flip and rotate a color image in MATLAB

How do I flip a color image (RGB) in MATLAB? T开发者_C百科he fliplr does not seem to work without losing the color contents, as it only deals with 2D.

As well, the imrotate may not rotate color images.

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The function flipdim will work for N-D matrices, whereas the functions flipud and fliplr only work for 2-D matrices:

img = imread('peppers.png');     %# Load a sample image
imgMirror = flipdim(img,2);      %# Flips the columns, making a mirror image
imgUpsideDown = flipdim(img,1);  %# Flips the rows, making an upside-down image

NOTE: In more recent versions of MATLAB (R2013b and newer), the function flip is now recommended instead of flipdim.

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An example:

I = imread('onion.png');
I2 = I(:,end:-1:1,:);           %# horizontal flip
I3 = I(end:-1:1,:,:);           %# vertical flip
I4 = I(end:-1:1,end:-1:1,:);    %# horizontal+vertical flip

subplot(2,2,1), imshow(I)
subplot(2,2,2), imshow(I2)
subplot(2,2,3), imshow(I3)
subplot(2,2,4), imshow(I4)

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imrotate rotates color images B = IMROTATE(A,ANGLE) rotates image A by ANGLE degrees in a counterclockwise direction around its center point.

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I know it is late, but since flipdim is now depreciated, other answers are not valid anymore. You could use flip, or do it in other, smart way:

I = imread('onion.png');

% flip left-right, or up-down:

Iflipud = flip(I, 1)
Ifliplr = flip(I, 2)

% or:
Iflipud = I(size(I,1):-1:1,:,:);
Ifliplr = I(:,size(I,1):-1:1,:);

% flip both left-right, and up-down, stupid way:
Iflipboth = I(size(I,1):-1:1,size(I,1):-1:1,:);

% flip both left-right, and up-down, smart way:):
Iflipboth = imrotate(I, 180)

As already pointed, imrotate deals with color images as well as with greyscale.