This paper presents a practical framework for creating and visualizing interactive 3-D media using a system of uncalibrated projector-cameras. The proposed solution uses light patterns that temporally encode the projector’s coordinate system to solve the traditionally challenging multiframe correspondence problem by straightforward decoding instead of computational multiframe optimization. Two sets of coded light patterns (black/white stripes and colored 2x2 blocks, both of varying spatial resolutions) are presented and compared. The resulting correspondences are directly used as a compelling form of interactive 3-D media through described techniques including three-frame view synthesis, multiframe view synthesis using multiple three-frame groupings, and even single-camera view interpolation. It is shown that adapting the rendering order of the correspondences with respect to the projector’s coordinate system ensures the correct visibility for the synthesized views. Experimental results demonstrate that the framework works well for various real-world scenes, even including those with multiple objects and textured surfaces. The framework, along with the resulting correspondences, also has implications in many other computer vision and image processing applications, especially those that require multiframe correspondences.

This paper presents a method for capturing and computing 3D parallax. 3D parallax, as used here, refers to vertical offset from the ground plane, height. The method is based on analyzing shadows of vertical poles (e.g., a tall building’s contour) that sweep the object. Unlike existing beam-scanning approaches, such as shadow or structured light, that recover the distance of a point from the camera, our approach measures the height from the ground plane directly. Previous methods compute the distance from the camera using triangulation between rays outgoing from the light-source and the camera. Such a triangulation is difficult when the objects are far from the camera, and requires accurate knowledge of the light source position. In contrast, our approach intersects two (unknown) planes generated separately by two casting objects. This omits the need to precompute the location of the light source. Furthermore, it allows a moving light source to be used. The proposed setup is particularly useful when the camera cannot directly face the scene or when the object is far away from the camera. A good example is an urban scene captured by a single webcam. 1