Content-Aware Rotation

We present an image editing tool called Content-Aware Rotation. Casually shot photos can appear tilted, and are often corrected by rotation and cropping. This trivial so-lution may remove desired content and hurt image integri-ty. Instead of doing rigid rotation, we propose a warping method that creates the perception of rotation and avoids cropping. Human vision studies suggest that the perception of rotation is mainly due to horizontal/vertical lines. We de-sign an optimization-based method that preserves the rota-tion of horizontal/vertical lines, maintains the completeness of the image content, and reduces the warping distortion. An efficient algorithm is developed to address the challeng-ing optimization. We demonstrate our content-aware rota-tion method on a variety of practical cases. 1