Upload bs_roformer.py

bs_roformer.py

@@ -0,0 +1,683 @@
+from functools import partial
+
+import torch
+from torch import nn, einsum, Tensor
+from torch.nn import Module, ModuleList
+import torch.nn.functional as F
+
+from models.bs_roformer.attend import Attend
+try:
+    from models.bs_roformer.attend_sage import Attend as AttendSage
+except:
+    pass
+from torch.utils.checkpoint import checkpoint
+
+from beartype.typing import Tuple, Optional, List, Callable
+from beartype import beartype
+
+from rotary_embedding_torch import RotaryEmbedding
+
+from einops import rearrange, pack, unpack
+from einops.layers.torch import Rearrange
+# helper functions
+
+def exists(val):
+    return val is not None
+
+
+def default(v, d):
+    return v if exists(v) else d
+
+
+def pack_one(t, pattern):
+    return pack([t], pattern)
+
+
+def unpack_one(t, ps, pattern):
+    return unpack(t, ps, pattern)[0]
+
+
+# norm
+
+def l2norm(t):
+    return F.normalize(t, dim = -1, p = 2)
+
+
+class RMSNorm(Module):
+    def __init__(self, dim):
+        super().__init__()
+        self.scale = dim ** 0.5
+        self.gamma = nn.Parameter(torch.ones(dim))
+
+    def forward(self, x):
+        return F.normalize(x, dim=-1) * self.scale * self.gamma
+
+
+# attention
+
+class FeedForward(Module):
+    def __init__(
+            self,
+            dim,
+            mult=4,
+            dropout=0.
+    ):
+        super().__init__()
+        dim_inner = int(dim * mult)
+        self.net = nn.Sequential(
+            RMSNorm(dim),
+            nn.Linear(dim, dim_inner),
+            nn.GELU(),
+            nn.Dropout(dropout),
+            nn.Linear(dim_inner, dim),
+            nn.Dropout(dropout)
+        )
+
+    def forward(self, x):
+        return self.net(x)
+
+class Attention(Module):
+    def __init__(
+            self,
+            dim,
+            heads=8,
+            dim_head=64,
+            dropout=0.,
+            rotary_embed=None,
+            flash=True,
+            sage_attention=False,
+    ):
+        super().__init__()
+        self.heads = heads
+        self.scale = dim_head ** -0.5
+        dim_inner = heads * dim_head
+
+        self.rotary_embed = rotary_embed
+
+        if sage_attention:
+            self.attend = AttendSage(flash=flash, dropout=dropout)
+        else:
+            self.attend = Attend(flash=flash, dropout=dropout)
+
+        self.norm = RMSNorm(dim)
+        self.to_qkv = nn.Linear(dim, dim_inner * 3, bias=False)
+
+        self.to_gates = nn.Linear(dim, heads)
+
+        self.to_out = nn.Sequential(
+            nn.Linear(dim_inner, dim, bias=False),
+            nn.Dropout(dropout)
+        )
+
+    def forward(self, x):
+        x = self.norm(x)
+
+        q, k, v = rearrange(self.to_qkv(x), 'b n (qkv h d) -> qkv b h n d', qkv=3, h=self.heads)
+
+        if exists(self.rotary_embed):
+            q = self.rotary_embed.rotate_queries_or_keys(q)
+            k = self.rotary_embed.rotate_queries_or_keys(k)
+
+        out = self.attend(q, k, v)
+
+        gates = self.to_gates(x)
+        out = out * rearrange(gates, 'b n h -> b h n 1').sigmoid()
+
+        out = rearrange(out, 'b h n d -> b n (h d)')
+        return self.to_out(out)
+
+
+class LinearAttention(Module):
+    """
+    this flavor of linear attention proposed in https://arxiv.org/abs/2106.09681 by El-Nouby et al.
+    """
+
+    @beartype
+    def __init__(
+            self,
+            *,
+            dim,
+            dim_head=32,
+            heads=8,
+            scale=8,
+            flash=False,
+            dropout=0.,
+            sage_attention=False,
+    ):
+        super().__init__()
+        dim_inner = dim_head * heads
+        self.norm = RMSNorm(dim)
+
+        self.to_qkv = nn.Sequential(
+            nn.Linear(dim, dim_inner * 3, bias=False),
+            Rearrange('b n (qkv h d) -> qkv b h d n', qkv=3, h=heads)
+        )
+
+        self.temperature = nn.Parameter(torch.ones(heads, 1, 1))
+
+        if sage_attention:
+            self.attend = AttendSage(
+                scale=scale,
+                dropout=dropout,
+                flash=flash
+            )
+        else:
+            self.attend = Attend(
+                scale=scale,
+                dropout=dropout,
+                flash=flash
+            )
+
+        self.to_out = nn.Sequential(
+            Rearrange('b h d n -> b n (h d)'),
+            nn.Linear(dim_inner, dim, bias=False)
+        )
+
+    def forward(
+            self,
+            x
+    ):
+        x = self.norm(x)
+
+        q, k, v = self.to_qkv(x)
+
+        q, k = map(l2norm, (q, k))
+        q = q * self.temperature.exp()
+
+        out = self.attend(q, k, v)
+
+        return self.to_out(out)
+
+class Transformer(Module):
+    def __init__(
+            self,
+            *,
+            dim,
+            depth,
+            dim_head=64,
+            heads=8,
+            attn_dropout=0.,
+            ff_dropout=0.,
+            ff_mult=4,
+            norm_output=True,
+            rotary_embed=None,
+            flash_attn=True,
+            linear_attn=False,
+            sage_attention=False,
+    ):
+        super().__init__()
+        self.layers = ModuleList([])
+
+        for _ in range(depth):
+            if linear_attn:
+                attn = LinearAttention(
+                    dim=dim,
+                    dim_head=dim_head,
+                    heads=heads,
+                    dropout=attn_dropout,
+                    flash=flash_attn,
+                    sage_attention=sage_attention
+                )
+            else:
+                attn = Attention(
+                    dim=dim,
+                    dim_head=dim_head,
+                    heads=heads,
+                    dropout=attn_dropout,
+                    rotary_embed=rotary_embed,
+                    flash=flash_attn,
+                    sage_attention=sage_attention
+                )
+
+            self.layers.append(ModuleList([
+                attn,
+                FeedForward(dim=dim, mult=ff_mult, dropout=ff_dropout)
+            ]))
+
+        self.norm = RMSNorm(dim) if norm_output else nn.Identity()
+
+    def forward(self, x):
+
+        for attn, ff in self.layers:
+            x = attn(x) + x
+            x = ff(x) + x
+
+        return self.norm(x)
+
+
+# bandsplit module
+
+
+
+class BandSplit(Module):
+    @beartype
+    def __init__(
+            self,
+            dim,
+            dim_inputs: Tuple[int, ...]
+    ):
+        super().__init__()
+        self.dim_inputs = dim_inputs
+        self.to_features = ModuleList([])
+
+        for dim_in in dim_inputs:
+            net = nn.Sequential(
+                RMSNorm(dim_in),
+                nn.Linear(dim_in, dim)
+            )
+
+            self.to_features.append(net)
+        
+    def forward(self, x):
+        
+        x = x.split(self.dim_inputs, dim=-1)
+
+        outs = []
+        for split_input, to_feature in zip(x, self.to_features):
+            split_output = to_feature(split_input)
+            outs.append(split_output)
+        
+        x = torch.stack(outs, dim=-2)
+
+        return x
+
+def MLP(
+        dim_in,
+        dim_out,
+        dim_hidden=None,
+        depth=1,
+        activation=nn.Tanh
+):
+    dim_hidden = default(dim_hidden, dim_in)
+
+    net = []
+    dims = (dim_in, *((dim_hidden,) * (depth - 1)), dim_out)
+
+    for ind, (layer_dim_in, layer_dim_out) in enumerate(zip(dims[:-1], dims[1:])):
+        is_last = ind == (len(dims) - 2)
+
+        net.append(nn.Linear(layer_dim_in, layer_dim_out))
+
+        if is_last:
+            continue
+
+        net.append(activation())
+
+    return nn.Sequential(*net)
+
+class MaskEstimator(Module):
+    @beartype
+    def __init__(
+            self,
+            dim,
+            dim_inputs: Tuple[int, ...],
+            depth,
+            mlp_expansion_factor=4
+    ):
+        super().__init__()
+        self.dim_inputs = dim_inputs
+        self.to_freqs = ModuleList([])
+        dim_hidden = dim * mlp_expansion_factor
+
+        for dim_in in dim_inputs:
+            net = []
+
+            mlp = nn.Sequential(
+                MLP(dim, dim_in * 2, dim_hidden=dim_hidden, depth=depth),
+                nn.GLU(dim=-1)
+            )
+
+            self.to_freqs.append(mlp)
+        
+        self.layers = ModuleList([])
+        
+        heads = 8
+        dim_head = 64
+        
+        transformer_kwargs = dict(
+            dim=dim,
+            heads=heads,
+            dim_head=dim_head,
+            attn_dropout=0.,
+            ff_dropout=0.,
+            flash_attn=True,
+            norm_output=False,
+            sage_attention=False,
+        )
+
+        time_rotary_embed = RotaryEmbedding(dim=dim_head)
+        freq_rotary_embed = RotaryEmbedding(dim=dim_head)
+
+        for _ in range(4):
+            tran_modules = []
+            tran_modules.append(
+                Transformer(depth=1, rotary_embed=time_rotary_embed, **transformer_kwargs)
+            )
+            tran_modules.append(
+                Transformer(depth=1, rotary_embed=freq_rotary_embed, **transformer_kwargs)
+            )
+            self.layers.append(nn.ModuleList(tran_modules))
+        
+        self.norm = RMSNorm(dim)
+
+    def forward(self, x):
+
+        for i, transformer_block in enumerate(self.layers):
+
+
+            time_transformer, freq_transformer = transformer_block
+
+
+            x = rearrange(x, 'b t f d -> b f t d')
+            x, ps = pack([x], '* t d')
+
+
+            x = time_transformer(x)
+
+            x, = unpack(x, ps, '* t d')
+            x = rearrange(x, 'b f t d -> b t f d')
+            x, ps = pack([x], '* f d')
+
+
+            x = freq_transformer(x)
+
+            x, = unpack(x, ps, '* f d')
+        
+        x = self.norm(x)
+        
+        x = x.unbind(dim=-2)
+
+        outs = []
+
+        for band_features, mlp in zip(x, self.to_freqs):
+            freq_out = mlp(band_features)
+            outs.append(freq_out)
+
+        return torch.cat(outs, dim=-1)
+
+
+# main class
+
+DEFAULT_FREQS_PER_BANDS = (
+    2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+    2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+    2, 2, 2, 2,
+    4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+    12, 12, 12, 12, 12, 12, 12, 12,
+    24, 24, 24, 24, 24, 24, 24, 24,
+    48, 48, 48, 48, 48, 48, 48, 48,
+    128, 129,
+)
+
+class BSRoformer(Module):
+
+    @beartype
+    def __init__(
+            self,
+            dim,
+            *,
+            depth,
+            stereo=False,
+            num_stems=1,
+            time_transformer_depth=2,
+            freq_transformer_depth=2,
+            linear_transformer_depth=0,
+            freqs_per_bands: Tuple[int, ...] = DEFAULT_FREQS_PER_BANDS,
+            # in the paper, they divide into ~60 bands, test with 1 for starters
+            dim_head=64,
+            heads=8,
+            attn_dropout=0.,
+            ff_dropout=0.,
+            flash_attn=True,
+            dim_freqs_in=1025,
+            stft_n_fft=2048,
+            stft_hop_length=512,
+            # 10ms at 44100Hz, from sections 4.1, 4.4 in the paper - @faroit recommends // 2 or // 4 for better reconstruction
+            stft_win_length=2048,
+            stft_normalized=False,
+            stft_window_fn: Optional[Callable] = None,
+            mask_estimator_depth=2,
+            multi_stft_resolution_loss_weight=1.,
+            multi_stft_resolutions_window_sizes: Tuple[int, ...] = (4096, 2048, 1024, 512, 256),
+            multi_stft_hop_size=147,
+            multi_stft_normalized=False,
+            multi_stft_window_fn: Callable = torch.hann_window,
+            mlp_expansion_factor=4,
+            use_torch_checkpoint=False,
+            skip_connection=False,
+            sage_attention=False,
+    ):
+        super().__init__()
+
+        self.stereo = stereo
+        self.audio_channels = 2 if stereo else 1
+        self.num_stems = num_stems
+        self.use_torch_checkpoint = use_torch_checkpoint
+        self.skip_connection = skip_connection
+
+        self.layers = ModuleList([])
+
+        if sage_attention:
+            print("Use Sage Attention")
+
+        transformer_kwargs = dict(
+            dim=dim,
+            heads=heads,
+            dim_head=dim_head,
+            attn_dropout=attn_dropout,
+            ff_dropout=ff_dropout,
+            flash_attn=flash_attn,
+            norm_output=False,
+            sage_attention=sage_attention,
+        )
+
+        time_rotary_embed = RotaryEmbedding(dim=dim_head)
+        freq_rotary_embed = RotaryEmbedding(dim=dim_head)
+
+        for _ in range(depth):
+            tran_modules = []
+            tran_modules.append(
+                Transformer(depth=time_transformer_depth, rotary_embed=time_rotary_embed, **transformer_kwargs)
+            )
+            tran_modules.append(
+                Transformer(depth=freq_transformer_depth, rotary_embed=freq_rotary_embed, **transformer_kwargs)
+            )
+            self.layers.append(nn.ModuleList(tran_modules))
+
+        self.final_norm = RMSNorm(dim)
+
+        self.stft_kwargs = dict(
+            n_fft=stft_n_fft,
+            hop_length=stft_hop_length,
+            win_length=stft_win_length,
+            normalized=stft_normalized
+        )
+
+        self.stft_window_fn = partial(default(stft_window_fn, torch.hann_window), stft_win_length)
+
+        freqs = torch.stft(torch.randn(1, 4096), **self.stft_kwargs, window=torch.ones(stft_win_length), return_complex=True).shape[1]
+
+        assert len(freqs_per_bands) > 1
+        assert sum(
+            freqs_per_bands) == freqs, f'the number of freqs in the bands must equal {freqs} based on the STFT settings, but got {sum(freqs_per_bands)}'
+
+        freqs_per_bands_with_complex = tuple(2 * f * self.audio_channels for f in freqs_per_bands)
+
+        self.band_split = BandSplit(
+            dim=dim,
+            dim_inputs=freqs_per_bands_with_complex
+        )
+
+        self.mask_estimators = nn.ModuleList([])
+
+        for _ in range(num_stems):
+            mask_estimator = MaskEstimator(
+                dim=dim,
+                dim_inputs=freqs_per_bands_with_complex,
+                depth=mask_estimator_depth,
+                mlp_expansion_factor=mlp_expansion_factor,
+            )
+
+            self.mask_estimators.append(mask_estimator)
+
+        # for the multi-resolution stft loss
+
+        self.multi_stft_resolution_loss_weight = multi_stft_resolution_loss_weight
+        self.multi_stft_resolutions_window_sizes = multi_stft_resolutions_window_sizes
+        self.multi_stft_n_fft = stft_n_fft
+        self.multi_stft_window_fn = multi_stft_window_fn
+
+        self.multi_stft_kwargs = dict(
+            hop_length=multi_stft_hop_size,
+            normalized=multi_stft_normalized
+        )
+
+    def forward(
+            self,
+            raw_audio,
+            target=None,
+            return_loss_breakdown=False
+    ):
+        """
+        einops
+
+        b - batch
+        f - freq
+        t - time
+        s - audio channel (1 for mono, 2 for stereo)
+        n - number of 'stems'
+        c - complex (2)
+        d - feature dimension
+        """
+
+        device = raw_audio.device
+
+        # defining whether model is loaded on MPS (MacOS GPU accelerator)
+        x_is_mps = True if device.type == "mps" else False
+
+        if raw_audio.ndim == 2:
+            raw_audio = rearrange(raw_audio, 'b t -> b 1 t')
+
+        channels = raw_audio.shape[1]
+        assert (not self.stereo and channels == 1) or (self.stereo and channels == 2), 'stereo needs to be set to True if passing in audio signal that is stereo (channel dimension of 2). also need to be False if mono (channel dimension of 1)'
+
+        # to stft
+
+        raw_audio, batch_audio_channel_packed_shape = pack_one(raw_audio, '* t')
+
+        stft_window = self.stft_window_fn(device=device)
+
+        # RuntimeError: FFT operations are only supported on MacOS 14+
+        # Since it's tedious to define whether we're on correct MacOS version - simple try-catch is used
+        try:
+            stft_repr = torch.stft(raw_audio, **self.stft_kwargs, window=stft_window, return_complex=True)
+        except:
+            stft_repr = torch.stft(raw_audio.cpu() if x_is_mps else raw_audio, **self.stft_kwargs,
+                                   window=stft_window.cpu() if x_is_mps else stft_window, return_complex=True).to(
+                device)
+        stft_repr = torch.view_as_real(stft_repr)
+
+        stft_repr = unpack_one(stft_repr, batch_audio_channel_packed_shape, '* f t c')
+
+        # merge stereo / mono into the frequency, with frequency leading dimension, for band splitting
+        stft_repr = rearrange(stft_repr,'b s f t c -> b (f s) t c')
+
+        x = rearrange(stft_repr, 'b f t c -> b t (f c)')
+
+
+        x = self.band_split(x)
+        
+        # axial / hierarchical attention
+        
+        for i, transformer_block in enumerate(self.layers):
+
+
+            time_transformer, freq_transformer = transformer_block
+
+
+            x = rearrange(x, 'b t f d -> b f t d')
+            x, ps = pack([x], '* t d')
+
+
+            x = time_transformer(x)
+
+            x, = unpack(x, ps, '* t d')
+            x = rearrange(x, 'b f t d -> b t f d')
+            x, ps = pack([x], '* f d')
+
+
+            x = freq_transformer(x)
+
+            x, = unpack(x, ps, '* f d')
+
+
+        x = self.final_norm(x)
+
+        num_stems = len(self.mask_estimators)
+
+
+        mask = torch.stack([fn(x) for fn in self.mask_estimators], dim=1)
+        mask = rearrange(mask, 'b n t (f c) -> b n f t c', c=2)
+
+        # modulate frequency representation
+
+        stft_repr = rearrange(stft_repr, 'b f t c -> b 1 f t c')
+
+        stft_repr = torch.view_as_complex(stft_repr)
+        mask = torch.view_as_complex(mask)
+
+        stft_repr = stft_repr * mask
+
+        # istft
+
+        stft_repr = rearrange(stft_repr, 'b n (f s) t -> (b n s) f t', s=self.audio_channels)
+
+        try:
+            recon_audio = torch.istft(stft_repr, **self.stft_kwargs, window=stft_window, return_complex=False, length=raw_audio.shape[-1])
+        except:
+            recon_audio = torch.istft(stft_repr.cpu() if x_is_mps else stft_repr, **self.stft_kwargs, window=stft_window.cpu() if x_is_mps else stft_window, return_complex=False, length=raw_audio.shape[-1]).to(device)
+
+        recon_audio = rearrange(recon_audio, '(b n s) t -> b n s t', s=self.audio_channels, n=num_stems)
+
+        if num_stems == 1:
+            recon_audio = rearrange(recon_audio, 'b 1 s t -> b s t')
+
+        # if a target is passed in, calculate loss for learning
+
+        if not exists(target):
+            return recon_audio
+
+        if self.num_stems > 1:
+            assert target.ndim == 4 and target.shape[1] == self.num_stems
+
+        if target.ndim == 2:
+            target = rearrange(target, '... t -> ... 1 t')
+
+        target = target[..., :recon_audio.shape[-1]]  # protect against lost length on istft
+
+        loss = F.l1_loss(recon_audio, target)
+
+        multi_stft_resolution_loss = 0.
+
+        for window_size in self.multi_stft_resolutions_window_sizes:
+            res_stft_kwargs = dict(
+                n_fft=max(window_size, self.multi_stft_n_fft),  # not sure what n_fft is across multi resolution stft
+                win_length=window_size,
+                return_complex=True,
+                window=self.multi_stft_window_fn(window_size, device=device),
+                **self.multi_stft_kwargs,
+            )
+
+            recon_Y = torch.stft(rearrange(recon_audio, '... s t -> (... s) t'), **res_stft_kwargs)
+            target_Y = torch.stft(rearrange(target, '... s t -> (... s) t'), **res_stft_kwargs)
+
+            multi_stft_resolution_loss = multi_stft_resolution_loss + F.l1_loss(recon_Y, target_Y)
+
+        weighted_multi_resolution_loss = multi_stft_resolution_loss * self.multi_stft_resolution_loss_weight
+
+        total_loss = loss + weighted_multi_resolution_loss
+
+        if not return_loss_breakdown:
+            return total_loss
+
+        return total_loss, (loss, multi_stft_resolution_loss)