ch4_3_5利用radon函数和iradon函数构造一个简单图像的投影并重建图像.m

%利用radon函数和iradon函数构造一个简单图像的投影并重建图像%产生256个灰度等级的大脑图P = phantom(256);imshow(P)%计算3个不同部分的大脑图的Radon变换theta1 = 0:10:170;[R1,xp] = radon(P,theta1);theta2 = 0:5:175;[R2,xp] = radon(P,theta2);theta3 = 0:2:178;[R3,xp] = radon(P,theta3);%显示Shepp-Logan大脑幻影图的有90条投影光束的Radon变换图形figure, imagesc(theta3,xp,R3); colormap(hot); colorbarxlabel('\theta'); ylabel('x\prime');%利用R1、R2和R3分别进行Shepp-Logan大脑幻影图的重构I1 = iradon(R1,10);I2 = iradon(R2,5);I3 = iradon(R3,2);imshow(I1)figure, imshow(I2)figure, imshow(I3)