Easiest way to rotate by 90 degrees an image using OpenCV?

c++ image opencv rotation
Ben H picture Ben H · Feb 14, 2010 · Viewed 101.1k times · Source

What is the best way (in c/c++) to rotate an IplImage/cv::Mat by 90 degrees? I would assume that there must be something better than transforming it using a matrix, but I can't seem to find anything other than that in the API and online.

Answer

Morris Franken picture Morris Franken · Jun 23, 2017

As of OpenCV3.2, life just got a bit easier, you can now rotate an image in a single line of code:

cv::rotate(image, image, cv::ROTATE_90_CLOCKWISE);

For the direction you can choose any of the following:

ROTATE_90_CLOCKWISE
ROTATE_180
ROTATE_90_COUNTERCLOCKWISE

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