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Questions tagged [ica]

Independent Component Analysis is a computational method for separating a multivariate signal into additive subcomponents supposing the mutual statistical independence of the non-Gaussian source signals.

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(For c-FastICA) On covariance and pseudocovariance matrix of a complex random vector

I am currently studying complex FastICA and the paper says that Suppose $\mathbf{s}$ is a $n\times1$ complex random vector. If $\mathbf{s}$ has zero mean, unit variance, and uncorrelated real and ...
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34 views

Clarifying matrix notation from an ICA-CMN paper

In the paper I am referring (and here from citeseer), complex vectors $\mathbf{z}$ and matrix $\mathbf{M}$ were defined as follows \begin{align} {{\bf z}} &= \left[z_{1},z_{2},\ldots,z_{N}\...
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502 views

Cocktail Party Problem — audio source separation

I am trying to solve the Cocktail Party Problem. I am trying to separate these two mixed audio files: mixed 1 [WAV] mixed 2 [WAV] into 2 separate audio files that contain the 2 original sources, ...
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33 views

Why is ICA whitening code not giving results?

i am trying to implement FAst ICA for my project, but i am facing it hard to just go through the fisrt step. The code that i am using in matlab is as given below for ex ...
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2answers
504 views

Camera measurement of heart rate - frequency bias towards 50 bpm (0.83 Hz)?

I am trying to develop a RGB camera-based non-contact measurement of heart rate using principles of remote photoplethysmography. I want to be able to measure a range of heart rates I have been looking ...
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32 views

Sourse separation from known underdetermined mixing matrix

How to recover uncorrelated N sources from given N-1 signals and known mixing matrix M, (e.g. 9x8 matrix)? If I just use pseudo-inverse matrix M+, my source estimates are correlated with each other ...
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37 views

What ICA approach is best-suited for semi-blind convolved source separation?

I have a mixed discrete signal $$ A(t_i) = [s(t_i) + a f(t_i+\delta)] \circ g(t_i) $$ for n number of temporal points where $s(t_i)$, $a$, $\delta$ are unknown. $\circ g(t)$ is a convolution, where ...
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115 views

ICA for blind source separation clarification question

I'm currently trying to implement FastICA for blind source separation from scratch. The code below does not generate W, the umixing matrix, correctly. When I matrix multiplied the outputs ...
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252 views

Is This Interpretation of Auxiliary Independent Vector Analysis (AuxIVA) Correct?

I am implementing auxiliary function based Independent Vector Analysis (AuxIVA) from Nobutaka Ono's original paper Stable and fast update rules for independent vector analysis based on auxiliary ...
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49 views

The effect of the mixed signals probability distribution on the ICA performance

Does the mixed signals distribution affect the ICA performance? I mean the ability of ICA to get the sources. Assume that the mixed signals follows a Gaussian distribution and of course the sources ...
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115 views

EOG artifacts turn up in several ICA source signals

I try to remove EOG artifacts from my EEG signals (I am using a EPOC+ for recording and MNE Python for processing). Therefore I've recorded test data with blinks every 5 seconds. The blinks can be ...
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1k views

How is the topo / scalp map from an EEG Signal with ICA created?

I am lately experimenting with an EEG and found this Library: MNE Python. I am using an ICA to find and correct artifacts - this is working fine. It's now possible to plot a topo / scalp map for the ...
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433 views

How to implement Fast ICA on multiple wav files?

I am doing an exercise wherein I have three wav files which comes from recordings from three microphones on an event. I need to implement Fast ICA to decompose the original signals using the three wav ...
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1answer
331 views

Blind source separation on images - with a known source

A camera outputs an image $A$ that is a linear combination of two uncorrelated images $B$ and $C$: $$A = B + kC$$ Images $A$ and $C$ are known; the unknowns here are $B$ and a scalar coefficient $k$ ...
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682 views

How to remove a common noise signal from a set of signals?

I have 2D measurement results which seem to have a constant non-trivial background as shown here: For every column in this image, there seems to be a similar oscillation. I'd like to distinguish this ...
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2answers
2k views

Why non gaussian variables are independent

I have read a lot about ICA. I think I could not find the answer that why non-Gaussian Variables are independent. What I understand, Central Limit Theorem states that distribution of sum of ...
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1answer
677 views

Removing DC offset and ensuring zero-sum for 2D filter

I'm working on project where I'm using Independent Components Analysis (ICA) on NxN patches from images to separate components in an image signal. Each column of the resulting MxN^2 unmixing matrix is ...
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1answer
317 views

ICA - Exercise Problem from book - Matlab Code

Im trying to do a problem of ICA from a Image Processing book, but when I finish I got the Matrix C different from the one in the exercise. This is the Exercise: This is my Matlab Code: ...
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4answers
2k views

FastICA - Purpose of centering and whitening the Data

I'm learning about ICA, but dont know whats the purpose of centering the data (making each component have zero mean)and whitening the data (not sure what is this for, is it the same as PCA?), I'm ...
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1answer
265 views

FASTICA algoritm produce independent components does not equal to the dimensionality of EEG signals

From my knowledge about independent component analysis the number of channel or variables will not be affected by this algorithm and the number of independent components will be equal to number of ...
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1answer
38 views

Extract a square-shaped signal which lies in a specific range

I need to extract (estimate) a square-shaped signal from the main signal. This square-shaped signal should be located within a specific range, in fact all we have to do is to estimate its height. A ...
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2answers
91 views

separate static echos from acoustic signal (ICA?)

Iam using acoustic waves to measure the thickness of material. My problem is that the acoustical lense produces static echos in the signal. I try to seperate both because there is a short interference ...
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1answer
47 views

How to decode speaker gender from spoken transcript

I have 20 audio recordings (raw format) of people reciting the same ~50 word transcript. I would like to use audio signal analysis to decode speaker gender from audio recording. Intuitively, it ...
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2answers
982 views

Using ICA on EEG signals for feature extraction

I am attempting to use ICA (FastICA via scikit-learn) on EEG signals from seven electrodes per subject for feature extraction and identity classification – that is to extract signal which is related ...
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2answers
216 views

Decompose stereo signal

Basically the same as this question, but it was never really answered: Stereo sound separation into three sources Imagine I have a really trivial signal: Left: 100Hz tone + 200Hz tone + 500Hz tone ...
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137 views

Can ICA be applied to solve BSS problem in frequency domain?

I'm recently doing research on EMI, and I want to seperate the mixing signals. However, the data given is in frequency domain. As I have used ICA to solve blind source separation problem in time ...
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1answer
54 views

Image blind separation

I am working in image cryptography using an ICA algorithm like JADE. To evaluate my work, I am used the SDR and PSNR. I would like to know what the acceptable values of the SDR and PSNR in image ...
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4answers
370 views

Which sections to cover for my graduation thesis on blind source separation?

I'm not sure if I'm on right place to ask a simple suggestion, so please be kind and don't downvote my question. I'm not asking someone to do it for me, I just need short guidance how should I proceed....
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1answer
707 views

Independent Subspace Analysis and Topographic ICA

Can anyone recommend the best references for independent subspace analysis (ISA). I have read 'Multidimensional Independent Component Analysis' by Cardoso and would like to know of any modern, solid (...
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2answers
2k views

Is there a way to reduce the covariance matrix of several source signals to the dominant source signal?

The problem I have can be seen in the context of DoA estimation or blind source signal separation and similar fields, where several source signals are observed by several antennas (or by an antenna ...
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2answers
446 views

Face recognition using independent component analysis (ICA)

Reading about independent component analysis (ICA), I learned that one of its applications is face recognition. I think in this problem we have a database of images and a test image to be recognized. ...
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2answers
336 views

Can I use independent component analysis if I have two discrete populations of signal sources mixed together?

I understand (mostly) how independent component analysis (ICA) works on a set of signals from one population, but I am failing to make it work if my observations (X matrix) includes signals from two ...
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1answer
2k views

How to remove reflections from images?

I have been playing around with making images better and removing all the unwanted disturbances from it then again i found out a major concern would be removing the unwanted reflections that might ...
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1answer
5k views

How can I calculate the Expectation for a particular known vector?

Let us say I have a row vector $X = [x_1, x_2, x_3, \ldots, x_n]$ and another row vector $Y = [y_1, y_2, y_3, \ldots, y_n]$. I want to check whether the two vectors are statistically independent or ...
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4answers
5k views

ICA - Statistical Independence & Eigenvalues of Covariance Matrix

I am currently creating different signals using Matlab, mixing them by multiplying them by a mixing matrix A, and then trying to get back the original signals using FastICA. So far, the recovered ...
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1answer
901 views

How does ICA handle inevitable delays in signals?

I am currently reading up on and teaching myself ICA from a number of good sources. (Also see this post for past context). I have the basic jist down, but there is something I am not clear about. For ...
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3answers
4k views

Fail to separate sound signals by FastICA on real-world recording

I have written a program to perform FastICA on a stereo WAV file using the code on Python MDP FastICA Example With the audio examples I get very good results. Then I try to do real world recording ...
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3answers
380 views

Is ICA appropriate for separating mixed signals when all source signals are NOT detectable at all sensors?

A generic implementation of ICA for the separation of a mixture of $N$ signals into their $M$ constituent components requires that the signals be assumed to be a linear instantaneous mixture of the ...
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3answers
952 views

Can ICA be applied, when the number of mixture signal is less than number of source signal?

I am referring to the the following paper : Non-contact, automated cardiac pulse measurements using video imaging and blind source separation In the above article, the authors are able to extract ...
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1answer
4k views

What are the proper pre-processing steps to perform Independent Component Analysis?

What are the proper steps for preprocessing my waveforms in order to perform an independent component analysis (ICA) later? I understand the how, though further explanation of that doesn't hurt, but I'...