How do I make the reconstructed light image more clear with less noise?

Question

Diptayan Dasgupta 2021-5-13

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/829113-how-do-i-make-the-reconstructed-light-image-more-clear-with-less-noise

评论： Diptayan Dasgupta 2021-5-13

I just want to make the reconstructed light image more clear and more visible if its possible. That's the code I used. The above image is the source.

clear all, close all;
Ii=imread('1 A.png');% 256*256 pixels 8bit
figure; imshow(Ii);
title('Object pattern')
axis off
Ii=double(Ii);
Ii=Ii(:,:,1);
PH=rand([256,256]);
Ii=Ii.*exp(2i*pi*PH); % add a random phase on the object
M=512;
I=zeros(512);
I(128:383,128:383)=Ii; % zero padding
z=1; %(cm, distance) PLEASE CHANGE THE DISTANCE TO 1, 5, 15, ETC.
w=6500*10^-8; %(cm, wavelength)
delta=0.005; % cm, pixel size 50um
r=1:M;
c=1:M;
[C, R]=meshgrid(c, r);
% Forward propagation (650nm)
p=exp(-2i*pi*z.*((1/w)^2-(1/M/delta)^2.*(C-M/2-1).^2-(1/M/delta)^2.*(R-M/2-1).^2).^0.5);
A0=fftshift(ifft2(fftshift(I)));
Az=A0.*p;
E=fftshift(fft2(fftshift(Az))); % 1st order of the hologram
% Reconstruction (650nm)
p=exp(-2i*pi*(-z).*((1/w)^2-(1/M/delta)^2.*(C-M/2-1).^2-(1/M/delta)^2.*(R-M/2-1).^2).^0.5);
A1=fftshift(ifft2(fftshift(E)));
Az1=A1.*p;
R1=fftshift(fft2(fftshift(Az1)));
R1=(abs(R1)).^2;
figure; imshow(R1/max(max(R1)));
title('Reconstructed image(650nm)')
axis off
% Reconstruction (450nm~650nm)
dw=50;
IMA=zeros(512,512);
for g=0:40;
w2=(20000-dw*g)*10^-8; % reconstruction wavelength
E2=E.*exp(2i*pi*sind(10)*(w-w2)/w/w2.*R*delta);
% phase mismatch due to the wavelength shift
p=exp(-2i*pi*(-z).*((1/w2)^2-(1/M/delta)^2.*(C-M/2-1).^2-(1/M/delta)^2.*(R-M/2-1).^2).^0.5);
Az2=ifft2(fftshift(E2)).*(fftshift(p));
R2=fftshift(fft2(Az2));
R=(abs(R2)).^2; % summation of all wavelengths
IMA=IMA+R2;
end
IMA=IMA/max(max(IMA));
figure; imshow(IMA)
title('Reconstructed image(white light)')
axis off