what is gabor filter and how it works (MATLAB)

hello all,

i am doing my final year project on face detection system using matlab.
i need some help in understanding the working of gabor filter.

please provide some help for this, and give me the code for this in matlab.

Thanx in advance for kind help.

Regards,
varun

Gabor filters are defined by harmonic functions modulated by a Gaussian distribution. As an example, in two dimensions and using a polar coordinate system with coordinates and :

Gabor filters bear some similarity to Fourier filters, but (by the Gaussian damping terms) are limited to certain frequency bands (passband filter). With a judicious choice of frequencies, e.g. by octaves (viz. by successive factors of 2), a succession of Gabor filters can be assimilated to a wavelet transform, and do an excellent job in image or information compaction.

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Gabor Wavelet Filter
The use of the 2D Gabor filter in computer vision was introduced by Daugman in the late 1980s. Since that time it has been used in many computer vision applications including image compression , edge detection , texture analysis , object recognition and facial recognition.The general form for a complex-valued 2D Gabor function is a planar wave attenuated by a Gaussian envelope:

Thanku sir for ur kind notice to my problem. I am new in image processing field, so can u please elaborate gabor filter in some simple language. and please provide some study material about this.

Regards,
varun

check these
Systems Biophysics - Research - Gabor Filter
http://www.umiacs.umd.edu/~ramani/cmsc426/Matlab_Lecture8.pdf
http://mplab.ucsd.edu/tutorials/gabor.pdf

i need the clear details of the gabor filter inputs and various variable in it ..
pls tell me