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7b4139b | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 | function apod = apodization(distance,aperture,window)
%-- Function which assigns different apodization to a set of pixels and elements
%-- Function prototype: apodization = apodization(distance,aperture,window)
%-- Authors: Alfonso Rodriguez-Molares (alfonso.r.molares@ntnu.no)
%-- Olivier Bernard (olivier.bernard@creatis.insa-lyon.fr)
%-- $Date: 2016/03/01 $
switch(window)
case 'none'
apod = ones(size(distance));
case 'boxcar'
apod = double(distance<=aperture/2);
case 'hanning'
apod = double(distance<=aperture/2).*(0.5 + 0.5*cos(2*pi*distance./aperture));
case 'hamming'
apod = double(distance<=aperture/2).*(0.53836 + 0.46164*cos(2*pi*distance./aperture));
case 'tukey25'
roll=0.25;
apod =(distance<(aperture/2*(1-roll))) + (distance>(aperture/2*(1-roll))).*(distance<(aperture/2)).*0.5.*(1+cos(2*pi/roll*(distance./aperture-roll/2-1/2)));
case 'tukey50'
roll=0.5;
apod=(distance<(aperture/2*(1-roll))) + (distance>(aperture/2*(1-roll))).*(distance<(aperture/2)).*0.5.*(1+cos(2*pi/roll*(distance./aperture-roll/2-1/2)));
case 'tukey75'
roll=0.75;
apod=(distance<(aperture/2*(1-roll))) + (distance>(aperture/2*(1-roll))).*(distance<(aperture/2)).*0.5.*(1+cos(2*pi/roll*(distance./aperture-roll/2-1/2)));
otherwise
error('Unknown window type. Known types are: boxcar, hamming, hanning, tukey25, tukey50, tukey75.');
end
end
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