Fig. 11.

Reconstruction results of sinograms of circular phantom using different methods under different projections. (a)-(c) Original sinograms (raw data) under 128, 64, and 32 projections, respectively. (d)-(f) Reconstructed sinograms using the Cycle-GAN method. (g)-(i) Reconstructed sinograms using the Attention-based U-Net method. (j)-(l) Reconstructed sinograms using the diffusion model method. (m)-(o) Reconstructed sinograms using the U-Net method. (p)-(r) Reconstructed sinograms using the proposed method. (s) Ground truth sinogram for reference. Yellow numbers at the bottom of each figure are the SSIM values. (t) and (u) The close-up images indicated by the green boxes 1 and 2 in (s), respectively. Yellow arrows highlight differences in reconstructed details between methods. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)