Table 6.

Data augmentation method.

Category	Operation	Parameter Range	Purpose
Geometric	Horizontal flip	p = 0.5	Eliminate left–right orientation bias
	Vertical flip	p = 0.3	Adapt to varying capture angles
	Random scaling	0.5–1.2×	Expand size distribution
Photometric	HSV jitter	H ± 20%, S ± 30%, V ± 30%	Resist lighting/color temperature variations
Noise	Gaussian noise	σ = 0.1	Simulate sensor noise
Occlusion	Random rectangular	Area ≤20%, AR 0.5–2	Replicate hair and glare artifacts