title: NPU-based image compositing in a distributed visualization system.
abstract: This paper describes the first use of a Network Processing Unit (NPU) to perform hardware-based image composition in a distributed rendering system. The image composition step is a notorious bottleneck in a clustered rendering system. Furthermore, image compositing algorithms do not necessarily scale as data size and number of nodes increase. Previous researchers have addressed the composition problem via software and/or custom-built hardware. We used the heterogeneous multicore computation architecture of the Intel IXP28XX NPU, a fully programmable commercial off-the-shelf (COTS) technology, to perform the image composition step. With this design, we have attained a nearly four-times performance increase over traditional software-based compositing methods, achieving sustained compositing rates of 22-28 fps on a 1,024 x 1,024 image. This system is fully scalable with a negligible penalty in frame rate, is entirely COTS, and is flexible with regard to operating system, rendering software, graphics cards, and node architecture. The NPU-based compositor has the additional advantage of being a modular compositing component that is eminently suitable for integration into existing distributed software visualization packages.
authors.affiliation: Los Alamos National Laboratory, Los Alamos, NM 87545, USA. pugmire@lanl.gov
authors.forename: David
authors.initials: D
authors.lastname: Pugmire
authors.forename: Laura
authors.initials: L
authors.lastname: Monroe
authors.forename: Carolyn
authors.initials: C
authors.lastname: Connor Davenport
authors.forename: Andrew
authors.initials: A
authors.lastname: DuBois
authors.forename: David
authors.initials: D
authors.lastname: DuBois
authors.forename: Stephen
authors.initials: S
authors.lastname: Poole
mesh_terms: D000465:Algorithms; D003195:Computer Communication Networks / Q000295:instrumentation*; D003196:Computer Graphics; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007089:Image Enhancement / Q000295:instrumentation* / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000295:instrumentation* / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000295:instrumentation* / Q000379:methods; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*