Imagick::setImageOrientation

orrd101 at yahoo dot com (2013-02-20 21:20:36)

Be aware that Imagick::setImageOrientation() doesn't actually rotate the image, it just changes the EXIF rotation info that will be saved with the image. In some cases that may be what you want to do, but if you're trying to rotate an image, this probably isn't the way you want to do it. The problem with relying on the EXIF rotation info is that many web browsers ignore and some image viewing software ignore the EXIF information and don't auto-rotate it automatically. This function is best used to correct EXIF rotation information just before saving an image.
To actually rotate an image, use Imagick::rotateImage().
And then maybe use this function to save the correct EXIF orientation data. For example: $image->setImageOrientation(imagick::ORIENTATION_TOPLEFT);