Focal loss

• focal loss with multi-label implemented in keras.
• reference to paper : Focal Loss for Dense Object Detection
• add LSR (label smoothing regularization)

Usage

• firstly, you should get a list which contains each class number, like classes_nu=[1,2,3] means index_0 class have 1 pic, index_1 class have 1 pics, index_2 class have 3 pics.
• then, use the focal loss function like below:

model.compile(optimizer=SGD(lr=learning_rate, momentum=0.9), loss=[focal_loss(classes_num)], metrics=['accuracy'])

blog of focal loss

• focal loss论文笔记(附基于keras的多类别focal loss代码)