All Questions

0
votes
0answers
2 views

How many ways are generally used for Image segmentation using Image processing?

I want to segment an image and extract very small specific area using image processing without using machine learning. Most of the time I used color based segmentation using thresholding. but it is ...
0
votes
1answer
3 views

The Gradient of 2D Image Convolution

Given the objective function: $$ \frac{1}{2} {\left\| h \ast x - y \right\|}_{2}^{2} $$ Where $ h $ is the 2D convolution kernel and $ x $ is the 2D convolution image and $ y $ is a given 2D image. ...
0
votes
0answers
8 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 ...
0
votes
0answers
6 views

Optical flow Horn & Schunck smoothness error

I was reading about the Horn & Schunck method and they define the smoothness error as (Robot Control 1988 (SYROCO'88): Selected Papers from the 2nd IFAC Symposium p. 348): $E_{sm} = \iint{\left(...
0
votes
0answers
3 views

What are i-vectors and x-vectors in the context of Speech Recognition?

I have read that i-vectors and x-vectors are widely used in speaker recognition tasks but I don't get the difference between them and how exactly they work. Can someone explain it starting from the ...
1
vote
0answers
7 views

Role of Riccati Equations in Kalman Filter Design

I am working on a Kalman Filter (KF) design problem and I am struggling to understand the role of the Riccati equations in the design process of a KF. Some sources discuss the importance of Riccati ...
0
votes
0answers
5 views

Papers/ guidance on the practicality of converting quantization steps (pixel) into phase adjustment (frequency) for CMOS images

In this older question How does subpixel image shifting using DFT really work? 2013, there is a clear answer which explains that the ability to sub-pixel shift (frequency domain) depends on the ...
0
votes
0answers
11 views

How to find out that a wav file is edited or original in Python?

I want to verify that if a audio (.wav or any format) file is original or edited. How can it possible in python? For example, for an investigation purpose I get a audio file for an evidence. I want ...
0
votes
0answers
15 views

Window function correction when using frequency domain likelihood

I was wondering if someone could tell me or point to resources which discuss what kind of of windowing corrections factors one should use when using a frequency domain Whittle likelihood for spectral ...
0
votes
0answers
13 views

Can we band pass filter QPSK signal?

Consider we have QPSK signal with carrier frequency 10kHz. Generally, we demodulate or use matched filter on the the QPSK signal and recover the transmitted bit or the symbols. If the QPSk signal is ...
0
votes
0answers
10 views

Early estimate the sign of the drift in a generalized Wiener process

I posting here my problem, perhaps somebody can point me how to proceed further :) [The challenge] I have an electronic system that can be modeled as a Wiener process with a drift $\mu$: $ X_t = \...
0
votes
1answer
20 views

Subtract audio to another audio

suppose I have a sample of a snare and that snare is used in a song,¿ there is an algorithm or tool that detects the sound of the snare and subtracts it, that is to say that cancels its phase or ...
0
votes
1answer
29 views

Notch filters: why is R(0) = R(π)?

I'm studying for the final exams and many example exercises require to design fir notch filters of length 5, given some passband and some stopband frequencies. You'...
-1
votes
0answers
14 views

What is definition of cross correlation function?

I mean there are three different formulas for cross correlation that I have studied f and g are two functions whose correlation has to be found 1.For Energy signals 2.For Power signals 3.For ...
-2
votes
0answers
22 views

How can I prove this properties of Auto correlation? [on hold]

Plz mention assumptions taken while prove separately. There are also few queries I have regarding this formula 1.I have read But shouldn't value of auto correlation at infinity be minimum , but ...
0
votes
0answers
13 views

Scalable/vectorizable way of thresholding a time series with a changing baseline value

I have a timeseries composed of many overlapping signals and a variable* baseline. My goal is to create a thresholded delineation of activity, essentially splitting between activity and baseline. The ...
0
votes
1answer
43 views

How to get Fourier coefficients to draw any shape using DFT?

I'm teaching myself about Fourier Series and the DFT and trying to draw a stylised $\pi$ symbol by fourier epicycles as detailed by Mathologer on youtube (from 18:39 onwards). The goal is to generate ...
0
votes
0answers
10 views

Not sure why I get errors of missing blocks when trying examples in Gnuradio Companion

I just started working with GNURadio without much of familiarity about this software. I found a couple examples online and I tried to run them but I get many Missing Block errors. Thats how it looks ...
0
votes
0answers
10 views

Differentiating high frequencies if a signal

I have a power signal (in dBm) which contains lots of peaks (around -80 dBm) and most of the time is around -110 dBm which we can call it noise level (obviously with fluctuations). As you know, both ...
0
votes
0answers
11 views

Worst-case error bounds for PLL

I am working on a project that involves time synchronization and we want to derive worst case bounds for the accuracy of the current time given measurements with known error as input. Unfortunately ...
0
votes
0answers
12 views

preamble for doppler shift estimation

To estimate the doppler shift in a multiuser communication, I use preambles (PN codes). When I send the preambles with the datas (BPSK symbol), the estimation for the doppler shift are not correct. ...
0
votes
0answers
32 views

Gaussian kernel notation

In this paper on content-aware seam carving, they have given an equation: $$ w^{s}(k)=\frac{1}{n^{k}} \sum_{i=1}^{N}\left[\mathcal{N}\left( \|z_{i}-o| |_{2} \; | \; 0, \sigma^{2}\right) \cdot \...
0
votes
1answer
27 views

FFT command line application?

Are there any command line programs for Windows, preferably free and stand-alone, which can report the peak/strongest frequency within a given range of frequencies? I need something like this to ...
1
vote
1answer
16 views

What impact have different types of border-handling on high pass or low pass filtering?

When high or low pass filters are being applied to an (grayscale) image, the borders need to be handled separately. They could be filled with 0's or 255's (b/w), repeat the nearest pixel value, or ...
0
votes
0answers
4 views

How would one reduce dimensionality/covariance in a dataset with nonlinearly covariant variables? Is M-SSA a no-go?

I am familiar with the Principal Component Analysis method of covariance and dimensionality reduction. I am considering using its multivariate time series brother, Multivariate Singular Spectrum ...
1
vote
1answer
21 views

Calculate the Standard Deviation of Fundamental Frequency (MFCC)

I'm implementing a gunshot detector following the article "Algorithm for Gunshot Detection Using Mel-Frequency Cepstrum Coefficients (MFCC)" (paywall). In the article, the authors uses 22 features ...
0
votes
0answers
7 views

How is n_pucch_2 in rrc layer computed

In LTE network I know that n_pucch_2 is used to indicate the resource index for pucch format 2/2a/2b. And I know its value is defined in higher layer. But how is the value computed and defined in the ...
1
vote
1answer
34 views

Fourier transforms and time shift

There is probably something trivial behind this, but I am missing something. I need to create a stationary random time series data v(t) which is the the sum of another time series u(t) and u(t) with a ...
0
votes
0answers
29 views

What is prewhitening filter mode?

In this paper, the following prewhitening filter is described: $$ C(z) = \sum_{k=0}^n c_{k}z^{-k} $$ where $n$ and $c_k$ are known. The paper also describes the values $C(\lambda_{k})$, with $\...
0
votes
0answers
40 views

Is a LTI filter completely characterized by its frequency response

I know that we use the frequency response to determine the properties gain and phase delay of a filter. However, I was wondering if this is enough for a complet characterization of the the filter for ...
0
votes
0answers
12 views

Tracking a signal

I have two signals representing steering wheel angles, one representing the driver’s inputs (red), while the other one represents the system’s reference signal (blue). I want to estimate in real time ...
0
votes
2answers
36 views

Nulling odd samples of the FFT of a signal

Given X is a N point time domain sequence, let F be the DFT of X. Let Z be a new sequence of length N formed by setting all odd samples to zero. The even samples of Z are equal to the even samples of ...
0
votes
0answers
16 views

Range estimation based on distance differences

It is a range estimation problem, as shown in the figure. The blue circles are the anchor node' positions, which are produced by one moving anchor (the moving direction is shown with black arrow). ...
0
votes
0answers
5 views

How to normalize data by mapping data points from one mixture of multivariate normal distributions to another

Problem description I am trying to normalize multivariate time series data. The individual data sets (spectrograms from temporal EEG) comes from sources that differ widely in their noise ...
0
votes
1answer
26 views

Time derivative of signal - effect on noise distribution

I have an angular velocity measurement that has a certain amount of ripple that yields an histogram shaped like a gaussian curve. I quantify that ripple using a standard deviation. I am interested in ...
0
votes
0answers
10 views

Looking for next-step ideas/ IMU data

I'm in a bit of rut regarding how to get anything useful from a data set i've created. Typically i have the following features, from a few different journeys on my bike: timestamp temp_h temp_p ...
0
votes
0answers
15 views

Why do I need this modulo tweak to bandpass filter an I/Q signal

I have an I/Q signal with $f_c=2.06\text{MHz}$ and $f_s=50\text{KHz}$. I am looking the first 256 samples of the signal, which is a NumPY array of complex numbers. If I do a spectrogram of this ...
0
votes
0answers
4 views

Why can ARSS not recreate audio from a spectrogram without sounding muffled?

Why do ARSS and all audio to spectrogram then back to audio program's create audio files that sound muffled? I know their is some physics and math with the short-time Fourier transform and etc. I ...
2
votes
1answer
17 views

Cross Correlation dimensions

I have been trying to do the cross correlation of two signals, and I am expecting the output to have the same dimensions as the two signals have. However what I am seeing is that the cross correlation ...
0
votes
0answers
15 views

Detecting changes in signal due to server delay

I'm currently working on an application that can be used to determine when a signal changes due to a server delay. Essentially, I have an API that is used to output data to a UI. However, for reasons ...
0
votes
0answers
7 views

Combine correlating input signals to generate multiple output signals

Choosing a descriptive title was quite hard, as I am not sure how to describe my problem accurately. I have a mechanical system fitted with several sensors (Strain Gauges and motion Sensors). There ...
0
votes
1answer
9 views

Understanding the concept of semi-blind receivers

In the book "Signals and Images: Advances and Results in Speech, Estimation, Compression... ", an overview of using tensor analysis in signal processing is given. On page 243 it is explained that an ...
-1
votes
0answers
18 views

SIne and Cosine Filter

Im new in programming. Someone who is skilled in mathematics has given me this formula, but I do not know how to use it. He told me this is the code of the program and you do not need anything else. ...
0
votes
0answers
7 views

Is the Channel Equalization corrects Carrier Frequency Offset (CFO) in signal?

As we know channel equalization is used for restoring the distortion ocured in signal. Hence, can we say the Carrier Frequency Offset (CFO) is being corrected and restored the actual signal.
0
votes
0answers
13 views

FMCW radar beat resolution with target spectral width, non-linearity and receiver resolution

The question is about resolution of FMCW radars whcich send triangular frequency waveform, receive it's echo then mix it with sent signal, extract beat frequency. The beat frequency is proportional to ...
0
votes
0answers
14 views

Find specific feature within an image / Neural Networks

i am working in the field of image processsing and we have a certain problem which is difficult to solve by rules-defined algorithms. Is it possible to teach a certain pattern into a neural network, ...
0
votes
0answers
14 views

Obtaining a sine wave ECG from a matrix of short arrays

I am a software developer, so please forgive my limited knowledge in the DSP space. I am given a task to plot an ECG graph and the data I receive from an ECG (BLE) device is provided in a matrix of ...
0
votes
1answer
25 views

Peak Detection on ECG signal

I've been working on a ECG signal collected during exercise through my chest mount heart rate monitor. My goal is to accurately detect the location of the R-wave; R-wave is the narrow peak similar to ...
0
votes
2answers
20 views

Using different algorithms/formulas to create spectrograms

On the internet, I have seen people use Matplotlib/Python and short-time fourier transformations to create spectrograms. Are their other formula/algorithms to create spectrograms? And are they ...
0
votes
0answers
14 views

Kalman filter with polar measurements: is the innovation a geometric difference of vectors?

I'm debugging someone else's implementation of a Kalman filter and it uses a cartesian state space and takes observations in polar coordinates. When looking at the mathematical description of the ...

15 30 50 per page