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

Figure 4

A 44×44 displacement encoded MR heart dataset, (a) its magnitudes, (b) its wrapped phases, and (c) its residue distribution including 210 residues. Unwrapped phase image using the (d) SDM𝐿^𝑃, (e) conventional minimum 𝐿^𝑝-norm, (f) PUMA, and (g) PHUN methods. Discontinuities in the corresponding unwrapped phase images got by the (h) SDM𝐿^𝑃, (i) conventional minimum 𝐿^𝑝-norm, (j) PUMA, and (k) PHUN methods.

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