Efficient Boundary Detection and Transfer Function Generation in Direct Volume Rendering

Abstract

In this paper we present an efficient technique for the construction of LH histograms which, in contrast to previous work, does not require an expensive tracking of intensity profiles across boundaries and therefore allows an LH classification in real time. We propose a volume exploration system for the semi-automatic generation of LH transfer functions, which does not require any user interaction within the transfer function domain. During an iterative process the user extracts features by marking them directly in the volume rendered image. The system automatically detects a marked feature’s boundary by exploiting our novel LH technique and generates a suitable component transfer function that associates user-specified optical properties with the region representing the boundary in the transfer function space. The component functions thus generated are automatically combined to produce an LH transfer function to be used for rendering.