File size: 1,036 Bytes
72c1765
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
import torch
import torch.nn as nn
import torch.nn.functional as F

try:
    from LovaszSoftmax.pytorch.lovasz_losses import lovasz_hinge
except ImportError:
    pass

__all__ = ['BCEDiceLoss', 'LovaszHingeLoss']


class BCEDiceLoss(nn.Module):
    def __init__(self):
        super().__init__()

    def forward(self, input, target):
        bce = F.binary_cross_entropy_with_logits(input, target)
        smooth = 1e-5
        input = torch.sigmoid(input)
        num = target.size(0)
        input = input.view(num, -1)
        target = target.view(num, -1)
        intersection = (input * target)
        dice = (2. * intersection.sum(1) + smooth) / (input.sum(1) + target.sum(1) + smooth)
        dice = 1 - dice.sum() / num
        return 0.5 * bce + dice


class LovaszHingeLoss(nn.Module):
    def __init__(self):
        super().__init__()

    def forward(self, input, target):
        input = input.squeeze(1)
        target = target.squeeze(1)
        loss = lovasz_hinge(input, target, per_image=True)

        return loss