3D Pose Tracking with Linear Depth and Brightness Constraints
M. Harville, A. Rahimi,
T. Darrell, G. Gordon, J. Woodfill Interval Research Corp., 1801C Page Mill Road, Palo Alto, CA 94304 harville,rahimi,trevor,gaile,woodfill@interval.com
This paper explores the direct motion estimation problem assuming that
video-rate depth information is available, from either stereo cameras or
other sensors. We use these depth measurements in the traditional linear
brightness constraint equations, and we introduce a new depth constraint
equation. As a result, estimation of certain types of motion, such as translation
in depth and rotations out of the image plane, becomes more robust. We
derive linear brightness and depth change constraint equations that govern
the velocity field in 3-D for both perspective and orthographic camera
projection models. These constraints are integrated jointly over image
regions according to a rigid-body motion model, yielding a single linear
system to robustly track 3D object pose. Results are shown for tracking
the pose of faces in sequences of synthetic and real images. For a color
version of this paper and for video result sequences, see http://www.interval.com/papers/1999-006.