add unet grad tts

src/diffusers/__init__.py

@@ -8,6 +8,7 @@ from .modeling_utils import ModelMixin
 from .models.unet import UNetModel
 from .models.unet_glide import GLIDEUNetModel, GLIDESuperResUNetModel, GLIDETextToImageUNetModel
 from .models.unet_ldm import UNetLDMModel
+from .models.unet_grad_tts import UNetGradTTSModel
 from .pipeline_utils import DiffusionPipeline
 from .pipelines import DDIM, DDPM, GLIDE, LatentDiffusion, PNDM, BDDM
 from .schedulers import DDIMScheduler, DDPMScheduler, SchedulerMixin, PNDMScheduler

src/diffusers/models/__init__.py

@@ -19,3 +19,4 @@
 from .unet import UNetModel
 from .unet_glide import GLIDEUNetModel, GLIDESuperResUNetModel, GLIDETextToImageUNetModel
 from .unet_ldm import UNetLDMModel
+from .unet_grad_tts import UNetGradTTSModel

src/diffusers/models/unet_grad_tts.py

@@ -0,0 +1,233 @@
+import math
+
+import torch
+
+try:
+    from einops import rearrange, repeat
+except:
+    print("Einops is not installed")
+    pass
+
+from ..configuration_utils import ConfigMixin
+from ..modeling_utils import ModelMixin
+
+class Mish(torch.nn.Module):
+    def forward(self, x):
+        return x * torch.tanh(torch.nn.functional.softplus(x))
+
+
+class Upsample(torch.nn.Module):
+    def __init__(self, dim):
+        super(Upsample, self).__init__()
+        self.conv = torch.nn.ConvTranspose2d(dim, dim, 4, 2, 1)
+
+    def forward(self, x):
+        return self.conv(x)
+
+
+class Downsample(torch.nn.Module):
+    def __init__(self, dim):
+        super(Downsample, self).__init__()
+        self.conv = torch.nn.Conv2d(dim, dim, 3, 2, 1)
+
+    def forward(self, x):
+        return self.conv(x)
+
+
+class Rezero(torch.nn.Module):
+    def __init__(self, fn):
+        super(Rezero, self).__init__()
+        self.fn = fn
+        self.g = torch.nn.Parameter(torch.zeros(1))
+
+    def forward(self, x):
+        return self.fn(x) * self.g
+
+
+class Block(torch.nn.Module):
+    def __init__(self, dim, dim_out, groups=8):
+        super(Block, self).__init__()
+        self.block = torch.nn.Sequential(torch.nn.Conv2d(dim, dim_out, 3, 
+                                         padding=1), torch.nn.GroupNorm(
+                                         groups, dim_out), Mish())
+
+    def forward(self, x, mask):
+        output = self.block(x * mask)
+        return output * mask
+
+
+class ResnetBlock(torch.nn.Module):
+    def __init__(self, dim, dim_out, time_emb_dim, groups=8):
+        super(ResnetBlock, self).__init__()
+        self.mlp = torch.nn.Sequential(Mish(), torch.nn.Linear(time_emb_dim, 
+                                                               dim_out))
+
+        self.block1 = Block(dim, dim_out, groups=groups)
+        self.block2 = Block(dim_out, dim_out, groups=groups)
+        if dim != dim_out:
+            self.res_conv = torch.nn.Conv2d(dim, dim_out, 1)
+        else:
+            self.res_conv = torch.nn.Identity()
+
+    def forward(self, x, mask, time_emb):
+        h = self.block1(x, mask)
+        h += self.mlp(time_emb).unsqueeze(-1).unsqueeze(-1)
+        h = self.block2(h, mask)
+        output = h + self.res_conv(x * mask)
+        return output
+
+
+class LinearAttention(torch.nn.Module):
+    def __init__(self, dim, heads=4, dim_head=32):
+        super(LinearAttention, self).__init__()
+        self.heads = heads
+        hidden_dim = dim_head * heads
+        self.to_qkv = torch.nn.Conv2d(dim, hidden_dim * 3, 1, bias=False)
+        self.to_out = torch.nn.Conv2d(hidden_dim, dim, 1)            
+
+    def forward(self, x):
+        b, c, h, w = x.shape
+        qkv = self.to_qkv(x)
+        q, k, v = rearrange(qkv, 'b (qkv heads c) h w -> qkv b heads c (h w)', 
+                            heads = self.heads, qkv=3)            
+        k = k.softmax(dim=-1)
+        context = torch.einsum('bhdn,bhen->bhde', k, v)
+        out = torch.einsum('bhde,bhdn->bhen', context, q)
+        out = rearrange(out, 'b heads c (h w) -> b (heads c) h w', 
+                        heads=self.heads, h=h, w=w)
+        return self.to_out(out)
+
+
+class Residual(torch.nn.Module):
+    def __init__(self, fn):
+        super(Residual, self).__init__()
+        self.fn = fn
+
+    def forward(self, x, *args, **kwargs):
+        output = self.fn(x, *args, **kwargs) + x
+        return output
+
+
+class SinusoidalPosEmb(torch.nn.Module):
+    def __init__(self, dim):
+        super(SinusoidalPosEmb, self).__init__()
+        self.dim = dim
+
+    def forward(self, x, scale=1000):
+        device = x.device
+        half_dim = self.dim // 2
+        emb = math.log(10000) / (half_dim - 1)
+        emb = torch.exp(torch.arange(half_dim, device=device).float() * -emb)
+        emb = scale * x.unsqueeze(1) * emb.unsqueeze(0)
+        emb = torch.cat((emb.sin(), emb.cos()), dim=-1)
+        return emb
+
+
+class UNetGradTTSModel(ModelMixin, ConfigMixin):
+    def __init__(
+        self,
+        dim,
+        dim_mults=(1, 2, 4),
+        groups=8,
+        n_spks=None,
+        spk_emb_dim=64,
+        n_feats=80,
+        pe_scale=1000
+    ):
+        super(UNetGradTTSModel, self).__init__()
+
+        self.register(
+            dim=dim,
+            dim_mults=dim_mults,
+            groups=groups,
+            n_spks=n_spks,
+            spk_emb_dim=spk_emb_dim,
+            n_feats=n_feats,
+            pe_scale=pe_scale
+        )
+        
+        self.dim = dim
+        self.dim_mults = dim_mults
+        self.groups = groups
+        self.n_spks = n_spks if not isinstance(n_spks, type(None)) else 1
+        self.spk_emb_dim = spk_emb_dim
+        self.pe_scale = pe_scale
+        
+        if n_spks > 1:
+            self.spk_mlp = torch.nn.Sequential(torch.nn.Linear(spk_emb_dim, spk_emb_dim * 4), Mish(),
+                                               torch.nn.Linear(spk_emb_dim * 4, n_feats))
+        self.time_pos_emb = SinusoidalPosEmb(dim)
+        self.mlp = torch.nn.Sequential(torch.nn.Linear(dim, dim * 4), Mish(),
+                                       torch.nn.Linear(dim * 4, dim))
+
+        dims = [2 + (1 if n_spks > 1 else 0), *map(lambda m: dim * m, dim_mults)]
+        in_out = list(zip(dims[:-1], dims[1:]))
+        self.downs = torch.nn.ModuleList([])
+        self.ups = torch.nn.ModuleList([])
+        num_resolutions = len(in_out)
+
+        for ind, (dim_in, dim_out) in enumerate(in_out):
+            is_last = ind >= (num_resolutions - 1)
+            self.downs.append(torch.nn.ModuleList([
+                       ResnetBlock(dim_in, dim_out, time_emb_dim=dim),
+                       ResnetBlock(dim_out, dim_out, time_emb_dim=dim),
+                       Residual(Rezero(LinearAttention(dim_out))),
+                       Downsample(dim_out) if not is_last else torch.nn.Identity()]))
+
+        mid_dim = dims[-1]
+        self.mid_block1 = ResnetBlock(mid_dim, mid_dim, time_emb_dim=dim)
+        self.mid_attn = Residual(Rezero(LinearAttention(mid_dim)))
+        self.mid_block2 = ResnetBlock(mid_dim, mid_dim, time_emb_dim=dim)
+
+        for ind, (dim_in, dim_out) in enumerate(reversed(in_out[1:])):
+            self.ups.append(torch.nn.ModuleList([
+                     ResnetBlock(dim_out * 2, dim_in, time_emb_dim=dim),
+                     ResnetBlock(dim_in, dim_in, time_emb_dim=dim),
+                     Residual(Rezero(LinearAttention(dim_in))),
+                     Upsample(dim_in)]))
+        self.final_block = Block(dim, dim)
+        self.final_conv = torch.nn.Conv2d(dim, 1, 1)
+
+    def forward(self, x, mask, mu, t, spk=None):
+        if not isinstance(spk, type(None)):
+            s = self.spk_mlp(spk)
+        
+        t = self.time_pos_emb(t, scale=self.pe_scale)
+        t = self.mlp(t)
+
+        if self.n_spks < 2:
+            x = torch.stack([mu, x], 1)
+        else:
+            s = s.unsqueeze(-1).repeat(1, 1, x.shape[-1])
+            x = torch.stack([mu, x, s], 1)
+        mask = mask.unsqueeze(1)
+
+        hiddens = []
+        masks = [mask]
+        for resnet1, resnet2, attn, downsample in self.downs:
+            mask_down = masks[-1]
+            x = resnet1(x, mask_down, t)
+            x = resnet2(x, mask_down, t)
+            x = attn(x)
+            hiddens.append(x)
+            x = downsample(x * mask_down)
+            masks.append(mask_down[:, :, :, ::2])
+
+        masks = masks[:-1]
+        mask_mid = masks[-1]
+        x = self.mid_block1(x, mask_mid, t)
+        x = self.mid_attn(x)
+        x = self.mid_block2(x, mask_mid, t)
+
+        for resnet1, resnet2, attn, upsample in self.ups:
+            mask_up = masks.pop()
+            x = torch.cat((x, hiddens.pop()), dim=1)
+            x = resnet1(x, mask_up, t)
+            x = resnet2(x, mask_up, t)
+            x = attn(x)
+            x = upsample(x * mask_up)
+
+        x = self.final_block(x, mask)
+        output = self.final_conv(x * mask)
+
+        return (output * mask).squeeze(1)