Signal Processing Stack Exchange
Signal Processing Stack Exchange

Questions tagged [noise]

In signal processing noise can be considered random unwanted data without meaning.

Noise is data that is not being used to transmit a signal, but is simply produced as an unwanted by-product of other activities. "Signal-to-noise ratio" is sometimes used to refer to the ratio of useful to irrelevant information in an exchange.

Source: Wikipedia.

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Determining the "whiteness" of noise

How does one quantify how "white" some noise is? Are there any statistical measures, or any other measures (FFTs for example) that can quantify how close to white noise a particular sample is?
Kitchi
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Where can we find noises like Gaussian, Rayleigh, Gamma, exponential noises in real world images?

I know that while taking pictures from a camera, noise may appear in the image. It is often described as Gaussian, but what about the other noises, when do they occur in real world? Please help!
Animesh Pandey
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What is the difference between 'de-noising' and what we commonly know as filtering methods to remove noise?

Pretty simple question - I am trying to figure out what exactly is different between 'de-noising' a signal, and simply filtering it (as we commonly know) to remove noise. Is this a case of lexical overlap or is there something fundamentally…
Spacey
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Zero Crossing of a Noisy Sine Wave

I'm trying to find the zero crossings of a sine wave to transform the sine wave into a square wave. The only problem is that the sine wave is noisy, so I'm getting lots of jitter and false zero crossings. Can anyone recommend any simple psuedocode…
Kevin Nasto
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limit to possible noise shaping?

I want to do noise shaping in a 100kHz, 16 bit application, so as to shift all quantization noise to the 25khz-50kHz band, with minimal noise in the DC-25kHz band. I set up mathematica to create a 31-sample error filter kernel via reinforcement…
tobalt
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why Gaussian noise is usually used?

Gaussian noise with different SNR levels are usually used in research works to simulate a realistic environment. How can researchers guarantee that Gaussian noise can simulate the reality of a System?
SAH
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How can noise be good?

It seems like (controlled) noise can sometimes be good: dithering in an image, or a softer sound in audio, or white noise alone. Here's a paper on noise improving detectability. My intuition also says that noise in a financial trading algorithm…
Toph
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PSK vs FSK for noise immunity?

Which method provides better noise immunity? I know you can transmit more data via psk, but what about which method is less susceptible to noise?
SamFisher83
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When modelling noise,how do they decide whether additive or multiplicative?

How does one take a decision of whether noise is additive or multiplicative?
Antenette
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What are the typical causes of clicks and pops in an audio file?

If a device generates clicks and pops at start and end of audio file playback, even when those audio files are completely zeroed out and dc-offset corrected, what could've caused them?
alphablender
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What is the difference between i.i.d noise and white noise?

I want to know the difference between independent and identically distributed (i.i.d) noise and white noise. In my short knowledge, i.i.d is that there is no relationship about time dependency. White noise means that there are relationship about…
gmotree
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Noise detection

I was wondering if someone could suggest a method to differenciate between two signals, on algorithmic scale for example a criterium to calculate, that shows how noisy a signal is, i have found a post about Signal-To-noise ratio but i am not sure…
Mehdi
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In signal averaging, will the noise be reduced if the noise is not Gaussian?

My understanding is that signal averaging works this way. If we take the average of the waveform, we get the average of the signal component (which is the magnitude of the signal) and the average of the noise component (which becomes closer to zero…
schrodingerscat11
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Additive noise meaning

What is additive noise? What actually additive means? I have tried to search in the internet but the only answer that I get is the noises gets added therefore it is additive, which make me think that noises are not destructive in nature am I right?
Suraj Kumar
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Is noise figure dependent on input noise power?

I was reading about Noise Figure on Wikipedia (https://en.wikipedia.org/wiki/Noise_figure). There, I saw the following definition: The noise factor is thus the ratio of actual output noise to that which would remain if the device itself did not…
Mostafa Ayaz
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