SISU/training_utils.py

165 lines
6.7 KiB
Python

import torch
import torch.nn as nn
import torch.optim as optim
import torchaudio
import torchaudio.transforms as T
def gpu_mfcc_loss(mfcc_transform, y_true, y_pred):
mfccs_true = mfcc_transform(y_true)
mfccs_pred = mfcc_transform(y_pred)
min_len = min(mfccs_true.shape[2], mfccs_pred.shape[2])
mfccs_true = mfccs_true[:, :, :min_len]
mfccs_pred = mfccs_pred[:, :, :min_len]
loss = torch.mean((mfccs_true - mfccs_pred)**2)
return loss
def mel_spectrogram_l1_loss(mel_transform: T.MelSpectrogram, y_true: torch.Tensor, y_pred: torch.Tensor) -> torch.Tensor:
mel_spec_true = mel_transform(y_true)
mel_spec_pred = mel_transform(y_pred)
# Ensure same time dimension length (due to potential framing differences)
min_len = min(mel_spec_true.shape[-1], mel_spec_pred.shape[-1])
mel_spec_true = mel_spec_true[..., :min_len]
mel_spec_pred = mel_spec_pred[..., :min_len]
# L1 Loss (Mean Absolute Error)
loss = torch.mean(torch.abs(mel_spec_true - mel_spec_pred))
return loss
def mel_spectrogram_l2_loss(mel_transform: T.MelSpectrogram, y_true: torch.Tensor, y_pred: torch.Tensor) -> torch.Tensor:
mel_spec_true = mel_transform(y_true)
mel_spec_pred = mel_transform(y_pred)
min_len = min(mel_spec_true.shape[-1], mel_spec_pred.shape[-1])
mel_spec_true = mel_spec_true[..., :min_len]
mel_spec_pred = mel_spec_pred[..., :min_len]
# L2 Loss (Mean Squared Error)
loss = torch.mean((mel_spec_true - mel_spec_pred)**2)
return loss
def log_stft_magnitude_loss(stft_transform: T.Spectrogram, y_true: torch.Tensor, y_pred: torch.Tensor, eps: float = 1e-7) -> torch.Tensor:
stft_mag_true = stft_transform(y_true)
stft_mag_pred = stft_transform(y_pred)
min_len = min(stft_mag_true.shape[-1], stft_mag_pred.shape[-1])
stft_mag_true = stft_mag_true[..., :min_len]
stft_mag_pred = stft_mag_pred[..., :min_len]
# Log Magnitude L1 Loss
loss = torch.mean(torch.abs(torch.log(stft_mag_true + eps) - torch.log(stft_mag_pred + eps)))
return loss
def spectral_convergence_loss(stft_transform: T.Spectrogram, y_true: torch.Tensor, y_pred: torch.Tensor, eps: float = 1e-7) -> torch.Tensor:
stft_mag_true = stft_transform(y_true)
stft_mag_pred = stft_transform(y_pred)
min_len = min(stft_mag_true.shape[-1], stft_mag_pred.shape[-1])
stft_mag_true = stft_mag_true[..., :min_len]
stft_mag_pred = stft_mag_pred[..., :min_len]
# Calculate Frobenius norms and the loss
# Ensure norms are calculated over frequency and time dims ([..., freq, time])
norm_true = torch.linalg.norm(stft_mag_true, ord='fro', dim=(-2, -1))
norm_diff = torch.linalg.norm(stft_mag_true - stft_mag_pred, ord='fro', dim=(-2, -1))
# Average loss over the batch
loss = torch.mean(norm_diff / (norm_true + eps))
return loss
def discriminator_train(high_quality, low_quality, real_labels, fake_labels, discriminator, generator, criterion, optimizer):
optimizer.zero_grad()
# Forward pass for real samples
discriminator_decision_from_real = discriminator(high_quality[0])
d_loss_real = criterion(discriminator_decision_from_real, real_labels)
# Forward pass for fake samples (from generator output)
with torch.no_grad(): # Detach generator output within no_grad context
generator_output = generator(low_quality[0])
discriminator_decision_from_fake = discriminator(generator_output) # No need to detach again if inside no_grad
d_loss_fake = criterion(discriminator_decision_from_fake, fake_labels.expand_as(discriminator_decision_from_fake))
# Combine real and fake losses
d_loss = (d_loss_real + d_loss_fake) / 2.0
# Backward pass and optimization
d_loss.backward()
# Optional: Gradient Clipping (can be helpful)
# nn.utils.clip_grad_norm_(discriminator.parameters(), max_norm=1.0) # Gradient Clipping
optimizer.step()
return d_loss
def generator_train(
low_quality,
high_quality,
real_labels,
generator,
discriminator,
adv_criterion, # Criterion for adversarial loss (e.g., BCEWithLogitsLoss)
g_optimizer,
device,
# --- Pass necessary transforms and loss weights ---
mel_transform: T.MelSpectrogram, # Example: Pass Mel transform
# stft_transform: T.Spectrogram, # Pass STFT transform if using STFT losses
# mfcc_transform: T.MFCC, # Pass MFCC transform if using MFCC loss
lambda_adv: float = 1.0, # Weight for adversarial loss
lambda_mel_l1: float = 10.0, # Example: Weight for Mel L1 loss
# lambda_log_stft: float = 0.0, # Set weights > 0 for losses you want to use
# lambda_mfcc: float = 0.0
):
g_optimizer.zero_grad()
# 1. Generate high-quality audio from low-quality input
generator_output = generator(low_quality[0])
# 2. Calculate Adversarial Loss (Generator tries to fool discriminator)
discriminator_decision = discriminator(generator_output)
# Generator wants discriminator to output "real" labels for its fakes
adversarial_loss = adv_criterion(discriminator_decision, real_labels.expand_as(discriminator_decision))
# 3. Calculate Reconstruction/Spectrogram Loss(es)
# --- Choose and calculate the losses you want to include ---
mel_l1 = 0.0
# log_stft_l1 = 0.0
# mfcc_l = 0.0
# Calculate Mel L1 Loss if weight is positive
if lambda_mel_l1 > 0:
mel_l1 = mel_spectrogram_l1_loss(mel_transform, high_quality[0], generator_output)
# # Calculate Log STFT L1 Loss if weight is positive
# if lambda_log_stft > 0:
# log_stft_l1 = log_stft_magnitude_loss(stft_transform, hq_audio, generator_output)
# # Calculate MFCC Loss if weight is positive
# if lambda_mfcc > 0:
# mfcc_l = gpu_mfcc_loss(mfcc_transform, hq_audio, generator_output)
# --- End of Loss Calculation Choices ---
# 4. Combine Losses
# Make sure calculated losses are tensors even if weights are 0 initially
# (or handle appropriately in the sum)
mel_l1_tensor = torch.tensor(mel_l1, device=device) if isinstance(mel_l1, float) else mel_l1
# log_stft_l1_tensor = torch.tensor(log_stft_l1, device=device) if isinstance(log_stft_l1, float) else log_stft_l1
# mfcc_l_tensor = torch.tensor(mfcc_l, device=device) if isinstance(mfcc_l, float) else mfcc_l
combined_loss = (lambda_adv * adversarial_loss) + \
(lambda_mel_l1 * mel_l1_tensor)
# + (lambda_log_stft * log_stft_l1_tensor) \
# + (lambda_mfcc * mfcc_l_tensor)
# 5. Backward Pass and Optimization
combined_loss.backward()
# Optional: Gradient Clipping
# nn.utils.clip_grad_norm_(generator.parameters(), max_norm=1.0)
g_optimizer.step()
# 6. Return values for logging
return generator_output, combined_loss, adversarial_loss, mel_l1_tensor