Animation Character Detection Algorithm Based on Clustering and Cascaded SSD

Table 4

Comparison of loss functions.

Loss function	Positive samples	Negative samples (big loss)	Negative samples (small loss)	Inhibition coefficient	Truncated gradient	mAP (%)
Cross entropy	✓	✓	✗	✗	✗	78.73
Focal loss	✓	✓	✓	✓	✗	78.8
Enhanced focal loss	✓	✓	✓	✓	✓	78.94