File size: 5,072 Bytes
a3b520a
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
"""Training script for the kick drum VAE."""

import sys
from pathlib import Path

import torch
from torch.utils.data import DataLoader, Dataset, random_split
from torch.utils.tensorboard import SummaryWriter
from tqdm import tqdm

# Add project root to path
sys.path.insert(0, str(Path(__file__).parent.parent))

from models.autoencoder import KickVAE
from training.config import AutoencoderConfig
from training.losses import vae_loss


class MelDataset(Dataset):
    """Dataset of preprocessed mel spectrogram tensors."""

    def __init__(self, data_dir: Path) -> None:
        self.files = sorted(
            f for f in data_dir.glob("*.pt") if not f.name.startswith("._")
        )
        if not self.files:
            raise FileNotFoundError(
                f"No .pt files found in {data_dir}"
            )

    def __len__(self) -> int:
        return len(self.files)

    def __getitem__(self, idx: int) -> torch.Tensor:
        return torch.load(self.files[idx], weights_only=False)


def train(cfg: AutoencoderConfig | None = None) -> None:
    """Run VAE training."""
    if cfg is None:
        cfg = AutoencoderConfig()

    device = torch.device(
        "cuda" if torch.cuda.is_available()
        else "mps" if torch.backends.mps.is_available()
        else "cpu"
    )
    print(f"Using device: {device}")

    # Data
    dataset = MelDataset(cfg.data_dir)
    val_size = int(len(dataset) * cfg.val_split)
    train_size = len(dataset) - val_size
    train_set, val_set = random_split(
        dataset, [train_size, val_size],
        generator=torch.Generator().manual_seed(42),
    )

    train_loader = DataLoader(
        train_set,
        batch_size=cfg.batch_size,
        shuffle=True,
        num_workers=cfg.num_workers,
        pin_memory=True,
    )
    val_loader = DataLoader(
        val_set,
        batch_size=cfg.batch_size,
        shuffle=False,
        num_workers=cfg.num_workers,
        pin_memory=True,
    )

    print(f"Train: {train_size}, Val: {val_size}")

    # Model
    model = KickVAE(latent_dim=cfg.latent_dim).to(device)
    optimizer = torch.optim.AdamW(model.parameters(), lr=cfg.learning_rate)
    scaler = torch.amp.GradScaler(enabled=cfg.use_amp and device.type == "cuda")

    # Logging
    cfg.log_dir.mkdir(parents=True, exist_ok=True)
    cfg.checkpoint_dir.mkdir(parents=True, exist_ok=True)
    writer = SummaryWriter(cfg.log_dir)

    global_step = 0

    for epoch in range(cfg.epochs):
        model.train()
        kl_weight = cfg.kl_weight_at_epoch(epoch)

        epoch_metrics: dict[str, float] = {}
        epoch_count = 0

        pbar = tqdm(train_loader, desc=f"Epoch {epoch+1}/{cfg.epochs}")
        for batch in pbar:
            batch = batch.to(device)

            with torch.amp.autocast(
                device_type=device.type,
                enabled=cfg.use_amp and device.type == "cuda",
            ):
                recon, mu, logvar = model(batch)
                loss, metrics = vae_loss(
                    recon, batch, mu, logvar, kl_weight
                )

            optimizer.zero_grad()
            scaler.scale(loss).backward()
            scaler.step(optimizer)
            scaler.update()

            # Accumulate metrics
            for k, v in metrics.items():
                epoch_metrics[k] = epoch_metrics.get(k, 0.0) + v
            epoch_count += 1
            global_step += 1

            pbar.set_postfix(loss=f"{metrics['total']:.4f}")

        # Log epoch averages
        for k, v in epoch_metrics.items():
            writer.add_scalar(f"train/{k}", v / epoch_count, epoch)
        writer.add_scalar("train/kl_weight", kl_weight, epoch)

        # Validation
        model.eval()
        val_metrics: dict[str, float] = {}
        val_count = 0

        with torch.no_grad():
            for batch in val_loader:
                batch = batch.to(device)
                recon, mu, logvar = model(batch)
                _, metrics = vae_loss(
                    recon, batch, mu, logvar, kl_weight
                )
                for k, v in metrics.items():
                    val_metrics[k] = val_metrics.get(k, 0.0) + v
                val_count += 1

        avg_val_loss = val_metrics.get("total", 0.0) / max(val_count, 1)
        for k, v in val_metrics.items():
            writer.add_scalar(f"val/{k}", v / val_count, epoch)

        print(
            f"Epoch {epoch+1}: "
            f"train={epoch_metrics['total']/epoch_count:.4f} "
            f"val={avg_val_loss:.4f} "
            f"kl_w={kl_weight:.6f}"
        )

        # Checkpoint
        if (epoch + 1) % cfg.checkpoint_every == 0:
            path = cfg.checkpoint_dir / f"vae_epoch_{epoch+1}.pt"
            torch.save({
                "epoch": epoch + 1,
                "model_state_dict": model.state_dict(),
                "optimizer_state_dict": optimizer.state_dict(),
                "config": cfg,
            }, path)
            print(f"Saved checkpoint: {path}")

    writer.close()
    print("Training complete.")


if __name__ == "__main__":
    train()