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We describe an image based rendering approach that generalizes many image based rendering algorithms currently in use including light field rendering and view-dependent texture mapping. In particular it allows for lumigraph style rendering from a set of input cameras that are not restricted to a plane or to any specific manifold. In the case of regular and planar input camera positions, our algorithm reduces to a typical lumigraph approach. In the case of fewer cameras and good approximate geometry, our algorithm behaves like view-dependent texture mapping. Our algorithm achieves this flexibility because it is designed to meet a set of desirable goals that we describe. We demonstrate this flexibility with a variety of examples.

In this paper we present a set of efficient image based rendering methods capable of rendering multiple frames per second on a PC. The first method warps Sprites with Depth representing smooth surfaces without the gaps found in other techniques. A second method for more general scenes 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. The size of the representation grows only linearly with the observed depth complexity in the scene. 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 backto-front order. No z-buffer is required, so alpha-compositing can be done efficiently without depth sorting. This makes splatting an efficient solution to the resampling problem.

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In this paper, we describe an efficient image-based approach to computing and shading visual hulls from silhouette image data. Our algorithm takes advantage of epipolar geometry and incremental computation to achieve a constant rendering cost per rendered pixel. It does not suffer from the computation complexity, limited resolution, or quantization artifacts of previous volumetric approaches. We demonstrate the use of this algorithm in a real-time virtualized reality application running off a small number of video streams.

Surface geometry is often modeled with irregular triangle meshes. The process of remeshing refers to approximating such geometry using a mesh with (semi)-regular connectivity, which has advantages for many graphics applications. However, current techniques for remeshing arbitrary surfaces create only semi-regular meshes. The original mesh is typically decomposed into a set of disk-like charts, onto which the geometry is parametrized and sampled. In this paper, we propose to remesh an arbitrary surface onto a completely regular structure we call a geometry image. It captures geometry as a simple 2D array of quantized points. Surface signals like normals and colors are stored in similar 2D arrays using the same implicit surface parametrization -texture coordinates are absent. To create a geometry image, we cut an arbitrary mesh along a network of edge paths, and parametrize the resulting single chart onto a square. Geometry images can be encoded using traditional image compression algorithms, such as wavelet-based coders.

An exciting new area in computer graphics is the synthesis of novel images with photographic effect from an initial database of reference images. This is the primary theme of imagebased rendering algorithms. This research extends the light field and lumigraph image-based rendering methods and greatly extends their utility, especially in scenes with much depth variation. First, we have added the ability to vary the apparent focus within a light field using intuitive camera-like controls such as a variable aperture and focus ring. As with lumigraphs, we allow for more general and flexible focal surfaces than a typical focal plane.However, this parameterization works independently of scene geometry; we do not need to recover actual or approximate geometry of the scene for focusing. In addition, we present a method for using multiple focal surfaces in a single image rendering process.

We present a novel approach to parameterize a mesh with disk topology to the plane in a shapeWe present also a more general "hybrid" parameterization model which provides a continuous spectrum of possibilities, controlled by a single parameter. The two cases described above lie at the two ends of the spectrum. We generalize our local/global algorithm to compute these parameterizations. The local phase may also be accelerated by parallelizing the independent computations per triangle.