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

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1answer
26 views

Active noise cancellation using kalman filter

I am doing signal processing on audio data sampled at 8Ksps in matlab but it is corrupted with random noise. Therefore, I decided to use LMS and RLS ANC algorithms to remove overlapped frequency ...
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2answers
39 views

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 ...
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1answer
19 views

Decorrelating Stationary Colored Gaussian Noise — Effect On The Desired Signal

So given stationary colored gaussian noise $\mathbf{n}$, I know that I can decorrelate it by first finding it's autocorrelation $R_{nn}$ and performing $R^{-\frac{1}{2}}_{nn} \mathbf{n}$. In ...
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62 views

Additive Gaussian white noise - bandwidth

The average power at output when additive Gaussian white noise is present is given by the formula below: $$P_0 = \int\limits_{-B}^{B} \frac N2\ df ,\quad \text{with $B$ being the bandwidth.}$$ My ...
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1answer
26 views

SNR and noise in Simulations

I've always taken the definition of noise and SNR for granted in doing BER simulations in an AWGN channel. I would usually use the AWGN noise function and make a loop with varying SNR values. ...
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1answer
28 views

Concept question - What is noise?

I've been studying image processing methods (without signal processing background) and many things are interesting to me. I was think about noise. In many definitions noise is unwanted and without ...
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1answer
26 views

What is the value of the standard deviation $\sigma$? [closed]

I am using the following formula to add the additive Gaussian noise. noise= (x/255)*(randn(size(image))), where x is the ...
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2answers
37 views

generating white gaussian noise in matlab using two different functions

I want to know the difference between the two Gaussian noises generated below? Which one is white and how can i make the other one white? y=wgn(1,10000,0) and ...
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1answer
23 views

Image averaging for impulse noise

I understand the mathematics behind the use of image averaging for gaussian noise. Why can't it be used for impulse noise ? Would it be because there is no way to prove that impulse noise is additive ...
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69 views

Segmentation of small artifacts - Image Processing

I am working on a task of segmenting small artifacts from a set of images like below: I am looking for a generic approach, but unsure of what to search? I tried looking at density flow analysis, but ...
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0answers
44 views

Resources on Non-Gaussian Channels

I understand why most of the classic textbooks only consider Additive White Gaussian Noise channels in digital data transmission. Unfortunately in my case noise is not Gaussian and it might even be ...
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2answers
52 views

What is the difference between a'mixer' and a ' multiplier' used in modulation process?

I am not sure if it is valid to conclude that a mixer produces a difference/sum of frequencies at output ,while multiplier produces multiples of frequency at its output. I am keen to know how far I ...
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1answer
22 views

Sox, mixing mono inputs into mono output (efficiently)

I want to mix two mono files, signal.wav and noise.wav, into a single mono file, signal_noise_mono.wav. Currently, I know how to mix the two input files into a stereo file and then remix it to mono, ...
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0answers
18 views

Should S-Matrix components for scattering response in a Polarimetric Radar be Real or Complex?

I am trying to implement some polarimetric decomposition algorithms on my MIMO polarimetric radar. At first, I will try the Pauli Decomposition algo. But instead of doing signal processing on the ...
3
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1answer
52 views

Filter for noisy accelerometer data

I tried to read up and get a filter for a 3-axis accelerometer but this is more confusing than I thought. I have an IMU with a 3-axis accelerometer on the end of a robot link which is rotated around ...
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1answer
49 views

Calculation of an autocorrelation function

A sample of a random process is given as: $$ x(t) = A\cos(2\pi f_0t) + Bw(t) $$ where $w(t)$ is a white noise process with $0$ mean and a power spectral density of $\frac{N_0}{2}$, and $f_0$, $A$ ...
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1answer
63 views

Audio Broadband Noise Detection

I have to quantify the broadband noise of an audio track. I've seen lots of things around and the only viable option to estimate the broadband noise (without having any information about it) is ...
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1answer
43 views

Looking for low-noise audio data to benchmark some noise-processing techniques

I'm looking for a source of very low-noise audio data for use in benchmarking various methods of random noise correction methods. My intention is to have a very clean signal to which I can add known ...
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4answers
74 views

Finding the Amplitude of a Sinusoid in Noise

I'm trying to solve for the amplitude and frequency of a sinusoid embedded in zero-mean gaussian white noise. I am supplied a sample file of a 40000 element array. I first took the autocorrelation ...
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26 views

Noise Robust Linear Prediction

So it appears that Linear Prediction as performed via Durbin Recursion is sensitive to additive noise. What are some techniques for linear prediction that may be more robust? Can anyone supply a link ...
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2answers
129 views

Fourier transform of a Fourier transform

I generate a Gaussian noise and then I filter it with a passband FIR Kaiser window filter. When I perform the Fourier transform of the output of the filter and plot its magnitude spectrum, it is ...
4
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1answer
53 views

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 ...
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0answers
68 views

1/f noise parameter characterization

I would like to characterize 1/f noise in some time series data. I would like to estimate the 1/f noise corner, and the standard deviation of the 1/f noise component and white noise component. The ...
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0answers
17 views

Generating 3-dimension $1/f^\alpha$ noise

I'm stumped trying to find a way to generate a 3-dimensional $1/f^\alpha$ noise time series. Basically I want simulate a forcing that is $1/f^\alpha$ in the 2 space dimensions and $1/f^\beta$ in time, ...
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0answers
35 views

Adding two audio files at a predefined SNR level

I have two speech audio wav files. file1 is primary speech, file2 is supposed to be interference. I want to add them so that ...
3
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2answers
69 views

Adding “realistic” noise to signals of different amplitudes

I have a question regarding basic signal processing, which I have to start using since I have started studying fault isolation. The thing is, I have three computed signals, which are gathered in the ...
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0answers
28 views

Approximation of Step Response from Data with delay

How can I approximate a Step Response curve from a measured data of a single input and a single output using Matlab while the delay between the input and the output is 30 minutes?
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1answer
29 views

How to measure noise, consonance, dissonance of a sound?

How can I make a graph of the noisiness of some audio durations of 100ms - 10s with 100% being white noise and 0% being a sine wave. I have FFT at the moment, are there other ways to know the ...
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3answers
80 views

Determine whether a signal is increasing or decreasing over time

I have a signal (x-axis: Time, y-axis: Data) which has more than 10000 samples per second. The signal itself represents some physical data (e.g. speed, acceleration, etc.) and has some noise on it. ...
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2answers
36 views

What does it mean by “Adding Gaussian Noise to a 2D Image”? [duplicate]

As far as I understand, Suppose, we have a 2D image of pixel resolution 200 x 300. That means, the image has 60000 pixels in it. Now, we would generate $n$ random values and add those values to $n$ ...
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2answers
658 views

Why is Gaussian noise called so?

Can you please explain: why is a specific type of noise called "Gaussian noise"? Why is it relevant to call it Gaussian? Please, explain in layman's terms.
3
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1answer
61 views

What would produce this “hamburger” corruption on images?

I have an image that has gone through an unknown number of jpeg and webp conversions (at least one but more likely 2+). Currently this image is a JPEG and contains corruptions in single color or mild ...
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0answers
47 views

How to know if there is noise affecting my signal

I have a signal shown in the attached figure and the fft of that signal as well. In addition I have also attached the fft of the static noise signal. You can see that in the original signal there are ...
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2answers
100 views

Detecting outliers/noise from sensor data

I am trying to detect outliers/noise as indicated on the diagram below from sensor data. Can anyone advice how to go about it? I can only do this in python, so are there libraries in python that I can ...
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0answers
18 views

Which are the known techniques to filter noise from time series?

this is not a specific question. I would like to know the known techniques to filter noise or make a noise reduction, in specific, from time series, but can be other type of data with wave format and ...
0
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1answer
57 views

Double Integrating Gaussian Noise

My question has to do with integrating gaussian noise. Let us assume we have samples of discrete gaussian white noise with mean $\mu = 0$ and variance $\sigma_{th}^2$. These noise samples are passed ...
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2answers
74 views

Numerically generating noise time series from spectral density

I'm trying to figure out a way to construct (numerically) time series of random variables given some spectral density $S_{xx}(f)$. I'm interested in various types of spectral densities (flat, ...
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0answers
33 views

Periodic noise attenuation

I have continuous data with very high amplitude periodic noise. Data is sampled at 500 Hz. The period of the noise does change with time but within a short interval (~ a minute) it is constant. Top ...
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14 views

approach to differentiate noisy data with steep ramp

I'm trying to write some image processing code in python to differentiate between two types of images (we'll call them set Blue and set Amber). I have run an algorithm I wrote that results in the ...
4
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2answers
146 views

Convert sine wave signal to square wave signal

I have a signal containing a variation of digital ASK type on-off keyed sine wave among which some stochastic irrelevant harmonic waves occur, like you can see on this figure: In its current form ...
3
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1answer
67 views

Fourier transform of Image to identify sinusoidal sources of interference

I'm a statistics grad student, and I just started getting into Digital-Image-Processing (an analogy for processing super-large contingency tables). In the book "Digital Image Processing" by Gonzalez ...
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1answer
126 views

Matlab signal processing removing white noise from signal

What is the way to address the removal of white noise from a signal? Extra Details Hi I also agree the details are as follow: ...
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2answers
30 views

white noise in images

For digital images, noise is assumed to be additive gaussian white noise. I remember noise in images is considered as high frequency. However, from the link https://en.wikipedia.org/wiki/White_noise, ...
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1answer
66 views

what's gaussian noise look like?

I am using Matlab function imnoise to add gaussian noise to one image. However, it seems that adjacent samples of the noise is correlated. I am using matlab code below to add noise. ...
0
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0answers
17 views

How one can perform a noise free first order derivation in discrete domain?

I need to have a noise-free first order derivation. Now I am using a simple (x(n)-x(n-1))/Ts. It is super-sensitive to noises. Do we have a noise-free or noise-reduced first order differentiation ...
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0answers
14 views

Predict the maximum power of a signal in the presence of noise

My question relates to predicting the power of a signal in the presence of noise. The signals I am analysing are discrete quasi-periodic signals (jittered sine waves basically). If I do a spectral ...
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2answers
49 views

How can I duplicate this type of image?

I'm very new to the idea of signal processing, could someone point me in the direction of of a program to toy with images, below is a link to 2 taken a split second apart that showed up on my Amazon ...
0
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1answer
21 views

What does pre-emphasis $\alpha=1$ will do to a signal?

I am trying to understand pre-emphasis equation. $$ y[n]=x[n]-\alpha x[n-1]$$ Where $\alpha = 0.95$. My question is what does it mean if $\alpha = 1$?
0
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1answer
18 views

What is the difference between photon shot noise and salt and pepper noise?

I am currently working on an application which deals with the restoration of fluorescent beads examined using widefield microscopy. There are two major sources of noises that are being encountered in ...
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6 views

Valid non stationary non parametric white noise tests for non strick stationary time series

I could not find a question where testing for white noise for non strick stationary non parametric time series is adressed. Traditionally testing for white noise is done via multiple tests for the ...