Rendering Layered Depth Images

In this paper we present an e cient image based rendering system that renders multiple frames per second on a PC. Our method performs warping from an intermediate representation called a layered depth image (LDI). An LDI is a view of the scene from a single input camera view, but with multiple pixels along each line of sight. When n input images are preprocessed to create a single LDI, the size of the representation grows linearly only with the observed depth complexity in the n images, instead of linearly with n. Moreover, because the LDI data are represented in a single image coordinate system, McMillan's warp ordering algorithm can be successfully adapted. As a result, pixels are drawn in the output image in back to front order. No z-bu er is required, so alpha-compositing can be done e ciently without depth sorting. This makes splatting an e cient solution to the resampling problem.