Mulawa - 7 
L 
P of the line IL is perpendicular to the normals and r\ 2 of the planes. Thus, 
Note that if the two planes IP { and IP 2 do not intersect, the normals and r\ 2 will be 
L l and L 2 are all in the same plane. This occurs when the line IL is in an epipolar plane 
of the two photographs. The fixed point C can be estimated as follows. The fixed point 
C is a point contained in both planes IP l and IP 2 . Thus: 
(C-L 1 )«n,-0 
. , (17) 
(C-Lj)»H2 -0 
Using some approximate local reference origin C°, the fixed point C can be determined 
by including the equation: 
parallel and the norm || i'll x t| 2 || will equal zero. This degenerate case occurs when IL, 
(18) 
Then, combining the above equations, gives: 
’ll 1 [Li*»li 
il 2 T C= L 2 • Ifc 
p T I C° •0 
(19) 
( 20 )