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Questions tagged [peak-detection]

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1answer
50 views

Filtering and peak finding

I have an observed signal which is the norm of the sum of two 3-vectors: $$ S(t) = || \mathbf{A}(t) + \mathbf{B}(t) || $$ Now, I have full knowledge of the vector $\mathbf{A}(t)$, $$ \mathbf{A}(t) = \...
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2answers
63 views

Detection of sharp peaks in an audio signal

I have an audio signal and I'm interested to detect the very sharp peaks. If I zoom, here is something that should NOT be detected (this is voice actually): NO GOOD Here is something that should be ...
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0answers
27 views

Peak Analysis vs Machine Learning

I am unsure about which approach is "better" (less time good accuracy) for classifying gestures: The system is a doppler radar that returns I and Q signals Approach 1: Have several subject perform ...
0
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1answer
75 views

Threshold for peak detection of noisy signal in frequency domain

I have a noisy signal (Gaussian Noise) with a known SNR and known Noise variance. This signal contains a number of Frequency components. My ultimate objective is to detect the components of the signal....
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4answers
157 views

Estimate peak width from a vector that is a superposition of unknown number of identical Gaussian peaks with different heights?

If you have a vector that is a superposition of an unknown number of identical Gaussian shaped peaks/impulses of unknown width (but all the same width) and different amplitudes (with Poisson or ...
3
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1answer
84 views

Chromatogram peak detection - bunching vs others?

Reading presentations from existing tool providers I noticed that in order to detect peaks they first use bunching (average N points) and then use slope and curvature to detect peaks. I'm guessing ...
0
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1answer
38 views

How to differentiate an empty aerosol from a full one using only sound measurements?

The challenge I have is to detect an empty spray container using sound measurements only, since I can't place any sensor directly into the container because of the mechanism that tightens it. My main ...
0
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1answer
495 views

Checking for VHF pulse with SDR and python

So I have a small NooElec Software Defined Radio and I've got it working well with my Raspberry Pi using GQRX as a controller and to visualize the SDR output. My goal though is to use a python script ...
0
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1answer
118 views

Peak Detection Of Every Pulse

I have this signal as the following figure: Now, I need to know each beginning index of each pulse as described in the following figure: I have tried to detect the peaks through obtaining the cross ...
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2answers
49 views

What should I do with FFT result array from microphone input? [duplicate]

I currently want to create a small pitch detector and I have to say that I am very new in this topic of signal processing. At the moment I implemented the FFt algorithm and I got an array of window ...
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2answers
85 views

Pitch detection of two following music notes (C0 and C0#)

Hi signal processing community, currently I am working on a pitch detection tool which should work on audio input files (or later also instrumental or voice from microphone) to say which music note ...
0
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1answer
162 views

How to get coordinates of complex RTL-SDR signal?

As I have already explained here (https://stackoverflow.com/questions/49358449/python-how-to-get-coordinates-of-complex-rtl-sdr-signal-peaks?noredirect=1#comment85722604_49358449), I need to find the ...
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2answers
377 views

Curved noise floor and ugly unexplained peaks after FFT

It has been so long since I studied this at University, so I'll better ask here if I'm doing something really wrong here. I'm using a USRP frontend for L1 band surveillance. I want a 20MHz bandwidth, ...
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3answers
167 views

Extract breaths from respiratory signal, i.e. peak detection

I am trying to extract breaths from a respiratory signal, which is essentially peak detection. See the example below for what such a signal looks like. This particular signal looks rather clean, ...
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1answer
194 views

Harmonic Product Spectrum algorithm. I dont understand one step

I was looking some Harmonic Product Spectrum algorithm examples and I came up with this: ...
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1answer
759 views

Name of peak finding algorithm

I've been using this implementation of a peak finding algorithm and it works pretty well. I'm wondering if this particular algorithm has a name? Python code: ...
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1answer
38 views

What does this block operator mean?

What does this block do? It's part of a block diagram for a RMS/Peak detector.
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0answers
385 views

Python, How to fill a gap or filter the peaks out of a signal with morphological filters?

I have a signal presenting 2 peaks (the second half period of the signal is a mirroring of the first half). I want to filter out those peaks (circled in green) or fill out the gap caused by them (so ...
3
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1answer
5k views

Taking audio frequency and picking out peaks (Peak Detection)

So I have a unique challenge. I want to take an audio file, and pick out the peaks in the samples and plot that onto a graph. Each point based on the amplitude/pitch(?) will be represented as either a ...
1
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1answer
1k views

How do spectrum analyzers detect peaks?

Using peak search, I'm able to put the cursor on any of the several peaks on the spectrum analyzer display. I am trying to do something similar in software, with the output of the FFT of the radio ...
3
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1answer
186 views

How to detect peaks ignoring soft declivity?

I have to detect repetitions in a signal, and I am managing to do it by finding peaks and valleys, and cutting the desired pieces. The following figure shows the pattern wanted, shaded areas are the ...
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0answers
163 views

Cross Correlation shows peak at the same location every time

I have a signal which is taken from an accelerometer and I'm trying to match patterns between different windows of the signal by cross correlation. To do this I take different windows of the signal, ...
1
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1answer
137 views

How can I get the uncertainties for peaks on an image?

When pick the peak points on an image, e.g. the matrix made by peak in matlab as this one, I can use max to get the index of ...
3
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1answer
207 views

Unexpected peaks in spectral analysis

I am doing the spectral analysis of some antenna recorded signals by computing PSD (logarithmic absolute value of the FFT) and the spectrogram of the signal. The problem is that I get some unexpected ...
3
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0answers
120 views

Peak detection for signals that contain high frequencies

I have an question about peak detection. My purpose is creating a plot with an impulse response and the decay line at / above it. What I see till now is that there are two options for finding peaks: ...
1
vote
1answer
122 views

Detecting expected patterns in repeated measurements

I am new to signal processing and I am trying to learn myself. To understand what i am interested in, let me show this on example (note that this is just a random example to illustrate). Here is some ...
0
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1answer
405 views

Periodicity of peaks within a signal

I have a signal, in which i want to detect the period of the peaks, that exist within this signal: for example : After each 5mm or (5 seconds depending on the sampling rate and speed of my motor) i ...
3
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0answers
110 views

how to detect number of syllables in a batch of audio recordings?

I have a corpus of short speech samples from Kiswahili speakers, and I want to detect the number of syllables in each audio recording. How should I approach this task? Background: I asked a ...
1
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1answer
864 views

DFT normalization for amplitude estimation

After an interesting recent answer, I'm doing some research on proper DFT normalization for sinusoidal peak estimation. It's clear that to get the correct amplitude from DFT peaks we need to normalize ...
0
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2answers
805 views

Getting a more accurate frequency read from autocorrelation and peak-detection algorithm

For a project I am attempting to create an automatic tuner for a guitar, which reads the audio from the guitar jack, determines the frequency and adjusts the string by a motor. Using http://www....
1
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1answer
134 views

reducing MIPS in detecting tones

Currently our software is detecting tones using FFT and checking if there is only a single peak in frequency spectrum. Our software needs to know what kind of input it is before taking action. So we ...
0
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1answer
867 views

Finding peaks in an Audio spectrogram

I'm using gist.github.com/sixtenbe/1178136#file-peakdetect-py to find maximum peaks in my spectrogram. I used ...
0
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1answer
155 views

Is there a relatively easy way to detect likely real-time peaks in discrete-time data?

Let's say I have a set of data over time, t: [0, 4, 6, 7, 7, 6, 4, 0] It seems likely that this data would peak at ...
2
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0answers
432 views

Peak detection techniques

I'm using a cell-averaging constant false-alarm rate (CA-CFAR) detector to detect peaks like the first one in the following plot: The magenta line is the adaptive threshold, which is the local ...
2
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0answers
161 views

Absolute value vs. power (to make a signal positive-only)

In order to make a signal positive-only, I have the choice between taking the absolute value and multiplying the signal by itself (i.e. taking the signal to the power of two). Obviously, multiplying ...
2
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1answer
1k views

MUSIC algorithm for peak detection

On Wikipedia, is written that MUltiple SIgnal Classification (MUSIC) is an algorithm used for frequency estimation. One purpose of estimating the spectral density is to detect any periodicities in ...
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1answer
2k views

Wavelet-based C/C++ Peak finding libraries

What wavelet-based peak finding functions are there for C++? I'm looking for something similar to: http://docs.scipy.org/doc/scipy-0.15.1/reference/generated/scipy.signal.find_peaks_cwt.html. ...
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0answers
118 views

“Normalizing” PSD of unequal window lengths

I am acquiring time-varying data with unequal sampling (nature of the source). When building a spectrogram, I have the algorithm choose sample blocks that are are -nearly- the same length -but, they ...
3
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3answers
4k views

Good way to detect pulse with known width with background noise?

I'm dealing with a light sensor tracking a bursting LED. Unfortunately signal is weak and there are other light sources in environment. I've used optical filters on sensor but there is still some ...
2
votes
1answer
259 views

How to detect peaks in a microcontroller?

In the context of a microcontroller, I have much less memory and far less processing power. This means, I can only buffer a reasonable window of samples (e.g. 16 or 32), and may not be able to use ...
1
vote
1answer
542 views

What DSP method are consumer products like the game Rocksmith and guitar polyphonic tuners likely to use for multiple f0 detection?

The game Rocksmith and some polyphonic guitar tuners (like the PolyTune) are able to recognize, at least to some extent, multiple fundamental frequencies in single-source audio. I know there are some ...
1
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1answer
308 views

Uses of peaks in audio auto-correlation

Do you know of any algorithms for audio processing that make use of peaks in auto-correlation function? I am currently involved in research on mapping methodology for dynamic algorithms. I came ...
0
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1answer
322 views

how to detect signal noise

I have data from a power transformer that has a frequency of 60 hz. Sometimes there are faults in the system and causes a large spike in the reading of the transformer. What I want to do is run the ...
3
votes
3answers
414 views

Filtering data so that only rising edge is left

I have data that looks like this: Sometimes the data has a higher point in the middle of the shallow slope I want to find a way to filter the data such that it smooths it and leaves the first rising ...
2
votes
1answer
765 views

O(1) peak segmentation algorithm in matlab?

I have an intensity image, similar to the image below. I would like to very quickly, segment this image, into separate peaks. Where each peak is labelled, and segmented. A notional segmentation of ...
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0answers
925 views

In a signal there is a peak, I want to find the start of the peak and the end of the peak

I want to the start time and end time for the peak shown below. The start and end are shown by the marked circles in the fig As there are number of such plots and want to know start and end time for ...
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5answers
4k views

How to detect impulse like peaks - Matlab

I have a signal which is a matched filter output. whose values are given here: Amplitude values Input to this matched filter is radar return signals mixed with additive gaussian random noise. Its ...
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0answers
644 views

Extraction of fundamental signal information-Fourier full cycle algorithm

After filtering my noisy input signal using an anti-aliasing and FIR filter, I now wish to get the basic signal information (peak voltage and impedance; $R$ and $X$) from the pre-filtered as well as ...
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0answers
403 views

Reliable peak picking algorithm?

I've written an application that estimates pitch based on autocorrelation function. I did peak picking by comparing vector values to determine whether the central one is a peak or not, but this method ...
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2answers
618 views

What is obtained from the cross correlation plot?

Let’s assume that we have two audio signals, x(t) and y(t) affected by the noise as shown below. And we would like to cross-correlate these two signals and the cross-correlation plot is shown as ...