Table 4. Impact of the structural similarity lower limit ζ.

Model info	Training costs		Visual quality			Attack performance
	TruePert	Epoch	SSIM	PSNR	MSE	ASR1	ASR2	FSS&FTS
ɛ = 4 w.o. ζ w.o. η	4.00	990	94.32	33.32	27.55	71.23	40.63	47.39&51.09
ɛ = 4ζ = 0.93 w.o. η	3.82	990	95.46	33.70	25.20	68.38	43.32	50.70&49.78
ɛ = 4ζ = 0.97 w.o. η	3.49	990	96.33	34.65	21.13	64.12	42.15	53.86&47.57
ɛ = 5 w.o. ζ w.o. η	5.01	990	91.73	31.32	43.30	79.22	30.38	38.73&56.09
ɛ = 5ζ = 0.92 w.o. η	4.50	990	94.50	32.38	34.92	75.48	39.33	45.57&53.09
ɛ = 5ζ = 0.95 w.o. η	3.97	990	95.62	33.52	27.80	69.53	38.30	48.41&50.23
ɛ = 5w.o.ζ η = 0.15	4.95	990	92.72	31.46	42.16	75.48	42.25	47.82&53.36
ɛ = 5ζ = 0.92η = 0.15	4.41	990	94.62	32.57	33.72	70.57	43.92	51.76&50.96
ɛ = 5ζ = 0.95η = 0.15	4.31	2490	95.13	32.70	32.50	73.57	48.03	52.35&52.23