No Invariants, so Capture Variation
•Each image = a pt. in a high-dimensional space.
–Image: Each pixel a dimension.
–Point set: Each coordinate of each pt. A dimension.
•Simplest rep. of variation is linear.
–Basis (eigen) images: x1…xk
–Each image, x = a1x1 + … + akxk
•Useful if k << n.