Table 3.

The performance of models was evaluated by DB metrics FID scores and KID scores, alongside the subjective MOS rating. The results are referred to categories with reference (’W Ref’), without reference (’W/O Ref’), and total (‘Total’) image sets. For each column, the best result is colored in red and the second best is colored in blue

Model	W Ref				W/O Ref				Total
	FID768↓	FID2048↓	KID↓	MOS↑	FID768↓	FID2048↓	KID↓	MOS↑	FID768↓	FID2048↓	KID↓	MOS↑
UNSB	1.659	313.189	0.597	29.300	1.611	301.666	0.655	25.360	1.622	304.325	0.641	26.269
2D CycleGAN	1.547	225.302	0.300	36.667	1.420	231.048	0.326	41.630	1.449	229.722	0.320	40.485
3D CycleGAN-GL	1.281	202.795	0.267	50.400	1.170	169.556	0.215	49.550	1.195	177.227	0.227	49.746
3D CycleGAN–2	0.852	149.486	0.144	53.967	0.890	166.473	0.160	52.860	0.881	162.553	0.156	53.115
3D CycleGAN–3	0.766	154.756	0.153	56.867	0.780	155.188	0.156	56.350	0.777	155.089	0.155	56.469

Note: FID768 and FID2048 refer to the Fréchet Inception Distance computed with 768 and 2048 features, respectively. KID refers to the Kernel Inception Distance. Both FID and KID indicate better performance with lower scores. Mean Opinion Score (MOS) rates the subjective quality of images with higher scores reflecting better quality.