Tags

More Optical Motion Capture

In this video, we present a high speed optical motion capture
method that can measure three dimensional motion, orientation, and
incident illumination at tagged points in a scene. We use tracking
tags that work in natural lighting conditions and can be imperceptibly
embedded in attire or other objects. Our system supports an
unlimited number of tags in a scene, with each tag uniquely identified
to eliminate marker reacquisition issues. Our tags also provide
incident illumination data which can be used to match scene lighting
when inserting synthetic elements. The technique is therefore
ideal for on-set motion capture or real-time broadcasting of virtual
sets.

Unlike previous methods that employ high speed cameras or scanning
lasers, we capture the scene appearance using the simplest
possible optical devices -- a light-emitting diode (LED) with a passive
binary mask used as the transmitter and a photosensor used as
the receiver. We strategically place a set of optical transmitters to
spatio-temporally encode the volume of interest. Photosensors attached
to scene points demultiplex the coded optical signals from
multiple transmitters, allowing us to compute not only receiver location
and orientation but also their incident illumination and the
reflectance of the surfaces to which the photosensors are attached.
We use our untethered tag system, called Prakash, to demonstrate
methods of adding special effects to captured videos that cannot
be accomplished using pure vision techniques that rely on camera
images.

Category:

Howto & Style

Tags:

• MotionCapture
• Mocap
• Illumination
• Actor
• Actress
• MERL