# Questions tagged [cross-correlation]

The tag has no usage guidance.

302 questions
Filter by
Sorted by
Tagged with
65 views

### Deriving the Langrangian interpolation polynomials in Cook-Toom convolutions

I'm working through Blahut's 'Fast Algorithms for Signal Processing'. Trying to develop an intuition for the Cook-Toom algorithm for convolutions as used by Lavin and Gray in their Winograd paper for ...
70 views

### Reduce noise of sensor by combining two

I've had the basics of signal in university but little real-life practice. I've got an acceleration sensor with a digital output signal (signed 16 bit value). This signal is a little noisy. The ...
84 views

### Cross correlation to compute delay between two lines does not work

I have zero experience with signal processing, and I am stuck in what I believe to be a very simple problem. I am trying to use the xcorr in matlab to find delay between two signals. The signals are ...
19 views

### Pearson correlation coefficient vs mutual information

I recently computed both the pearson coefficient and the mutual information of two time series as well as the corresponding error bars, and what I find out in the end is a significant level of ...
96k views

### How do I implement cross-correlation to prove two audio files are similar?

I have to do cross correlation of two audio file to prove they are similar. I have taken the FFT of the two audio files and have their power spectrum values in separate arrays. How should I proceed ...
102 views

119 views

### Faster Algorithm to convolve/correlate two sparse 1-D signals in python (or any language)

I have two signals which I need to correlate or convolve. Each signal is sampled non-uniformly and the values of the signal I have with me are the timestamp and the magnitude of the signal at that ...
22 views

### Wrong estimate of lag by xcorr between a signal and its segmented identical copy in Matlab

In general I have a series of signals that each following is a bit stretched version of the previous. To find the incremental stretching, I crop the original signal into some number of short segments ...
15 views

### match a pattern in a stream of bits

I feel my question is somewhat related to this, but I'm not sure how to do what I want. I get transmissions of ~1000 bits at a time, which may be corrupted by noise. To try and infer data from ...
8 views

### Obtain points in signals which cause correlation

I've got two large .wav files (tens or hundreds of minutes each). I know that at some points these files contain very similar areas - actually, these areas are the ...
110 views

### Group delay using cross correlation?

An input signal + (thermal) noise travels through a channel and can be measured at its output. Is it possible to use cross correlation between input and output signal to measure group delay? If not, ...
627 views

### Normalized cross-correlation in frequency domain

I never worked with signal processing and never really used Fourier transforms before, still I am working on a project consisting on taking the output of an accelerometer to detect some movement ...
53 views

### Finding recorded sub-signal in the original audio signal

I have the original record of a song, and some fragment of the same song recorded by a microphone. I need to find the time where the fragment is appearing in the original. I have tried to use cross-...
80 views

### How to group similar patterns together that are shifted along the x axis?

I have a set of time series plots that are shifted along the x-axis. I am looking for an algorithm using which I can group them together. My end goal is to average them. While reviewing the ...
126 views

### Correlation of independent random processes

Suppose $X(t)$ and $Y(t)$ be two independent random processes. Is $E(X(t_1)Y(t_2))$ necessarily zero?
25 views

### cpsd calculation help

I have several channels from where I am reading sensor signals in time domain. I have 9 channels where I am reading time domain signals from each and every channel for 10 seconds. Now if I perform ...
249 views

### Maximum cross-correlation coefficient value for time delay estimation

I am using cross-correlation for time delay estimation of two synchronized recordings ($x_1$ and $x_2$) of a fixed sound source from two different locations. I understand that the delay is associated ...
744 views

### Least Squares and Auto and Cross Correlation

I am trying to understand why auto and cross correlation helps find the best fit line in least squares. I have an equation as stated here: $Ax=b$ -- I have not exact solution, so I use the least ...
313 views

### Direct Correlation (DC) Time Delay Estimation: Variance Keeps Decreasing for Increasing SNR?

I'm trying to reproduce the results from this paper "Discrete time techniques for Time Delay Estimation" doi:10.1109/78.193195, for both the correlation and Least Squares. I've generated a random (...
3k views

### Convolution and Cross Correlation on 2D Image

I have read that convolution and cross-correlation are the same thing, but convolution flips 180 degrees (images), or time reverses (sequences) the kernel, before performing the elementwise ...
181 views

### Cross Correlation as Noise Reduction, is this possible?

If I have two sensor measuring the same signal but from two different locations from the source, and I get two different readings of the signal, each with slightly different noise. Is there a way to ...