Table 1. Image similarity.

The group mean (± group standard deviation) across the 20 HCP subjects of the mean absolute error (MAE), peak signal-to-noise ratio (PSNR) and structural similarity index measure (SSIM) of b = 0 images and the diffusion-weighted images (DWI, along the same diffusion-encoding direction as the DWI shown in Figure 3) from the raw data (a), each subset of SDnDTI input data (b–d) (a single raw b = 0 image or DWIs synthesized from the diffusion tensor fitted using three b = 0 images and six DWIs), the averaged b = 0 image or DWIs synthesized from the diffusion tensor fitted using three b = 0 images and 18 DWIs (f), the raw data denoised by supervised learning with the ground-truth images as the training target (i.e., supervised-denoising) (f), each subset of SDnDTI-denoised data (g–i), the average of all three subsets of SDnDTI-denoised data (j), and the raw data denoised by BM4D (k) and AONLM (l) compared to the ground-truth images generated from the tensor fitted using all 18 b = 0 and 90 DWIs.

		a	b	c	d	e	f	9	h	i	j	k	I
		Raw	Synth. (subset 1)	Synth. (subset 2)	Synth. (subset 3)	Synth. (18 DWIs)	Supervised	SDnDTI (subset 1)	SDnDTI (subset 2)	SDnDTI (subset 3)	SDnDTI (average)	BM4D	AONLWI
MAE	b = 0		0.017 ± 0.00097	0.015 ± 0.00098	0.015 ± 0.00088	0.011 ± 0.00087	0.0099 ± 0.00073	0.014 ± 0.00091	0.013 ± 0.00087	0.013 ± 0.00078	0.01 ± 0.00082	0.014 ± 0.00063	0.013 ± 0.0007
	DWI	0.033 ± 0.0021	0.034 ± 0.0021	0,035 ± 0.0021	0.035 ± 0.0022	0.019 ± 0.0012	0.012 ± 0.00072	0.018 ± 0.0011	0.018 ± 0.00099	0.018 ± 0.0011	0.012 ± 0.00073	0.023 ± 0.0012	0.024 ± 0.0012
PSNR (dB)	b = 0		32.19 ± 0.62	32.94 ± 0.58	33.41 ± 0.6	35.31 ± 0.75	36.54 ± 0.76	33.18 ± 0.69	34.00 ± 0.6	34.35 ± 0.63	35.85 ± 0.77	33.67 ± 0.46	34.12 ± 0.55
	DWI	27.13 ± 0.57	26.89 ± 0.61	26.34 ± 0.61	26.45 ± 0.71	31.55 ± 0.8	35.83 ± 0.54	31.87 ± 0.86	31.68 ± 0.93	31.70 ± 1.09	34.50 ± 1.32	30.23 ± 0.47	30.16 ± 0.46
SSIM	b = 0		0.96 ± 0.0042	0.97 ± 0.004	0.97 ± 0.0039	0.99 ± 0.0023	0.99 ± 0.0019	0.98 ± 0.0029	0.98 ± 0.0025	0.98 ± 0.0024	0.99 ± 0.0018	0.98 ± 0.002	0.98 ± 0.0022
	DWI	0.88 ± 0.013	0.88 ± 0.013	0.86 ± 0.013	0.87 ± 0.013	0.95 ± 0.0054	0.98 ± 0.0023	0.96 ± 0.0047	0.96 ± 0.0047	0.96 ± 0.0047	0.98 ± 0.0024	0.94 ± 0.0056	0.94 ± 0.0058