze
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Intuition behind commutativity of convolution in LTI systems

Why is convolution commutative, as it seems to treat two signals in a different way in an LTI system? If you imagine $y[n] = x[n] \star h[n]$ with $x[n]$ being an input signal and $h[n]$ being the impulse response of an LTI system A, how does it…
NightRain23
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Removing noisy lines from image - opencv - python

I want to process different type of image to extract actual text from noisy image .I am using open cv to do this job it is working fine but the problem is I need to set different lower threshold to convert noisy image to readable text.Is it…
Jeya Kumar
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Calculating the SNR of Audio Signal (Recommended Libraries)

Are there any open source packages or libraries available which can be useful in calculating the SNR(signal to noise ratio) of an audio signal. The input will be just an audio signal and I have to calculate the SNR of that signal. Can anyone suggest…
shresth
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Contour and area, raw (spatial) and central image moments

I recently started using image moments for image processing of binary images. I read that the $0^{th}$ order contour moment is the perimeter and the $0^{th}$ order area moment is the area. These raw moments are both given by: $M_{ij} =…
Olivier_s_j
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Understanding FFT: FFT size and bins

I'm trying to implement an FFT to understand how it works. I'm using a random sound file (so I can't control the size of the signal), with a sampling frequency of 44,1Khz. I'm using this library: Fft.java The objective is to apply this formula to…
Bouji
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How is it possible to Filter out a person's voice out of 100 of other voices?

So, I've just learned that the human voice is not a single sine wave its a bunch of unlimited Sine waves each having a different frequencies, According to Wikipedia, The voice consists of sound made by a human being using the vocal folds for…
Sufiyan Ghori
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