File size: 4,940 Bytes
cc0c59d
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
from typing import *
import copy
import torch
import torch.nn.functional as F
from torch.utils.data import DataLoader
from easydict import EasyDict as edict

from ..basic import BasicTrainer


class SparseStructureVaeTrainer(BasicTrainer):
    """
    Trainer for Sparse Structure VAE.
    
    Args:
        models (dict[str, nn.Module]): Models to train.
        dataset (torch.utils.data.Dataset): Dataset.
        output_dir (str): Output directory.
        load_dir (str): Load directory.
        step (int): Step to load.
        batch_size (int): Batch size.
        batch_size_per_gpu (int): Batch size per GPU. If specified, batch_size will be ignored.
        batch_split (int): Split batch with gradient accumulation.
        max_steps (int): Max steps.
        optimizer (dict): Optimizer config.
        lr_scheduler (dict): Learning rate scheduler config.
        elastic (dict): Elastic memory management config.
        grad_clip (float or dict): Gradient clip config.
        ema_rate (float or list): Exponential moving average rates.
        fp16_mode (str): FP16 mode.
            - None: No FP16.
            - 'inflat_all': Hold a inflated fp32 master param for all params.
            - 'amp': Automatic mixed precision.
        fp16_scale_growth (float): Scale growth for FP16 gradient backpropagation.
        finetune_ckpt (dict): Finetune checkpoint.
        log_param_stats (bool): Log parameter stats.
        i_print (int): Print interval.
        i_log (int): Log interval.
        i_sample (int): Sample interval.
        i_save (int): Save interval.
        i_ddpcheck (int): DDP check interval.
        
        loss_type (str): Loss type. 'bce' for binary cross entropy, 'l1' for L1 loss, 'dice' for Dice loss.
        lambda_kl (float): KL divergence loss weight.
    """
    
    def __init__(
        self,
        *args,
        loss_type='bce',
        lambda_kl=1e-6,
        **kwargs
    ):
        super().__init__(*args, **kwargs)
        self.loss_type = loss_type
        self.lambda_kl = lambda_kl
    
    def training_losses(
        self,
        ss: torch.Tensor,
        **kwargs
    ) -> Tuple[Dict, Dict]:
        """
        Compute training losses.

        Args:
            ss: The [N x 1 x H x W x D] tensor of binary sparse structure.

        Returns:
            a dict with the key "loss" containing a scalar tensor.
            may also contain other keys for different terms.
        """
        z, mean, logvar = self.training_models['encoder'](ss.float(), sample_posterior=True, return_raw=True)
        logits = self.training_models['decoder'](z)

        terms = edict(loss = 0.0)
        if self.loss_type == 'bce':
            terms["bce"] = F.binary_cross_entropy_with_logits(logits, ss.float(), reduction='mean')
            terms["loss"] = terms["loss"] + terms["bce"]
        elif self.loss_type == 'l1':
            terms["l1"] = F.l1_loss(F.sigmoid(logits), ss.float(), reduction='mean')
            terms["loss"] = terms["loss"] + terms["l1"]
        elif self.loss_type == 'dice':
            logits = F.sigmoid(logits)
            terms["dice"] = 1 - (2 * (logits * ss.float()).sum() + 1) / (logits.sum() + ss.float().sum() + 1)
            terms["loss"] = terms["loss"] + terms["dice"]
        else:
            raise ValueError(f'Invalid loss type {self.loss_type}')
        terms["kl"] = 0.5 * torch.mean(mean.pow(2) + logvar.exp() - logvar - 1)
        terms["loss"] = terms["loss"] + self.lambda_kl * terms["kl"]
            
        return terms, {}
    
    @torch.no_grad()
    def snapshot(self, suffix=None, num_samples=64, batch_size=1, verbose=False):
        super().snapshot(suffix=suffix, num_samples=num_samples, batch_size=batch_size, verbose=verbose)
    
    @torch.no_grad()
    def run_snapshot(
        self,
        num_samples: int,
        batch_size: int,
        verbose: bool = False,
    ) -> Dict:
        dataloader = DataLoader(
            copy.deepcopy(self.dataset),
            batch_size=batch_size,
            shuffle=True,
            num_workers=0,
            collate_fn=self.dataset.collate_fn if hasattr(self.dataset, 'collate_fn') else None,
        )

        # inference
        gts = []
        recons = []
        for i in range(0, num_samples, batch_size):
            batch = min(batch_size, num_samples - i)
            data = next(iter(dataloader))
            args = {k: v[:batch].cuda() if isinstance(v, torch.Tensor) else v[:batch] for k, v in data.items()}
            z = self.models['encoder'](args['ss'].float(), sample_posterior=False)
            logits = self.models['decoder'](z)
            recon = (logits > 0).long()
            gts.append(args['ss'])
            recons.append(recon)

        sample_dict = {
            'gt': {'value': torch.cat(gts, dim=0), 'type': 'sample'},
            'recon': {'value': torch.cat(recons, dim=0), 'type': 'sample'},
        }
        return sample_dict