Table 1.

Experimental results of different kinds of encoders.

Network model	Mammography	Lung nodule	Endocardium	Epicardium
Encoder (A)	0.8928	0.8867	0.8901	0.9328
Encoder (B)	0.8744	0.8803	0.7696	0.8158
Encoder (C)	0.8923	0.8878	0.8811	0.9280
U-Net	0.8939	0.8842	0.8797	0.9299

The dice coefficient was used as the evaluation metric for each case. Encoder (A), (B), and (C) are all connected to general decoder. The structures of the encoder (A), (B), and (C) are shown in Figure 1.