rgb=imread('f:\image\9.jpg'); %读入一幅图像
fR=rgb(:,:,1); %
fG=rgb(:,:,2); %三种分量RGB的分解
fB=rgb(:,:,3); %
figure,imshow(fB); %显示Blue分量
rgb_img=cat(3,fR,fG,fB); %三个分量组合
figure,imshow(rgb) %显示原图
figure,imshow(rgb_img); %显示合成图
%rgbcube%
function rgbcube(fR, fG, fB)
%RGBCUBE Displays an RGB cube on the MATLAB desktop.
% RGBCUBE(fR, fG, fB) displays an RGB color cube, viewed from point
% (fR, fG, fB). With no input arguments, RGBCUBE uses (10, 10, 4)
% as the default viewing coordinates. To view individual color
% planes, use the following viewing coordinates, where the first
% color in the sequence is the closest to the viewing axis, and the
% other colors are as seen from that axis, proceeding to the right
% right (or above), and then moving clockwise.
%
% -------------------------------------------------
% COLOR PLANE (fR, fG, fB)
% -------------------------------------------------
% Blue-Magenta-White-Cyan ( 0, 0, 10)
% Red-Yellow-White-Magenta ( 10, 0, 0)
% Green-Cyan-White-Yellow ( 0, 10, 0)
% Black-Red-Magenta-Blue ( 0, -10, 0)
% Black-Blue-Cyan-Green (-10, 0, 0)
% Black-Red-Yellow-Green ( 0, 0, -10)
%
% Copyright 2002-2004 R. C. Gonzalez, R. E. Woods, & S. L. Eddins