# 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.

44 questions
Filter by
Sorted by
Tagged with
25 views

### FastICA: what happens when we have more source than channel?

I am reading the original article proposing FastICA and I have a couple of question on point not covered in the article. Both answering me or providing a source will be very appreciated. I want to ...
16 views

### ICA School Project

I have been stuck on my school project that consists of independent component analysis. My code will run, but only 50-60% of the time it unmixes the signals. Another problem I have is the amplitudes ...
15 views

### What ICA should be applied?

I am using ICA from EEGLAB toolbox (not sure if I can use MATLAB's RICA() function as well). I am trying to use Infomax or JADER ICA to seperate two sources which transmitting at a carrier froquency ...
55 views

### What Is Meant by Clustering of ICA (Independent Component Analysis) Components?

I'm following the EEGLAB tutorial about STUDY creation and manipulation of the datasets, and came across the concept of clustering of ICA components. I'm not too familiar with processing of ICA ...
121 views

### Down sampling an EEG signal

I have a set of 10 minute EEG signals that were sampled at 400 Hz and have 16 channels which corresponds to a 16x240000 matrix. These EEG signals belong to two different classes. I am trying to ...
31 views

### (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 ...
41 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}\...
1k 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, ...
743 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 ...
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 ...
40 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 ...
126 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 ...
319 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 ...
56 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 ...
140 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 ...
2k 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 ...
513 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 ...
371 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 $k$ ...
753 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 ...
3k 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 ...
814 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 ...
360 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: ...
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 ...
306 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 ...
41 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 ...
106 views

### Separate static echos from acoustic signal (ICA?)

I am using acoustic waves to measure the thickness of material. My problem is that the acoustical lens produces static echos in the signal. I try to separate both because there is a short interference ...
48 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 ...
1k 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 ...
225 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 ...
148 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 ...
56 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 ...
383 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....
723 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 (...
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 ...
450 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. ...
349 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 ...
2k views

### How to remove reflections from images?

I've been playing around with making images better and removing all the unwanted disturbances from it. I found out a major concern would be removing the unwanted reflections that might come. I've ...
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 ...
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 ...
1k 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 ...
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 ...
405 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 ...