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1answer
16 views

STFT multiplied with Gaussian Impulse vs STFT multiplied by unit height rectangular impulse

I am currently analysing my signal by looking at its spectrogram to determine the sinusoidal frequency content at the local sections of my signal overtime. I can do my spectrogram in 2 ways: ...
4
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1answer
119 views

Issues with the smoothing operator in coherence estimation using the complex Morlet (Gabor) wavelet

The goal I wish to compute the coherence estimate using the continuous wavelet transform (CWT) of a real-valued signal with the complex Morlet (a.k.a. Gabor) wavelet. I compute the cwt of the signal ...
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0answers
20 views

Wavelets and filters?

I've tried using the search function to answer this question, but haven't found any explicit answers. I'm trying to study Gabor and log-Gabor filters. Most of the content I find is on Gabor wavelets ...
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0answers
28 views

Gabor filter bank for gist features

I was reading a paper about Gist features. I was interested about its code implementation which i found it here). Into LMgist.m there is a function called createGabor, this is the code: ...
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0answers
55 views

Gabor filter bank spatial frequency parameters

I've been trying to learn about using Gabor filters to extract features from an image. There are some research papers that list their spatial frequency parameter in the form of x:y cycle per pixels in ...
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2answers
301 views

How to visualize and understand Gabor filter using matlab

I am reading a paper, in which the author defines gabor kernels as : $$ \psi_{\mu,\nu}(x,y)=\frac{\lVert \mathbf{k}_{\mu,\nu} \rVert}{\sigma^{2}}\exp (-\frac{\lVert ...
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0answers
97 views

Box filter approximations for oriented gabor filters

I'm currently working on a library to generate synthetic fingerprints using the SFinGe method (by Maltoni, Maio and Cappelli) link ...
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2answers
134 views

Is Gabor uncertainty a feature of the Fourier transform, or of nature?

By Gabor uncertainty, I mean the principle of uncertainty as applied to signals — with the result that you can't have arbitrary time and frequency localization. By way of background to my question, ...
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0answers
45 views

question about the frequency of Gabor filters

The Fourier transform of 2D Gabor filters is shown below: F is the radial frequency of the Gabor functions. Another parameter Fm is denoted as highest central frequency. Fr is the constant ...
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2answers
83 views

Is there any difference between the 2D continuous and discrete Gabor filter when it comes to MATLAB implementation

I want to know the difference between the 2D continuous and discrete Gabor filter when it comes to Matlab implementation. I found many files related to 2D Gabor filter on Mathworks File Exchange but I ...
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1answer
2k views

Understanding the Gabor filter function

I need to implement a script for generating features from an input image by using the Gabor filter. I have no past experience of wavelets and I'm just learning Fourier analysis (I understand the basic ...
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0answers
50 views

How can I apply a Gabor filter to a sine waveform?

I am an ECE student, and I am doing my project on underwater communication. The main concept of my project is to denoise the signal by using UFB and WPD algorithms, and giving that output to a ...
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2answers
1k views

gabor filters for digital image processing

For the application of Gabor filters in feature-based (e.g. lines and edges in images) digital image processing, it is desired that the DC component is 0. Why is this so? What effect does it have ...
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2answers
101 views

how can i call the input data in wavelet transform and generate code for gabor wavelet manually? [closed]

I am an ECE student, and i am doing my project I want to generate a code for gabor wavelet transform. I have no idea could you help me with a sample program I have DNA as input sequences and how ...
3
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1answer
196 views

proving that a log gabor filter has 0 DC offset

I have read somewhere online that the log gabor filter has an advantage over the gabor filter, in the sense that it has 0 DC component. How do you prove this property mathematically? Thanks in ...
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2answers
185 views

Apply Singular Value Decomposition on Gabor filters

According to my question in this link, I applied (with a big help from lennon310) the separability of Gabor filters of any orientation. The only disadvantage of this method is the convolution in the ...
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1answer
1k views

difference between Gabor and log-Gabor function

I am reading a paper using log-gabor filters for feature detection. I was thinking about the difference between Gabor filters and log-gabor filters. Can anyone tell me the difference(s), and a way to ...
0
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1answer
95 views

filter bank of gabor filters with different frequencies and orientations

I was reading a paper which uses a filter bank of gabor filters with different frequencies and orientations. However, I often see the construction of a filter bank of gabor filters with different ...
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1answer
153 views

gabor wavelet and gabor transform

I was reading a paper 'A Flexible Framework for Local Phase Coherence Computation' (paper URL) on using wavelets for local phase coherence. I just want to be sure. Is the gabor wavelet the same as the ...
0
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1answer
170 views

Book recommendations on Gabor filter and Fourier series

I'm starting to learn about Gabor filters and Fourier series. I need to make a presentation on Gabor filters in a few months, so I need quality references for the presentation. Does anyone have any ...
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2answers
67 views

Precalculate the Normalization of a filter size

If we have an Image I and a Gabor filter created at specific size and orientation, assume that is 11x11. I saw some persons who normalize the size of the filter, ...
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1answer
90 views

Convolution in image processing

Does anyone know how to write arg min code in matlab with explanation? I am referring to a paper for my research. I am not sure whether I can paste the paper link here. At first, I try to do feature ...
0
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1answer
368 views

Gabor Filter Parameter

I am doing research on images using gabor filter. I have read the following post: Apply a Gabor filter to an input image There must be some formula to determine the value for ...
0
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1answer
81 views

frequency components of discrete Gaussian-windowed signal

When we are do a discrete Gabor transform on a 1D signal, we apply a Gaussian window on a segment of the signal. However, due to the tapering ends of the Gaussian window, the magnitude of the data ...
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1answer
268 views

Need of removal of dc component

I recently was studying gabor filters and came to know that they have a shortcoming that they do have a minimum but some reasonable dc component. now my question is why is it necessary to remove the ...
1
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1answer
291 views

window for short time fourier transform

When we implement the 1D-short time fourier transform, the formula is as such: $$ Sf[m,l]=\sum_{n=0}^{N-1}f[n]g[n-m]\exp\left(\frac{-i2\pi l n}{N}\right). $$ the window $g$ used is normally ...
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3answers
389 views

strange phenomenon in spectrogram of Windowed Fourier Transform [edited] [closed]

I am trying to understand how the Windowed Fourier transform works, so I used Matlab to create an artificial signal, and plotted the Windowed Fourier transform using a gaussian window. $x(t) = ...
4
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1answer
186 views

Motivation for using gabor transform instead of fourier transform

I am trying to understand the motivation for the above question for signal processing and image processing? Can anyone answer this question, or provide me with resources for this?
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1answer
140 views

Variance of the Discrete Gabor Transform for practical implementation

When we design a discrete Gabor filter for a 1D signal, how do we determine the variance of the filter, depending on the time step of the signal? Is there any empirical theorem/result that we should ...
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0answers
72 views

Errata Corridge in Gabor Filter Documentation and Frequency Response

I have a really simple question regarding this tutorial I found on Gabor filters. Check the very beginning section, equations (1), (2), (3) and (4). Is there any chance that equation (4) is missing ...
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1answer
199 views

How do I start studying Gabor Filters ?

I know very basic image processing. Please suggest me how do I and where do I start learning Gabor Filters ?
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3answers
1k views

What's the difference between the Gabor-Morlet wavelet transform and the constant-Q transform?

At a glance, the constant-Q fourier transform and the complex Gabor-Morlet wavelet transform seem the same. Both are time-frequency representations, based on constant-Q filters, windowed sinusoids, ...
1
vote
1answer
338 views

Difference between Gabor filter implementations

I was reading a paper and came across this: I'd like to implement this in matlab, therefore I initially searched for a premade implementation. I stumbled upon this: ...