uvr5 / demucs /apply.py
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# Copyright (c) Facebook, Inc. and its affiliates.
# All rights reserved.
#
# This source code is licensed under the license found in the
# LICENSE file in the root directory of this source tree.
"""
Code to apply a model to a mix. It will handle chunking with overlaps and
inteprolation between chunks, as well as the "shift trick".
"""
from concurrent.futures import ThreadPoolExecutor
import random
import typing as tp
from multiprocessing import Process,Queue,Pipe
import torch as th
from torch import nn
from torch.nn import functional as F
import tqdm
import tkinter as tk
from .demucs import Demucs
from .hdemucs import HDemucs
from .utils import center_trim, DummyPoolExecutor
Model = tp.Union[Demucs, HDemucs]
progress_bar_num = 0
class BagOfModels(nn.Module):
def __init__(self, models: tp.List[Model],
weights: tp.Optional[tp.List[tp.List[float]]] = None,
segment: tp.Optional[float] = None):
"""
Represents a bag of models with specific weights.
You should call `apply_model` rather than calling directly the forward here for
optimal performance.
Args:
models (list[nn.Module]): list of Demucs/HDemucs models.
weights (list[list[float]]): list of weights. If None, assumed to
be all ones, otherwise it should be a list of N list (N number of models),
each containing S floats (S number of sources).
segment (None or float): overrides the `segment` attribute of each model
(this is performed inplace, be careful if you reuse the models passed).
"""
super().__init__()
assert len(models) > 0
first = models[0]
for other in models:
assert other.sources == first.sources
assert other.samplerate == first.samplerate
assert other.audio_channels == first.audio_channels
if segment is not None:
other.segment = segment
self.audio_channels = first.audio_channels
self.samplerate = first.samplerate
self.sources = first.sources
self.models = nn.ModuleList(models)
if weights is None:
weights = [[1. for _ in first.sources] for _ in models]
else:
assert len(weights) == len(models)
for weight in weights:
assert len(weight) == len(first.sources)
self.weights = weights
def forward(self, x):
raise NotImplementedError("Call `apply_model` on this.")
class TensorChunk:
def __init__(self, tensor, offset=0, length=None):
total_length = tensor.shape[-1]
assert offset >= 0
assert offset < total_length
if length is None:
length = total_length - offset
else:
length = min(total_length - offset, length)
if isinstance(tensor, TensorChunk):
self.tensor = tensor.tensor
self.offset = offset + tensor.offset
else:
self.tensor = tensor
self.offset = offset
self.length = length
self.device = tensor.device
@property
def shape(self):
shape = list(self.tensor.shape)
shape[-1] = self.length
return shape
def padded(self, target_length):
delta = target_length - self.length
total_length = self.tensor.shape[-1]
assert delta >= 0
start = self.offset - delta // 2
end = start + target_length
correct_start = max(0, start)
correct_end = min(total_length, end)
pad_left = correct_start - start
pad_right = end - correct_end
out = F.pad(self.tensor[..., correct_start:correct_end], (pad_left, pad_right))
assert out.shape[-1] == target_length
return out
def tensor_chunk(tensor_or_chunk):
if isinstance(tensor_or_chunk, TensorChunk):
return tensor_or_chunk
else:
assert isinstance(tensor_or_chunk, th.Tensor)
return TensorChunk(tensor_or_chunk)
def apply_model(model,
mix,
shifts=1,
split=True,
overlap=0.25,
transition_power=1.,
static_shifts=1,
set_progress_bar=None,
device=None,
progress=False,
num_workers=0,
pool=None):
"""
Apply model to a given mixture.
Args:
shifts (int): if > 0, will shift in time `mix` by a random amount between 0 and 0.5 sec
and apply the oppositve shift to the output. This is repeated `shifts` time and
all predictions are averaged. This effectively makes the model time equivariant
and improves SDR by up to 0.2 points.
split (bool): if True, the input will be broken down in 8 seconds extracts
and predictions will be performed individually on each and concatenated.
Useful for model with large memory footprint like Tasnet.
progress (bool): if True, show a progress bar (requires split=True)
device (torch.device, str, or None): if provided, device on which to
execute the computation, otherwise `mix.device` is assumed.
When `device` is different from `mix.device`, only local computations will
be on `device`, while the entire tracks will be stored on `mix.device`.
"""
global fut_length
global bag_num
global prog_bar
if device is None:
device = mix.device
else:
device = th.device(device)
if pool is None:
if num_workers > 0 and device.type == 'cpu':
pool = ThreadPoolExecutor(num_workers)
else:
pool = DummyPoolExecutor()
kwargs = {
'shifts': shifts,
'split': split,
'overlap': overlap,
'transition_power': transition_power,
'progress': progress,
'device': device,
'pool': pool,
'set_progress_bar': set_progress_bar,
'static_shifts': static_shifts,
}
if isinstance(model, BagOfModels):
# Special treatment for bag of model.
# We explicitely apply multiple times `apply_model` so that the random shifts
# are different for each model.
estimates = 0
totals = [0] * len(model.sources)
bag_num = len(model.models)
fut_length = 0
prog_bar = 0
current_model = 0 #(bag_num + 1)
for sub_model, weight in zip(model.models, model.weights):
original_model_device = next(iter(sub_model.parameters())).device
sub_model.to(device)
fut_length += fut_length
current_model += 1
out = apply_model(sub_model, mix, **kwargs)
sub_model.to(original_model_device)
for k, inst_weight in enumerate(weight):
out[:, k, :, :] *= inst_weight
totals[k] += inst_weight
estimates += out
del out
for k in range(estimates.shape[1]):
estimates[:, k, :, :] /= totals[k]
return estimates
model.to(device)
model.eval()
assert transition_power >= 1, "transition_power < 1 leads to weird behavior."
batch, channels, length = mix.shape
if shifts:
kwargs['shifts'] = 0
max_shift = int(0.5 * model.samplerate)
mix = tensor_chunk(mix)
padded_mix = mix.padded(length + 2 * max_shift)
out = 0
for _ in range(shifts):
offset = random.randint(0, max_shift)
shifted = TensorChunk(padded_mix, offset, length + max_shift - offset)
shifted_out = apply_model(model, shifted, **kwargs)
out += shifted_out[..., max_shift - offset:]
out /= shifts
return out
elif split:
kwargs['split'] = False
out = th.zeros(batch, len(model.sources), channels, length, device=mix.device)
sum_weight = th.zeros(length, device=mix.device)
segment = int(model.samplerate * model.segment)
stride = int((1 - overlap) * segment)
offsets = range(0, length, stride)
scale = float(format(stride / model.samplerate, ".2f"))
# We start from a triangle shaped weight, with maximal weight in the middle
# of the segment. Then we normalize and take to the power `transition_power`.
# Large values of transition power will lead to sharper transitions.
weight = th.cat([th.arange(1, segment // 2 + 1, device=device),
th.arange(segment - segment // 2, 0, -1, device=device)])
assert len(weight) == segment
# If the overlap < 50%, this will translate to linear transition when
# transition_power is 1.
weight = (weight / weight.max())**transition_power
futures = []
for offset in offsets:
chunk = TensorChunk(mix, offset, segment)
future = pool.submit(apply_model, model, chunk, **kwargs)
futures.append((future, offset))
offset += segment
if progress:
futures = tqdm.tqdm(futures, unit_scale=scale, ncols=120, unit='seconds')
for future, offset in futures:
if set_progress_bar:
fut_length = (len(futures) * bag_num * static_shifts)
prog_bar += 1
set_progress_bar(0.1, (0.8/fut_length*prog_bar))
chunk_out = future.result()
chunk_length = chunk_out.shape[-1]
out[..., offset:offset + segment] += (weight[:chunk_length] * chunk_out).to(mix.device)
sum_weight[offset:offset + segment] += weight[:chunk_length].to(mix.device)
assert sum_weight.min() > 0
out /= sum_weight
return out
else:
if hasattr(model, 'valid_length'):
valid_length = model.valid_length(length)
else:
valid_length = length
mix = tensor_chunk(mix)
padded_mix = mix.padded(valid_length).to(device)
with th.no_grad():
out = model(padded_mix)
return center_trim(out, length)
def demucs_segments(demucs_segment, demucs_model):
if demucs_segment == 'Default':
segment = None
if isinstance(demucs_model, BagOfModels):
if segment is not None:
for sub in demucs_model.models:
sub.segment = segment
else:
if segment is not None:
sub.segment = segment
else:
try:
segment = int(demucs_segment)
if isinstance(demucs_model, BagOfModels):
if segment is not None:
for sub in demucs_model.models:
sub.segment = segment
else:
if segment is not None:
sub.segment = segment
except:
segment = None
if isinstance(demucs_model, BagOfModels):
if segment is not None:
for sub in demucs_model.models:
sub.segment = segment
else:
if segment is not None:
sub.segment = segment
return demucs_model