f15e02b0b8
- Always sample dataset[0] with fixed noise seed so checkpoints are directly comparable (hear the model improve step by step) - Save to output_dir/samples/step_XXXXX.wav instead of alongside checkpoints Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
735 lines
32 KiB
Python
735 lines
32 KiB
Python
import copy
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import json
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import random
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import traceback
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from pathlib import Path
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import numpy as np
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import torch
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import torch.nn.functional as F
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import torchaudio
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from PIL import Image, ImageDraw
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import comfy.utils
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import folder_paths
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from .utils import SELVA_CATEGORY, get_device, soft_empty_cache
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from selva_core.model.utils.features_utils import FeaturesUtils
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from selva_core.model.flow_matching import FlowMatching
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from selva_core.model.lora import apply_lora, get_lora_state_dict, load_lora
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_AUDIO_EXTS = {".wav", ".flac", ".mp3", ".ogg", ".aiff", ".aif"}
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_SELVA_DIR = Path(folder_paths.models_dir) / "selva"
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# ---------------------------------------------------------------------------
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# Data helpers (mirror train_lora.py)
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# ---------------------------------------------------------------------------
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def _load_prompts(data_dir: Path) -> dict:
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p = data_dir / "prompts.txt"
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if not p.exists():
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return {}
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mapping = {}
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for line in p.read_text(encoding="utf-8").splitlines():
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line = line.strip()
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if not line or line.startswith("#"):
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continue
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if ":" in line:
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fname, prompt = line.split(":", 1)
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mapping[fname.strip()] = prompt.strip()
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return mapping
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def _find_audio(npz_path: Path) -> Path | None:
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for ext in _AUDIO_EXTS:
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c = npz_path.with_suffix(ext)
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if c.exists():
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return c
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return None
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def _load_audio(path: Path, target_sr: int, duration: float) -> torch.Tensor:
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try:
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waveform, sr = torchaudio.load(str(path))
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except RuntimeError as e:
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if "torchcodec" not in str(e).lower() and "libtorchcodec" not in str(e).lower():
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raise
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# torchcodec unavailable (FFmpeg shared libs missing) — fall back to soundfile
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import soundfile as sf
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data, sr = sf.read(str(path), always_2d=True) # [frames, channels]
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waveform = torch.from_numpy(data.T).float() # [channels, frames]
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if waveform.shape[0] > 1:
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waveform = waveform.mean(0, keepdim=True)
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waveform = waveform.squeeze(0).float()
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if sr != target_sr:
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waveform = torchaudio.functional.resample(
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waveform.unsqueeze(0), sr, target_sr).squeeze(0)
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target_len = int(duration * target_sr)
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if waveform.shape[0] >= target_len:
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return waveform[:target_len]
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return F.pad(waveform, (0, target_len - waveform.shape[0]))
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def _load_npz(path: Path) -> dict:
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data = np.load(str(path), allow_pickle=False)
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bundle = {
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"clip_features": torch.from_numpy(data["clip_features"]),
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"sync_features": torch.from_numpy(data["sync_features"]),
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}
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if "prompt" in data:
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bundle["prompt"] = str(data["prompt"])
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return bundle
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# ---------------------------------------------------------------------------
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# Eval sample
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# ---------------------------------------------------------------------------
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def _eval_sample(generator, feature_utils_orig, dataset, seq_cfg, device, dtype,
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num_steps: int = 8, seed: int = 0):
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"""Run a quick no-CFG inference pass on a fixed training clip.
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Always uses dataset[0] and a fixed noise seed so samples across checkpoints
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are directly comparable — you can hear the model improve step by step.
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Returns (waveform [1, L] float32 cpu, sample_rate) or (None, None) on failure.
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Uses fewer ODE steps than inference (8 vs 25) for speed.
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"""
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generator.eval()
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try:
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_, clip_f_cpu, sync_f_cpu, text_clip_cpu = dataset[0]
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clip_f = clip_f_cpu.to(device, dtype)
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sync_f = sync_f_cpu.to(device, dtype)
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text_clip = text_clip_cpu.to(device, dtype)
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rng = torch.Generator(device=device).manual_seed(seed)
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x0 = torch.randn(1, seq_cfg.latent_seq_len, generator.latent_dim,
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device=device, dtype=dtype, generator=rng)
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eval_fm = FlowMatching(min_sigma=0, inference_mode="euler", num_steps=num_steps)
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def velocity_fn(t, x):
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return generator.forward(x, clip_f, sync_f, text_clip,
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t.reshape(1).to(device, dtype))
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with torch.no_grad():
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x1_pred = eval_fm.to_data(velocity_fn, x0)
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x1_unnorm = generator.unnormalize(x1_pred)
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# feature_utils_orig may be on CPU (offload strategy) — move temporarily
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orig_device = next(feature_utils_orig.parameters()).device
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if orig_device != device:
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feature_utils_orig.to(device)
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try:
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spec = feature_utils_orig.decode(x1_unnorm)
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audio = feature_utils_orig.vocode(spec)
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finally:
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if orig_device != device:
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feature_utils_orig.to(orig_device)
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audio = audio.float().cpu()
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if audio.dim() == 2:
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audio = audio.unsqueeze(1)
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elif audio.dim() == 3 and audio.shape[1] != 1:
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audio = audio.mean(dim=1, keepdim=True)
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peak = audio.abs().max().clamp(min=1e-8)
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audio = (audio / peak).clamp(-1, 1)
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return audio.squeeze(0), seq_cfg.sampling_rate # [1, L]
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except Exception as e:
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print(f"[LoRA Trainer] Eval sample failed: {e}", flush=True)
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return None, None
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finally:
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generator.train()
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# ---------------------------------------------------------------------------
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# Loss curve rendering
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# ---------------------------------------------------------------------------
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def _smooth_losses(losses: list[float], beta: float = 0.9) -> list[float]:
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"""Exponential moving average smoothing."""
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smoothed, ema = [], None
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for v in losses:
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ema = v if ema is None else beta * ema + (1 - beta) * v
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smoothed.append(ema)
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return smoothed
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def _draw_loss_curve(losses: list[float], log_interval: int,
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start_step: int = 0, smoothed: list[float] | None = None) -> Image.Image:
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"""Render a loss curve as a PIL Image."""
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W, H = 800, 380
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pl, pr, pt, pb = 70, 20, 25, 45
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img = Image.new("RGB", (W, H), (255, 255, 255))
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draw = ImageDraw.Draw(img)
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pw = W - pl - pr
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ph = H - pt - pb
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if len(losses) >= 2:
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lo, hi = min(losses), max(losses)
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if hi == lo:
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hi = lo + 1e-6
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rng = hi - lo
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# Horizontal grid + y-axis labels
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for i in range(5):
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y = pt + int(i * ph / 4)
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val = hi - i * rng / 4
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draw.line([(pl, y), (W - pr, y)], fill=(220, 220, 220), width=1)
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draw.text((2, y - 7), f"{val:.4f}", fill=(120, 120, 120))
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# Raw loss line
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n = len(losses)
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pts = []
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for i, v in enumerate(losses):
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x = pl + int(i * pw / max(n - 1, 1))
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y = pt + int((1.0 - (v - lo) / rng) * ph)
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pts.append((x, y))
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draw.line(pts, fill=(200, 220, 255), width=1)
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# Smoothed overlay
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if smoothed is not None and len(smoothed) >= 2:
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spts = []
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for i, v in enumerate(smoothed):
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x = pl + int(i * pw / max(n - 1, 1))
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y = pt + int((1.0 - (v - lo) / rng) * ph)
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spts.append((x, y))
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draw.line(spts, fill=(66, 133, 244), width=2)
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# x-axis step labels — account for start_step so resumed runs are correct
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first_step = start_step + log_interval
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last_step = start_step + n * log_interval
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for i in range(5):
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x = pl + int(i * pw / 4)
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step = int(first_step + i * (last_step - first_step) / 4)
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draw.text((x - 12, H - pb + 5), str(step), fill=(120, 120, 120))
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# Axes
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draw.line([(pl, pt), (pl, H - pb)], fill=(40, 40, 40), width=1)
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draw.line([(pl, H - pb), (W - pr, H - pb)], fill=(40, 40, 40), width=1)
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draw.text((pl + 4, 5), "Training Loss", fill=(40, 40, 40))
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return img
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def _pil_to_tensor(img: Image.Image) -> torch.Tensor:
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"""Convert a PIL Image to a [1, H, W, 3] float32 IMAGE tensor for ComfyUI."""
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arr = np.array(img).astype(np.float32) / 255.0
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return torch.from_numpy(arr).unsqueeze(0)
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def _prepare_dataset(model: dict, data_dir: Path, device) -> list:
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"""Load VAE, encode audio clips, load .npz features.
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Returns a list of (latents, clip_features, sync_features, text_clip) CPU tensors.
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The VAE is freed after encoding. Call this once and reuse the dataset across
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multiple training jobs (e.g. in the scheduler).
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"""
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mode = model["mode"]
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seq_cfg = model["seq_cfg"]
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feature_utils_orig = model["feature_utils"]
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vae_name = "v1-16.pth" if mode == "16k" else "v1-44.pth"
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vae_path = _SELVA_DIR / "ext" / vae_name
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if not vae_path.exists():
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raise FileNotFoundError(
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f"[LoRA Trainer] VAE weight not found: {vae_path}. "
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"Run SelVA Model Loader first to auto-download weights."
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)
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print("[LoRA Trainer] Loading VAE encoder...", flush=True)
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# Keep VAE in float32: mel_converter uses torch.stft which requires float32 input.
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vae_utils = FeaturesUtils(
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tod_vae_ckpt=str(vae_path),
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enable_conditions=False,
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mode=mode,
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need_vae_encoder=True,
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).to(device).eval()
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npz_files = sorted(data_dir.glob("*.npz"))
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if not npz_files:
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raise ValueError(f"[LoRA Trainer] No .npz files found in {data_dir}")
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prompt_map = _load_prompts(data_dir)
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default_prompt = data_dir.name
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print(f"[LoRA Trainer] Pre-loading {len(npz_files)} clip(s)...", flush=True)
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pbar_load = comfy.utils.ProgressBar(len(npz_files))
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dataset = []
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for npz_path in npz_files:
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audio_path = _find_audio(npz_path)
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if audio_path is None:
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print(f" [LoRA Trainer] Warning: no audio for {npz_path.name} — skipping", flush=True)
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pbar_load.update(1)
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continue
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bundle = _load_npz(npz_path)
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prompt = prompt_map.get(npz_path.name, bundle.get("prompt", default_prompt))
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print(f" {npz_path.name} + {audio_path.name}: '{prompt}'", flush=True)
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try:
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audio = _load_audio(audio_path, seq_cfg.sampling_rate, seq_cfg.duration)
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# Audio → latent via VAE (float32: mel_converter/stft require float32)
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# encode_audio is @inference_mode — .clone() exits inference mode
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audio_b = audio.unsqueeze(0).to(device)
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dist = vae_utils.encode_audio(audio_b)
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# VAE outputs [B, latent_dim, T]; generator expects [B, T, latent_dim]
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x1 = dist.mode().clone().transpose(1, 2).cpu()
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# STFT rounding can produce ±1 frame — pad or trim to exact seq length
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tgt = seq_cfg.latent_seq_len
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if x1.shape[1] < tgt:
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x1 = F.pad(x1, (0, 0, 0, tgt - x1.shape[1]))
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elif x1.shape[1] > tgt:
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x1 = x1[:, :tgt, :]
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# Text → CLIP features (reuse already-loaded CLIP from inference model)
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text_clip = feature_utils_orig.encode_text_clip([prompt]).cpu()
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# Pad/trim clip and sync features to fixed seq lengths — clips from
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# shorter videos have fewer frames and would cause stack() to fail
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clip_f = bundle["clip_features"] # [1, N_clip, 1024]
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c_tgt = seq_cfg.clip_seq_len
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if clip_f.shape[1] < c_tgt:
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clip_f = F.pad(clip_f, (0, 0, 0, c_tgt - clip_f.shape[1]))
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elif clip_f.shape[1] > c_tgt:
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clip_f = clip_f[:, :c_tgt, :]
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sync_f = bundle["sync_features"] # [1, N_sync, 768]
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s_tgt = seq_cfg.sync_seq_len
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if sync_f.shape[1] < s_tgt:
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sync_f = F.pad(sync_f, (0, 0, 0, s_tgt - sync_f.shape[1]))
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elif sync_f.shape[1] > s_tgt:
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sync_f = sync_f[:, :s_tgt, :]
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dataset.append((x1, clip_f, sync_f, text_clip))
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except Exception as e:
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print(f" [LoRA Trainer] Warning: failed {npz_path.name}: {e}", flush=True)
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traceback.print_exc()
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pbar_load.update(1)
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# VAE no longer needed — free memory
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del vae_utils
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soft_empty_cache()
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if not dataset:
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raise ValueError("[LoRA Trainer] No clips could be loaded.")
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print(f"[LoRA Trainer] {len(dataset)} clip(s) ready.", flush=True)
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return dataset
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# ---------------------------------------------------------------------------
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# Node
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# ---------------------------------------------------------------------------
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class SelvaLoraTrainer:
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@classmethod
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def INPUT_TYPES(cls):
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return {
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"required": {
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"model": ("SELVA_MODEL",),
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"data_dir": ("STRING", {
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"default": "",
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"tooltip": "Directory containing .npz feature files and paired audio files.",
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}),
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"output_dir": ("STRING", {
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"default": "lora_output",
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"tooltip": "Where to save adapter checkpoints.",
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}),
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"steps": ("INT", {
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"default": 2000, "min": 100, "max": 100000,
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"tooltip": "Total training steps.",
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}),
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"rank": ("INT", {
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"default": 16, "min": 1, "max": 128,
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"tooltip": "LoRA rank. Higher = more capacity, more VRAM. 16 is a safe default.",
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}),
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"lr": ("FLOAT", {
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"default": 1e-4, "min": 1e-6, "max": 1e-2, "step": 1e-6,
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"tooltip": "Learning rate.",
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}),
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},
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"optional": {
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"alpha": ("FLOAT", {
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"default": 0.0, "min": 0.0, "max": 256.0, "step": 0.5,
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"tooltip": "LoRA alpha. 0 = use rank value (scale = 1.0).",
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}),
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"target": ("STRING", {
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"default": "attn.qkv",
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"tooltip": "Space-separated layer name suffixes to wrap. Default targets all QKV projections. Add 'linear1' for post-attention projections.",
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}),
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"batch_size": ("INT", {"default": 4, "min": 1, "max": 32,
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"tooltip": "Number of clips per training step. Higher = more stable gradients, more VRAM."}),
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"warmup_steps": ("INT", {"default": 100, "min": 0, "max": 5000}),
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"grad_accum": ("INT", {"default": 1, "min": 1, "max": 32,
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"tooltip": "Gradient accumulation steps. Usually 1 when batch_size > 1."}),
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"save_every": ("INT", {"default": 500, "min": 50, "max": 10000}),
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"resume_path": ("STRING", {
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"default": "",
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"tooltip": "Path to a step checkpoint (.pt) to resume training from.",
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}),
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"seed": ("INT", {"default": 42}),
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"timestep_mode": (["uniform", "logit_normal", "curriculum"], {
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"default": "uniform",
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"tooltip": "How to sample training timesteps. "
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"uniform: all timesteps equally (matches original MMAudio). "
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"logit_normal: concentrates near t=0.5. "
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"curriculum: logit_normal for first curriculum_switch% of steps then uniform (recommended for small datasets).",
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}),
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"logit_normal_sigma": ("FLOAT", {
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"default": 1.0, "min": 0.1, "max": 3.0, "step": 0.1,
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"tooltip": "Spread of the logit-normal distribution. "
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"1.0 = moderate peak at t=0.5. Higher approaches uniform. "
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"Used with logit_normal and curriculum modes.",
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}),
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"curriculum_switch": ("FLOAT", {
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"default": 0.6, "min": 0.1, "max": 0.9, "step": 0.05,
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"tooltip": "Fraction of steps to run logit_normal before switching to uniform. "
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"0.6 = switch at 60% of total steps. Only used with timestep_mode=curriculum.",
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}),
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"lora_dropout": ("FLOAT", {
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"default": 0.0, "min": 0.0, "max": 0.3, "step": 0.01,
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"tooltip": "Dropout applied to the LoRA path only (not the frozen base weights). "
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"0=disabled. 0.05–0.1 helps regularize on small datasets (arXiv:2404.09610).",
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}),
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"lora_plus_ratio": ("FLOAT", {
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"default": 1.0, "min": 1.0, "max": 32.0, "step": 1.0,
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"tooltip": "LoRA+ LR ratio: lr_B = lr × ratio. "
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"1.0 = standard LoRA. 16.0 = LoRA+ (arXiv:2402.12354).",
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}),
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},
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}
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RETURN_TYPES = ("SELVA_MODEL", "STRING", "IMAGE")
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RETURN_NAMES = ("model", "adapter_path", "loss_curve")
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OUTPUT_TOOLTIPS = (
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"Model with trained LoRA adapter applied — connect directly to Sampler.",
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"Path to adapter_final.pt — use with SelVA LoRA Loader in future sessions.",
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"Training loss curve.",
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)
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FUNCTION = "train"
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CATEGORY = SELVA_CATEGORY
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DESCRIPTION = (
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"Trains a LoRA adapter on a dataset of .npz feature files + paired audio files. "
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"Blocks the queue for the duration of training. "
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"Prepare the dataset with SelVA Feature Extractor (set a name to get numbered .npz files) "
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"and pair each .npz with a clean audio file of the same stem."
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)
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def train(self, model, data_dir, output_dir, steps, rank, lr,
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alpha=0.0, target="attn.qkv", batch_size=4, warmup_steps=100,
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grad_accum=1, save_every=500, resume_path="", seed=42,
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timestep_mode="uniform", logit_normal_sigma=1.0, curriculum_switch=0.6,
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lora_dropout=0.0, lora_plus_ratio=1.0):
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torch.manual_seed(seed)
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random.seed(seed)
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device = get_device()
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dtype = model["dtype"]
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variant = model["variant"]
|
||
mode = model["mode"]
|
||
seq_cfg = model["seq_cfg"]
|
||
feature_utils_orig = model["feature_utils"]
|
||
|
||
data_dir = Path(data_dir.strip())
|
||
|
||
_out_str = output_dir.strip()
|
||
_out_p = Path(_out_str)
|
||
# On Windows a Unix-style path like "/lora_output" is technically absolute
|
||
# (drive-relative) but the user almost certainly meant a subfolder of the
|
||
# ComfyUI output directory. Treat any non-absolute path AND any path whose
|
||
# only "absolute" anchor is a leading slash (no drive letter) as relative to
|
||
# the ComfyUI output folder.
|
||
import sys as _sys
|
||
_unix_style_on_windows = (
|
||
_sys.platform == "win32"
|
||
and _out_p.is_absolute()
|
||
and not _out_p.drive # e.g. Path("/foo").drive == "" on Windows
|
||
)
|
||
if not _out_p.is_absolute() or _unix_style_on_windows:
|
||
_out_p = Path(folder_paths.get_output_directory()) / _out_p.relative_to(_out_p.anchor)
|
||
print(f"[LoRA Trainer] output_dir resolved to: {_out_p}", flush=True)
|
||
output_dir = _out_p
|
||
output_dir.mkdir(parents=True, exist_ok=True)
|
||
|
||
alpha_val = float(alpha) if alpha > 0.0 else float(rank)
|
||
target_suffixes = tuple(target.strip().split())
|
||
|
||
dataset = _prepare_dataset(model, data_dir, device)
|
||
|
||
# ComfyUI executes nodes inside torch.inference_mode(). Inference tensors
|
||
# can't participate in autograd even with enable_grad — disable inference
|
||
# mode entirely so deepcopy, apply_lora, and the training loop all run
|
||
# with a clean autograd context.
|
||
with torch.inference_mode(False), torch.enable_grad():
|
||
r = self._train_inner(
|
||
model, dataset, feature_utils_orig, seq_cfg,
|
||
device, dtype, variant, mode,
|
||
data_dir, output_dir, steps, rank, lr,
|
||
alpha_val, target_suffixes, batch_size, warmup_steps,
|
||
grad_accum, save_every, resume_path, seed,
|
||
timestep_mode, logit_normal_sigma, curriculum_switch,
|
||
lora_dropout, lora_plus_ratio,
|
||
)
|
||
return (r["patched_model"], r["adapter_path"], r["loss_curve"])
|
||
|
||
def _train_inner(
|
||
self, model, dataset, feature_utils_orig, seq_cfg,
|
||
device, dtype, variant, mode,
|
||
data_dir, output_dir, steps, rank, lr,
|
||
alpha_val, target_suffixes, batch_size, warmup_steps,
|
||
grad_accum, save_every, resume_path, seed,
|
||
timestep_mode="uniform", logit_normal_sigma=1.0, curriculum_switch=0.6,
|
||
lora_dropout=0.0, lora_plus_ratio=1.0,
|
||
):
|
||
# --- Prepare generator copy with LoRA ---
|
||
generator = copy.deepcopy(model["generator"]).to(device, dtype)
|
||
|
||
n_lora = apply_lora(generator, rank=rank, alpha=alpha_val,
|
||
target_suffixes=target_suffixes, dropout=lora_dropout)
|
||
if n_lora == 0:
|
||
raise RuntimeError(
|
||
f"[LoRA Trainer] No layers matched target={target_suffixes}. "
|
||
"Check the 'target' field."
|
||
)
|
||
print(f"[LoRA Trainer] Wrapped {n_lora} layers "
|
||
f"(rank={rank}, alpha={alpha_val}, dropout={lora_dropout})", flush=True)
|
||
|
||
for name, p in generator.named_parameters():
|
||
p.requires_grad_("lora_" in name)
|
||
|
||
generator.update_seq_lengths(
|
||
latent_seq_len=seq_cfg.latent_seq_len,
|
||
clip_seq_len=seq_cfg.clip_seq_len,
|
||
sync_seq_len=seq_cfg.sync_seq_len,
|
||
)
|
||
|
||
# --- Optimizer + scheduler ---
|
||
# LoRA+: split A and B into separate param groups with different LRs.
|
||
# ratio=1.0 = standard LoRA (same LR for both). ratio=16 = LoRA+.
|
||
lora_A_params = [p for n, p in generator.named_parameters() if "lora_A" in n and p.requires_grad]
|
||
lora_B_params = [p for n, p in generator.named_parameters() if "lora_B" in n and p.requires_grad]
|
||
optimizer = torch.optim.AdamW([
|
||
{"params": lora_A_params, "lr": lr},
|
||
{"params": lora_B_params, "lr": lr * lora_plus_ratio},
|
||
], weight_decay=1e-2)
|
||
if lora_plus_ratio != 1.0:
|
||
print(f"[LoRA Trainer] LoRA+: lr_A={lr:.2e} lr_B={lr * lora_plus_ratio:.2e}", flush=True)
|
||
|
||
def lr_lambda(s):
|
||
return s / max(1, warmup_steps) if s < warmup_steps else 1.0
|
||
|
||
scheduler = torch.optim.lr_scheduler.LambdaLR(optimizer, lr_lambda)
|
||
fm = FlowMatching(min_sigma=0, inference_mode="euler", num_steps=25)
|
||
|
||
# --- Resume ---
|
||
start_step = 0
|
||
if resume_path.strip():
|
||
ckpt = torch.load(resume_path.strip(), map_location="cpu", weights_only=False)
|
||
if "step" not in ckpt:
|
||
raise ValueError("[LoRA Trainer] Checkpoint has no step info.")
|
||
start_step = ckpt["step"]
|
||
if start_step >= steps:
|
||
raise ValueError(
|
||
f"[LoRA Trainer] Checkpoint already at step {start_step} >= steps {steps}."
|
||
)
|
||
load_lora(generator, ckpt["state_dict"])
|
||
optimizer.load_state_dict(ckpt["optimizer"])
|
||
scheduler.load_state_dict(ckpt["scheduler"])
|
||
print(f"[LoRA Trainer] Resumed from step {start_step}.", flush=True)
|
||
|
||
# --- Training loop ---
|
||
generator.train()
|
||
optimizer.zero_grad()
|
||
|
||
log_interval = 50
|
||
remaining = steps - start_step
|
||
if remaining < log_interval:
|
||
raise ValueError(
|
||
f"[LoRA Trainer] Only {remaining} steps remaining (steps={steps}, "
|
||
f"start_step={start_step}). Need at least {log_interval} steps to "
|
||
"record any loss — increase 'steps' or lower the resume checkpoint."
|
||
)
|
||
pbar_train = comfy.utils.ProgressBar(remaining)
|
||
loss_history = []
|
||
running_loss = 0.0
|
||
grad_norm_history = []
|
||
running_grad_norm = 0.0
|
||
grad_norm_count = 0
|
||
|
||
meta = {
|
||
"variant": variant,
|
||
"rank": rank,
|
||
"alpha": alpha_val,
|
||
"target": list(target_suffixes),
|
||
"steps": steps,
|
||
"timestep_mode": timestep_mode,
|
||
"logit_normal_sigma": logit_normal_sigma,
|
||
"curriculum_switch": curriculum_switch,
|
||
"lora_dropout": lora_dropout,
|
||
"lora_plus_ratio": lora_plus_ratio,
|
||
}
|
||
|
||
# For curriculum mode: compute the step at which we switch from logit_normal to uniform
|
||
curriculum_switch_step = start_step + int((steps - start_step) * curriculum_switch)
|
||
_curriculum_switched = False
|
||
|
||
print(f"\n[LoRA Trainer] Training {remaining} steps "
|
||
f"(step {start_step + 1} → {steps}, batch_size={batch_size}, "
|
||
f"timestep_mode={timestep_mode})\n", flush=True)
|
||
|
||
last_step = start_step
|
||
completed = False
|
||
try:
|
||
for step in range(start_step + 1, steps + 1):
|
||
batch = random.choices(dataset, k=batch_size)
|
||
x1_list, clip_list, sync_list, text_list = zip(*batch)
|
||
|
||
x1 = torch.stack([x.squeeze(0) for x in x1_list]).to(device, dtype)
|
||
clip_f = torch.stack([x.squeeze(0) for x in clip_list]).to(device, dtype)
|
||
sync_f = torch.stack([x.squeeze(0) for x in sync_list]).to(device, dtype)
|
||
text_clip = torch.stack([x.squeeze(0) for x in text_list]).to(device, dtype)
|
||
|
||
generator.normalize(x1)
|
||
|
||
if timestep_mode == "logit_normal" or (
|
||
timestep_mode == "curriculum" and step <= curriculum_switch_step
|
||
):
|
||
u = torch.randn(batch_size, device=device, dtype=dtype) * logit_normal_sigma
|
||
t = torch.sigmoid(u)
|
||
else:
|
||
t = torch.rand(batch_size, device=device, dtype=dtype)
|
||
|
||
if timestep_mode == "curriculum" and step == curriculum_switch_step + 1 and not _curriculum_switched:
|
||
print(f"[LoRA Trainer] Curriculum switch: logit_normal → uniform at step {step}", flush=True)
|
||
_curriculum_switched = True
|
||
x0 = torch.randn_like(x1)
|
||
xt = fm.get_conditional_flow(x0, x1, t)
|
||
|
||
v_pred = generator.forward(xt, clip_f, sync_f, text_clip, t)
|
||
loss = fm.loss(v_pred, x0, x1).mean() / grad_accum
|
||
loss.backward()
|
||
running_loss += loss.item() * grad_accum
|
||
|
||
if step % grad_accum == 0:
|
||
grad_norm = torch.nn.utils.clip_grad_norm_(
|
||
lora_A_params + lora_B_params, max_norm=1.0
|
||
).item()
|
||
running_grad_norm += grad_norm
|
||
grad_norm_count += 1
|
||
optimizer.step()
|
||
scheduler.step()
|
||
optimizer.zero_grad()
|
||
|
||
if step % log_interval == 0:
|
||
avg = running_loss / log_interval
|
||
loss_history.append(avg)
|
||
# grad_norm_count can be 0 when grad_accum > log_interval
|
||
# (no optimizer step fired in this interval yet)
|
||
if grad_norm_count > 0:
|
||
avg_gnorm = running_grad_norm / grad_norm_count
|
||
grad_norm_history.append(round(avg_gnorm, 6))
|
||
gnorm_str = f" grad_norm={avg_gnorm:.4f}"
|
||
else:
|
||
grad_norm_history.append(None)
|
||
gnorm_str = ""
|
||
lr_now = scheduler.get_last_lr()[0]
|
||
print(f"[LoRA Trainer] step {step:5d}/{steps} "
|
||
f"loss={avg:.4f}{gnorm_str} "
|
||
f"lr={lr_now:.2e} bs={batch_size}", flush=True)
|
||
running_loss = 0.0
|
||
running_grad_norm = 0.0
|
||
grad_norm_count = 0
|
||
|
||
# Live preview: send updated loss curve to ComfyUI frontend
|
||
preview_img = _draw_loss_curve(loss_history, log_interval, start_step,
|
||
smoothed=_smooth_losses(loss_history))
|
||
pbar_train.update_absolute(
|
||
step - start_step, remaining, ("JPEG", preview_img, 800)
|
||
)
|
||
|
||
if step % save_every == 0 or step == steps:
|
||
ckpt_path = output_dir / f"adapter_step{step:05d}.pt"
|
||
torch.save({
|
||
"state_dict": get_lora_state_dict(generator),
|
||
"optimizer": optimizer.state_dict(),
|
||
"scheduler": scheduler.state_dict(),
|
||
"step": step,
|
||
"meta": meta,
|
||
}, ckpt_path)
|
||
print(f"[LoRA Trainer] Saved {ckpt_path}", flush=True)
|
||
|
||
# Save a quick eval sample in samples/ subfolder
|
||
samples_dir = output_dir / "samples"
|
||
samples_dir.mkdir(exist_ok=True)
|
||
wav, sr = _eval_sample(generator, feature_utils_orig,
|
||
dataset, seq_cfg, device, dtype, seed=seed)
|
||
if wav is not None:
|
||
wav_path = samples_dir / f"step_{step:05d}.wav"
|
||
try:
|
||
torchaudio.save(str(wav_path), wav, sr)
|
||
except RuntimeError:
|
||
import soundfile as sf
|
||
sf.write(str(wav_path), wav.squeeze(0).numpy(), sr)
|
||
print(f"[LoRA Trainer] Sample saved: {wav_path}", flush=True)
|
||
|
||
last_step = step
|
||
pbar_train.update(1)
|
||
|
||
completed = True
|
||
|
||
finally:
|
||
# Save adapter and loss curves whether training completed or was cancelled.
|
||
# Skip if we never completed a single step (nothing useful to save).
|
||
if loss_history:
|
||
if completed:
|
||
# Normal completion — use adapter_final.pt (increment if exists)
|
||
final_path = output_dir / "adapter_final.pt"
|
||
if final_path.exists():
|
||
i = 1
|
||
while (output_dir / f"adapter_final_{i:03d}.pt").exists():
|
||
i += 1
|
||
final_path = output_dir / f"adapter_final_{i:03d}.pt"
|
||
label = "Done"
|
||
else:
|
||
# Cancelled — include the step number so the file is useful for resume
|
||
final_path = output_dir / f"adapter_cancelled_step{last_step:05d}.pt"
|
||
label = f"Cancelled at step {last_step}"
|
||
|
||
torch.save({"state_dict": get_lora_state_dict(generator), "meta": meta}, final_path)
|
||
(output_dir / "meta.json").write_text(json.dumps(meta, indent=2))
|
||
print(f"\n[LoRA Trainer] {label}. Adapter saved to {final_path}", flush=True)
|
||
|
||
smoothed = _smooth_losses(loss_history)
|
||
raw_img = _draw_loss_curve(loss_history, log_interval, start_step)
|
||
smoothed_img = _draw_loss_curve(loss_history, log_interval, start_step,
|
||
smoothed=smoothed)
|
||
raw_img.save(str(output_dir / "loss_raw.png"))
|
||
smoothed_img.save(str(output_dir / "loss_smoothed.png"))
|
||
print(f"[LoRA Trainer] Loss curves saved to {output_dir}", flush=True)
|
||
|
||
# Reached only on normal completion (exception re-raises past this point)
|
||
generator.eval()
|
||
generator.to(next(model["generator"].parameters()).device)
|
||
patched = {**model, "generator": generator}
|
||
|
||
loss_curve = _pil_to_tensor(smoothed_img)
|
||
return {
|
||
"patched_model": patched,
|
||
"adapter_path": str(final_path),
|
||
"loss_curve": loss_curve,
|
||
"loss_history": loss_history,
|
||
"grad_norm_history": grad_norm_history,
|
||
"start_step": start_step,
|
||
"meta": meta,
|
||
"completed": True,
|
||
}
|