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Questions tagged [feature-extraction]

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1answer
25 views

what is the output of MFCCs?

I had calculated 13 MFCCs coefficients of a speech signal and i got output in the form numerical vectors please see below figure. My confusion whether it is in time domain or frequency domain. suppose ...
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2answers
44 views

Understanding of Histogram-of-Oriented-Gradients

I am learning about HOG and I understand it from here. A well-explained page with an example. I am not understanding this concept that how it works A 16×16 block has 4 histograms which can be ...
0
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2answers
60 views

Scratch Detection On Noisy Textured Surface

I wish to extract long thin scratches from the noisy background image.I have tried several ways such as stacking smoothed image with input image to remove some of the noisy background patch before ...
0
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1answer
72 views

Extracting feature from audio track using DWT

Our teacher gave us an assignment: Write a program to transform an audio track to time - frequency domain, and create a vector include at least 4 features extracted from transformed output signal. I ...
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0answers
93 views

How do I extrapolate a 1D chirped signal?

Following a past question, I'd like to extrapolate a signal like the one below: (red is signal, blue is the the extrapolated ) ...
1
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1answer
34 views

How does a telephone change your voice? [closed]

Is it due to vocal length normalization during MFCC? Please be kind enough to explain.
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1answer
23 views

Is it possible to classify biosignal data based on feature extraction through multiple linear regression model? [closed]

i have 16 channel 2 class motor imaginary right hand ,right leg data.IS it possible to classify this through multiple linear regression model based on feature extraction?can i classify 3 class data ...
0
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1answer
116 views

How can I extract information about timbre from a .wav file. In which form can I study those features?

To study the frequencies of a piece of audio, we can generate a spectrogram from that audio file. I'm wondering how the features of timbre are saved in such tiny wave files, and how we can extract ...
0
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0answers
53 views

spectral kurtosis binary masking (matlab)

Following this research paper, under section 4, equation 13, we can calculate the binary mask. However, I am a little bit confused on how to do this, considering I have already a complex STFT of a ...
0
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0answers
91 views

Feature Extracting from an image from JAFFE database using gabor filter

I am trying to implement a feature extractor using gabor filter in MATLAB. I have taken images from the JAFFE Database. Here is my code: ...
0
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1answer
57 views

How to make series circle shift invariant

I have a series of numbers. They may be integer, floating, or ...
0
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0answers
77 views

Derivative of a MFCC matrix

While reading this (see feature extraction section, subsection 4.1), I came across the following: The per-frame values for each coefficient are summarized across time using the following summary ...
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0answers
98 views

Determine DoG (Difference of Gaussians) extrema from multiple octaves in a scale space

I am attempting to program SIFT in C++ without any libraries(bad idea, should have used matlab). So far, I have computed extrema points from 2 DoG images per octave of a scale space consisting of 5 ...
1
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1answer
138 views

Common Spatial Pattern for EEG Signals

I am having difficulty in understanding the use of CSP for EEG signal feature extraction and subsequently. Since I am using two classes, this query will be restricted to it. In essence CSP requires 2 ...
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2answers
338 views

How to extract features of individual spikes in non-negative signal?

I have data of non-negative (in the sense there's no signal below baseline) spiking waveforms, which are in the form of a 1D array of numbers: Spikes that cross some threshold are considered real ...
0
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1answer
473 views

MPEG-7 low-level audio descriptors

I'm working on an application which need to use the full set of 17 MPEG-7 low-level descriptors. Is there any library I can use for it? Preferably with a Python wrapper/API...
0
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1answer
197 views

extracting MPEG-7 low-level audio descriptors using essentia

According to https://www.ntnu.edu/documents/1001201110/1266017954/DAFx-15_submission_43_v2.pdf, the audio processing toolbox Essentia includes the 100% of MPEG-7 low-level audio descriptors. However I ...
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0answers
29 views

zernik moments and Local binary pattern

Both of zernik moments and Local binary pattern (LBP) are feature detectors and can achieve rotation invarient. How can they achieve rotation invarient over an image? What are the advantages of ...
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3answers
138 views

Features Used for Instrument Recognition?

I'm building a neural network for instrument recognition based on the IRMAS data set. However, I'm a bit at a loss for what features to use. MFCC seems to be quite popular but extracting this per ...
0
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1answer
74 views

how to describe the color of a small image patch?

I want to describe the color of an image patch (say of size 5x5) centered around a pixel of an rgb image. The most straightforward way to do that is to calculate the average color over that patch and ...
1
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1answer
1k views

Feature Extraction of FFT for One Class SVM

I'm looking for a good way of extracting features from the frequency domain of vibration data for a one-class support vector machine. The image below shows an example from the dataset found in this ...
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0answers
46 views

Dimension of the output of Spectral Entropy functon

This Question refers to an answer from Peter K. https://dsp.stackexchange.com/a/30535/30743 where he explains the difference or similarity of Spectral Flatness and Spectral Entropy. My Question In ...
1
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1answer
830 views

Why is LPCC and LPC used in speech recognition

I am currently trying to understand why LPCC and LPC is being used in speech recognition and why? LPC as I understand is model similar to source filter model, modelling speech production, and LPC ...
0
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1answer
65 views

Extract same in phase signal from 3 different sources with shared delayed noise?

If I have 3 signals coming from 3 microphones with noise $n$ delayed like this: $S_1(t) = x(t) + n(t+\phi_1)$ $S_2(t) = x(t) + n(t+\phi_2)$ $S_3(t) = x(t) + n(t+\phi_3)$ Their shared feature $x(t)$...
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0answers
194 views

Haar Feature calculation procedure for 24x24 image

I am learning image processing with Haar features. I am reading a thesis paper and they said that they are calculating Haar features for 24x24 resolution image. And showed the calculation table as ...
1
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4answers
366 views

Palm Pilot Graffiti

I have been completely unable to find details on the underlying model that is used for the Palm Pilot Graffiti handwriting recognition. Given the computing power available for handheld PDA technology, ...
1
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2answers
508 views

Detecting trough widths and locations in 1d signal

I have the following function obtained from averaging 2d camera image over one axis, where detection of aligned objects is desired: I need to detect (roughly speaking) locations and widths of the ...
2
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1answer
669 views

MFCC delta: How to compute delta, in real time, with no future frames?

I am trying to compute Delta coefficients for real-time audio analysis. As far as I know, a valid formula is: $$d_t= \frac{\displaystyle\sum_{n=1}^{N}n\left(c_{t+n}-c_{t-n}\right)}{2\displaystyle\...
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0answers
23 views

Recognize irregular repetition of unknown feature (stamps at random locations)

I have an image which is generated by convolution between (1) a simple small patch and (2) larger image composed of localized point-like features (e.g. slat-and-pepper noise, sum of shifted $\delta$-...
0
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1answer
1k views

How to extract prosodic cues from a wav file using Python

How do I extract the following features as from wav files in Python - Voicing rate (Voice rate) - frequency of phonemes while speaking, and represents the pace of a conversation Number of ...
0
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2answers
1k views

Is there a program to extract features from an audio signal?

I am looking for a way to take a .wav file and extract features from it that could be used for further classification (the features could be MFCC statistics, an autoencoder representation, etc.). I ...
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0answers
383 views

What are the drawbacks of Harris corner detector? [closed]

What are drawbacks of Harris corner detection when trying to match features in a stereo pair? I notice that whenever I use Harris corner detector to match features, images with strong occluded areas ...
1
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0answers
52 views

Image feature extraction for discrimination

I am using linear/quadratic discrimination to guess who is the artist of a painting. All the images are RGB format and I use matlab. I have used both original image and images that are resize to be ...
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0answers
78 views

Is there a way to extract the difference between the 2 signals? Fitting?

I'm very new to signal processing and have been struggling this far. I have a device that measures the signal due to the magnetization of iron particles. In order to calculate the response of the ...
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0answers
222 views

VLFEat: How to extract the SIFT descriptor without SIFT feature detection?

I am using the MATLAB interface to the VLFeat toolbox in order to calculate a SIFT descriptor for image patches extracted around key points. Due to the greater framework of what I'm doing, I cannot ...
6
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1answer
3k views

What's the correct graphical interpretation of a series of MFCC vectors?

I'm studying speech-recognition, in particular the use of MFCC for feature extraction. All examples I've found online tend to graph a series of MFCC extracted from a particular utterance as follows (...
0
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1answer
107 views

feature selection for classification for rare classes

I have a spectrogram of a signal and want to classify it. I used different features such as MFFC, the density of power spectrum and other common features and classify using the random forest, but I ...
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2answers
603 views

Using Convolution as Feature Extraction

I am now studying image processing in my spare time. My understanding of convolution is about 'response to a specific filter': When we have a raw image, or raw signal; and a filter, aka kernel; we ...
0
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1answer
88 views

What is the use of perception calculation in Speaker Identification?

I'm currently trying to find audio features to train a neural network that distinguishes people, and I came across MFCC which is used a lot for speech verification. As far as I understand the ...
0
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1answer
489 views

Comparing band-pass filters and convolutional kernels?

I am currently working on extracting features for speech recognition purposes. I wanted to try an approach similar to MFCC features in which the center frequency of each band pass filters are placed ...
1
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1answer
2k views

How do I get texture feature images from GLCM texture analysis?

In this paper under section 2. "Proposed Methodology", the author creates a GLCM from an image and then extracts texture features resulting in a new image for each feature. I've seen other authors do ...
0
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1answer
716 views

Feature Vector from an audio signal [closed]

I want to develop a feature vector from an audio input. Up to now, I have identified fundamental frequency, max phonation time, timbre to be among the key features to be identified. Can someone ...
0
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1answer
98 views

How signal moments work?

We know that moments extract important features of a signal that has no redundancy. For example Zernike moment gives us rotation invariant data of a signal like image or Fourier gives us frequency of ...
1
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1answer
135 views

Music Recommendation [closed]

I have idea of creating Content based Music recommendation system based on Music signals, Now I am asking how I can extract signal features from Music and how to represent them. There after I may find ...