  An algorithm to efficiently compute the moments of volumetric images is
disclosed. The approach demonstrates a reduction in processing time by reducing
the computational complexity significantly. Specifically, the algorithm reduces
multiplicative complexity from O(n^3) to O(n). Several 2D projection images of
the 3D volume are generated. The algorithm computes a set of 2D moments from
those 2D images. Those 2D moments are then used to derive the 3D volumetric
moments. Examples of use in MRI or CT and related analysis demonstrates the
benefit of the Discrete Projection Moment Algorithm. The approach is also
useful in computing the moments of a 3D object using a small set of 2D
tomographic images of that object.
