%?Table?3.1?OSH.m?:?m-file?for?illustrating?optical?scanning?holography.
%------------------------------------------------------
%?OSH.m
%?Adapted?from?“Contemporary?Optical?Image?Processing?with?MATLAB“
%?by?Ting-Chung?Poon?and?Partha?Banerjee?Table?7.2
%?Pages?222-223?Elsevier?（2001）.
clear?all
%%Reading?input?bitmap?file
I=imread（‘lena.jpg‘）;
I=I（::1）;
figure（1）%displaying?input
colormap（gray（255））;
image（I）
title（‘Original?image‘）
axis?off
pause
%%Creating?OTFosh?with?SIGMA=z/2*k0?（Eq.（3.5-1a））
ROWS=512;
COLS=512;
sigma=2.0;?%not?necessary?to?scale
%kxky?are?spatial?frequencies
ky=-12.8;
for?r=1:COLS
kx=-12.8;
for?c=1:ROWS
OTFosh（rc）=exp（-j*sigma*kx*kx-j*sigma*ky*ky）;
kx=kx+.1;
end
ky=ky+.1;
end
max1=max（OTFosh）;
max2=max（max1）;
scale=1.0/max2;
OTFosh=OTFosh.*scale;
%Recording?hologram
%?Taking?Fourier?transform?of?I
FI=fft2（I）;
FI=fftshift（FI）;
max1=max（FI）;
max2=max（max1）;
scale=1.0/max2;
FI=FI.*scale;
%?FH?is?the?recorded?hologram?in?Fourier?domain
FH=FI.*OTFosh;
H=ifft2（FH）;
max1=max（H）;
max2=max（max1）;
scale=1.0/max2
H=H.*scale;
figure（1）
colormap（gray（255））;
%Displaying?the?real?part?becomes?sine-FZP?hologram
%?Eq.?（3.5-8a）
image（2.5*real（512*H））;
title（‘Sine-FZP?hologram