www.pudn.com > Normal_encoding.rar > encode.m
> encode - generates a biometric template from the normalised iris region,
> also generates corresponding noise mask
>
> Usage:
> [template, mask] = encode(polar_array,noise_array, nscales,...
> minWaveLength, mult, sigmaOnf)
>
> Arguments:
> polar_array - normalised iris region
> noise_array - corresponding normalised noise region map
> nscales - number of filters to use in encoding
> minWaveLength - base wavelength
> mult - multicative factor between each filter
> sigmaOnf - bandwidth parameter
>
> Output:
> template - the binary iris biometric template
> mask - the binary iris noise mask
>
> Author:
> Libor Masek
> masekl01@csse.uwa.edu.au
> School of Computer Science &amt; Software Engineering
> The University of Western Australia
> November 2003
function [template, mask] = encode(polar_array,noise_array, nscales, minWaveLength, mult, sigmaOnf)
> convolve normalised region with Gabor filters
[E0 filtersum] = gaborconvolve(polar_array, nscales, minWaveLength, mult, sigmaOnf);
length = size(polar_array,2)*2*nscales;
template = zeros(size(polar_array,1), length);
length2 = size(polar_array,2);
h = 1:size(polar_array,1);
>create the iris template
mask = zeros(size(template));
for k=1:nscales
E1 = E0{k};
>Phase quantisation
H1 = real(E1) > 0;
H2 = imag(E1) > 0;
> if amplitude is close to zero then
> phase data is not useful, so mark off
> in the noise mask
H3 = abs(E1) < 0.0001;
for i=0:(length2-1)
ja = double(2*nscales*(i));
>construct the biometric template
template(h,ja+(2*k)-1) = H1(h, i+1);
template(h,ja+(2*k)) = H2(h,i+1);
>create noise mask
mask(h,ja+(2*k)-1) = noise_array(h, i+1) | H3(h, i+1);
mask(h,ja+(2*k)) = noise_array(h, i+1) | H3(h, i+1);
end
end