i was trying to code the equation 7 of Turk,Pentland paper 'eigenfaces for recognition' The equation says for an image l ,the components in eigen space is wk=uk.T (l-Psi) where uk is a single eigenface vector and Psi is the average image

i have an ndarray L that contains data of 1 image per row. if there are M total images each of N pixels ,then L is of shape(MxN) I calculated eigenfaces(U) such that each row is an eigenface(ie,uk) U is of shape(MxN)

I saw in a posting http://groups.google.com/group/sci.image.processing/browse_thread/thread/723... that The components in 'face-space' of a face image I (Nx 1 vector) are wk = uk o (I - Psi), where Psi is the average over the M face images; o denotes scalar product, uk is eigenface k.

but here i am using each image as 1xN vector .And i want to take only m eigenfaces instead of M. how should i calculate the weight space from this ?should i do W=dot(U[:m,:],(L-Psi).transpose() ) do i have to transpose this result again?

thanks harryos