Qualitative Visual Interpretation of 3d Hand Gestures Using Motion Parallax

We present an efficient and geometrically intuitive algorithm to reliably interpret the image velocities of moving objects in 3D. It is well known that in a small neighbourhood the image motion of points on a plane is characterised by an affine transformation. We show that the relative image motion of a nearby non-coplanar point and its projection on the plane is equivalent to motion parallax and that it is a reliable geometric cue to 3D shape and viewer/object motion. In particular we show how to interpret the motion parallax vector of a fourth point and the curl, divergence and deformation components of the affine transformation (defined by the three points of the plane) in order to recover the projection of the axis of rotation of a moving object; the change in relative position of the object; the rotation about the ray; the tilt of the surface and a one parameter family of solutions for the slant as a function of the magnitude of the rotation of the object. The latter is a manifes...

• Type: Conference
• Year: 1992
• Where: MVA
• Authors: Roberto Cipolla, Yasukazu Okamoto, Yoshinori Kuno
• Keywords: Affine Transformation, Image Motion, Motion Parallax, MVA 1992, MVA 2007