Entry Date:
December 26, 2006

Role of Learning in 3D Form Perception

Principal Investigator Pawan Sinha

One of the most enduring questions about human vision is how we are able to perceive three-dimensionality in two-dimensional images, even in the absence of motion, stereo, shading and texture cues. Traditionally, researchers have posited the use of innately specified brain mechanisms, such as a preference for simplicity. To test these ideas, we have developed a computational system for recovering 3D structures from single 2D line-drawings, using a fixed set of constraints that partly capture the notion of perceptual simplicity. While the system is able to mimic human performance for a small set of inputs, it exhibits significant limitations when analyzing natural imagery. To account for these shortcomings, we have proposed a learning-based theory, and have gathered experimental data that provide strong evidence for a role of object-specific learning in the perception of 3D structure. Together, the computational and experimental studies provide a good foundation for building a more comprehensive account of 3D shape perception in single 2D images.