Questions tagged [frequency-analysis]
361 questions
41
votes
8 answers
How do I run a high pass or low pass filter on data points in R?
I am a beginner in R and I have tried to find information about the following without finding anything.
The green graph in the picture is composed by the red and yellow graphs. But let's say that I only have the data points of something like the…
![](../../users/profiles/23118.webp)
hlovdal
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25
votes
3 answers
Explaining The Count Sketch Algorithm
Can someone explain how the Count Sketch Algorithm works? I still can't figure out how hashes are used, for example. I have a hard time understanding this paper.
![](../../users/profiles/320161.webp)
neilmarion
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20
votes
4 answers
How to calculate sound frequency in android?
I want to develop app to calculate Sound frequency in Android. Android Device will take
Sound from microphone (i.e. out side sound) and I have one color background screen in app.
on sound frequency changes i have to change background color of…
![](../../users/profiles/1035484.webp)
Ashish Wadatkar
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13
votes
2 answers
Determine "wiggliness" of set of data - Python
I'm working on a piece of software which needs to implement the wiggliness of a set of data. Here's a sample of the input I would receive, merged with the lightness plot of each vertical pixel strip:
It is easy to see that the left margin is really…
![](../../users/profiles/464744.webp)
Blender
- 257,973
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10
votes
2 answers
Simple code to calculate frequency of Live Mic Audio using WebAudio API
I have website in which I need to display the frequency of the Live Mic Audio.
I have a this code, but its extremely difficult to understand (It uses Fourier Transform and all).
On some research I got to know of getByteFrequencyData() which returns…
![](../../users/profiles/3426358.webp)
FlyingAura
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9
votes
1 answer
how can I statistic my key press frequency and count
I am try to remap my keyboard to type better.
But I need to know the frequency of each key include symbol, It will be great if include tab shift ctrl. I need all the keypress acounting not only frequency of letters appears in english words.
I am…
![](../../users/profiles/443966.webp)
guilin 桂林
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9
votes
1 answer
How do Mel Frequency Cepstrum Coefficients work?
I allready have FFT and pitch + absolute frequency calculated in real-time from input of microphone.
Now I want to calculate the timbre.
I saw Mel Frequency Cepstrum Coefficients - MFCCs but I didn't understand it very well.
Can someone give me some…
![](../../users/profiles/189965.webp)
André
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8
votes
3 answers
Cleaning up noisy Cepstrum results
I've been working on a simple frequency detection setup on the iphone. Analyzing in the frequency domain using FFT results has been somewhat unreliable in the presence of harmonics. I was hoping to use Cepstrum results to help decide what…
![](../../users/profiles/602162.webp)
brodney
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8
votes
2 answers
FSK Demodulation - Parsing Japanese EWS Data
【This is not a duplicate. Similar questions are about scenarios where people have control over the source data. I do not.】
In Japan there's something called the "Emergency Warning Broadcasting System." It looks like this when activated:…
![](../../users/profiles/3073472.webp)
aaa
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- 5
8
votes
1 answer
Efficient algorithm to find most common phrases in a large volume of text
I am thinking about writing a program to collect for me the most common phrases in a large volume of the text. Had the problem been reduced to just finding words than that would be as simple as storing each new word in a hashmap and then increasing…
![](../../users/profiles/172776.webp)
TheOne
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7
votes
2 answers
Pyplot sorting y-values automatically
I have a frequency analysis of words said in episodes of my favorite show. I'm making a plot.barh(s1e1_y, s1e1_x) but it's sorting by words instead of values.
The output of >>> s1e1_y
is
['know', 'go', 'now', 'here', 'gonna', 'can', 'them', 'think',…
![](../../users/profiles/8816299.webp)
robert strickland
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7
votes
6 answers
Improving frequency resolution of FFT output by limiting frequency range?
I am new to FFTs and signal processing, so hopefully this question makes sense and/or isn't stupid.
I would like to perform spectrum analysis on a live audio signal. My goal is to find a good tradeoff between responsiveness and frequency resolution,…
![](../../users/profiles/387374.webp)
gga80
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7
votes
2 answers
Analyse frequency of mp3 files with python
I am trying to write a Python script to read an MP3 file and perform some analysis on the frequencies in it. In particular, I want a spectrogram (frequency vs time) as output.
However, when I read the file using open() and piped the contents to a…
![](../../users/profiles/3518846.webp)
DrNightmare
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7
votes
1 answer
Lucene 4.4. How to get term frequency over all index?
I'm trying to compute tf-idf value of each term in a document. So, I iterate through the terms in a document and want to find the frequency of the term in the whole corpus and the number of documents in which the term appears. Following is my…
![](../../users/profiles/220647.webp)
chepukha
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6
votes
3 answers
Need an audio analysis library to create real time feedback from audio file?
Real-time is not necessarily required, however I am creating a game for my final year project and I wish to use the power of audio to create dynamic levels based solely on a music track that is playing. I aim to create this game for the PS Vita…
![](../../users/profiles/1936856.webp)
ProperBritish
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