A method includes receiving at least two sets of noisy basis material line integrals, each set corresponding to a different basis material and filtering the at least two sets of noisy basis material line integrals with an anti-correlation filter that at least includes a regularization term with balancing regularization factors, thereby producing de-noised basis material line integrals. An imaging system (100) includes a projection data processor (116) with an anti-correlation filter (118) that filters at least two sets of noisy basis material line integrals, each set corresponding to a different basis material, thereby producing de-noised basis material line integrals, wherein the anti-correlation filter includes a regularization term with regularization balancing factors.
