Figure 2.

U-Net network architecture for this study. The U-Net network architecture is composed of a contracting path, an expansive path, and a final layer. The contracting path is made up of repetitive applications of two 3 × 3 convolutions and a 2 × 2 max pooling operation with stride 2 for down-sampling. The expansive path exists of two 3 × 3 convolutions and a 2 × 2 convolution for up-sampling. The final layer employs a 1 × 1 convolution for mapping each 16-component feature vector for the required number of classes.