Content-aware image rotation

摘要

According to implementations of this disclosure, image content is rotated in a content-aware fashion. In one implementation, a mesh is formed over an image and image lines in the image content are identified. The image is warped using an energy function that rotates a subset of the lines a predetermined rotation angle, while rotating other lines by an angle other than the predetermined rotation angle. In one example, lines that are intended to be horizontal or vertical after correcting are rotated by a rotation angle that will make them horizontal or vertical, whereas oblique lines are rotated by an angle other than the rotation angle.

主权项

1. A system comprising:
one or more processors; memory, communicatively coupled to the one or more processors, storing executable instructions that, when executed by the one or more processors, configure the one or more processors to perform acts comprising:
receiving an input image containing original image content, the original image content including a pre-existing rotation about a pre-existing rotation angle;identifying lines corresponding to linear features in the image content;fitting a mesh to the image content, the mesh having a mesh boundary corresponding to a boundary of the image content;grouping the lines in a plurality of groupings comprising one or more oblique groupings and at least one of a horizontal grouping or a vertical grouping;optimizing the mesh according to an energy function to define an optimized mesh, the energy function comprising:
a rotation preservation term encouraging preservation of a desired rotation of the image content to counteract for the pre-existing rotation about the pre-existing rotation angle;a line preservation term defining a relationship between the lines and vertexes of the mesh;a shape preservation term, anda boundary preservation term to constrain the optimized mesh to the boundary of the image content; anddeforming the image content according to the optimized mesh to produce a corrected image comprising corrected image content, the corrected image content including a corrected rotation about a corrected rotation angle, wherein the corrected rotation angle is less than the pre-existing rotation angle.