Advances in 3D scanning technologies have enabled the practical creation of meshes with hundreds of millions of polygons. Traditional algorithms for display, simplification, and progressive transmission of meshes are impractical for data sets of this size. We describe a system for representing and progressively displaying these meshes that combines a multiresolution hierarchy based on bounding spheres with a rendering system based on points. A single data structure is used for view frustum culling, backface culling, level-of-detail selection, and rendering. The representation is compact and can be computed quickly, making it suitable for large data sets. Our implementation, written for use in a large-scale 3D digitization project, launches quickly, maintains a user-settable interactive frame rate regardless of object complexity or camera position, yields reasonable image quality during motion, and refines progressively when idle to a high final image quality. We have demonstrated the system on scanned models containing hundreds of millions of samples.

In this paper, we propose a valence-driven, single-resolution encoding technique for lossless compression of triangle mesh connectivity. Building upon a valence-based approach pioneered by Touma and Gotsman 22, we design a new valence-driven conquest for arbitrary meshes that always guarantees smaller compression rates than the original method. Furthermore, we provide a novel theoretical entropy study of our technique, hinting the optimality of the valence-driven approach. Finally, we demonstrate the practical efficiency of this approach (in agreement with the theoretical prediction) on a series of test meshes, resulting in the lowest compression ratios published so far, for both irregular and regular meshes, small or large.

We present the 3D Video Recorder, a system capable of recording, processing, and playing three–dimensional video from multiple points of view. We first record 2D video streams from several synchronized digital video cameras and store pre-processed images to disk. An off-line processing stage converts these images into a time–varying three– dimensional hierarchical point–based data structure and stores this 3D video to disk. We show how we can trade–off 3D video quality with processing performance and devise efficient compression and coding schemes for our novel 3D video representation. A typical sequence is encoded at less than 7 megabit per second at a frame rate of 8.5 frames per second. The 3D video player decodes and renders 3D videos from hard–disk in real–time, providing interaction features known from common video cassette recorders, like variable–speed forward and reverse, and slow motion. 3D video playback can be enhanced with novel 3D video effects such as freeze–and–rotate and arbitrary scaling. The player builds upon point–based rendering techniques and is thus capable of rendering high–quality images in real–time. Finally, we demonstrate the 3D Video Recorder on multiple real–life video sequences. 1

We present the 3D Video Recorder, a system capable of recording, processing, and playing three-dimensional video from multiple points of view. We first record 2D video streams from several synchronized digital video cameras and store pre-processed images to disk. An off-line processing stage converts these images into a time-varying 3D hierarchical point-based data structure and stores this 3D video to disk. We show how we can trade-off 3D video quality with processing performance and devise efficient compression and coding schemes for our novel 3D video representation. A typical sequence is encoded at less than 7 Mbps at a frame rate of 8.5 frames per second.

A height field is a set of height distance values sampled at a finite set of sample points in a two-dimensional parameter domain. A height field usually contains a lot of redundant information, much of which can be removed without a substantial degradation of its quality. A common approach to reducing the size of a height field representation is to use a piecewise polygonal surface approximation. This consists of a mesh of polygons that approximates the surfaces of the original data at a desired level of accuracy. Polygonal surface approximation of height fields has numerous applications in the fields of computer graphics and computer vision. Triangular mesh approximations are a popular means of representing three-dimensional surfaces, and multiresolution analysis (MRA) is often used to obtain compact representations of dense input data, as well as to allow surface approximations at varying spatial resolution. Multiresolution approaches, particularly those moving from coarse to fine resolutions, can often improve the computational efficiency of mesh generation as well as can provide easy control of level of details for approximations.