Questions tagged [python]

Python is a high-level interpreted general programming language. Python has popular numerical and scientific libraries/packages, most notably numpy and scipy. The scipy.signal package is a powerful signal processing software collection. This tag covers the use of numpy, scipy, and other Python packages often used for SP computations.

Filter by
Sorted by
Tagged with
0
votes
0answers
31 views

Synchronization of tx and rx in sdr

I am implementing a FMCW radar using bladerf sdr: When reading the output from the vector sinks, the outputs are not synchronised.How should I synchronise them? is it possible to do so using gnuradio ...
1
vote
1answer
35 views

Faded line in spectrogram for a chirp

I've generated this spectrogram using wavelet convolution. The chirp is generated like so: ...
0
votes
0answers
7 views

Python Librosa Spectogram resolution is too low [closed]

I was following a guide about spectograms and for some reason when I try doing the spectorgrams by myself the come out rather blury, any idea what I am doing wrong? ...
0
votes
0answers
27 views

Python equivalent code for Matlab bandpass function

I have used a bandpass filter function in Matlab as follows ...
0
votes
1answer
16 views

Plotting a Time Frequency contour/colormesh plot of a Discrete Wavelet Transform

I have a pressure vs time data of a noise on which I wish to perform discrete wavelet transform. I have divided my frequency range into 1/3rd Octave Bands and have calculated sound pressure level at ...
1
vote
0answers
15 views

Is my implementation of Generlized Pencil-of-Function correct?

I have a time-series data that should be of the form $$ f(t) = \sum_nA_n(e^{\alpha_n t}+e^{-\alpha_n(T-t)});\;\alpha_n=\eta_n+i\omega_n;\;i=\sqrt{-1} $$ and I want to find parameters $A_n$, $\eta_n$, ...
3
votes
1answer
52 views

Understanding Parseval's Theorem with Discrete Wavelet Transform

I have difficulty to understand the results I get with implementing Parseval's Theorem in Python to DWT. I have the good results getting the Energy with Fourier transform and the time series in python:...
0
votes
0answers
52 views

Filter a negative SNR signal whose frequency spectrum lies inside the noise frequency spectrum

I am a newbie in Signal Processing and need your suggestion in the following problem. My signal amplitude is 10 times weaker than the noise. Furthermore, the frequency spectrum of the noise and the ...
3
votes
1answer
118 views

A-weighted Digital Filter for 1/3rd Octave Band Analysis

I want to do a 1/3rd Octave band analysis on a noise signal. But the sound pressure levels should be in dB(A), i.e., and it should be A-weighted. For this, I am using the A-weight function from this ...
0
votes
0answers
32 views

How to correctly pass filter states from one processing block to the next

I'm processing a 4 channel audio signal and due to memory requirements need to process the signal in an arbritrary number of blocks. To ensure consistent filtering between blocks I've been told I need ...
0
votes
0answers
97 views

Using FFT for implementing a filter bank

I am trying to use Fast Fourier Transform (FFT) for decomposing an audio signal into 8 sub-bands according to this link but the problem is the frequency response of the result contains only the first ...
0
votes
1answer
32 views

Receiver function, frecuency domain deconvolution not giving logic results

I'm working on some code for receiver function method in seismology. For anyone one not into the topic, it's just a deconvolution of two time series (seismograms). This can be done in the time domain ...
1
vote
2answers
49 views

Decimation Question about using a low pass filter before downsampling

I have a bunch of audio files that have a sample rate of 380kHz, however I would like to reduce this sampling rate to 44.1kHz. From doing some research online, it seems like I will have to use a low ...
0
votes
1answer
41 views

Mulitplication in Frequency Domain as a Similarity Measure of Audio Clips

I have an audio clip and I copy a 256-point part satarting at 10th second. Then I create a 256-point frame on the original clip. At every itreation, I calculate the DFT of the frame, multiply it with ...
0
votes
1answer
33 views

Implementing a finite impulse respone (FIR) filter for computing the derivative of a discrete signal

I am trying to reimplement an algorithm on my own. In the description of the implementation, it's written that they compute the derivate of a series of value using a [-1/2, +1/2] finite impulse ...
0
votes
0answers
46 views

How to obtain exponential decay peaks from damped signal in python? [closed]

I have a signal where I would like to implement a peak detection algorithm where it only collects peaks that follow exponential decay behaviour and stop at a certain height. Here is an example of a ...
1
vote
1answer
30 views

How to apply band-pass filter and get the filtered back from frequency to time domain in python?

I know this is basic for signal processing, but, I am not sure what is wrong about my approach. I have a signal that behaves as damped sine signal with a sampling frequency of 5076Hz and 15,000 number ...
1
vote
1answer
24 views

Does Discrete Wavelet Consider Sampling Frequency or Cutoff Frequency of Bandpass Filter?

I have EEG signal with a sampling frequency of 128 Hz, and filtered from 1-30 Hz using a bandpass filter. Now I want to know ...
0
votes
1answer
38 views

Detect lines transitioning to blobs in images

I have the following images (in high resolution, uncompressed). When the process starts, the left image is displayed and it ends something similar to the right image. The first image shows labyrinth-...
2
votes
0answers
38 views

Autocorrelation not as expected

I am trying to find the autocorrelation function on the intensity of a pixel over time stored in an array "Intensity". Usually one would expect the highest point to be at t = 0 and then decay. I am ...
1
vote
1answer
78 views

Auto Tune Shifting

So i have an algorithm that gets the fundamental frequency of windows, and can shift the pitch of each window as well (by a factor of x). For example. if x is 2 and the f0 is 440, the resulting f0 ...
0
votes
0answers
112 views

Algorithm that Fills the White Holes Within the Character Image

I have this degraded image : Using paintbucket tool in Paint.NET Windows application, I fill the character image black. My ...
0
votes
1answer
26 views

Zero peaks in fft data even after subtracting mean

I have a time series sensor data. It is for a period of 24 hours sampled every minute (so in total 1440 data points per day). I did a fft on this to see what are the dominant frequencies. But what I ...
0
votes
0answers
14 views

scipy.signal.deconvolve not working, Blind deconvolution in python

I am trying to deconvolve my original signal with a given wavelet (Ricker wavelet). But scipy.signal.deconvolve is not giving any output to the signal. Impulse signal can be generated by below code. ...
0
votes
1answer
29 views

Cochleagram vs STFT for CNN-based speech segregation

I’m working on a project (python-based) that would use ideal ratio masks (IRMs) as a basis for cleaning noisy speech in various environments. Specifically, this will be accomplished through the use of ...
0
votes
0answers
9 views

Calculate coherence ratio in HRV

According to this paper, coherence is assessed by Identifying the maximum peak in the 0.04–0.26 Hz range of the HRV power spectrum, calculating the integral in a window 0.030 Hz wide, centred on the ...
0
votes
1answer
31 views

Python code for QPSK modulator [closed]

Have any of you done anything like QPSK Modulation in python? I am in the middle of it and having problems in setting up bits? like odd and even bits. Have you got any idea? Regards, Sam
0
votes
0answers
17 views

How to generate the filter bank for a wavelet adapted to a pattern?

Some textbooks like Daubechies (1991) and Strang & Nguyen (1996) give algorithms to construct wavelets with specific properties. But, I am trying to construct a filter bank for a wavelet that is ...
2
votes
0answers
45 views

Friendliest python library for fixed point algorithm simulation

My primary programming language is python. Is anyone aware of solid python libraries to simulate fixed point algorithms in python? A quick google search revealed this: https://pypi.org/project/...
0
votes
1answer
15 views

How to extract the Freezing Index from Accelerometer data?

I'm working on a project to detect Freezing of Gait episodes for Parkinson's Disease patients, and according to this paper and other ones, extracting the freezing index which is "The power in the “...
1
vote
0answers
19 views

Noise level estimation using Hildebrand & Sekhon method

I have some data from a radar to process in order to find the moments and in turn the wind speeds. I have no prior knowledge in signal processing so it's giving me a hard time to estimate the noise ...
0
votes
0answers
17 views

Smoothing jagged lines in an image?

I have an image like this - I would like to smoothen the lines in this (as you can see they lines are a little jaggy.) How can I do this? I obtained the lines by isolating them from another image ...
0
votes
0answers
7 views

how to use robot framework to launch unit tests on matlab?

I Know the syntax of rfw and and I want to make some unit test, for some kernels and functions in matlab and I need some help to begin with
1
vote
1answer
56 views

Pitch shifting with bins creating large feedback

I am attempting to create a pitch correction algorithm. I started by performing a test. The test goes as such: Get WAV file Split it into bins of size n (512 in my case) Shift each bin by 2 semitones ...
0
votes
1answer
34 views

Construct IFFT from only the major frequencies of an input signal?

I have data which when plotted looks like the green line in the below image. The data is from the walking-motion of a reinforcement-learning-model in a simulation and therefore the values do not ...
0
votes
1answer
20 views

What does librosa.load return?

I'm new to signal processing and I'm working with librosa library quite a bit. I would like to know what is the information that is returned by librosa.load function when I read a audio(.wav) file ...
0
votes
1answer
42 views

What function to apply a Metamorphopsia (grid warp) translation?

How would I go about finding or creating a function to warp images dependent on grid lines surrounding an origin (I don't wish for a grid on my actual images): It should work in practically the same ...
1
vote
0answers
60 views

Is rotation of a Fourier transform the same thing as Fourier transform of a rotation?

I'm working on an image processing problem and wondering if DFT(rotation(image)) == rotation(DFT(image)) (1). My final goal is to apply rotations in the Fourier domain then do an inverse Fourier ...
0
votes
2answers
42 views

Record Signal after Threshold Reach in GNU Radio

I would like to use GNU radio to begin recording a predetermined number of complex samples to a file sink automatically as soon as a signal magnitude threshold is reached. For example, as the gnu ...
0
votes
0answers
26 views

Resampling assessment

I'm trying to figure out which of the resampling methods is best in my job. Comparing the original image vs. bilinear, bicubic, bicubic spline, lanczos. For now I have considered metrics like MSE RME ...
1
vote
0answers
45 views

Signal processing

I am quite new to signal processing and I have got the signal in picture. I'm working with Python. The central part has some sort of periodicity and it is the one I want to retain, whereas I want to ...
0
votes
0answers
16 views

Can someone help me this db transform applied on melspectogram?

I have read some audio processing codes written in Python : ...
0
votes
1answer
49 views

Upsampling implementation

I have problem with upsampling implementation in the following way: My code: ...
0
votes
0answers
31 views

Measuring Voltage Fluctuations (RMS)

I am currently working on the Hodgkin-Huxley model and would like to show that the absolute amplitude of the current fluctuations increases with the area - I thought of the RMS value as a reasonable ...
1
vote
0answers
35 views

How to take the inverse FFT of Welch's power spectral density in Python?

I have calculated the power spectral density of a weakly-stationary signal using Welch's method (as implemented by scipy.signal.welch in Python), and am looking to take the inverse Fourier transform ...
0
votes
0answers
33 views

How to calculate the plane at infinity? either in Matlab or Python

I tried to implement this function to compute the plane at infinity $n_\Pi$ from the equation: where $w^{-1}$ is the image of the absolute conic IAC, $M_j$ is the Projection Matrix of image $j$, but ...
0
votes
0answers
23 views

How to save MFCC features and frame energy of several wav files to one .npz file for machine learning training?

I am creating a English-Italian corpus of around 100 hours of English audio from LibriVox aligned with their Italian textual translation. The alignment is at a sentence level and the corpus consist of ...
0
votes
0answers
11 views

How to correctly perform Continuous Wavelet Analysis

I have a signal coming from an accelerometer which has already been filtered in the band 0.5-15Hz. I would like to understand in particular how frequencies are distributed in two bands (0.5-3, 3-6) ...
2
votes
3answers
52 views

Circuit simulator with variable simulation time step. How to obtain FFT afterwards?

I know that I am not the first one with this problem, but I didn't manage to find the proper answer, so I hope you would like to help me. From an electric circuit simulator, I simulated my circuit in ...
0
votes
1answer
27 views

Wavelets / Identifying bursty signals

I thought my network was experiencing outages. I collected bandwidth (Mbps) measurements every 30 min. A cumulative probability distribution shows the probability that bandwidth will exceed any given ...

1
2 3 4 5
16