Fig. 1. Schematic drawing of the imaging system with sub-detector sampling

Fig. 2. FORBILD phanthom with high-contrast ear section，the digital phantoms are sampled on a 512×512 grid

Fig. 3. Reconstructed images from data generated with a discrete FORBILD head phantom. All images are displayed using the same displaying window of [0.207, 0.215](cm^-1)

Fig. 4. The curves of cPD (dn), DTV(dn), Dd(dn) and Dh(dn) with the number of iterations

Fig. 5. Reconstructed images from poisson noisy data. All images are displayed using the same displaying window of [0.207, 0.215](cm^-1)

Fig. 6. Profile plots across the lines in Fig. 2 from reconstructed noisy images