Sparse-Representation-Based Direct Minimum 𝐿^𝑝-Norm Algorithm for MRI Phase Unwrapping

Figure 5

A 256×256 MR head dataset, (a) its wrapped phases, and (b) its residue distribution including 1929 residues. Unwrapped phase images using the (c) SDM𝐿^𝑃, (d) conventional minimum 𝐿^𝑝-norm, (e) PUMA, and (f) PHUN methods. Discontinuities in the corresponding unwrapped phase images got by the (g) SDM𝐿^𝑃, (h) conventional minimum 𝐿^𝑝-norm, (i) PUMA, and (j) PHUN methods.

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