A virtual protractor is used to measure angles between objects perceived in
stereo image pairs using virtual reality technology. Each image is generated
from a scanning electron microscope, and stereo pairs are obtained by either
manipulating the specimen or the electron beam. Images from slightly
different viewpoints are combined using stereoscopic rendering to create
the illusion of a 3D scene. Virtual reality user interface technology is
used to manipulate a virtual measuring device with the goal of accurately
measuring spatial characteristics of 3D objects perceived while viewing
the stereo image pairs. This approach relies on the human observers'
ability to successfully fuse stereo geometry and image-based data. A
paper was presented at IEEE Vis99 that describes our work.