James Davis, Hector Gonzales-Banos
Computer vision researchers have long sought video rate sensors which return a channel of depth, in addition to color. One promising technology to make this possible is based on a projector-camera pair that generate shuttered pulses of light. Commercial implementations of the hardware technology are available today. Unfortunately, the software models that allow recovery of depth measurements suffer from relatively high noise and bias. This paper describes a mathematical recovery model for this class of shuttered sensors. The model is useful for understanding the behavior of these sensors, and is validated against empirical data. Based on our model, we introduce two specific methods for improving the quality of recovered depth. Multi-intensity estimation makes use of several observations with varying lamp intensities, and double shuttering suggests that improved performance can be obtained using two shutters instead of one.
IEEE International Workshop on Projector-Camera Systems 2003 [PDF]