RGB 与 (RGB转 YCbCr再转为 RGB)的图像 不可逆,能够从 矩阵的逆运算看出来。
附上 matlab 代码:
clc,clear; Source=imread('1.jpg');%读入原始RGB图像 figure(1); subplot(1,2,1); imshow(Source):title('original image');%显示图像 [r c d]=size(Source);%计算图像大小 %------计算红色分量并显示分解图------% R(:,:,1)=Source(:,:,1); R(:,:,2)=zeros(r,c); R(:,:,3)=zeros(r,c); R=uint8(R); whos; figure(2); subplot(1,3,1); imshow(R) title('Red Component'); %-------计算绿色分量并显示分解图-------% G(:,:,2)=Source(:,:,2); G(:,:,1)=zeros(r,c); G(:,:,3)=zeros(r,c); G=uint8(G); figure(2); subplot(1,3,2); imshow(G) title('Green Component'); %--------计算蓝色分量并显示分解图-------% B(:,:,3)=Source(:,:,3); B(:,:,1)=zeros(r,c); B(:,:,2)=zeros(r,c); B=uint8(B); figure(2); subplot(1,3,3) imshow(B) title('Blue Component'); %------------合成-------------% Comp(:,:,1)=R(:,:,1); Comp(:,:,2)=G(:,:,2); Comp(:,:,3)=B(:,:,3); figure(5); subplot(1,2,2); imshow(Comp):title('composition image'); Y=0.213*R+0.715*G+0.072*B; Cb=0.511*B-0.117*R-0.394*G+128; Cr=0.511*R-0.464*G-0.047*B+128; %red=Y+1.402*(Cr-128); %green=Y-0.34414*(Cb-128)-0.71414*(Cr-128); %blue=Y+1.772*(Cb-128); red = 1.164*(Y-16)+1.793*(Cr-128); green = 1.164*(Y-16)-0.534*(Cr-128)-0.213*(Cb-128); blue =1.164*(Y-16)+2.115*(Cb-128); Comp2(:,:,1)=red(:,:,1); Comp2(:,:,2)=green(:,:,2); Comp2(:,:,3)=blue(:,:,3); Comp5(:,:,1)=Y(:,:,1); Comp5(:,:,2)=Cb(:,:,2); Comp5(:,:,3)=Cr(:,:,3); figure(5);imshow(Comp5);title('显示11YCBcr'); figure(1);subplot(1,2,2);imshow(Comp2);title('RGB转换为YCrCb后又转换为RGB的图像'); RD=R(:,:,1)-red(:,:,1); GD=G(:,:,2)-green(:,:,2); BD=B(:,:,3)-blue(:,:,3); figure(4);subplot(1,3,1);imshow(RD);title('红色分量差异'); subplot(1,3,2);imshow(GD);title('绿色分量差异'); subplot(1,3,3);imshow(BD);title('蓝色分量差异');