Files
Salvador E. Tropea 5bcecd9268 [Demix][Fix] Demucs segments
So now the default is valid for MDX and Demucs
2025-07-08 10:28:45 -03:00

300 lines
13 KiB
Python

# Copyright (c) 2025 Salvador E. Tropea
# Copyright (c) 2025 Instituto Nacional de Tecnología Industrial
# License: GPLv3
# Project: ComfyUI-AudioSeparation
#
# Wrappers for the model and inference
import logging
import math
import torch
# ComfyUI imports
try:
import comfy.utils
with_comfy = True
except Exception:
with_comfy = False
# Local imports
from .stft import stft_chunk_process, stft_get_chunks
from ..db.load_model import load_model
from ..utils.misc import NODES_NAME
from ..utils.torch import model_to_target, get_offload_device
from .demucs_api import apply_model, BagOfModels
logger = logging.getLogger(f"{NODES_NAME}.demixer")
SAMPLE_RATE = 44100
class DemixerGeneric(object):
def __init__(self, d, device, models_dir):
super().__init__()
self.d = d
self.model_run = load_model(d, device, models_dir)
self.device = device
def set_device(self, device):
if device == self.device:
return
self.device = device
if hasattr(self.model_run, "target_device"):
self.model_run = device
# ############################################################################################################################
# MDX-Net
# ############################################################################################################################
def show_inference_parameters(d):
logger.debug("Using inference parameters:")
logger.debug(f" Frequency Bins (n_fft/2): {d['mdx_n_fft_scale_set']//2}")
logger.debug(f" Amplitude Compensation: {d['compensate']}")
class DemixerMDX(DemixerGeneric):
def __init__(self, d, device, models_dir):
super().__init__(d, device, models_dir)
show_inference_parameters(d)
self.sr = SAMPLE_RATE
self.ch = 2
def __call__(self, waveform, segments=None):
if segments is None:
# To make it compatible with Demucs
segments = 1
dim_t = (2 ** self.d['mdx_dim_t_set']) * segments
try:
# --- 1. Normalize input shape to handle both batched and non-batched data ---
if waveform.ndim == 2:
# Input is [C, samples], add a batch dimension to make it [1, C, samples]
logger.debug("Input is not batched. Adding a temporary batch dimension.")
waveform = waveform.unsqueeze(0)
input_was_batched = False
elif waveform.ndim == 3:
# Input is already batched [B, C, samples]
input_was_batched = True
else:
raise ValueError(f"Unsupported waveform shape: {waveform.shape}. Expected 2 or 3 dimensions.")
batch_size = waveform.shape[0]
logger.info("🎛️ Performing demix...")
# Lists to store the separated stems from each item in the batch
list_of_main_stems = []
list_of_complement_stems = []
# ComfyUI progress bar
progress_bar_ui = None
if with_comfy:
chunks = stft_get_chunks(waveform.shape[2], self.d['mdx_n_fft_scale_set'], segment_size=dim_t)
chunks *= batch_size
progress_bar_ui = comfy.utils.ProgressBar(chunks)
# --- 2. Iterate through the batch ---
for i, single_waveform in enumerate(waveform):
# single_waveform has shape [C, samples]
logger.debug(f"Processing item {i+1}/{batch_size}...")
# Process this single waveform
main_wav = stft_chunk_process(single_waveform, self.d, self.model_run, self.device, segment_size=dim_t,
progress_bar_ui=progress_bar_ui)
complement_wav = single_waveform - main_wav
# Add the results to our lists
list_of_main_stems.append(main_wav)
list_of_complement_stems.append(complement_wav)
# --- 3. Stack the results into single batch tensors ---
# torch.stack creates a new dimension (the batch dimension) from a list of tensors
stacked_main_stems = torch.stack(list_of_main_stems, dim=0)
stacked_complement_stems = torch.stack(list_of_complement_stems, dim=0)
# Both will now have shape [B, C, samples]
# --- 4. Denormalize output shape if original input was not batched ---
if not input_was_batched:
logger.debug("Squeezing batch dimension from output to match non-batched input.")
stacked_main_stems = stacked_main_stems.squeeze(0)
stacked_complement_stems = stacked_complement_stems.squeeze(0)
return [{'waveform': stacked_main_stems, 'sample_rate': SAMPLE_RATE, 'stem': self.d['primary_stem']},
{'waveform': stacked_complement_stems, 'sample_rate': SAMPLE_RATE, 'stem': 'Complement'}]
except Exception as e:
logger.error(f"Error during separation: {str(e)}")
raise e
# ############################################################################################################################
# Demucs
# ############################################################################################################################
def get_steps_for_demucs(model, wav, segment, shifts, overlap):
segment = segment or model.segment
segment_length = int(model.samplerate * segment)
stride = int((1 - overlap) * segment_length)
return math.ceil(wav.shape[-1] / stride) * (shifts + 1)
class DemixerDemucs(DemixerGeneric):
def __init__(self, d, device, models_dir):
super().__init__(d, device, models_dir)
self.sr = self.model_run.samplerate
# Demucs code will move the model to and from the device
# The advantage is that it will be do it for the sub_models
# So here we keep it offloaded and tell Demucs code to do the work
self.model_run.target_device = get_offload_device()
def get_steps(self, wav, segment, shifts, overlap):
""" Tries to figure out how much steps we will need for inference """
if isinstance(self.model_run, BagOfModels):
total = 0
for sub_model in self.model_run.models:
steps = get_steps_for_demucs(sub_model, wav, segment, shifts, overlap)
total += steps
logger.debug(f"- Steps {steps}")
logger.debug(f"Total steps {total}")
return total
steps = get_steps_for_demucs(self.model_run, wav, segment, shifts, overlap)
logger.debug(f"Steps {steps}")
return steps
def demucs_callback(self, v):
self.comfy_progress_bar.update(1)
def __call__(self, waveform_tensor, segment=None, shifts=0, overlap=0.25):
try:
# --- 1. Normalize input shape to handle both batched and non-batched data ---
if waveform_tensor.ndim == 2:
# Input is [C, samples], add a batch dimension to make it [1, C, samples]
logger.debug("Input is not batched. Adding a temporary batch dimension.")
waveform_tensor = waveform_tensor.unsqueeze(0)
input_was_batched = False
elif waveform_tensor.ndim == 3:
# Input is already batched [B, C, samples]
input_was_batched = True
else:
raise ValueError(f"Unsupported waveform shape: {waveform_tensor.shape}. Expected 2 or 3 dimensions.")
batch_size = waveform_tensor.shape[0]
logger.info("🎛️ Performing demix...")
model = self.model_run
input_tensor_on_device = waveform_tensor.to(self.device)
# Determine the segment size
# 1. User selection
# 2. Value in the config
# 3. Auto: from each model (when None)
forced_segment = segment
if forced_segment is None:
forced_segment = self.model_run.config_segment
if forced_segment:
logger.debug(f"Using model provided segment size {forced_segment} s")
else:
logger.debug("Using default segment size")
forced_segment = None
else:
logger.debug(f"Using user provided segment size {forced_segment} s")
if with_comfy:
comfy_progress_bar = comfy.utils.ProgressBar(self.get_steps(waveform_tensor, forced_segment, shifts, overlap))
with model_to_target(model):
separated_tensors = apply_model(
model,
input_tensor_on_device,
device=self.device,
segment=forced_segment,
shifts=shifts + 1, # Shifts 0 is disabled, 1 is just one pass, 2 is 2 passes
overlap=overlap,
split=True, # Enable chunking
progress=True, # Show a progress bar in the console
callback=lambda x: (x.get('state') == 'end') and comfy_progress_bar.update(1) if with_comfy else None,
)
# Move the final result tensor back to the CPU before creating the output dicts.
# This is good practice to free up VRAM for subsequent nodes.
separated_tensors = separated_tensors.cpu()
assert batch_size == separated_tensors.shape[0]
# The output is [batch, sources, channels, samples].
# But we will separate the stems and return a batch for each stem, so we need
# [sources, batch, channels, samples].
separated_sources = separated_tensors.permute(1, 0, 2, 3)
# The model object tells us the names of the stems it produced
model_stems = model.sources.copy()
# UVR model is a 2 stems model with vocals and non_vocals, map it gracefully
if model_stems[1] == 'non_vocals':
model_stems[1] = 'other'
logger.debug(f"Model produced {len(model_stems)} stems: {model_stems}")
# Create a dictionary mapping the stem name to the audio tensor
output_map = dict(zip(model_stems, separated_sources))
# --- Silent audio for missing stems
reference_tensor = None
# Find the first valid tensor from our output to use as a shape reference
for tensor in output_map.values():
if tensor is not None and isinstance(tensor, torch.Tensor):
reference_tensor = tensor
break
# Determine the shape and sample rate for our silent audio fallback
if reference_tensor is not None:
# If we have a successful stem, use its properties
ref_batch_size, ref_channels, ref_samples = reference_tensor.shape
else:
# EDGE CASE: All stems failed. Fall back to the input audio's properties.
logger.warning("All stems failed. Using input audio shape for silence.")
# input_audio['waveform'] has shape [batch, channels, samples]
ref_batch_size, ref_channels, ref_samples = waveform_tensor.shape
# ---
# --- Gracefully create the 6 outputs ---
# Iterate through our fixed RETURN_NAMES and get the corresponding tensor.
# If a stem name doesn't exist in our output_map (e.g., 'guitar' for a 4-stem model),
# the .get() method will return None, which ComfyUI handles correctly.
final_outputs = []
for stem_name in ("vocals", "drums", "bass", "other", "guitar", "piano"):
output_tensor = output_map.get(stem_name, None)
# If the stem was produced, wrap it back into an AUDIO dict.
# If not, append None. ComfyUI handles None outputs correctly.
if output_tensor is not None:
if not input_was_batched:
output_tensor = output_tensor.squeeze(0)
output_dict = {
"waveform": output_tensor,
"sample_rate": model.samplerate,
"stem": stem_name.capitalize()
}
final_outputs.append(output_dict)
else:
logger.debug(f"Stem '{stem_name}' not produced by model. Returning silence.")
# Create a silent tensor with the correct shape, device, and dtype
silent_waveform = torch.zeros(ref_batch_size, ref_channels, ref_samples, dtype=torch.float32)
# Wrap the silent tensor in the ComfyUI AUDIO dictionary format
silent_dict = {
"waveform": silent_waveform,
"sample_rate": model.samplerate,
"stem": stem_name.capitalize()
}
final_outputs.append(silent_dict)
return tuple(final_outputs)
except Exception as e:
logger.error(f"Error during separation: {str(e)}")
raise e
def get_demixer(d, device, models_dir):
model_t = d['model_t'].lower()
if model_t == "mdx":
return DemixerMDX(d, device, models_dir)
elif model_t == "demucs":
return DemixerDemucs(d, device, models_dir)
msg = f"Unknown model type `{model_t}`"
logger.error(msg)
raise ValueError(msg)