Rendering for 3D Light Field composed of 360° Images

Abstract

Light Field (LF) is very simple in that it creates views by combining pixels from images. Especially, 3D LF considers light rays passing through a line, not a plane, so it is easy to captures light rays. This paper proposes a LF rendering method in a 3D LF composed of 360° images, which supports maximum field of view. Existing 3D LF acquires light rays with a general camera such as an action camera or a DSLR camera, and the conventional 3D LF rendering takes this into consideration. If the 3D LF rendering method is applied to the 3D LF composed of 360° images, unnatural views are rendered. To cope with this problem, this paper proposes two rendering schemes. First is warping, which is used to create views from equirectangular 360° images. It serves to straighten curved objects in a equirectangular image. Second is light ray selection considering vertical incident angle (LRS-VA). The relationship between light rays and viewpoint motion depends on vertical incident angle, but the conventional 3D LF rendering does not take this into account. By considering this relationship, LRS-VA renders the top and bottom pole views more natural. In addition, LF rendering requires very fast operation speed, and this paper verifies the real-time operation of the proposed method through GPU implementation.