数字图像处理实验(8).doc

实验4报告学 校：海南大学班 级：信息安全（1）班姓 名：谯红亮学 号：20091616310019指导老师：姚孝明成 绩: 实验目的：通过实验熟悉并掌握频域内底通滤波，带通滤波，高通滤波的基本概念和方法。实验内容：1。低通滤波的概念与方法：熟悉，掌握lpfilter()的使用方法。掌握频域内其相关性质的可视化方法(mesh()函数的使用方法)2带通滤波的概念与方法：通过可视化过程，比较其滤波器的特征差异：3高通滤波的概念与方法：熟悉，掌握hpfilter()的使用方法。通过可视化过程，比较其滤波器的特征差异实验步骤：A=fft2(pout);a=real(A);b=imag(A);实数，虚数c=abs(A);绝对值imshow(c,);figure,imshow(fftshift(c),); figure,imshow(fftshift(log(c),); figure,imshow(log10(c),); 实部做实轴，虚部做虚轴，figure,plot(a,b); h=lpfilter(ideal,3,3,10);A1=filter2(h,pout,same);figure,imshow(A1,); x,y=meshgrid(1:3);figure,mesh(x,y,h);h1=lpfilter(btw,3,3,10);figure,mesh(x,y,h1);h2=lpfilter(gaussian,3,3,10);figure,mesh(x,y,h2);x,y=meshgrid(1:20);h=lpfilter(ideal,20,20,10);figure,mesh(x,y,h);figure,mesh(x,y,fftshift(h);h1=lpfilter(btw,20,20,5);figure,mesh(x,y,fftshift(h1);h1=lpfilter(btw,20,20,10);figure,mesh(x,y,fftshift(h1);h3=hpfilter(ideal,20,20,5);figure,mesh(x,y,fftshift(h3);figure,mesh(x,y,(h3);h=hpfilter(ideal,20,20,5);figure,mesh(x,y,(h);figure,mesh(x,y,(h3);L1=lpfilter(gaussian,291,240,10);B1=A.*L1;figure,imshow(real(B1),);figure,imshow(uint8(C1);C1=ifft(B1);负列变换的逆变换figure,imshow(uint8(C1);C1=real(C1);figure,imshow(real(C1),);figure,imshow(uint8(C1);C1=ifft2(B1); figure,imshow(uint8(C1);L2=lpfilter(gaussian,291,240,2); B2=A.*L2; C2=ifft2(B2); figure,imshow(uint8(C2);H=lpfilter(gaussian,291,240,10); B3=A.*H; C3=ifft2(B3);figure,imshow(uint8(C3);figure,imshow(C3,);H1=lpfilter(gaussian,291,240,5); B4=A.*H1; C4=ifft2(B4); figure,imshow(C4,);figure,imshow(pout);LP=lpfilter(btw,291,240,5); HP=lpfilter(btw,291,240,5); D1=A.*HP; D2=A.*LP; D=D1+D2; E=ifft2(D);figure,subplot(121),imshow(pout);subplot(122),imshow(E);figure,subplot(121),imshow(pout);subplot(122),imshow(E,);F