Interactive Out-of-Core Exploration of Large Volume Datasets in VTK-Based Visualisation Systems

Abstract

The Visualisation ToolKit (VTK) has become a very popular tool for scientific data visualisation and it is used as a base in many existing visualisation systems. Scientific datasets produced nowadays by complex scientific simulations or by modern data acquisition techniques (e.g., airborne laser scanning) are often too large to be processed in one piece on commodity hardware, as simply storing it requires several giga-bytes. Although VTK provides a means for processing such datasets, their straightforward use is rarely efficient. This paper describes an efficient interactive exploration of large volume datasets under the Multimod Application Framework (MAF) [VZT*07], a VTK-based system; however, the proposed approach can be adopted for other systems with ease. It exploits various techniques such as multi-resolution layout and a volume bricking scheme to access data at an interactive rate. A user can explore the dataset by specifying a region of interest (ROI), which leads to the generation of a more accurate data representation inside the ROI. If even more precise accuracy is needed inside the ROI, nested ROIs are used. Experimental results show that the user can interactively explore large volume datasets such as the Visible Human male (1760x1024x1878, with a file size of 3.15 GB) on a commodity platform.