A Weighted Two-Level Bregman Method with Dictionary Updating for Nonconvex MR Image Reconstruction

Figure 2

Performance of algorithms at different sampling trajectories with the same undersampling ratio. The first line ((a), (b), (c), and (d)): the variable density 2D random sampling, Cartesian approximation of multishot spiral sampling, Cartesian sampling, and pseudo radial sampling with 86% acceleration factor, respectively. The second and third lines are the reconstruction errors of DLMRI and WTBMDU-L1 with for the four sampling masks.

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)

(i)

(j)

(k)

(l)