Hardware-accelerated autostereogram rendering for interactive 3D visualization

Single Image Random Dot Stereograms (SIRDS) are an attractive way of depicting three-dimensional objects using conventional display technology. Once trained in decoupling the eyes' convergence and focusing, autostereograms of this kind are able to convey the three-dimensional impression of a scene. We present in this work an algorithm that generates SIRDS at interactive frame rates on a conventional PC. The presented system allows rotating a 3D geometry model and observing the object from arbitrary positions in real-time. Subjective tests show that the perception of a moving or rotating 3D scene presents no problem: The gaze remains focused onto the object. In contrast to conventional SIRDS algorithms, we render multiple pixels in a single step using a texture-based approach, exploiting the parallel-processing architecture of modern graphics hardware. A vertex program determines the parallax for each vertex of the geometry model, and the graphics hardware's texture unit is used to render the dot pattern. No data has to be transferred between main memory and the graphics card for generating the autostereograms, leaving CPU capacity available for other tasks. Frame rates of 25 fps are attained at a resolution of 1024x512 pixels on a standard PC using a consumer-grade nVidia GeForce4 graphics card, demonstrating the real-time capability of the system.