Research Article

Efficient CT Metal Artifact Reduction Based on Fractional-Order Curvature Diffusion

Figure 2

Masks of the four directions: (a) 𝐷 𝛼 𝑥 + , (b) 𝐷 𝛼 𝑥 , (c) 𝐷 𝛼 𝑦 + , and (d) 𝐷 𝛼 𝑦 .
173748.fig.002a
(a)
173748.fig.002b
(b)
173748.fig.002c
(c)
173748.fig.002d
(d)