495 / 1228
1. I need to be efficient
Our oversimplified example on a plane (one array
of voxels or one image):
scerma does not vary with θ within ΔΩ
less
fitting for B
θ
, b
θ
BUT
•
I still need to evaluate D
i->j
for all points j at
different radial distance
OR
•
I could evaluate D
i->j
only for j at exactly θ
0
, φ
0
Hence each
cone
defined by ΔΩ is
collapsed
to
its main axis and
scerma from each point is
t
t d l
li
d fi d b th
ranspor e a ong nes e ne y e
directions from volume discretization in ΔΩ
(order of evaluations required~MN
4
)