Lihi Zelnik-Manor
Michal Irani
Abstract
Traditional plane alignment techniques are typically performed between pairs of frames. In this paper we present a method for extending existing two-frame planar-motion estimation techniques into a simultaneous multi-frame estimation, by exploiting multi-frame subspace constraints of planar surfaces. The paper has three main contributions: (i) we show that when the camera calibration does not change, the collection of all parametric image motions of a planar surface in the scene across multiple frames is embedded in a low dimensional linear subspace; (ii) we show that the relative image motion of multiple planar surfaces across multiple frames is embedded in a yet lower dimensional linear subspace, even with varying camera calibration; and (iii) we show how these multi-frame constraints can be incorporated into simultaneous multi-frame estimation of planar motion, without explicitly recovering any 3D information, or camera calibration. The resulting multi-frame estimation process is more constrained than the individual two-frame estimations, leading to more accurate alignment, even when applied to small image regions.
Papers:
"Multi-Frame Estimation of Planar Motion" IEEE Trans. on Pattern Analysis and Machine Intelligence (PAMI), Vol. 22, No. 10, pp. 1105-1116, October 2000. ( zipped postscript, 3707K ; pdf, 1505K )
"Multi-Frame Alignment of Planes", CVPR'99, (zipped
postscript, 1225K ;
pdf, 467K ).
Example Sequences and Results:
Input sequence:
Aligning the house region:
Using 2-frame technique Our approach: using multi-frame technique
Aligning the road-sign region:
Using 2-frame technique Our approach: using multi-frame multi-plane technique
Questions and comments should be addressed to:
lihi@wisdom.weizmann.ac.il