2D Gabor Filter(Ver1,2,3)

To design 2D Gabor filter and apply it to image.

Description

Recent studies on Mathematical modeling of visual cortical cells [Kulikowski/Marcelja/Bishop:1982] suggest a tuned band pass filter bank structure. These filters are found to have Gaussian transfer functions in the frequency domain. Thus, taking the Inverse Fourier Transform of this transfer function we get a filter characteristics closely resembling to the Gabor filters. The Gabor filter is basically a Gaussian (with variances sx and sy along x and y-axes respectively) modulated by a complex sinusoid (with centre frequencies U and V along x and y-axes respectively).

Gabor filters are used mostly in shape detectin and feature extractin in image processing.

function [G,gabout] = gaborfilter1(I,Sx,Sy,f,theta);
from 'gaborfilter1' with different f(Frequency) and theta(Angle).
for example

f:0,2,4,8,16,32
theta = 0,pi/3,pi/6,pi/2,3pi/4

then for any input image like(eg. stereo.jpg)

you have 6x5 = 30 filtered images.

You can choose your desired angles or frequencies.

You can put nominaly Sx & Sy = 2,4 or some one else.

For instance I tested above example on ('cameraman.tif')(in MATLAB pictures)

I = imread('cameraman.tif');
[G,gabout] = gaborfilter1(I,2,4,16,pi/3);
figure,imshow(uint8(gabout));

• Acknowledgements: This submission has inspired the following:; Gabor filter
• Required Products: Filter Design Toolbox; Image Processing Toolbox
• MATLAB release: MATLAB 6.5 (R13)
• Other Files: gaborfilter.m, ; gaborfilter2.m, ; gaborfilter1.m

[mana sh]

thx,very complete!!

[robert kelly]

I need this for my project very very much.You do it well:))

[khaled sultan]

thnka

[ali adhami]

very powerfull!

[Jesmin Khan]

 

[Viara Van Raad]

Usually 2D design of Gabor filters require DESIGN in 2D Frequency ( because it can easily get out of boounds!). This is related to several issues:
a) not obeying the Nyquist criteria
b) phase distortions
c) not forming a '' frame'' see 10 lectures on wavelets
d) mack up in 2D frequencies
and some others. The design in space is naive.

[Daniel Garcia]

It is good

[Alex Leykin]

The normalization doesn't work. The repsonse jumps out of bounds at pi/2

[Natalia Zabrydowa]

thank you:)

[Luigi Rosa]

Excellent work. In order to improve filtering performances a Recursive Gabor filtering for 1D and 2D signals is required.

For more information please visit:
 
http://utenti.lycos.it/matlab/gabor.htm

[Pablo Suau]

It doesn't work when using pi/2

[abdel oranov]

les deux filtre ne sont pas symetrique.
pour verifier tu fais sum(G1(:)) tu va trouver que ce n'est pas tjr symetrique;

[adek yudi]

after I tried, I think it's great...!!!

[ahmad vazvani]

 

[gopal krishnan]

 

[Basabdatta Bhattacharya]

 

[Fiona Yu]

The mask matrix is excellent in approximation to the Gaussian envelope.

[Peng Zhangping]

i want to process the image of fingerprints,i hope this can help me to enhance the image.

[yu qian]

 

[wang yue]

 

[Alok Whig]

Q1. What is the difference between GaborFilter,
    GaborFilter1 and GaborFilter2 ?

Q2. Is R13 realease same as MATLAB version 7.0 ?

I tried the files.They work fine.

[A.H. S]

A Good Job done

[Liu Xianru]

It is very good and suit for new researchers!
Thank you !

[wise wise]

"Gabor filters are used mostly in shape detectin and feature extractin in image processing"

Can somebody give me some help on how to use gabor filter for fingerprint image feature extraction?

thanks..

[Chenna Krishna Varri]

 

[saratchandra k]

I found this little description very useful. Wee bit'o more info about the cortical cell study .. or maybe where I can find it would be useful. And yeah im working on fingerprints and would like to get more info in that regard

[yunchu ZHANG]

This helps me a lot!

[sriram pothuri]

 

[vijay anandh]

 

[Deepti Singh]

Cn anyone tell me how to calculate optimal sx,sy,theta and f for an image.so that this function cn be used irrespective of any image.How to implement it i mean how to use the output G and gabout.Thx in advance.urgetntly in need of reply

[Hyeong-yong Jeon]

good!

[he yi]

very good,I once program a c++ version about gabor filters. now I find this code and use it to verify mine. It is very convenient and thanks for u.

[Sam Darvishi]

 

[Piyorot Khongchuay]

cool

[Engy Cruel Heart]

 

[deepak singh]

great work

[cintia monti]

 

[Piyorot Khongchuay]

Cool

[Bobby Jan]

Excellent. Has some one tried recursive Gabor filtering & its usefulness? Can some one share?

[Mayank Raj]

Great

[Udai Kiran]

Cool

[bendahmane zakaria]

 

[hamed kowsari]

 

[Weijun Zhao]

Thanks, I have been searching for it.

[Dirkjan Krijnders]

Functionality is good, but code does not depends on any toolbox and documentation is not in standard matlab format.

[hari bashkarraj]

very nice

[Makoto Sanada]

I am reading the gaborfilter1.m (version2), and I think there is a mistake.
In the source codes, there is a code line to retrive imaginary parts of filters as imag(G).
However, the math equation of G is originally calculating only real responses (cos). There is no jsin or exp(j...).
Don't you need imaginary responses?

[hamed kowsari]

 

[J. Colineau]

The output seems to be the modulus of the complex response to your filter. In many cases, the interesting part is the real component, and not the modulus, which is a non-linear operation !

[T G]

i think there is a mistake in this code. because the results shown in this link http://matlabserver.cs.rug.nl/edgedetectionweb/web/index.html are obtained by using the equation in this link, http://matlabserver.cs.rug.nl/edgedetectionweb/web/edgedetection_params.html

but unfortunately, these results are not as same as yours.

isn't it???

please, tell me if i'm wrong.
thanks a lot..

[paulhac ludo]

I don't know if there is a mistake in this code. In fact the imaginary part is always null but it is normal if we look the formula used. In the formula there is not the imaginary part.
The general gabor formula has an imaginary part, but usually , when I read article, there is not this imaginary part and I don't know why.
Is there someone to answer ???

I implement gabor with the imaginary part and when I try with this link http://matlabserver.cs.rug.nl/edgedetectionweb/web/index.html I don't find the same things. But the result depends how we set parameters.

[Jyotirmoy Banerjee]

The formula used in this code doesn't have parameters like aspect ratio and phase. so it is not fair to compare the results with some other code. All depends on the parameters you set.

[hamed nozari]

 

[Liang Zhao]

 

[ujjal bhowmik]

 

[Emin Orhan]

The discrepancy between the results obtained by filtering with this implementation and the with the one on the matlabserver.cs.rug.nl is, I think, related to the size of the filter, G, instead of fix(Sx) (and fix(Sy)), try something like fix(3*Sx) etc.-i.e.enlarge the size of the filter- and the code works just fine (in corformity with matlabserver.cs.rug.nl), nothing wrong with the code.

[au diesel]

thx

[lorenzo rossi]

Why I have this error?
Function 'conv2' is not defined for values of class 'double' and attributes 'full 3d real'.

[Selvan Selvanidhyananthan]

Gabor filter is a very interesting topic in wavelets.

[Protik Maitra]

A few images with corresponding parameters would have helped understand this better.

[Ratnakar Dash]

 

[Feng Liu]

very good!

[Richa Agarwal]

Its very good.

[Jose Armando Fernández Gallego]

Muy buen Codigo !

[ksibi amel]

good

[Hedieh Sajedi]

 

[jun wu]

thanks for your Gabor filter.

[Abd Elghany mohamed]

Aslamo alekm
are you hove this code using IDL programming

[jimmy wang]

So helpful!TKS

[Pushkin Alexander]

Ican't fix "Undefined function or method 'conv2' for input arguments of type 'double' and attributes 'full 3d real'." Please somebody tell how fix it by "reshape". Thanks

[AKROUT Belhassen]

good job

[vishal wankhede]

Very efficient

[sandeep gupta]

it is efficiently working

[Geovanny Giorgana]

Hi all, I got the same error: Function 'conv2' is not defined for values of class 'double' and attributes 'full 3d real'.

Can someone explain me how to solve it. Thank you.

[mohammad poshideh]

 

[mohammad poshideh]

 

[akshay aggarwal]

@Geovanny Giorgana: the filter works only for a 2-D immage. Try checking the size of the input image.

[vinayak jagzap]

i m working on gabor filter
will u please send me the details
n if possible the code for fingerprint image
enhancement using it

[sidd singh]

nice

[Anton]

By looking over the code and the description, it seems the filters are being crated in the frequency domain and then applied in the spatial domain. Please correct me if I am wrong but this is WRONG. There are two RIGHT approaches. The first is that one needs to take the inverse FT of the filter and then convolve it with the image. The second it that one needs to convert the image into the frequency domain, multiply the spectra and then take the inverse of the result.

[ganesh kumar]

can u just brief me on the parameters of the filter?On what basis do i select the parameter values??

[Varsha Mhaske]

 

[kevin]