(PECL imagick 2.0.0)
Imagick::flipImage — Creates a vertical mirror image
Creates a vertical mirror image by reflecting the pixels around the central x-axis.
成功时返回 TRUE。
错误时抛出 ImagickException。
Lee (2012-06-06 20:12:50)
They mean, "Creates a horizontal mirror image by reflecting the pixels around the central y-axis."