N=512; A=zeros(N,N); B=zeros(N,N); for I=1:1:256 J=1:1:256 ImageNum=double(Image(I,J,1)); A(I,J)=ImageNum/255; B(I,J)=0; end end figure; imshow(A); pi=3.1415926; for I=1:1:N for J=1:1:N R=rand(1,1);%生成一個元素在0,1之間均勻分布的隨機矩陣R B(I,J)=A(I,J)*sin(R*2*pi);%平滑函數(shù)的傅里葉變換譜 A(I,J)=A(I,J)*cos(R*2*pi); F(I,J)=A(I,J)+j*B(I,J); end End%限制振幅的動態(tài)范圍,提高編碼的精度 F=fft2(F);%作二維快速傅里葉變換FFT Max=max(max(abs(F))); F=F/Max; A=real(F); B=imag(F); aIpha=0.5;%定義載波參數(shù)aIpha for I=1:1:N for J=1:1:N Xcos=(J-1)/127; A1(I,J)=cos(2*pi*aIpha*Xcos); B1(I,J)=sin(2*pi*aIpha*Xcos); end end%全息圖數(shù)據(jù)區(qū) for I=1:1:N for J=1:1:N HoIodata(I,J)=0.5+0.5*(A(I,J)*A1(I,J)+B(I,J)*B1(I,J)); end End M=512;N=512;%定義全息圖的大小 Hologram=zeros(M,M); S=M/N;%定義每個抽樣單元大小 for I=1:1:N for J=1:1:N Xa=(J-1)*S+1; Xb=J*S; Ya=(I-1)*S+1; Yb=I*S; for Ix=Xa:1:Xb for Iy=Ya:1:Yb HoIogram(Iy,Ix)=HoIodata(I,J); end end end end Max=max(max(HoIogram)); HoIogram=HoIogram/Max; figure; imshow(HoIogram); %以下是用matlab分別計算函數(shù)各抽樣點的傅里葉變換譜的幅角與模,并對各點的模歸一化 object=fft2(HoIogram); object=fftshift(object);%用matlab中的移譜函數(shù)fftshift( )將頻譜的低頻成分移到中心,以避免再現(xiàn)時像分散在邊緣 object=abs(object); object=1000*object/max(max(object)); figure; imshow(object);