Learn more about Image Processing Toolbox

imrotate - Rotate image

Syntax

B = imrotate(A,angle)
B = imrotate(A,angle,method)
B = imrotate(A,angle,method,bbox)

Description

B = imrotate(A,angle) rotates image A by angle degrees in a counterclockwise direction around its center point. To rotate the image clockwise, specify a negative value for angle. imrotate makes the output image B large enough to contain the entire rotated image. imrotate uses nearest neighbor interpolation, setting the values of pixels in B that are outside the rotated image to 0 (zero).

B = imrotate(A,angle,method) rotates image A, using the interpolation method specified by method. method is a text string that can have one of these values. The default value is enclosed in braces ({}).

Value	Description
{'nearest'}	Nearest-neighbor interpolation
'bilinear'	Bilinear interpolation
'bicubic'	Bicubic interpolation Note   Bicubic interpolation can produce pixel values outside the original range.

B = imrotate(A,angle,method,bbox) rotates image A, where bbox specifies the size of the returned image. bbox is a text string that can have one of the following values. The default value is enclosed in braces ({}).

Value	Description
'crop'	Make output image B the same size as the input image A, cropping the rotated image to fit
{'loose'}	Make output image B large enough to contain the entire rotated image. B is generally larger than A.

Class Support

The input image can be numeric or logical. The output image is of the same class as the input image.

Performance Note

This function may take advantage of hardware optimization for data types uint8, uint16, and single to run faster.

Examples

Read a solar spectra image, stored in FITS format, and rotate the image to bring it into horizontal alignment. A rotation of -1 degree is all that is required.

I = fitsread('solarspectra.fts');
I = mat2gray(I);
J = imrotate(I,-1,'bilinear','crop');
figure, imshow(I)
figure, imshow(J)

See Also

imcrop, imresize, imtransform, tformarray

imroi

imsave

© 1984-2009- The MathWorks, Inc.    -   Site Help   -   Patents   -   Trademarks   -   Privacy Policy   -   Preventing Piracy   -   RSS