forked from mrq/DL-Art-School
classical unet for music
This commit is contained in:
James Betker
parent
d3a60633a3
commit
9d8c2bddb1
757
codes/models/audio/music/unet_diffusion_music_codes.py
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757
codes/models/audio/music/unet_diffusion_music_codes.py
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from abc import abstractmethod
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import math
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import numpy as np
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import torch
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import torch as th
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import torch.nn as nn
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import torch.nn.functional as F
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import torchvision # For debugging, not actually used.
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from x_transformers.x_transformers import RelativePositionBias
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from models.audio.music.music_quantizer import MusicQuantizer
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from models.diffusion.fp16_util import convert_module_to_f16, convert_module_to_f32
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from models.diffusion.nn import (
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conv_nd,
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linear,
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avg_pool_nd,
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zero_module,
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normalization,
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timestep_embedding,
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)
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from models.lucidrains.x_transformers import Encoder
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from trainer.networks import register_model
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from utils.util import checkpoint, print_network
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class TimestepBlock(nn.Module):
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"""
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Any module where forward() takes timestep embeddings as a second argument.
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"""
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@abstractmethod
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def forward(self, x, emb):
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"""
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Apply the module to `x` given `emb` timestep embeddings.
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"""
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class TimestepEmbedSequential(nn.Sequential, TimestepBlock):
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"""
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A sequential module that passes timestep embeddings to the children that
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support it as an extra input.
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"""
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def forward(self, x, emb):
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for layer in self:
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if isinstance(layer, TimestepBlock):
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x = layer(x, emb)
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else:
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x = layer(x)
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return x
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class Upsample(nn.Module):
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"""
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An upsampling layer with an optional convolution.
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:param channels: channels in the inputs and outputs.
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:param use_conv: a bool determining if a convolution is applied.
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:param dims: determines if the signal is 1D, 2D, or 3D. If 3D, then
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upsampling occurs in the inner-two dimensions.
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"""
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def __init__(self, channels, use_conv, dims=2, out_channels=None, factor=None, ksize=3, pad=1):
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super().__init__()
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self.channels = channels
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self.out_channels = out_channels or channels
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self.use_conv = use_conv
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self.dims = dims
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if factor is None:
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if dims == 1:
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self.factor = 4
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else:
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self.factor = 2
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else:
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self.factor = factor
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if use_conv:
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if dims == 1:
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ksize = 5
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pad = 2
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self.conv = conv_nd(dims, self.channels, self.out_channels, ksize, padding=pad)
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def forward(self, x):
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assert x.shape[1] == self.channels
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if self.dims == 3:
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x = F.interpolate(
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x, (x.shape[2], x.shape[3] * 2, x.shape[4] * 2), mode="nearest"
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)
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x = F.interpolate(x, scale_factor=self.factor, mode="nearest")
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if self.use_conv:
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x = self.conv(x)
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return x
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class Downsample(nn.Module):
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"""
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A downsampling layer with an optional convolution.
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:param channels: channels in the inputs and outputs.
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:param use_conv: a bool determining if a convolution is applied.
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:param dims: determines if the signal is 1D, 2D, or 3D. If 3D, then
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downsampling occurs in the inner-two dimensions.
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"""
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def __init__(self, channels, use_conv, dims=2, out_channels=None, factor=None, ksize=None, pad=None):
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super().__init__()
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self.channels = channels
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self.out_channels = out_channels or channels
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self.use_conv = use_conv
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self.dims = dims
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if ksize is None:
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ksize = 3
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pad = 1
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if dims == 1:
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ksize = 5
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pad = 2
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if dims == 1:
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stride = 4
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elif dims == 2:
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stride = 2
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else:
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stride = (1,2,2)
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if factor is not None:
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stride = factor
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if use_conv:
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self.op = conv_nd(
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dims, self.channels, self.out_channels, ksize, stride=stride, padding=pad
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)
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else:
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assert self.channels == self.out_channels
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self.op = avg_pool_nd(dims, kernel_size=stride, stride=stride)
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def forward(self, x):
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assert x.shape[1] == self.channels
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return self.op(x)
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class ResBlock(TimestepBlock):
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"""
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A residual block that can optionally change the number of channels.
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:param channels: the number of input channels.
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:param emb_channels: the number of timestep embedding channels.
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:param dropout: the rate of dropout.
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:param out_channels: if specified, the number of out channels.
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:param use_conv: if True and out_channels is specified, use a spatial
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convolution instead of a smaller 1x1 convolution to change the
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channels in the skip connection.
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:param dims: determines if the signal is 1D, 2D, or 3D.
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:param up: if True, use this block for upsampling.
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:param down: if True, use this block for downsampling.
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"""
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def __init__(
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self,
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channels,
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emb_channels,
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dropout,
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out_channels=None,
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use_conv=False,
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use_scale_shift_norm=False,
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dims=2,
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up=False,
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down=False,
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kernel_size=3,
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):
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super().__init__()
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self.channels = channels
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self.emb_channels = emb_channels
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self.dropout = dropout
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self.out_channels = out_channels or channels
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self.use_conv = use_conv
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self.use_scale_shift_norm = use_scale_shift_norm
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padding = 1 if kernel_size == 3 else (2 if kernel_size == 5 else 0)
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self.in_layers = nn.Sequential(
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normalization(channels),
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nn.SiLU(),
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conv_nd(dims, channels, self.out_channels, kernel_size, padding=padding),
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)
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self.updown = up or down
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if up:
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self.h_upd = Upsample(channels, False, dims)
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self.x_upd = Upsample(channels, False, dims)
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elif down:
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self.h_upd = Downsample(channels, False, dims)
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self.x_upd = Downsample(channels, False, dims)
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else:
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self.h_upd = self.x_upd = nn.Identity()
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self.emb_layers = nn.Sequential(
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nn.SiLU(),
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linear(
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emb_channels,
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2 * self.out_channels if use_scale_shift_norm else self.out_channels,
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),
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)
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self.out_layers = nn.Sequential(
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normalization(self.out_channels),
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nn.SiLU(),
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nn.Dropout(p=dropout),
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zero_module(
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conv_nd(dims, self.out_channels, self.out_channels, kernel_size, padding=padding)
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),
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)
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if self.out_channels == channels:
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self.skip_connection = nn.Identity()
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elif use_conv:
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self.skip_connection = conv_nd(
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dims, channels, self.out_channels, kernel_size, padding=padding
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)
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else:
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self.skip_connection = conv_nd(dims, channels, self.out_channels, 1)
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def forward(self, x, emb):
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"""
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Apply the block to a Tensor, conditioned on a timestep embedding.
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:param x: an [N x C x ...] Tensor of features.
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:param emb: an [N x emb_channels] Tensor of timestep embeddings.
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:return: an [N x C x ...] Tensor of outputs.
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"""
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return checkpoint(
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self._forward, x, emb
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)
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def _forward(self, x, emb):
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if self.updown:
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in_rest, in_conv = self.in_layers[:-1], self.in_layers[-1]
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h = in_rest(x)
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h = self.h_upd(h)
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x = self.x_upd(x)
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h = in_conv(h)
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else:
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h = self.in_layers(x)
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emb_out = self.emb_layers(emb).type(h.dtype)
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while len(emb_out.shape) < len(h.shape):
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emb_out = emb_out[..., None]
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if self.use_scale_shift_norm:
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out_norm, out_rest = self.out_layers[0], self.out_layers[1:]
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scale, shift = th.chunk(emb_out, 2, dim=1)
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h = out_norm(h) * (1 + scale) + shift
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h = out_rest(h)
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else:
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h = h + emb_out
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h = self.out_layers(h)
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return self.skip_connection(x) + h
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class AttentionBlock(nn.Module):
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"""
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An attention block that allows spatial positions to attend to each other.
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Originally ported from here, but adapted to the N-d case.
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https://github.com/hojonathanho/diffusion/blob/1e0dceb3b3495bbe19116a5e1b3596cd0706c543/diffusion_tf/models/unet.py#L66.
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"""
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def __init__(
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self,
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channels,
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num_heads=1,
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num_head_channels=-1,
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use_new_attention_order=False,
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do_checkpoint=True,
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relative_pos_embeddings=False,
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):
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super().__init__()
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self.channels = channels
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self.do_checkpoint = do_checkpoint
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if num_head_channels == -1:
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self.num_heads = num_heads
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else:
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assert (
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channels % num_head_channels == 0
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), f"q,k,v channels {channels} is not divisible by num_head_channels {num_head_channels}"
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self.num_heads = channels // num_head_channels
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self.norm = normalization(channels)
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self.qkv = conv_nd(1, channels, channels * 3, 1)
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if use_new_attention_order:
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# split qkv before split heads
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self.attention = QKVAttention(self.num_heads)
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else:
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# split heads before split qkv
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self.attention = QKVAttentionLegacy(self.num_heads)
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self.proj_out = zero_module(conv_nd(1, channels, channels, 1))
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if relative_pos_embeddings:
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self.relative_pos_embeddings = RelativePositionBias(scale=(channels // self.num_heads) ** .5, causal=False, heads=num_heads, num_buckets=32, max_distance=64)
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else:
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self.relative_pos_embeddings = None
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def forward(self, x, mask=None):
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if self.do_checkpoint:
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return checkpoint(self._forward, x, mask)
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else:
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return self._forward(x, mask)
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def _forward(self, x, mask):
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b, c, *spatial = x.shape
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x = x.reshape(b, c, -1)
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qkv = self.qkv(self.norm(x))
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h = self.attention(qkv, mask, self.relative_pos_embeddings)
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h = self.proj_out(h)
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return (x + h).reshape(b, c, *spatial)
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def count_flops_attn(model, _x, y):
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"""
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A counter for the `thop` package to count the operations in an
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attention operation.
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Meant to be used like:
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macs, params = thop.profile(
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model,
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inputs=(inputs, timestamps),
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custom_ops={QKVAttention: QKVAttention.count_flops},
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)
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"""
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b, c, *spatial = y[0].shape
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num_spatial = int(np.prod(spatial))
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# We perform two matmuls with the same number of ops.
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# The first computes the weight matrix, the second computes
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# the combination of the value vectors.
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matmul_ops = 2 * b * (num_spatial ** 2) * c
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model.total_ops += th.DoubleTensor([matmul_ops])
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class QKVAttentionLegacy(nn.Module):
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"""
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A module which performs QKV attention. Matches legacy QKVAttention + input/ouput heads shaping
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"""
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def __init__(self, n_heads):
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super().__init__()
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self.n_heads = n_heads
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def forward(self, qkv, mask=None, rel_pos=None):
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"""
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Apply QKV attention.
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:param qkv: an [N x (H * 3 * C) x T] tensor of Qs, Ks, and Vs.
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:return: an [N x (H * C) x T] tensor after attention.
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"""
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bs, width, length = qkv.shape
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assert width % (3 * self.n_heads) == 0
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ch = width // (3 * self.n_heads)
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q, k, v = qkv.reshape(bs * self.n_heads, ch * 3, length).split(ch, dim=1)
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scale = 1 / math.sqrt(math.sqrt(ch))
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weight = th.einsum(
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"bct,bcs->bts", q * scale, k * scale
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) # More stable with f16 than dividing afterwards
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if rel_pos is not None:
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weight = rel_pos(weight.reshape(bs, self.n_heads, weight.shape[-2], weight.shape[-1])).reshape(bs * self.n_heads, weight.shape[-2], weight.shape[-1])
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weight = th.softmax(weight.float(), dim=-1).type(weight.dtype)
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if mask is not None:
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# The proper way to do this is to mask before the softmax using -inf, but that doesn't work properly on CPUs.
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mask = mask.repeat(self.n_heads, 1).unsqueeze(1)
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weight = weight * mask
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a = th.einsum("bts,bcs->bct", weight, v)
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return a.reshape(bs, -1, length)
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@staticmethod
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def count_flops(model, _x, y):
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return count_flops_attn(model, _x, y)
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class QKVAttention(nn.Module):
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"""
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A module which performs QKV attention and splits in a different order.
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"""
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def __init__(self, n_heads):
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super().__init__()
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self.n_heads = n_heads
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def forward(self, qkv, mask=None, rel_pos=None):
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"""
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Apply QKV attention.
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:param qkv: an [N x (3 * H * C) x T] tensor of Qs, Ks, and Vs.
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:return: an [N x (H * C) x T] tensor after attention.
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"""
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bs, width, length = qkv.shape
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assert width % (3 * self.n_heads) == 0
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ch = width // (3 * self.n_heads)
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q, k, v = qkv.chunk(3, dim=1)
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scale = 1 / math.sqrt(math.sqrt(ch))
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weight = th.einsum(
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"bct,bcs->bts",
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(q * scale).view(bs * self.n_heads, ch, length),
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(k * scale).view(bs * self.n_heads, ch, length),
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) # More stable with f16 than dividing afterwards
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if rel_pos is not None:
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weight = rel_pos(weight)
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if mask is not None:
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# The proper way to do this is to mask before the softmax using -inf, but that doesn't work properly on CPUs.
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mask = mask.repeat(self.n_heads, 1).unsqueeze(1)
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weight = weight * mask
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weight = th.softmax(weight.float(), dim=-1).type(weight.dtype)
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a = th.einsum("bts,bcs->bct", weight, v.reshape(bs * self.n_heads, ch, length))
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return a.reshape(bs, -1, length)
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@staticmethod
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def count_flops(model, _x, y):
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return count_flops_attn(model, _x, y)
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class UNetMusicModel(nn.Module):
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"""
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The full UNet model with attention and timestep embedding.
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:param in_channels: channels in the input Tensor.
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:param model_channels: base channel count for the model.
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:param out_channels: channels in the output Tensor.
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:param num_res_blocks: number of residual blocks per downsample.
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:param attention_resolutions: a collection of downsample rates at which
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attention will take place. May be a set, list, or tuple.
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For example, if this contains 4, then at 4x downsampling, attention
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will be used.
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:param dropout: the dropout probability.
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:param channel_mult: channel multiplier for each level of the UNet.
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:param conv_resample: if True, use learned convolutions for upsampling and
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downsampling.
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:param dims: determines if the signal is 1D, 2D, or 3D.
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:param num_classes: if specified (as an int), then this model will be
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class-conditional with `num_classes` classes.
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:param num_heads: the number of attention heads in each attention layer.
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:param num_heads_channels: if specified, ignore num_heads and instead use
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a fixed channel width per attention head.
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:param num_heads_upsample: works with num_heads to set a different number
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of heads for upsampling. Deprecated.
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:param use_scale_shift_norm: use a FiLM-like conditioning mechanism.
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:param resblock_updown: use residual blocks for up/downsampling.
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:param use_new_attention_order: use a different attention pattern for potentially
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increased efficiency.
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"""
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def __init__(
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self,
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in_channels,
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input_vec_dim,
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model_channels,
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out_channels,
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num_res_blocks,
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attention_resolutions,
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dropout=0,
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channel_mult=(1, 2, 4, 8),
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conv_resample=True,
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dims=2,
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num_classes=None,
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use_fp16=False,
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num_heads=1,
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num_head_channels=-1,
|
||||
num_heads_upsample=-1,
|
||||
use_scale_shift_norm=False,
|
||||
resblock_updown=False,
|
||||
use_new_attention_order=False,
|
||||
use_raw_y_as_embedding=False,
|
||||
unconditioned_percentage=.1, # This implements a mechanism similar to what is used in classifier-free training.
|
||||
):
|
||||
super().__init__()
|
||||
|
||||
if num_heads_upsample == -1:
|
||||
num_heads_upsample = num_heads
|
||||
|
||||
self.in_channels = in_channels
|
||||
self.model_channels = model_channels
|
||||
self.out_channels = out_channels
|
||||
self.num_res_blocks = num_res_blocks
|
||||
self.attention_resolutions = attention_resolutions
|
||||
self.dropout = dropout
|
||||
self.channel_mult = channel_mult
|
||||
self.conv_resample = conv_resample
|
||||
self.num_classes = num_classes
|
||||
self.dtype = th.float16 if use_fp16 else th.float32
|
||||
self.num_heads = num_heads
|
||||
self.num_head_channels = num_head_channels
|
||||
self.num_heads_upsample = num_heads_upsample
|
||||
self.unconditioned_percentage = unconditioned_percentage
|
||||
|
||||
time_embed_dim = model_channels * 4
|
||||
self.time_embed = nn.Sequential(
|
||||
linear(model_channels, time_embed_dim),
|
||||
nn.SiLU(),
|
||||
linear(time_embed_dim, time_embed_dim),
|
||||
)
|
||||
|
||||
self.input_converter = nn.Linear(input_vec_dim, model_channels)
|
||||
self.code_converter = Encoder(
|
||||
dim=model_channels,
|
||||
depth=4,
|
||||
heads=num_heads,
|
||||
ff_dropout=dropout,
|
||||
attn_dropout=dropout,
|
||||
use_rmsnorm=True,
|
||||
ff_glu=True,
|
||||
rotary_pos_emb=True,
|
||||
zero_init_branch_output=True,
|
||||
ff_mult=1,
|
||||
)
|
||||
self.unconditioned_embedding = nn.Parameter(torch.randn(1,1,model_channels))
|
||||
self.x_processor = conv_nd(dims, in_channels, model_channels, 3, padding=1)
|
||||
|
||||
if self.num_classes is not None:
|
||||
self.label_emb = nn.Embedding(num_classes, time_embed_dim)
|
||||
self.use_raw_y_as_embedding = use_raw_y_as_embedding
|
||||
assert not ((self.num_classes is not None) and use_raw_y_as_embedding) # These are mutually-exclusive.
|
||||
|
||||
self.input_blocks = nn.ModuleList(
|
||||
[
|
||||
TimestepEmbedSequential(
|
||||
conv_nd(dims, model_channels*2, model_channels, 1, padding=0)
|
||||
)
|
||||
]
|
||||
)
|
||||
self._feature_size = model_channels
|
||||
input_block_chans = [model_channels]
|
||||
ch = model_channels
|
||||
ds = 1
|
||||
for level, mult in enumerate(channel_mult):
|
||||
for _ in range(num_res_blocks):
|
||||
layers = [
|
||||
ResBlock(
|
||||
ch,
|
||||
time_embed_dim,
|
||||
dropout,
|
||||
out_channels=mult * model_channels,
|
||||
dims=dims,
|
||||
use_scale_shift_norm=use_scale_shift_norm,
|
||||
)
|
||||
]
|
||||
ch = mult * model_channels
|
||||
if ds in attention_resolutions:
|
||||
layers.append(
|
||||
AttentionBlock(
|
||||
ch,
|
||||
num_heads=num_heads,
|
||||
num_head_channels=num_head_channels,
|
||||
use_new_attention_order=use_new_attention_order,
|
||||
)
|
||||
)
|
||||
self.input_blocks.append(TimestepEmbedSequential(*layers))
|
||||
self._feature_size += ch
|
||||
input_block_chans.append(ch)
|
||||
if level != len(channel_mult) - 1:
|
||||
out_ch = ch
|
||||
self.input_blocks.append(
|
||||
TimestepEmbedSequential(
|
||||
ResBlock(
|
||||
ch,
|
||||
time_embed_dim,
|
||||
dropout,
|
||||
out_channels=out_ch,
|
||||
dims=dims,
|
||||
use_scale_shift_norm=use_scale_shift_norm,
|
||||
down=True,
|
||||
)
|
||||
if resblock_updown
|
||||
else Downsample(
|
||||
ch, conv_resample, dims=dims, out_channels=out_ch
|
||||
)
|
||||
)
|
||||
)
|
||||
ch = out_ch
|
||||
input_block_chans.append(ch)
|
||||
ds *= 2
|
||||
self._feature_size += ch
|
||||
|
||||
self.middle_block = TimestepEmbedSequential(
|
||||
ResBlock(
|
||||
ch,
|
||||
time_embed_dim,
|
||||
dropout,
|
||||
dims=dims,
|
||||
use_scale_shift_norm=use_scale_shift_norm,
|
||||
),
|
||||
AttentionBlock(
|
||||
ch,
|
||||
num_heads=num_heads,
|
||||
num_head_channels=num_head_channels,
|
||||
use_new_attention_order=use_new_attention_order,
|
||||
),
|
||||
ResBlock(
|
||||
ch,
|
||||
time_embed_dim,
|
||||
dropout,
|
||||
dims=dims,
|
||||
use_scale_shift_norm=use_scale_shift_norm,
|
||||
),
|
||||
)
|
||||
self._feature_size += ch
|
||||
|
||||
self.output_blocks = nn.ModuleList([])
|
||||
for level, mult in list(enumerate(channel_mult))[::-1]:
|
||||
for i in range(num_res_blocks + 1):
|
||||
ich = input_block_chans.pop()
|
||||
layers = [
|
||||
ResBlock(
|
||||
ch + ich,
|
||||
time_embed_dim,
|
||||
dropout,
|
||||
out_channels=model_channels * mult,
|
||||
dims=dims,
|
||||
use_scale_shift_norm=use_scale_shift_norm,
|
||||
)
|
||||
]
|
||||
ch = model_channels * mult
|
||||
if ds in attention_resolutions:
|
||||
layers.append(
|
||||
AttentionBlock(
|
||||
ch,
|
||||
num_heads=num_heads_upsample,
|
||||
num_head_channels=num_head_channels,
|
||||
use_new_attention_order=use_new_attention_order,
|
||||
)
|
||||
)
|
||||
if level and i == num_res_blocks:
|
||||
out_ch = ch
|
||||
layers.append(
|
||||
ResBlock(
|
||||
ch,
|
||||
time_embed_dim,
|
||||
dropout,
|
||||
out_channels=out_ch,
|
||||
dims=dims,
|
||||
use_scale_shift_norm=use_scale_shift_norm,
|
||||
up=True,
|
||||
)
|
||||
if resblock_updown
|
||||
else Upsample(ch, conv_resample, dims=dims, out_channels=out_ch)
|
||||
)
|
||||
ds //= 2
|
||||
self.output_blocks.append(TimestepEmbedSequential(*layers))
|
||||
self._feature_size += ch
|
||||
|
||||
self.out = nn.Sequential(
|
||||
normalization(ch),
|
||||
nn.SiLU(),
|
||||
zero_module(conv_nd(dims, model_channels, out_channels, 3, padding=1)),
|
||||
)
|
||||
|
||||
def forward(self, x, timesteps, y, conditioning_free=False):
|
||||
"""
|
||||
Apply the model to an input batch.
|
||||
|
||||
:param x: an [N x C x ...] Tensor of inputs.
|
||||
:param timesteps: a 1-D batch of timesteps.
|
||||
:param y: a batch of guidance latents from a quantizer
|
||||
:return: an [N x C x ...] Tensor of outputs.
|
||||
"""
|
||||
unused_params = []
|
||||
hs = []
|
||||
emb = self.time_embed(timestep_embedding(timesteps, self.model_channels))
|
||||
|
||||
if conditioning_free:
|
||||
expanded_code_emb = self.unconditioned_embedding.repeat(x.shape[0], 1, x.shape[-1])
|
||||
unused_params.extend(list(self.code_converter.parameters()) + list(self.input_converter.parameters()))
|
||||
else:
|
||||
code_emb = self.input_converter(y)
|
||||
if self.training and self.unconditioned_percentage > 0:
|
||||
unconditioned_batches = torch.rand((code_emb.shape[0], 1, 1),
|
||||
device=code_emb.device) < self.unconditioned_percentage
|
||||
code_emb = torch.where(unconditioned_batches, self.unconditioned_embedding.repeat(y.shape[0], 1, 1),
|
||||
code_emb)
|
||||
code_emb = self.code_converter(code_emb)
|
||||
expanded_code_emb = F.interpolate(code_emb.permute(0,2,1), size=x.shape[-1], mode='nearest')
|
||||
|
||||
h = x.type(self.dtype)
|
||||
expanded_code_emb = expanded_code_emb.type(self.dtype)
|
||||
|
||||
h = self.x_processor(h)
|
||||
h = torch.cat([h, expanded_code_emb], dim=1)
|
||||
|
||||
for module in self.input_blocks:
|
||||
h = module(h, emb)
|
||||
hs.append(h)
|
||||
h = self.middle_block(h, emb)
|
||||
for module in self.output_blocks:
|
||||
h = th.cat([h, hs.pop()], dim=1)
|
||||
h = module(h, emb)
|
||||
h = h.type(x.dtype)
|
||||
|
||||
# Involve probabilistic or possibly unused parameters in loss so we don't get DDP errors.
|
||||
extraneous_addition = 0
|
||||
for p in unused_params:
|
||||
extraneous_addition = extraneous_addition + p.mean()
|
||||
h = h + extraneous_addition * 0
|
||||
|
||||
return self.out(h)
|
||||
|
||||
|
||||
class UNetMusicModelWithQuantizer(nn.Module):
|
||||
def __init__(self, freeze_quantizer_until=20000, **kwargs):
|
||||
super().__init__()
|
||||
|
||||
self.internal_step = 0
|
||||
self.freeze_quantizer_until = freeze_quantizer_until
|
||||
self.diff = UNetMusicModel(**kwargs)
|
||||
self.m2v = MusicQuantizer(inp_channels=256, inner_dim=[1024,1024,512], codevector_dim=1024, codebook_size=512, codebook_groups=2)
|
||||
self.m2v.quantizer.temperature = self.m2v.min_gumbel_temperature
|
||||
del self.m2v.up
|
||||
|
||||
def update_for_step(self, step, *args):
|
||||
self.internal_step = step
|
||||
qstep = max(0, self.internal_step - self.freeze_quantizer_until)
|
||||
self.m2v.quantizer.temperature = max(
|
||||
self.m2v.max_gumbel_temperature * self.m2v.gumbel_temperature_decay**qstep,
|
||||
self.m2v.min_gumbel_temperature,
|
||||
)
|
||||
|
||||
def forward(self, x, timesteps, truth_mel, disable_diversity=False, conditioning_free=False):
|
||||
quant_grad_enabled = self.internal_step > self.freeze_quantizer_until
|
||||
with torch.set_grad_enabled(quant_grad_enabled):
|
||||
proj, diversity_loss = self.m2v(truth_mel, return_decoder_latent=True)
|
||||
proj = proj.permute(0,2,1)
|
||||
|
||||
# Make sure this does not cause issues in DDP by explicitly using the parameters for nothing.
|
||||
if not quant_grad_enabled:
|
||||
unused = 0
|
||||
for p in self.m2v.parameters():
|
||||
unused = unused + p.mean() * 0
|
||||
proj = proj + unused
|
||||
diversity_loss = diversity_loss * 0
|
||||
|
||||
diff = self.diff(x, timesteps, proj, conditioning_free=conditioning_free)
|
||||
if disable_diversity:
|
||||
return diff
|
||||
return diff, diversity_loss
|
||||
|
||||
def get_debug_values(self, step, __):
|
||||
if self.m2v.total_codes > 0:
|
||||
return {'histogram_codes': self.m2v.codes[:self.m2v.total_codes]}
|
||||
else:
|
||||
return {}
|
||||
|
||||
|
||||
@register_model
|
||||
def register_unet_diffusion_music_codes(opt_net, opt):
|
||||
return UNetMusicModelWithQuantizer(**opt_net['args'])
|
||||
|
||||
|
||||
if __name__ == '__main__':
|
||||
clip = torch.randn(2, 256, 400)
|
||||
cond = torch.randn(2, 256, 400)
|
||||
ts = torch.LongTensor([600, 600])
|
||||
model = UNetMusicModelWithQuantizer(in_channels=256, out_channels=512, model_channels=512, num_res_blocks=3, input_vec_dim=1024,
|
||||
attention_resolutions=(2,4), channel_mult=(1,2,3), dims=1,
|
||||
use_scale_shift_norm=True, dropout=.1, num_heads=8)
|
||||
print_network(model)
|
||||
model(clip, ts, cond)
|
||||
|
||||
Loading…
Reference in New Issue
Block a user