Real-time Volume Rendering Interaction in Virtual Reality

Abstract

Volume visualization using Direct Volume Rendering (DVR) techniques is used to view information inside 3D volumetric data. Data is classified using a transfer function to emphasize or filter some parts of volumetric information, such as that from Computed Tomography (CT) or Magnetic Resonance Imaging (MRI). In this paper, we introduced an application for real-time volume rendering interaction with 1D transfer functions using Virtual Reality (VR) technology based on the Oculus Rift headset and Oculus Touch controllers. Resulting images were visualized stereoscopically at 60 frames per second using a ray-casting shader, which works based on Graphics Processing Unit (GPU). To evaluate the system, 20 participants interacted with the application to complete three tasks, including a free viewpoint scan, clipping planes renderer, and an editable transfer function in the virtual environment. Then, a survey was carried out using a questionnaire to gather data. Findings showed that the average usability score for the application was 87.54, which suggested that it was highly usable.

Keywords

• direct volume rendering
• ray casting
• virtual environment
• virtual reality