(0,0,0)
The projective plane
Why do we need homogeneous coordinates?
•represent
points at infinity, homographies, perspective projection,
multi-view relationships
What is the geometric intuition?
•a
point in the image is a ray in projective space
•Each point (x,y) on the plane is represented by a ray (sx,sy,s)
–all points on the ray are equivalent: (x, y, 1) @ (sx,
sy, s)
y
x
z
image plane (z = 1)
(sx,sy,s)
(x,y,1)