The 3D tagging system and the authoring procedure. (a) The tagging system consists of an IR projector with a co-located color camera and an IR camera. An image from the color camera is used to select scene points for tagging. The IR camera has a different viewpoint from the projector and is used to estimate the 3D positions of the tags. (b) An image used to select scene points (white dots) for tagging. (c) The corresponding tag locations in the projector image.
(d) One image (contrast enhanced for illustration) from the sequence captured by the IR camera, in which the tags are clearly visible. (e) The computed 3D coordinates of the tags.