VFloss pytorch

  

   

    

     

    
    

     

      # Loss functions
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      import torch
     
    
   

    

     

    
    

     

      import torch.nn as nn
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      from utils.general import bbox_iou
     
    
   

    

     

    
    

     

      from utils.torch_utils import is_parallel
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      def smooth_BCE(eps=0.1):  # https://github.com/ultralytics/yolov3/issues/238#issuecomment-598028441
     
    
   

    

     

    
    

     
 # return positive, negative label smoothing BCE targets
     
    
   

    

     

    
    

     
 return 1.0 - 0.5 * eps, 0.5 * eps
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      class BCEBlurWithLogitsLoss(nn.Module):
     
    
   

    

     

    
    

     
 # BCEwithLogitLoss() with reduced missing label effects.
     
    
   

    

     

    
    

     
 def __init__(self, alpha=0.05):
     
    
   

    

     

    
    

     

       super(BCEBlurWithLogitsLoss, self).__init__()
     
    
   

    

     

    
    

     

       self.loss_fcn = nn.BCEWithLogitsLoss(reduction='none')  # must be nn.BCEWithLogitsLoss()
     
    
   

    

     

    
    

     

       self.alpha = alpha
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
 def forward(self, pred, true):
     
    
   

    

     

    
    

     

       loss = self.loss_fcn(pred, true)
     
    
   

    

     

    
    

     

       pred = torch.sigmoid(pred)  # prob from logits
     
    
   

    

     

    
    

     

       dx = pred - true  # reduce only missing label effects
     
    
   

    

     

    
    

     
 # dx = (pred - true).abs() # reduce missing label and false 
     
    
  
 

文章来源: blog.csdn.net，作者：网奇，版权归原作者所有，如需转载，请联系作者。

原文链接：blog.csdn.net/jacke121/article/details/117637195