Efficient propagation of sparse edits on 360 panoramas

We present an efficient method to propagate sparse user edits indicated by strokes on 360 panoramas. Our algorithm first projects each equirectangular pixel to its corresponding position on a 3D unit sphere, so each pixel can be characterized by a feature vector consisting of its 3D coordinates and RGB color values. We formulate edit propagation as an optimization problem that aims to satisfy the user edit constraints while preserving the manifold structure of the image at the same time. To solve the problem using a linear system efficiently, we first construct the K-D tree structure in the feature space to cluster pixels. Then we optimize the manifold structure where both the number of nearest neighbors and their corresponding weights are determined by the feature distributions. We further apply a multiresolution strategy to speedup the edit propagation. Our method is the first to perform interactive edit propagation on 360 panoramas. Experiments show that our method is able to generate seam-free and visually pleasing results, and users can receive instant feedback during interactive editing