Table 1.

Statistics of contrast enhancement

	SNR	Resolution (μm)
Low resolution (n = 15)
Original absorption	3.44 ± 0.24	1.63 ± 0.14
Denoise absorption	8.78 ± 1.34	1.86 ± 0.11
Phase retrieved	13.15 ± 1.52	2.25 ± 0.15
High resolution (n = 5)
Original absorption	1.39 ± 0.10	0.93 ± 0.17
Denoise absorption	4.27 ± 0.58	1.03 ± 0.18
Phase retrieved	18.04 ± 1.39	1.62 ± 0.12

A projection data set collected at low or high resolution was treated by three different methods before the CT reconstruction, and the three corresponding CT slices were analyzed. The SNR value was calculated as an average ± 95% CI from indicated numbers of comparisons between background and compound areas of 10 pixels × 10 pixels each for the low-resolution images and of 16 pixels × 16 pixels each for the high-resolution images, according to the definition described in “Methods” section. The resolution value was calculated as an average ± 95% CI from indicated numbers of line profiles of 25 μm for the low-resolution images and of 10–15 μm for the high-resolution images, according to the procedure described in “Methods” section