VIZARD II: A Reconfigurable Interactive Volume Rendering System

Abstract

This paper presents a reconfigurable, hardware accelerated, volume rendering system for high quality perspective ray casting. The volume rendering accelerator performs ray casting by calculating the path of the ray through the volume using a programmable Xilinx Virtex FPGA which provides fast design changes and low cost development. Volume datasets are stored on the card in low profile DIMMs with standard connectors allowing both, large datasets up to 1 GByte with 32 bit per voxel, and easy upgrades to larger memory capacities. Per-sample Phong shading and post-classification is performed in hardware, giving immediate feedback to changes in the visualization of a dataset. Adding new features, such as pre-integrated classification, can be accomplished using the existing card without expensive and time consuming redesigns. The card can also be used for medical image reconstruction by reconfiguring the FPGA broadening its usefulness for end users. For the first time, users are able to generate high quality perspective images as required for applications such as virtual endoscopy and colonoscopy, and stereoscopic image generation.