Focal Loss with Label Smoothing

Label Smoothing applied in Focal Loss
This code is based on the below papers.

• Focal Loss for Dense Object Detection.
• When Does Label Smoothing Help?

How to use

criteria = FocalLossWithSmoothing(num_classes)

logits = model(inputs)
loss = criteria(logits, labels)

optim.zero_grad()
loss.backward()
optim.step()