[Core] move transformer scripts to `transformers` modules (#6747)

* move transformer scripts to transformers modules

* move transformer model test

* move prior transformer test to  directory

* fix doc path

* correct doc path

* add: __init__.py

docs/source/en/api/models/prior_transformer.md

@@ -24,4 +24,4 @@ The abstract from the paper is:
 
 ## PriorTransformerOutput
 
-[[autodoc]] models.prior_transformer.PriorTransformerOutput
+[[autodoc]] models.transformers.prior_transformer.PriorTransformerOutput

docs/source/en/api/models/transformer2d.md

@@ -38,4 +38,4 @@ It is assumed one of the input classes is the masked latent pixel. The predicted
 
 ## Transformer2DModelOutput
 
-[[autodoc]] models.transformer_2d.Transformer2DModelOutput
+[[autodoc]] models.transformers.transformer_2d.Transformer2DModelOutput

docs/source/en/api/models/transformer_temporal.md

@@ -16,8 +16,8 @@ A Transformer model for video-like data.
 
 ## TransformerTemporalModel
 
-[[autodoc]] models.transformer_temporal.TransformerTemporalModel
+[[autodoc]] models.transformers.transformer_temporal.TransformerTemporalModel
 
 ## TransformerTemporalModelOutput
 
-[[autodoc]] models.transformer_temporal.TransformerTemporalModelOutput
+[[autodoc]] models.transformers.transformer_temporal.TransformerTemporalModelOutput

scripts/convert_kakao_brain_unclip_to_diffusers.py

@@ -6,7 +6,7 @@ from accelerate import load_checkpoint_and_dispatch
 from transformers import CLIPTextModelWithProjection, CLIPTokenizer
 
 from diffusers import UnCLIPPipeline, UNet2DConditionModel, UNet2DModel
-from diffusers.models.prior_transformer import PriorTransformer
+from diffusers.models.transformers.prior_transformer import PriorTransformer
 from diffusers.pipelines.unclip.text_proj import UnCLIPTextProjModel
 from diffusers.schedulers.scheduling_unclip import UnCLIPScheduler
 

scripts/convert_kandinsky_to_diffusers.py

@@ -6,7 +6,7 @@ import torch
 from accelerate import load_checkpoint_and_dispatch
 
 from diffusers import UNet2DConditionModel
-from diffusers.models.prior_transformer import PriorTransformer
+from diffusers.models.transformers.prior_transformer import PriorTransformer
 from diffusers.models.vq_model import VQModel
 
 

scripts/convert_shap_e_to_diffusers.py

@@ -4,7 +4,7 @@ import tempfile
 import torch
 from accelerate import load_checkpoint_and_dispatch
 
-from diffusers.models.prior_transformer import PriorTransformer
+from diffusers.models.transformers.prior_transformer import PriorTransformer
 from diffusers.pipelines.shap_e import ShapERenderer
 
 

src/diffusers/models/__init__.py

@@ -35,10 +35,10 @@ if is_torch_available():
     _import_structure["dual_transformer_2d"] = ["DualTransformer2DModel"]
     _import_structure["embeddings"] = ["ImageProjection"]
     _import_structure["modeling_utils"] = ["ModelMixin"]
-    _import_structure["prior_transformer"] = ["PriorTransformer"]
-    _import_structure["t5_film_transformer"] = ["T5FilmDecoder"]
-    _import_structure["transformer_2d"] = ["Transformer2DModel"]
-    _import_structure["transformer_temporal"] = ["TransformerTemporalModel"]
+    _import_structure["transformers.prior_transformer"] = ["PriorTransformer"]
+    _import_structure["transformers.t5_film_transformer"] = ["T5FilmDecoder"]
+    _import_structure["transformers.transformer_2d"] = ["Transformer2DModel"]
+    _import_structure["transformers.transformer_temporal"] = ["TransformerTemporalModel"]
     _import_structure["unets.unet_1d"] = ["UNet1DModel"]
     _import_structure["unets.unet_2d"] = ["UNet2DModel"]
     _import_structure["unets.unet_2d_condition"] = ["UNet2DConditionModel"]
@@ -66,13 +66,15 @@ if TYPE_CHECKING or DIFFUSERS_SLOW_IMPORT:
             ConsistencyDecoderVAE,
         )
         from .controlnet import ControlNetModel
-        from .dual_transformer_2d import DualTransformer2DModel
         from .embeddings import ImageProjection
         from .modeling_utils import ModelMixin
-        from .prior_transformer import PriorTransformer
-        from .t5_film_transformer import T5FilmDecoder
-        from .transformer_2d import Transformer2DModel
-        from .transformer_temporal import TransformerTemporalModel
+        from .transformers import (
+            DualTransformer2DModel,
+            PriorTransformer,
+            T5FilmDecoder,
+            Transformer2DModel,
+            TransformerTemporalModel,
+        )
         from .unets import (
             Kandinsky3UNet,
             MotionAdapter,

src/diffusers/models/dual_transformer_2d.py

@@ -11,145 +11,10 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-from typing import Optional
+from ..utils import deprecate
+from .transformers.dual_transformer_2d import DualTransformer2DModel
 
-from torch import nn
 
-from .transformer_2d import Transformer2DModel, Transformer2DModelOutput
-
-
-class DualTransformer2DModel(nn.Module):
-    """
-    Dual transformer wrapper that combines two `Transformer2DModel`s for mixed inference.
-
-    Parameters:
-        num_attention_heads (`int`, *optional*, defaults to 16): The number of heads to use for multi-head attention.
-        attention_head_dim (`int`, *optional*, defaults to 88): The number of channels in each head.
-        in_channels (`int`, *optional*):
-            Pass if the input is continuous. The number of channels in the input and output.
-        num_layers (`int`, *optional*, defaults to 1): The number of layers of Transformer blocks to use.
-        dropout (`float`, *optional*, defaults to 0.1): The dropout probability to use.
-        cross_attention_dim (`int`, *optional*): The number of encoder_hidden_states dimensions to use.
-        sample_size (`int`, *optional*): Pass if the input is discrete. The width of the latent images.
-            Note that this is fixed at training time as it is used for learning a number of position embeddings. See
-            `ImagePositionalEmbeddings`.
-        num_vector_embeds (`int`, *optional*):
-            Pass if the input is discrete. The number of classes of the vector embeddings of the latent pixels.
-            Includes the class for the masked latent pixel.
-        activation_fn (`str`, *optional*, defaults to `"geglu"`): Activation function to be used in feed-forward.
-        num_embeds_ada_norm ( `int`, *optional*): Pass if at least one of the norm_layers is `AdaLayerNorm`.
-            The number of diffusion steps used during training. Note that this is fixed at training time as it is used
-            to learn a number of embeddings that are added to the hidden states. During inference, you can denoise for
-            up to but not more than steps than `num_embeds_ada_norm`.
-        attention_bias (`bool`, *optional*):
-            Configure if the TransformerBlocks' attention should contain a bias parameter.
-    """
-
-    def __init__(
-        self,
-        num_attention_heads: int = 16,
-        attention_head_dim: int = 88,
-        in_channels: Optional[int] = None,
-        num_layers: int = 1,
-        dropout: float = 0.0,
-        norm_num_groups: int = 32,
-        cross_attention_dim: Optional[int] = None,
-        attention_bias: bool = False,
-        sample_size: Optional[int] = None,
-        num_vector_embeds: Optional[int] = None,
-        activation_fn: str = "geglu",
-        num_embeds_ada_norm: Optional[int] = None,
-    ):
-        super().__init__()
-        self.transformers = nn.ModuleList(
-            [
-                Transformer2DModel(
-                    num_attention_heads=num_attention_heads,
-                    attention_head_dim=attention_head_dim,
-                    in_channels=in_channels,
-                    num_layers=num_layers,
-                    dropout=dropout,
-                    norm_num_groups=norm_num_groups,
-                    cross_attention_dim=cross_attention_dim,
-                    attention_bias=attention_bias,
-                    sample_size=sample_size,
-                    num_vector_embeds=num_vector_embeds,
-                    activation_fn=activation_fn,
-                    num_embeds_ada_norm=num_embeds_ada_norm,
-                )
-                for _ in range(2)
-            ]
-        )
-
-        # Variables that can be set by a pipeline:
-
-        # The ratio of transformer1 to transformer2's output states to be combined during inference
-        self.mix_ratio = 0.5
-
-        # The shape of `encoder_hidden_states` is expected to be
-        # `(batch_size, condition_lengths[0]+condition_lengths[1], num_features)`
-        self.condition_lengths = [77, 257]
-
-        # Which transformer to use to encode which condition.
-        # E.g. `(1, 0)` means that we'll use `transformers[1](conditions[0])` and `transformers[0](conditions[1])`
-        self.transformer_index_for_condition = [1, 0]
-
-    def forward(
-        self,
-        hidden_states,
-        encoder_hidden_states,
-        timestep=None,
-        attention_mask=None,
-        cross_attention_kwargs=None,
-        return_dict: bool = True,
-    ):
-        """
-        Args:
-            hidden_states ( When discrete, `torch.LongTensor` of shape `(batch size, num latent pixels)`.
-                When continuous, `torch.FloatTensor` of shape `(batch size, channel, height, width)`): Input
-                hidden_states.
-            encoder_hidden_states ( `torch.LongTensor` of shape `(batch size, encoder_hidden_states dim)`, *optional*):
-                Conditional embeddings for cross attention layer. If not given, cross-attention defaults to
-                self-attention.
-            timestep ( `torch.long`, *optional*):
-                Optional timestep to be applied as an embedding in AdaLayerNorm's. Used to indicate denoising step.
-            attention_mask (`torch.FloatTensor`, *optional*):
-                Optional attention mask to be applied in Attention.
-            cross_attention_kwargs (`dict`, *optional*):
-                A kwargs dictionary that if specified is passed along to the `AttentionProcessor` as defined under
-                `self.processor` in
-                [diffusers.models.attention_processor](https://github.com/huggingface/diffusers/blob/main/src/diffusers/models/attention_processor.py).
-            return_dict (`bool`, *optional*, defaults to `True`):
-                Whether or not to return a [`models.unets.unet_2d_condition.UNet2DConditionOutput`] instead of a plain tuple.
-
-        Returns:
-            [`~models.transformer_2d.Transformer2DModelOutput`] or `tuple`:
-            [`~models.transformer_2d.Transformer2DModelOutput`] if `return_dict` is True, otherwise a `tuple`. When
-            returning a tuple, the first element is the sample tensor.
-        """
-        input_states = hidden_states
-
-        encoded_states = []
-        tokens_start = 0
-        # attention_mask is not used yet
-        for i in range(2):
-            # for each of the two transformers, pass the corresponding condition tokens
-            condition_state = encoder_hidden_states[:, tokens_start : tokens_start + self.condition_lengths[i]]
-            transformer_index = self.transformer_index_for_condition[i]
-            encoded_state = self.transformers[transformer_index](
-                input_states,
-                encoder_hidden_states=condition_state,
-                timestep=timestep,
-                cross_attention_kwargs=cross_attention_kwargs,
-                return_dict=False,
-            )[0]
-            encoded_states.append(encoded_state - input_states)
-            tokens_start += self.condition_lengths[i]
-
-        output_states = encoded_states[0] * self.mix_ratio + encoded_states[1] * (1 - self.mix_ratio)
-        output_states = output_states + input_states
-
-        if not return_dict:
-            return (output_states,)
-
-        return Transformer2DModelOutput(sample=output_states)
+class DualTransformer2DModel(DualTransformer2DModel):
+    deprecation_message = "Importing `DualTransformer2DModel` from `diffusers.models.dual_transformer_2d` is deprecated and this will be removed in a future version. Please use `from diffusers.models.transformers.dual_transformer_2d import DualTransformer2DModel`, instead."
+    deprecate("DualTransformer2DModel", "0.29", deprecation_message)

src/diffusers/models/prior_transformer.py

-from dataclasses import dataclass
-from typing import Dict, Optional, Union
+from ..utils import deprecate
+from .transformers.prior_transformer import PriorTransformer, PriorTransformerOutput
 
-import torch
-import torch.nn.functional as F
-from torch import nn
 
-from ..configuration_utils import ConfigMixin, register_to_config
-from ..loaders import PeftAdapterMixin, UNet2DConditionLoadersMixin
-from ..utils import BaseOutput
-from .attention import BasicTransformerBlock
-from .attention_processor import (
-    ADDED_KV_ATTENTION_PROCESSORS,
-    CROSS_ATTENTION_PROCESSORS,
-    AttentionProcessor,
-    AttnAddedKVProcessor,
-    AttnProcessor,
-)
-from .embeddings import TimestepEmbedding, Timesteps
-from .modeling_utils import ModelMixin
+class PriorTransformerOutput(PriorTransformerOutput):
+    deprecation_message = "Importing `PriorTransformerOutput` from `diffusers.models.prior_transformer` is deprecated and this will be removed in a future version. Please use `from diffusers.models.transformers.prior_transformer import PriorTransformerOutput`, instead."
+    deprecate("PriorTransformerOutput", "0.29", deprecation_message)
 
 
-@dataclass
-class PriorTransformerOutput(BaseOutput):
-    """
-    The output of [`PriorTransformer`].
-
-    Args:
-        predicted_image_embedding (`torch.FloatTensor` of shape `(batch_size, embedding_dim)`):
-            The predicted CLIP image embedding conditioned on the CLIP text embedding input.
-    """
-
-    predicted_image_embedding: torch.FloatTensor
-
-
-class PriorTransformer(ModelMixin, ConfigMixin, UNet2DConditionLoadersMixin, PeftAdapterMixin):
-    """
-    A Prior Transformer model.
-
-    Parameters:
-        num_attention_heads (`int`, *optional*, defaults to 32): The number of heads to use for multi-head attention.
-        attention_head_dim (`int`, *optional*, defaults to 64): The number of channels in each head.
-        num_layers (`int`, *optional*, defaults to 20): The number of layers of Transformer blocks to use.
-        embedding_dim (`int`, *optional*, defaults to 768): The dimension of the model input `hidden_states`
-        num_embeddings (`int`, *optional*, defaults to 77):
-            The number of embeddings of the model input `hidden_states`
-        additional_embeddings (`int`, *optional*, defaults to 4): The number of additional tokens appended to the
-            projected `hidden_states`. The actual length of the used `hidden_states` is `num_embeddings +
-            additional_embeddings`.
-        dropout (`float`, *optional*, defaults to 0.0): The dropout probability to use.
-        time_embed_act_fn (`str`, *optional*, defaults to 'silu'):
-            The activation function to use to create timestep embeddings.
-        norm_in_type (`str`, *optional*, defaults to None): The normalization layer to apply on hidden states before
-            passing to Transformer blocks. Set it to `None` if normalization is not needed.
-        embedding_proj_norm_type (`str`, *optional*, defaults to None):
-            The normalization layer to apply on the input `proj_embedding`. Set it to `None` if normalization is not
-            needed.
-        encoder_hid_proj_type (`str`, *optional*, defaults to `linear`):
-            The projection layer to apply on the input `encoder_hidden_states`. Set it to `None` if
-            `encoder_hidden_states` is `None`.
-        added_emb_type (`str`, *optional*, defaults to `prd`): Additional embeddings to condition the model.
-            Choose from `prd` or `None`. if choose `prd`, it will prepend a token indicating the (quantized) dot
-            product between the text embedding and image embedding as proposed in the unclip paper
-            https://arxiv.org/abs/2204.06125 If it is `None`, no additional embeddings will be prepended.
-        time_embed_dim (`int, *optional*, defaults to None): The dimension of timestep embeddings.
-            If None, will be set to `num_attention_heads * attention_head_dim`
-        embedding_proj_dim (`int`, *optional*, default to None):
-            The dimension of `proj_embedding`. If None, will be set to `embedding_dim`.
-        clip_embed_dim (`int`, *optional*, default to None):
-            The dimension of the output. If None, will be set to `embedding_dim`.
-    """
-
-    @register_to_config
-    def __init__(
-        self,
-        num_attention_heads: int = 32,
-        attention_head_dim: int = 64,
-        num_layers: int = 20,
-        embedding_dim: int = 768,
-        num_embeddings=77,
-        additional_embeddings=4,
-        dropout: float = 0.0,
-        time_embed_act_fn: str = "silu",
-        norm_in_type: Optional[str] = None,  # layer
-        embedding_proj_norm_type: Optional[str] = None,  # layer
-        encoder_hid_proj_type: Optional[str] = "linear",  # linear
-        added_emb_type: Optional[str] = "prd",  # prd
-        time_embed_dim: Optional[int] = None,
-        embedding_proj_dim: Optional[int] = None,
-        clip_embed_dim: Optional[int] = None,
-    ):
-        super().__init__()
-        self.num_attention_heads = num_attention_heads
-        self.attention_head_dim = attention_head_dim
-        inner_dim = num_attention_heads * attention_head_dim
-        self.additional_embeddings = additional_embeddings
-
-        time_embed_dim = time_embed_dim or inner_dim
-        embedding_proj_dim = embedding_proj_dim or embedding_dim
-        clip_embed_dim = clip_embed_dim or embedding_dim
-
-        self.time_proj = Timesteps(inner_dim, True, 0)
-        self.time_embedding = TimestepEmbedding(inner_dim, time_embed_dim, out_dim=inner_dim, act_fn=time_embed_act_fn)
-
-        self.proj_in = nn.Linear(embedding_dim, inner_dim)
-
-        if embedding_proj_norm_type is None:
-            self.embedding_proj_norm = None
-        elif embedding_proj_norm_type == "layer":
-            self.embedding_proj_norm = nn.LayerNorm(embedding_proj_dim)
-        else:
-            raise ValueError(f"unsupported embedding_proj_norm_type: {embedding_proj_norm_type}")
-
-        self.embedding_proj = nn.Linear(embedding_proj_dim, inner_dim)
-
-        if encoder_hid_proj_type is None:
-            self.encoder_hidden_states_proj = None
-        elif encoder_hid_proj_type == "linear":
-            self.encoder_hidden_states_proj = nn.Linear(embedding_dim, inner_dim)
-        else:
-            raise ValueError(f"unsupported encoder_hid_proj_type: {encoder_hid_proj_type}")
-
-        self.positional_embedding = nn.Parameter(torch.zeros(1, num_embeddings + additional_embeddings, inner_dim))
-
-        if added_emb_type == "prd":
-            self.prd_embedding = nn.Parameter(torch.zeros(1, 1, inner_dim))
-        elif added_emb_type is None:
-            self.prd_embedding = None
-        else:
-            raise ValueError(
-                f"`added_emb_type`: {added_emb_type} is not supported. Make sure to choose one of `'prd'` or `None`."
-            )
-
-        self.transformer_blocks = nn.ModuleList(
-            [
-                BasicTransformerBlock(
-                    inner_dim,
-                    num_attention_heads,
-                    attention_head_dim,
-                    dropout=dropout,
-                    activation_fn="gelu",
-                    attention_bias=True,
-                )
-                for d in range(num_layers)
-            ]
-        )
-
-        if norm_in_type == "layer":
-            self.norm_in = nn.LayerNorm(inner_dim)
-        elif norm_in_type is None:
-            self.norm_in = None
-        else:
-            raise ValueError(f"Unsupported norm_in_type: {norm_in_type}.")
-
-        self.norm_out = nn.LayerNorm(inner_dim)
-
-        self.proj_to_clip_embeddings = nn.Linear(inner_dim, clip_embed_dim)
-
-        causal_attention_mask = torch.full(
-            [num_embeddings + additional_embeddings, num_embeddings + additional_embeddings], -10000.0
-        )
-        causal_attention_mask.triu_(1)
-        causal_attention_mask = causal_attention_mask[None, ...]
-        self.register_buffer("causal_attention_mask", causal_attention_mask, persistent=False)
-
-        self.clip_mean = nn.Parameter(torch.zeros(1, clip_embed_dim))
-        self.clip_std = nn.Parameter(torch.zeros(1, clip_embed_dim))
-
-    @property
-    # Copied from diffusers.models.unets.unet_2d_condition.UNet2DConditionModel.attn_processors
-    def attn_processors(self) -> Dict[str, AttentionProcessor]:
-        r"""
-        Returns:
-            `dict` of attention processors: A dictionary containing all attention processors used in the model with
-            indexed by its weight name.
-        """
-        # set recursively
-        processors = {}
-
-        def fn_recursive_add_processors(name: str, module: torch.nn.Module, processors: Dict[str, AttentionProcessor]):
-            if hasattr(module, "get_processor"):
-                processors[f"{name}.processor"] = module.get_processor(return_deprecated_lora=True)
-
-            for sub_name, child in module.named_children():
-                fn_recursive_add_processors(f"{name}.{sub_name}", child, processors)
-
-            return processors
-
-        for name, module in self.named_children():
-            fn_recursive_add_processors(name, module, processors)
-
-        return processors
-
-    # Copied from diffusers.models.unets.unet_2d_condition.UNet2DConditionModel.set_attn_processor
-    def set_attn_processor(self, processor: Union[AttentionProcessor, Dict[str, AttentionProcessor]]):
-        r"""
-        Sets the attention processor to use to compute attention.
-
-        Parameters:
-            processor (`dict` of `AttentionProcessor` or only `AttentionProcessor`):
-                The instantiated processor class or a dictionary of processor classes that will be set as the processor
-                for **all** `Attention` layers.
-
-                If `processor` is a dict, the key needs to define the path to the corresponding cross attention
-                processor. This is strongly recommended when setting trainable attention processors.
-
-        """
-        count = len(self.attn_processors.keys())
-
-        if isinstance(processor, dict) and len(processor) != count:
-            raise ValueError(
-                f"A dict of processors was passed, but the number of processors {len(processor)} does not match the"
-                f" number of attention layers: {count}. Please make sure to pass {count} processor classes."
-            )
-
-        def fn_recursive_attn_processor(name: str, module: torch.nn.Module, processor):
-            if hasattr(module, "set_processor"):
-                if not isinstance(processor, dict):
-                    module.set_processor(processor)
-                else:
-                    module.set_processor(processor.pop(f"{name}.processor"))
-
-            for sub_name, child in module.named_children():
-                fn_recursive_attn_processor(f"{name}.{sub_name}", child, processor)
-
-        for name, module in self.named_children():
-            fn_recursive_attn_processor(name, module, processor)
-
-    # Copied from diffusers.models.unets.unet_2d_condition.UNet2DConditionModel.set_default_attn_processor
-    def set_default_attn_processor(self):
-        """
-        Disables custom attention processors and sets the default attention implementation.
-        """
-        if all(proc.__class__ in ADDED_KV_ATTENTION_PROCESSORS for proc in self.attn_processors.values()):
-            processor = AttnAddedKVProcessor()
-        elif all(proc.__class__ in CROSS_ATTENTION_PROCESSORS for proc in self.attn_processors.values()):
-            processor = AttnProcessor()
-        else:
-            raise ValueError(
-                f"Cannot call `set_default_attn_processor` when attention processors are of type {next(iter(self.attn_processors.values()))}"
-            )
-
-        self.set_attn_processor(processor)
-
-    def forward(
-        self,
-        hidden_states,
-        timestep: Union[torch.Tensor, float, int],
-        proj_embedding: torch.FloatTensor,
-        encoder_hidden_states: Optional[torch.FloatTensor] = None,
-        attention_mask: Optional[torch.BoolTensor] = None,
-        return_dict: bool = True,
-    ):
-        """
-        The [`PriorTransformer`] forward method.
-
-        Args:
-            hidden_states (`torch.FloatTensor` of shape `(batch_size, embedding_dim)`):
-                The currently predicted image embeddings.
-            timestep (`torch.LongTensor`):
-                Current denoising step.
-            proj_embedding (`torch.FloatTensor` of shape `(batch_size, embedding_dim)`):
-                Projected embedding vector the denoising process is conditioned on.
-            encoder_hidden_states (`torch.FloatTensor` of shape `(batch_size, num_embeddings, embedding_dim)`):
-                Hidden states of the text embeddings the denoising process is conditioned on.
-            attention_mask (`torch.BoolTensor` of shape `(batch_size, num_embeddings)`):
-                Text mask for the text embeddings.
-            return_dict (`bool`, *optional*, defaults to `True`):
-                Whether or not to return a [`~models.prior_transformer.PriorTransformerOutput`] instead of a plain
-                tuple.
-
-        Returns:
-            [`~models.prior_transformer.PriorTransformerOutput`] or `tuple`:
-                If return_dict is True, a [`~models.prior_transformer.PriorTransformerOutput`] is returned, otherwise a
-                tuple is returned where the first element is the sample tensor.
-        """
-        batch_size = hidden_states.shape[0]
-
-        timesteps = timestep
-        if not torch.is_tensor(timesteps):
-            timesteps = torch.tensor([timesteps], dtype=torch.long, device=hidden_states.device)
-        elif torch.is_tensor(timesteps) and len(timesteps.shape) == 0:
-            timesteps = timesteps[None].to(hidden_states.device)
-
-        # broadcast to batch dimension in a way that's compatible with ONNX/Core ML
-        timesteps = timesteps * torch.ones(batch_size, dtype=timesteps.dtype, device=timesteps.device)
-
-        timesteps_projected = self.time_proj(timesteps)
-
-        # timesteps does not contain any weights and will always return f32 tensors
-        # but time_embedding might be fp16, so we need to cast here.
-        timesteps_projected = timesteps_projected.to(dtype=self.dtype)
-        time_embeddings = self.time_embedding(timesteps_projected)
-
-        if self.embedding_proj_norm is not None:
-            proj_embedding = self.embedding_proj_norm(proj_embedding)
-
-        proj_embeddings = self.embedding_proj(proj_embedding)
-        if self.encoder_hidden_states_proj is not None and encoder_hidden_states is not None:
-            encoder_hidden_states = self.encoder_hidden_states_proj(encoder_hidden_states)
-        elif self.encoder_hidden_states_proj is not None and encoder_hidden_states is None:
-            raise ValueError("`encoder_hidden_states_proj` requires `encoder_hidden_states` to be set")
-
-        hidden_states = self.proj_in(hidden_states)
-
-        positional_embeddings = self.positional_embedding.to(hidden_states.dtype)
-
-        additional_embeds = []
-        additional_embeddings_len = 0
-
-        if encoder_hidden_states is not None:
-            additional_embeds.append(encoder_hidden_states)
-            additional_embeddings_len += encoder_hidden_states.shape[1]
-
-        if len(proj_embeddings.shape) == 2:
-            proj_embeddings = proj_embeddings[:, None, :]
-
-        if len(hidden_states.shape) == 2:
-            hidden_states = hidden_states[:, None, :]
-
-        additional_embeds = additional_embeds + [
-            proj_embeddings,
-            time_embeddings[:, None, :],
-            hidden_states,
-        ]
-
-        if self.prd_embedding is not None:
-            prd_embedding = self.prd_embedding.to(hidden_states.dtype).expand(batch_size, -1, -1)
-            additional_embeds.append(prd_embedding)
-
-        hidden_states = torch.cat(
-            additional_embeds,
-            dim=1,
-        )
-
-        # Allow positional_embedding to not include the `addtional_embeddings` and instead pad it with zeros for these additional tokens
-        additional_embeddings_len = additional_embeddings_len + proj_embeddings.shape[1] + 1
-        if positional_embeddings.shape[1] < hidden_states.shape[1]:
-            positional_embeddings = F.pad(
-                positional_embeddings,
-                (
-                    0,
-                    0,
-                    additional_embeddings_len,
-                    self.prd_embedding.shape[1] if self.prd_embedding is not None else 0,
-                ),
-                value=0.0,
-            )
-
-        hidden_states = hidden_states + positional_embeddings
-
-        if attention_mask is not None:
-            attention_mask = (1 - attention_mask.to(hidden_states.dtype)) * -10000.0
-            attention_mask = F.pad(attention_mask, (0, self.additional_embeddings), value=0.0)
-            attention_mask = (attention_mask[:, None, :] + self.causal_attention_mask).to(hidden_states.dtype)
-            attention_mask = attention_mask.repeat_interleave(self.config.num_attention_heads, dim=0)
-
-        if self.norm_in is not None:
-            hidden_states = self.norm_in(hidden_states)
-
-        for block in self.transformer_blocks:
-            hidden_states = block(hidden_states, attention_mask=attention_mask)
-
-        hidden_states = self.norm_out(hidden_states)
-
-        if self.prd_embedding is not None:
-            hidden_states = hidden_states[:, -1]
-        else:
-            hidden_states = hidden_states[:, additional_embeddings_len:]
-
-        predicted_image_embedding = self.proj_to_clip_embeddings(hidden_states)
-
-        if not return_dict:
-            return (predicted_image_embedding,)
-
-        return PriorTransformerOutput(predicted_image_embedding=predicted_image_embedding)
-
-    def post_process_latents(self, prior_latents):
-        prior_latents = (prior_latents * self.clip_std) + self.clip_mean
-        return prior_latents
+class PriorTransformer(PriorTransformer):
+    deprecation_message = "Importing `PriorTransformer` from `diffusers.models.prior_transformer` is deprecated and this will be removed in a future version. Please use `from diffusers.models.transformers.prior_transformer import PriorTransformer`, instead."
+    deprecate("PriorTransformer", "0.29", deprecation_message)

src/diffusers/models/t5_film_transformer.py

@@ -11,428 +11,60 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-import math
-from typing import Optional, Tuple
+from ..utils import deprecate
+from .transformers.t5_film_transformer import (
+    DecoderLayer,
+    NewGELUActivation,
+    T5DenseGatedActDense,
+    T5FilmDecoder,
+    T5FiLMLayer,
+    T5LayerCrossAttention,
+    T5LayerFFCond,
+    T5LayerNorm,
+    T5LayerSelfAttentionCond,
+)
 
-import torch
-from torch import nn
 
-from ..configuration_utils import ConfigMixin, register_to_config
-from .attention_processor import Attention
-from .embeddings import get_timestep_embedding
-from .modeling_utils import ModelMixin
+class T5FilmDecoder(T5FilmDecoder):
+    deprecation_message = "Importing `T5FilmDecoder` from `diffusers.models.t5_film_transformer` is deprecated and this will be removed in a future version. Please use `from diffusers.models.transformers.t5_film_transformer import T5FilmDecoder`, instead."
+    deprecate("T5FilmDecoder", "0.29", deprecation_message)
 
 
-class T5FilmDecoder(ModelMixin, ConfigMixin):
-    r"""
-    T5 style decoder with FiLM conditioning.
+class DecoderLayer(DecoderLayer):
+    deprecation_message = "Importing `DecoderLayer` from `diffusers.models.t5_film_transformer` is deprecated and this will be removed in a future version. Please use `from diffusers.models.transformers.t5_film_transformer import DecoderLayer`, instead."
+    deprecate("DecoderLayer", "0.29", deprecation_message)
 
-    Args:
-        input_dims (`int`, *optional*, defaults to `128`):
-            The number of input dimensions.
-        targets_length (`int`, *optional*, defaults to `256`):
-            The length of the targets.
-        d_model (`int`, *optional*, defaults to `768`):
-            Size of the input hidden states.
-        num_layers (`int`, *optional*, defaults to `12`):
-            The number of `DecoderLayer`'s to use.
-        num_heads (`int`, *optional*, defaults to `12`):
-            The number of attention heads to use.
-        d_kv (`int`, *optional*, defaults to `64`):
-            Size of the key-value projection vectors.
-        d_ff (`int`, *optional*, defaults to `2048`):
-            The number of dimensions in the intermediate feed-forward layer of `DecoderLayer`'s.
-        dropout_rate (`float`, *optional*, defaults to `0.1`):
-            Dropout probability.
-    """
 
-    @register_to_config
-    def __init__(
-        self,
-        input_dims: int = 128,
-        targets_length: int = 256,
-        max_decoder_noise_time: float = 2000.0,
-        d_model: int = 768,
-        num_layers: int = 12,
-        num_heads: int = 12,
-        d_kv: int = 64,
-        d_ff: int = 2048,
-        dropout_rate: float = 0.1,
-    ):
-        super().__init__()
+class T5LayerSelfAttentionCond(T5LayerSelfAttentionCond):
+    deprecation_message = "Importing `T5LayerSelfAttentionCond` from `diffusers.models.t5_film_transformer` is deprecated and this will be removed in a future version. Please use `from diffusers.models.transformers.t5_film_transformer import T5LayerSelfAttentionCond`, instead."
+    deprecate("T5LayerSelfAttentionCond", "0.29", deprecation_message)
 
-        self.conditioning_emb = nn.Sequential(
-            nn.Linear(d_model, d_model * 4, bias=False),
-            nn.SiLU(),
-            nn.Linear(d_model * 4, d_model * 4, bias=False),
-            nn.SiLU(),
-        )
 
-        self.position_encoding = nn.Embedding(targets_length, d_model)
-        self.position_encoding.weight.requires_grad = False
+class T5LayerCrossAttention(T5LayerCrossAttention):
+    deprecation_message = "Importing `T5LayerCrossAttention` from `diffusers.models.t5_film_transformer` is deprecated and this will be removed in a future version. Please use `from diffusers.models.transformers.t5_film_transformer import T5LayerCrossAttention`, instead."
+    deprecate("T5LayerCrossAttention", "0.29", deprecation_message)
 
-        self.continuous_inputs_projection = nn.Linear(input_dims, d_model, bias=False)
 
-        self.dropout = nn.Dropout(p=dropout_rate)
+class T5LayerFFCond(T5LayerFFCond):
+    deprecation_message = "Importing `T5LayerFFCond` from `diffusers.models.t5_film_transformer` is deprecated and this will be removed in a future version. Please use `from diffusers.models.transformers.t5_film_transformer import T5LayerFFCond`, instead."
+    deprecate("T5LayerFFCond", "0.29", deprecation_message)
 
-        self.decoders = nn.ModuleList()
-        for lyr_num in range(num_layers):
-            # FiLM conditional T5 decoder
-            lyr = DecoderLayer(d_model=d_model, d_kv=d_kv, num_heads=num_heads, d_ff=d_ff, dropout_rate=dropout_rate)
-            self.decoders.append(lyr)
 
-        self.decoder_norm = T5LayerNorm(d_model)
+class T5DenseGatedActDense(T5DenseGatedActDense):
+    deprecation_message = "Importing `T5DenseGatedActDense` from `diffusers.models.t5_film_transformer` is deprecated and this will be removed in a future version. Please use `from diffusers.models.transformers.t5_film_transformer import T5DenseGatedActDense`, instead."
+    deprecate("T5DenseGatedActDense", "0.29", deprecation_message)
 
-        self.post_dropout = nn.Dropout(p=dropout_rate)
-        self.spec_out = nn.Linear(d_model, input_dims, bias=False)
 
-    def encoder_decoder_mask(self, query_input: torch.FloatTensor, key_input: torch.FloatTensor) -> torch.FloatTensor:
-        mask = torch.mul(query_input.unsqueeze(-1), key_input.unsqueeze(-2))
-        return mask.unsqueeze(-3)
+class T5LayerNorm(T5LayerNorm):
+    deprecation_message = "Importing `T5LayerNorm` from `diffusers.models.t5_film_transformer` is deprecated and this will be removed in a future version. Please use `from diffusers.models.transformers.t5_film_transformer import T5LayerNorm`, instead."
+    deprecate("T5LayerNorm", "0.29", deprecation_message)
 
-    def forward(self, encodings_and_masks, decoder_input_tokens, decoder_noise_time):
-        batch, _, _ = decoder_input_tokens.shape
-        assert decoder_noise_time.shape == (batch,)
 
-        # decoder_noise_time is in [0, 1), so rescale to expected timing range.
-        time_steps = get_timestep_embedding(
-            decoder_noise_time * self.config.max_decoder_noise_time,
-            embedding_dim=self.config.d_model,
-            max_period=self.config.max_decoder_noise_time,
-        ).to(dtype=self.dtype)
+class NewGELUActivation(NewGELUActivation):
+    deprecation_message = "Importing `T5LayerNorm` from `diffusers.models.t5_film_transformer` is deprecated and this will be removed in a future version. Please use `from diffusers.models.transformers.t5_film_transformer import NewGELUActivation`, instead."
+    deprecate("NewGELUActivation", "0.29", deprecation_message)
 
-        conditioning_emb = self.conditioning_emb(time_steps).unsqueeze(1)
 
-        assert conditioning_emb.shape == (batch, 1, self.config.d_model * 4)
-
-        seq_length = decoder_input_tokens.shape[1]
-
-        # If we want to use relative positions for audio context, we can just offset
-        # this sequence by the length of encodings_and_masks.
-        decoder_positions = torch.broadcast_to(
-            torch.arange(seq_length, device=decoder_input_tokens.device),
-            (batch, seq_length),
-        )
-
-        position_encodings = self.position_encoding(decoder_positions)
-
-        inputs = self.continuous_inputs_projection(decoder_input_tokens)
-        inputs += position_encodings
-        y = self.dropout(inputs)
-
-        # decoder: No padding present.
-        decoder_mask = torch.ones(
-            decoder_input_tokens.shape[:2], device=decoder_input_tokens.device, dtype=inputs.dtype
-        )
-
-        # Translate encoding masks to encoder-decoder masks.
-        encodings_and_encdec_masks = [(x, self.encoder_decoder_mask(decoder_mask, y)) for x, y in encodings_and_masks]
-
-        # cross attend style: concat encodings
-        encoded = torch.cat([x[0] for x in encodings_and_encdec_masks], dim=1)
-        encoder_decoder_mask = torch.cat([x[1] for x in encodings_and_encdec_masks], dim=-1)
-
-        for lyr in self.decoders:
-            y = lyr(
-                y,
-                conditioning_emb=conditioning_emb,
-                encoder_hidden_states=encoded,
-                encoder_attention_mask=encoder_decoder_mask,
-            )[0]
-
-        y = self.decoder_norm(y)
-        y = self.post_dropout(y)
-
-        spec_out = self.spec_out(y)
-        return spec_out
-
-
-class DecoderLayer(nn.Module):
-    r"""
-    T5 decoder layer.
-
-    Args:
-        d_model (`int`):
-            Size of the input hidden states.
-        d_kv (`int`):
-            Size of the key-value projection vectors.
-        num_heads (`int`):
-            Number of attention heads.
-        d_ff (`int`):
-            Size of the intermediate feed-forward layer.
-        dropout_rate (`float`):
-            Dropout probability.
-        layer_norm_epsilon (`float`, *optional*, defaults to `1e-6`):
-            A small value used for numerical stability to avoid dividing by zero.
-    """
-
-    def __init__(
-        self, d_model: int, d_kv: int, num_heads: int, d_ff: int, dropout_rate: float, layer_norm_epsilon: float = 1e-6
-    ):
-        super().__init__()
-        self.layer = nn.ModuleList()
-
-        # cond self attention: layer 0
-        self.layer.append(
-            T5LayerSelfAttentionCond(d_model=d_model, d_kv=d_kv, num_heads=num_heads, dropout_rate=dropout_rate)
-        )
-
-        # cross attention: layer 1
-        self.layer.append(
-            T5LayerCrossAttention(
-                d_model=d_model,
-                d_kv=d_kv,
-                num_heads=num_heads,
-                dropout_rate=dropout_rate,
-                layer_norm_epsilon=layer_norm_epsilon,
-            )
-        )
-
-        # Film Cond MLP + dropout: last layer
-        self.layer.append(
-            T5LayerFFCond(d_model=d_model, d_ff=d_ff, dropout_rate=dropout_rate, layer_norm_epsilon=layer_norm_epsilon)
-        )
-
-    def forward(
-        self,
-        hidden_states: torch.FloatTensor,
-        conditioning_emb: Optional[torch.FloatTensor] = None,
-        attention_mask: Optional[torch.FloatTensor] = None,
-        encoder_hidden_states: Optional[torch.Tensor] = None,
-        encoder_attention_mask: Optional[torch.Tensor] = None,
-        encoder_decoder_position_bias=None,
-    ) -> Tuple[torch.FloatTensor]:
-        hidden_states = self.layer[0](
-            hidden_states,
-            conditioning_emb=conditioning_emb,
-            attention_mask=attention_mask,
-        )
-
-        if encoder_hidden_states is not None:
-            encoder_extended_attention_mask = torch.where(encoder_attention_mask > 0, 0, -1e10).to(
-                encoder_hidden_states.dtype
-            )
-
-            hidden_states = self.layer[1](
-                hidden_states,
-                key_value_states=encoder_hidden_states,
-                attention_mask=encoder_extended_attention_mask,
-            )
-
-        # Apply Film Conditional Feed Forward layer
-        hidden_states = self.layer[-1](hidden_states, conditioning_emb)
-
-        return (hidden_states,)
-
-
-class T5LayerSelfAttentionCond(nn.Module):
-    r"""
-    T5 style self-attention layer with conditioning.
-
-    Args:
-        d_model (`int`):
-            Size of the input hidden states.
-        d_kv (`int`):
-            Size of the key-value projection vectors.
-        num_heads (`int`):
-            Number of attention heads.
-        dropout_rate (`float`):
-            Dropout probability.
-    """
-
-    def __init__(self, d_model: int, d_kv: int, num_heads: int, dropout_rate: float):
-        super().__init__()
-        self.layer_norm = T5LayerNorm(d_model)
-        self.FiLMLayer = T5FiLMLayer(in_features=d_model * 4, out_features=d_model)
-        self.attention = Attention(query_dim=d_model, heads=num_heads, dim_head=d_kv, out_bias=False, scale_qk=False)
-        self.dropout = nn.Dropout(dropout_rate)
-
-    def forward(
-        self,
-        hidden_states: torch.FloatTensor,
-        conditioning_emb: Optional[torch.FloatTensor] = None,
-        attention_mask: Optional[torch.FloatTensor] = None,
-    ) -> torch.FloatTensor:
-        # pre_self_attention_layer_norm
-        normed_hidden_states = self.layer_norm(hidden_states)
-
-        if conditioning_emb is not None:
-            normed_hidden_states = self.FiLMLayer(normed_hidden_states, conditioning_emb)
-
-        # Self-attention block
-        attention_output = self.attention(normed_hidden_states)
-
-        hidden_states = hidden_states + self.dropout(attention_output)
-
-        return hidden_states
-
-
-class T5LayerCrossAttention(nn.Module):
-    r"""
-    T5 style cross-attention layer.
-
-    Args:
-        d_model (`int`):
-            Size of the input hidden states.
-        d_kv (`int`):
-            Size of the key-value projection vectors.
-        num_heads (`int`):
-            Number of attention heads.
-        dropout_rate (`float`):
-            Dropout probability.
-        layer_norm_epsilon (`float`):
-            A small value used for numerical stability to avoid dividing by zero.
-    """
-
-    def __init__(self, d_model: int, d_kv: int, num_heads: int, dropout_rate: float, layer_norm_epsilon: float):
-        super().__init__()
-        self.attention = Attention(query_dim=d_model, heads=num_heads, dim_head=d_kv, out_bias=False, scale_qk=False)
-        self.layer_norm = T5LayerNorm(d_model, eps=layer_norm_epsilon)
-        self.dropout = nn.Dropout(dropout_rate)
-
-    def forward(
-        self,
-        hidden_states: torch.FloatTensor,
-        key_value_states: Optional[torch.FloatTensor] = None,
-        attention_mask: Optional[torch.FloatTensor] = None,
-    ) -> torch.FloatTensor:
-        normed_hidden_states = self.layer_norm(hidden_states)
-        attention_output = self.attention(
-            normed_hidden_states,
-            encoder_hidden_states=key_value_states,
-            attention_mask=attention_mask.squeeze(1),
-        )
-        layer_output = hidden_states + self.dropout(attention_output)
-        return layer_output
-
-
-class T5LayerFFCond(nn.Module):
-    r"""
-    T5 style feed-forward conditional layer.
-
-    Args:
-        d_model (`int`):
-            Size of the input hidden states.
-        d_ff (`int`):
-            Size of the intermediate feed-forward layer.
-        dropout_rate (`float`):
-            Dropout probability.
-        layer_norm_epsilon (`float`):
-            A small value used for numerical stability to avoid dividing by zero.
-    """
-
-    def __init__(self, d_model: int, d_ff: int, dropout_rate: float, layer_norm_epsilon: float):
-        super().__init__()
-        self.DenseReluDense = T5DenseGatedActDense(d_model=d_model, d_ff=d_ff, dropout_rate=dropout_rate)
-        self.film = T5FiLMLayer(in_features=d_model * 4, out_features=d_model)
-        self.layer_norm = T5LayerNorm(d_model, eps=layer_norm_epsilon)
-        self.dropout = nn.Dropout(dropout_rate)
-
-    def forward(
-        self, hidden_states: torch.FloatTensor, conditioning_emb: Optional[torch.FloatTensor] = None
-    ) -> torch.FloatTensor:
-        forwarded_states = self.layer_norm(hidden_states)
-        if conditioning_emb is not None:
-            forwarded_states = self.film(forwarded_states, conditioning_emb)
-
-        forwarded_states = self.DenseReluDense(forwarded_states)
-        hidden_states = hidden_states + self.dropout(forwarded_states)
-        return hidden_states
-
-
-class T5DenseGatedActDense(nn.Module):
-    r"""
-    T5 style feed-forward layer with gated activations and dropout.
-
-    Args:
-        d_model (`int`):
-            Size of the input hidden states.
-        d_ff (`int`):
-            Size of the intermediate feed-forward layer.
-        dropout_rate (`float`):
-            Dropout probability.
-    """
-
-    def __init__(self, d_model: int, d_ff: int, dropout_rate: float):
-        super().__init__()
-        self.wi_0 = nn.Linear(d_model, d_ff, bias=False)
-        self.wi_1 = nn.Linear(d_model, d_ff, bias=False)
-        self.wo = nn.Linear(d_ff, d_model, bias=False)
-        self.dropout = nn.Dropout(dropout_rate)
-        self.act = NewGELUActivation()
-
-    def forward(self, hidden_states: torch.FloatTensor) -> torch.FloatTensor:
-        hidden_gelu = self.act(self.wi_0(hidden_states))
-        hidden_linear = self.wi_1(hidden_states)
-        hidden_states = hidden_gelu * hidden_linear
-        hidden_states = self.dropout(hidden_states)
-
-        hidden_states = self.wo(hidden_states)
-        return hidden_states
-
-
-class T5LayerNorm(nn.Module):
-    r"""
-    T5 style layer normalization module.
-
-    Args:
-        hidden_size (`int`):
-            Size of the input hidden states.
-        eps (`float`, `optional`, defaults to `1e-6`):
-            A small value used for numerical stability to avoid dividing by zero.
-    """
-
-    def __init__(self, hidden_size: int, eps: float = 1e-6):
-        """
-        Construct a layernorm module in the T5 style. No bias and no subtraction of mean.
-        """
-        super().__init__()
-        self.weight = nn.Parameter(torch.ones(hidden_size))
-        self.variance_epsilon = eps
-
-    def forward(self, hidden_states: torch.FloatTensor) -> torch.FloatTensor:
-        # T5 uses a layer_norm which only scales and doesn't shift, which is also known as Root Mean
-        # Square Layer Normalization https://arxiv.org/abs/1910.07467 thus variance is calculated
-        # w/o mean and there is no bias. Additionally we want to make sure that the accumulation for
-        # half-precision inputs is done in fp32
-
-        variance = hidden_states.to(torch.float32).pow(2).mean(-1, keepdim=True)
-        hidden_states = hidden_states * torch.rsqrt(variance + self.variance_epsilon)
-
-        # convert into half-precision if necessary
-        if self.weight.dtype in [torch.float16, torch.bfloat16]:
-            hidden_states = hidden_states.to(self.weight.dtype)
-
-        return self.weight * hidden_states
-
-
-class NewGELUActivation(nn.Module):
-    """
-    Implementation of the GELU activation function currently in Google BERT repo (identical to OpenAI GPT). Also see
-    the Gaussian Error Linear Units paper: https://arxiv.org/abs/1606.08415
-    """
-
-    def forward(self, input: torch.Tensor) -> torch.Tensor:
-        return 0.5 * input * (1.0 + torch.tanh(math.sqrt(2.0 / math.pi) * (input + 0.044715 * torch.pow(input, 3.0))))
-
-
-class T5FiLMLayer(nn.Module):
-    """
-    T5 style FiLM Layer.
-
-    Args:
-        in_features (`int`):
-            Number of input features.
-        out_features (`int`):
-            Number of output features.
-    """
-
-    def __init__(self, in_features: int, out_features: int):
-        super().__init__()
-        self.scale_bias = nn.Linear(in_features, out_features * 2, bias=False)
-
-    def forward(self, x: torch.FloatTensor, conditioning_emb: torch.FloatTensor) -> torch.FloatTensor:
-        emb = self.scale_bias(conditioning_emb)
-        scale, shift = torch.chunk(emb, 2, -1)
-        x = x * (1 + scale) + shift
-        return x
+class T5FiLMLayer(T5FiLMLayer):
+    deprecation_message = "Importing `T5FiLMLayer` from `diffusers.models.t5_film_transformer` is deprecated and this will be removed in a future version. Please use `from diffusers.models.transformers.t5_film_transformer import T5FiLMLayer`, instead."
+    deprecate("T5FiLMLayer", "0.29", deprecation_message)

src/diffusers/models/transformer_2d.py

@@ -11,449 +11,15 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-from dataclasses import dataclass
-from typing import Any, Dict, Optional
+from ..utils import deprecate
+from .transformers.transformer_2d import Transformer2DModel, Transformer2DModelOutput
 
-import torch
-import torch.nn.functional as F
-from torch import nn
 
-from ..configuration_utils import ConfigMixin, register_to_config
-from ..models.embeddings import ImagePositionalEmbeddings
-from ..utils import USE_PEFT_BACKEND, BaseOutput, deprecate, is_torch_version
-from .attention import BasicTransformerBlock
-from .embeddings import PatchEmbed, PixArtAlphaTextProjection
-from .lora import LoRACompatibleConv, LoRACompatibleLinear
-from .modeling_utils import ModelMixin
-from .normalization import AdaLayerNormSingle
+class Transformer2DModelOutput(Transformer2DModelOutput):
+    deprecation_message = "Importing `Transformer2DModelOutput` from `diffusers.models.transformer_2d` is deprecated and this will be removed in a future version. Please use `from diffusers.models.transformers.transformer_2d import Transformer2DModelOutput`, instead."
+    deprecate("Transformer2DModelOutput", "0.29", deprecation_message)
 
 
-@dataclass
-class Transformer2DModelOutput(BaseOutput):
-    """
-    The output of [`Transformer2DModel`].
-
-    Args:
-        sample (`torch.FloatTensor` of shape `(batch_size, num_channels, height, width)` or `(batch size, num_vector_embeds - 1, num_latent_pixels)` if [`Transformer2DModel`] is discrete):
-            The hidden states output conditioned on the `encoder_hidden_states` input. If discrete, returns probability
-            distributions for the unnoised latent pixels.
-    """
-
-    sample: torch.FloatTensor
-
-
-class Transformer2DModel(ModelMixin, ConfigMixin):
-    """
-    A 2D Transformer model for image-like data.
-
-    Parameters:
-        num_attention_heads (`int`, *optional*, defaults to 16): The number of heads to use for multi-head attention.
-        attention_head_dim (`int`, *optional*, defaults to 88): The number of channels in each head.
-        in_channels (`int`, *optional*):
-            The number of channels in the input and output (specify if the input is **continuous**).
-        num_layers (`int`, *optional*, defaults to 1): The number of layers of Transformer blocks to use.
-        dropout (`float`, *optional*, defaults to 0.0): The dropout probability to use.
-        cross_attention_dim (`int`, *optional*): The number of `encoder_hidden_states` dimensions to use.
-        sample_size (`int`, *optional*): The width of the latent images (specify if the input is **discrete**).
-            This is fixed during training since it is used to learn a number of position embeddings.
-        num_vector_embeds (`int`, *optional*):
-            The number of classes of the vector embeddings of the latent pixels (specify if the input is **discrete**).
-            Includes the class for the masked latent pixel.
-        activation_fn (`str`, *optional*, defaults to `"geglu"`): Activation function to use in feed-forward.
-        num_embeds_ada_norm ( `int`, *optional*):
-            The number of diffusion steps used during training. Pass if at least one of the norm_layers is
-            `AdaLayerNorm`. This is fixed during training since it is used to learn a number of embeddings that are
-            added to the hidden states.
-
-            During inference, you can denoise for up to but not more steps than `num_embeds_ada_norm`.
-        attention_bias (`bool`, *optional*):
-            Configure if the `TransformerBlocks` attention should contain a bias parameter.
-    """
-
-    _supports_gradient_checkpointing = True
-
-    @register_to_config
-    def __init__(
-        self,
-        num_attention_heads: int = 16,
-        attention_head_dim: int = 88,
-        in_channels: Optional[int] = None,
-        out_channels: Optional[int] = None,
-        num_layers: int = 1,
-        dropout: float = 0.0,
-        norm_num_groups: int = 32,
-        cross_attention_dim: Optional[int] = None,
-        attention_bias: bool = False,
-        sample_size: Optional[int] = None,
-        num_vector_embeds: Optional[int] = None,
-        patch_size: Optional[int] = None,
-        activation_fn: str = "geglu",
-        num_embeds_ada_norm: Optional[int] = None,
-        use_linear_projection: bool = False,
-        only_cross_attention: bool = False,
-        double_self_attention: bool = False,
-        upcast_attention: bool = False,
-        norm_type: str = "layer_norm",
-        norm_elementwise_affine: bool = True,
-        norm_eps: float = 1e-5,
-        attention_type: str = "default",
-        caption_channels: int = None,
-    ):
-        super().__init__()
-        self.use_linear_projection = use_linear_projection
-        self.num_attention_heads = num_attention_heads
-        self.attention_head_dim = attention_head_dim
-        inner_dim = num_attention_heads * attention_head_dim
-
-        conv_cls = nn.Conv2d if USE_PEFT_BACKEND else LoRACompatibleConv
-        linear_cls = nn.Linear if USE_PEFT_BACKEND else LoRACompatibleLinear
-
-        # 1. Transformer2DModel can process both standard continuous images of shape `(batch_size, num_channels, width, height)` as well as quantized image embeddings of shape `(batch_size, num_image_vectors)`
-        # Define whether input is continuous or discrete depending on configuration
-        self.is_input_continuous = (in_channels is not None) and (patch_size is None)
-        self.is_input_vectorized = num_vector_embeds is not None
-        self.is_input_patches = in_channels is not None and patch_size is not None
-
-        if norm_type == "layer_norm" and num_embeds_ada_norm is not None:
-            deprecation_message = (
-                f"The configuration file of this model: {self.__class__} is outdated. `norm_type` is either not set or"
-                " incorrectly set to `'layer_norm'`.Make sure to set `norm_type` to `'ada_norm'` in the config."
-                " Please make sure to update the config accordingly as leaving `norm_type` might led to incorrect"
-                " results in future versions. If you have downloaded this checkpoint from the Hugging Face Hub, it"
-                " would be very nice if you could open a Pull request for the `transformer/config.json` file"
-            )
-            deprecate("norm_type!=num_embeds_ada_norm", "1.0.0", deprecation_message, standard_warn=False)
-            norm_type = "ada_norm"
-
-        if self.is_input_continuous and self.is_input_vectorized:
-            raise ValueError(
-                f"Cannot define both `in_channels`: {in_channels} and `num_vector_embeds`: {num_vector_embeds}. Make"
-                " sure that either `in_channels` or `num_vector_embeds` is None."
-            )
-        elif self.is_input_vectorized and self.is_input_patches:
-            raise ValueError(
-                f"Cannot define both `num_vector_embeds`: {num_vector_embeds} and `patch_size`: {patch_size}. Make"
-                " sure that either `num_vector_embeds` or `num_patches` is None."
-            )
-        elif not self.is_input_continuous and not self.is_input_vectorized and not self.is_input_patches:
-            raise ValueError(
-                f"Has to define `in_channels`: {in_channels}, `num_vector_embeds`: {num_vector_embeds}, or patch_size:"
-                f" {patch_size}. Make sure that `in_channels`, `num_vector_embeds` or `num_patches` is not None."
-            )
-
-        # 2. Define input layers
-        if self.is_input_continuous:
-            self.in_channels = in_channels
-
-            self.norm = torch.nn.GroupNorm(num_groups=norm_num_groups, num_channels=in_channels, eps=1e-6, affine=True)
-            if use_linear_projection:
-                self.proj_in = linear_cls(in_channels, inner_dim)
-            else:
-                self.proj_in = conv_cls(in_channels, inner_dim, kernel_size=1, stride=1, padding=0)
-        elif self.is_input_vectorized:
-            assert sample_size is not None, "Transformer2DModel over discrete input must provide sample_size"
-            assert num_vector_embeds is not None, "Transformer2DModel over discrete input must provide num_embed"
-
-            self.height = sample_size
-            self.width = sample_size
-            self.num_vector_embeds = num_vector_embeds
-            self.num_latent_pixels = self.height * self.width
-
-            self.latent_image_embedding = ImagePositionalEmbeddings(
-                num_embed=num_vector_embeds, embed_dim=inner_dim, height=self.height, width=self.width
-            )
-        elif self.is_input_patches:
-            assert sample_size is not None, "Transformer2DModel over patched input must provide sample_size"
-
-            self.height = sample_size
-            self.width = sample_size
-
-            self.patch_size = patch_size
-            interpolation_scale = self.config.sample_size // 64  # => 64 (= 512 pixart) has interpolation scale 1
-            interpolation_scale = max(interpolation_scale, 1)
-            self.pos_embed = PatchEmbed(
-                height=sample_size,
-                width=sample_size,
-                patch_size=patch_size,
-                in_channels=in_channels,
-                embed_dim=inner_dim,
-                interpolation_scale=interpolation_scale,
-            )
-
-        # 3. Define transformers blocks
-        self.transformer_blocks = nn.ModuleList(
-            [
-                BasicTransformerBlock(
-                    inner_dim,
-                    num_attention_heads,
-                    attention_head_dim,
-                    dropout=dropout,
-                    cross_attention_dim=cross_attention_dim,
-                    activation_fn=activation_fn,
-                    num_embeds_ada_norm=num_embeds_ada_norm,
-                    attention_bias=attention_bias,
-                    only_cross_attention=only_cross_attention,
-                    double_self_attention=double_self_attention,
-                    upcast_attention=upcast_attention,
-                    norm_type=norm_type,
-                    norm_elementwise_affine=norm_elementwise_affine,
-                    norm_eps=norm_eps,
-                    attention_type=attention_type,
-                )
-                for d in range(num_layers)
-            ]
-        )
-
-        # 4. Define output layers
-        self.out_channels = in_channels if out_channels is None else out_channels
-        if self.is_input_continuous:
-            # TODO: should use out_channels for continuous projections
-            if use_linear_projection:
-                self.proj_out = linear_cls(inner_dim, in_channels)
-            else:
-                self.proj_out = conv_cls(inner_dim, in_channels, kernel_size=1, stride=1, padding=0)
-        elif self.is_input_vectorized:
-            self.norm_out = nn.LayerNorm(inner_dim)
-            self.out = nn.Linear(inner_dim, self.num_vector_embeds - 1)
-        elif self.is_input_patches and norm_type != "ada_norm_single":
-            self.norm_out = nn.LayerNorm(inner_dim, elementwise_affine=False, eps=1e-6)
-            self.proj_out_1 = nn.Linear(inner_dim, 2 * inner_dim)
-            self.proj_out_2 = nn.Linear(inner_dim, patch_size * patch_size * self.out_channels)
-        elif self.is_input_patches and norm_type == "ada_norm_single":
-            self.norm_out = nn.LayerNorm(inner_dim, elementwise_affine=False, eps=1e-6)
-            self.scale_shift_table = nn.Parameter(torch.randn(2, inner_dim) / inner_dim**0.5)
-            self.proj_out = nn.Linear(inner_dim, patch_size * patch_size * self.out_channels)
-
-        # 5. PixArt-Alpha blocks.
-        self.adaln_single = None
-        self.use_additional_conditions = False
-        if norm_type == "ada_norm_single":
-            self.use_additional_conditions = self.config.sample_size == 128
-            # TODO(Sayak, PVP) clean this, for now we use sample size to determine whether to use
-            # additional conditions until we find better name
-            self.adaln_single = AdaLayerNormSingle(inner_dim, use_additional_conditions=self.use_additional_conditions)
-
-        self.caption_projection = None
-        if caption_channels is not None:
-            self.caption_projection = PixArtAlphaTextProjection(in_features=caption_channels, hidden_size=inner_dim)
-
-        self.gradient_checkpointing = False
-
-    def _set_gradient_checkpointing(self, module, value=False):
-        if hasattr(module, "gradient_checkpointing"):
-            module.gradient_checkpointing = value
-
-    def forward(
-        self,
-        hidden_states: torch.Tensor,
-        encoder_hidden_states: Optional[torch.Tensor] = None,
-        timestep: Optional[torch.LongTensor] = None,
-        added_cond_kwargs: Dict[str, torch.Tensor] = None,
-        class_labels: Optional[torch.LongTensor] = None,
-        cross_attention_kwargs: Dict[str, Any] = None,
-        attention_mask: Optional[torch.Tensor] = None,
-        encoder_attention_mask: Optional[torch.Tensor] = None,
-        return_dict: bool = True,
-    ):
-        """
-        The [`Transformer2DModel`] forward method.
-
-        Args:
-            hidden_states (`torch.LongTensor` of shape `(batch size, num latent pixels)` if discrete, `torch.FloatTensor` of shape `(batch size, channel, height, width)` if continuous):
-                Input `hidden_states`.
-            encoder_hidden_states ( `torch.FloatTensor` of shape `(batch size, sequence len, embed dims)`, *optional*):
-                Conditional embeddings for cross attention layer. If not given, cross-attention defaults to
-                self-attention.
-            timestep ( `torch.LongTensor`, *optional*):
-                Used to indicate denoising step. Optional timestep to be applied as an embedding in `AdaLayerNorm`.
-            class_labels ( `torch.LongTensor` of shape `(batch size, num classes)`, *optional*):
-                Used to indicate class labels conditioning. Optional class labels to be applied as an embedding in
-                `AdaLayerZeroNorm`.
-            cross_attention_kwargs ( `Dict[str, Any]`, *optional*):
-                A kwargs dictionary that if specified is passed along to the `AttentionProcessor` as defined under
-                `self.processor` in
-                [diffusers.models.attention_processor](https://github.com/huggingface/diffusers/blob/main/src/diffusers/models/attention_processor.py).
-            attention_mask ( `torch.Tensor`, *optional*):
-                An attention mask of shape `(batch, key_tokens)` is applied to `encoder_hidden_states`. If `1` the mask
-                is kept, otherwise if `0` it is discarded. Mask will be converted into a bias, which adds large
-                negative values to the attention scores corresponding to "discard" tokens.
-            encoder_attention_mask ( `torch.Tensor`, *optional*):
-                Cross-attention mask applied to `encoder_hidden_states`. Two formats supported:
-
-                    * Mask `(batch, sequence_length)` True = keep, False = discard.
-                    * Bias `(batch, 1, sequence_length)` 0 = keep, -10000 = discard.
-
-                If `ndim == 2`: will be interpreted as a mask, then converted into a bias consistent with the format
-                above. This bias will be added to the cross-attention scores.
-            return_dict (`bool`, *optional*, defaults to `True`):
-                Whether or not to return a [`~models.unets.unet_2d_condition.UNet2DConditionOutput`] instead of a plain
-                tuple.
-
-        Returns:
-            If `return_dict` is True, an [`~models.transformer_2d.Transformer2DModelOutput`] is returned, otherwise a
-            `tuple` where the first element is the sample tensor.
-        """
-        # ensure attention_mask is a bias, and give it a singleton query_tokens dimension.
-        #   we may have done this conversion already, e.g. if we came here via UNet2DConditionModel#forward.
-        #   we can tell by counting dims; if ndim == 2: it's a mask rather than a bias.
-        # expects mask of shape:
-        #   [batch, key_tokens]
-        # adds singleton query_tokens dimension:
-        #   [batch,                    1, key_tokens]
-        # this helps to broadcast it as a bias over attention scores, which will be in one of the following shapes:
-        #   [batch,  heads, query_tokens, key_tokens] (e.g. torch sdp attn)
-        #   [batch * heads, query_tokens, key_tokens] (e.g. xformers or classic attn)
-        if attention_mask is not None and attention_mask.ndim == 2:
-            # assume that mask is expressed as:
-            #   (1 = keep,      0 = discard)
-            # convert mask into a bias that can be added to attention scores:
-            #       (keep = +0,     discard = -10000.0)
-            attention_mask = (1 - attention_mask.to(hidden_states.dtype)) * -10000.0
-            attention_mask = attention_mask.unsqueeze(1)
-
-        # convert encoder_attention_mask to a bias the same way we do for attention_mask
-        if encoder_attention_mask is not None and encoder_attention_mask.ndim == 2:
-            encoder_attention_mask = (1 - encoder_attention_mask.to(hidden_states.dtype)) * -10000.0
-            encoder_attention_mask = encoder_attention_mask.unsqueeze(1)
-
-        # Retrieve lora scale.
-        lora_scale = cross_attention_kwargs.get("scale", 1.0) if cross_attention_kwargs is not None else 1.0
-
-        # 1. Input
-        if self.is_input_continuous:
-            batch, _, height, width = hidden_states.shape
-            residual = hidden_states
-
-            hidden_states = self.norm(hidden_states)
-            if not self.use_linear_projection:
-                hidden_states = (
-                    self.proj_in(hidden_states, scale=lora_scale)
-                    if not USE_PEFT_BACKEND
-                    else self.proj_in(hidden_states)
-                )
-                inner_dim = hidden_states.shape[1]
-                hidden_states = hidden_states.permute(0, 2, 3, 1).reshape(batch, height * width, inner_dim)
-            else:
-                inner_dim = hidden_states.shape[1]
-                hidden_states = hidden_states.permute(0, 2, 3, 1).reshape(batch, height * width, inner_dim)
-                hidden_states = (
-                    self.proj_in(hidden_states, scale=lora_scale)
-                    if not USE_PEFT_BACKEND
-                    else self.proj_in(hidden_states)
-                )
-
-        elif self.is_input_vectorized:
-            hidden_states = self.latent_image_embedding(hidden_states)
-        elif self.is_input_patches:
-            height, width = hidden_states.shape[-2] // self.patch_size, hidden_states.shape[-1] // self.patch_size
-            hidden_states = self.pos_embed(hidden_states)
-
-            if self.adaln_single is not None:
-                if self.use_additional_conditions and added_cond_kwargs is None:
-                    raise ValueError(
-                        "`added_cond_kwargs` cannot be None when using additional conditions for `adaln_single`."
-                    )
-                batch_size = hidden_states.shape[0]
-                timestep, embedded_timestep = self.adaln_single(
-                    timestep, added_cond_kwargs, batch_size=batch_size, hidden_dtype=hidden_states.dtype
-                )
-
-        # 2. Blocks
-        if self.caption_projection is not None:
-            batch_size = hidden_states.shape[0]
-            encoder_hidden_states = self.caption_projection(encoder_hidden_states)
-            encoder_hidden_states = encoder_hidden_states.view(batch_size, -1, hidden_states.shape[-1])
-
-        for block in self.transformer_blocks:
-            if self.training and self.gradient_checkpointing:
-
-                def create_custom_forward(module, return_dict=None):
-                    def custom_forward(*inputs):
-                        if return_dict is not None:
-                            return module(*inputs, return_dict=return_dict)
-                        else:
-                            return module(*inputs)
-
-                    return custom_forward
-
-                ckpt_kwargs: Dict[str, Any] = {"use_reentrant": False} if is_torch_version(">=", "1.11.0") else {}
-                hidden_states = torch.utils.checkpoint.checkpoint(
-                    create_custom_forward(block),
-                    hidden_states,
-                    attention_mask,
-                    encoder_hidden_states,
-                    encoder_attention_mask,
-                    timestep,
-                    cross_attention_kwargs,
-                    class_labels,
-                    **ckpt_kwargs,
-                )
-            else:
-                hidden_states = block(
-                    hidden_states,
-                    attention_mask=attention_mask,
-                    encoder_hidden_states=encoder_hidden_states,
-                    encoder_attention_mask=encoder_attention_mask,
-                    timestep=timestep,
-                    cross_attention_kwargs=cross_attention_kwargs,
-                    class_labels=class_labels,
-                )
-
-        # 3. Output
-        if self.is_input_continuous:
-            if not self.use_linear_projection:
-                hidden_states = hidden_states.reshape(batch, height, width, inner_dim).permute(0, 3, 1, 2).contiguous()
-                hidden_states = (
-                    self.proj_out(hidden_states, scale=lora_scale)
-                    if not USE_PEFT_BACKEND
-                    else self.proj_out(hidden_states)
-                )
-            else:
-                hidden_states = (
-                    self.proj_out(hidden_states, scale=lora_scale)
-                    if not USE_PEFT_BACKEND
-                    else self.proj_out(hidden_states)
-                )
-                hidden_states = hidden_states.reshape(batch, height, width, inner_dim).permute(0, 3, 1, 2).contiguous()
-
-            output = hidden_states + residual
-        elif self.is_input_vectorized:
-            hidden_states = self.norm_out(hidden_states)
-            logits = self.out(hidden_states)
-            # (batch, self.num_vector_embeds - 1, self.num_latent_pixels)
-            logits = logits.permute(0, 2, 1)
-
-            # log(p(x_0))
-            output = F.log_softmax(logits.double(), dim=1).float()
-
-        if self.is_input_patches:
-            if self.config.norm_type != "ada_norm_single":
-                conditioning = self.transformer_blocks[0].norm1.emb(
-                    timestep, class_labels, hidden_dtype=hidden_states.dtype
-                )
-                shift, scale = self.proj_out_1(F.silu(conditioning)).chunk(2, dim=1)
-                hidden_states = self.norm_out(hidden_states) * (1 + scale[:, None]) + shift[:, None]
-                hidden_states = self.proj_out_2(hidden_states)
-            elif self.config.norm_type == "ada_norm_single":
-                shift, scale = (self.scale_shift_table[None] + embedded_timestep[:, None]).chunk(2, dim=1)
-                hidden_states = self.norm_out(hidden_states)
-                # Modulation
-                hidden_states = hidden_states * (1 + scale) + shift
-                hidden_states = self.proj_out(hidden_states)
-                hidden_states = hidden_states.squeeze(1)
-
-            # unpatchify
-            if self.adaln_single is None:
-                height = width = int(hidden_states.shape[1] ** 0.5)
-            hidden_states = hidden_states.reshape(
-                shape=(-1, height, width, self.patch_size, self.patch_size, self.out_channels)
-            )
-            hidden_states = torch.einsum("nhwpqc->nchpwq", hidden_states)
-            output = hidden_states.reshape(
-                shape=(-1, self.out_channels, height * self.patch_size, width * self.patch_size)
-            )
-
-        if not return_dict:
-            return (output,)
-
-        return Transformer2DModelOutput(sample=output)
+class Transformer2DModel(Transformer2DModel):
+    deprecation_message = "Importing `Transformer2DModel` from `diffusers.models.transformer_2d` is deprecated and this will be removed in a future version. Please use `from diffusers.models.transformers.transformer_2d import Transformer2DModel`, instead."
+    deprecate("Transformer2DModel", "0.29", deprecation_message)

src/diffusers/models/transformer_temporal.py

@@ -11,369 +11,24 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-from dataclasses import dataclass
-from typing import Any, Dict, Optional
+from ..utils import deprecate
+from .transformers.transformer_temporal import (
+    TransformerSpatioTemporalModel,
+    TransformerTemporalModel,
+    TransformerTemporalModelOutput,
+)
 
-import torch
-from torch import nn
 
-from ..configuration_utils import ConfigMixin, register_to_config
-from ..utils import BaseOutput
-from .attention import BasicTransformerBlock, TemporalBasicTransformerBlock
-from .embeddings import TimestepEmbedding, Timesteps
-from .modeling_utils import ModelMixin
-from .resnet import AlphaBlender
+class TransformerTemporalModelOutput(TransformerTemporalModelOutput):
+    deprecation_message = "Importing `TransformerTemporalModelOutput` from `diffusers.models.transformer_temporal` is deprecated and this will be removed in a future version. Please use `from diffusers.models.transformers.tranformer_temporal import TransformerTemporalModelOutput`, instead."
+    deprecate("TransformerTemporalModelOutput", "0.29", deprecation_message)
 
 
-@dataclass
-class TransformerTemporalModelOutput(BaseOutput):
-    """
-    The output of [`TransformerTemporalModel`].
+class TransformerTemporalModel(TransformerTemporalModel):
+    deprecation_message = "Importing `TransformerTemporalModel` from `diffusers.models.transformer_temporal` is deprecated and this will be removed in a future version. Please use `from diffusers.models.transformers.tranformer_temporal import TransformerTemporalModel`, instead."
+    deprecate("TransformerTemporalModel", "0.29", deprecation_message)
 
-    Args:
-        sample (`torch.FloatTensor` of shape `(batch_size x num_frames, num_channels, height, width)`):
-            The hidden states output conditioned on `encoder_hidden_states` input.
-    """
 
-    sample: torch.FloatTensor
-
-
-class TransformerTemporalModel(ModelMixin, ConfigMixin):
-    """
-    A Transformer model for video-like data.
-
-    Parameters:
-        num_attention_heads (`int`, *optional*, defaults to 16): The number of heads to use for multi-head attention.
-        attention_head_dim (`int`, *optional*, defaults to 88): The number of channels in each head.
-        in_channels (`int`, *optional*):
-            The number of channels in the input and output (specify if the input is **continuous**).
-        num_layers (`int`, *optional*, defaults to 1): The number of layers of Transformer blocks to use.
-        dropout (`float`, *optional*, defaults to 0.0): The dropout probability to use.
-        cross_attention_dim (`int`, *optional*): The number of `encoder_hidden_states` dimensions to use.
-        attention_bias (`bool`, *optional*):
-            Configure if the `TransformerBlock` attention should contain a bias parameter.
-        sample_size (`int`, *optional*): The width of the latent images (specify if the input is **discrete**).
-            This is fixed during training since it is used to learn a number of position embeddings.
-        activation_fn (`str`, *optional*, defaults to `"geglu"`):
-            Activation function to use in feed-forward. See `diffusers.models.activations.get_activation` for supported
-            activation functions.
-        norm_elementwise_affine (`bool`, *optional*):
-            Configure if the `TransformerBlock` should use learnable elementwise affine parameters for normalization.
-        double_self_attention (`bool`, *optional*):
-            Configure if each `TransformerBlock` should contain two self-attention layers.
-        positional_embeddings: (`str`, *optional*):
-            The type of positional embeddings to apply to the sequence input before passing use.
-        num_positional_embeddings: (`int`, *optional*):
-            The maximum length of the sequence over which to apply positional embeddings.
-    """
-
-    @register_to_config
-    def __init__(
-        self,
-        num_attention_heads: int = 16,
-        attention_head_dim: int = 88,
-        in_channels: Optional[int] = None,
-        out_channels: Optional[int] = None,
-        num_layers: int = 1,
-        dropout: float = 0.0,
-        norm_num_groups: int = 32,
-        cross_attention_dim: Optional[int] = None,
-        attention_bias: bool = False,
-        sample_size: Optional[int] = None,
-        activation_fn: str = "geglu",
-        norm_elementwise_affine: bool = True,
-        double_self_attention: bool = True,
-        positional_embeddings: Optional[str] = None,
-        num_positional_embeddings: Optional[int] = None,
-    ):
-        super().__init__()
-        self.num_attention_heads = num_attention_heads
-        self.attention_head_dim = attention_head_dim
-        inner_dim = num_attention_heads * attention_head_dim
-
-        self.in_channels = in_channels
-
-        self.norm = torch.nn.GroupNorm(num_groups=norm_num_groups, num_channels=in_channels, eps=1e-6, affine=True)
-        self.proj_in = nn.Linear(in_channels, inner_dim)
-
-        # 3. Define transformers blocks
-        self.transformer_blocks = nn.ModuleList(
-            [
-                BasicTransformerBlock(
-                    inner_dim,
-                    num_attention_heads,
-                    attention_head_dim,
-                    dropout=dropout,
-                    cross_attention_dim=cross_attention_dim,
-                    activation_fn=activation_fn,
-                    attention_bias=attention_bias,
-                    double_self_attention=double_self_attention,
-                    norm_elementwise_affine=norm_elementwise_affine,
-                    positional_embeddings=positional_embeddings,
-                    num_positional_embeddings=num_positional_embeddings,
-                )
-                for d in range(num_layers)
-            ]
-        )
-
-        self.proj_out = nn.Linear(inner_dim, in_channels)
-
-    def forward(
-        self,
-        hidden_states: torch.FloatTensor,
-        encoder_hidden_states: Optional[torch.LongTensor] = None,
-        timestep: Optional[torch.LongTensor] = None,
-        class_labels: torch.LongTensor = None,
-        num_frames: int = 1,
-        cross_attention_kwargs: Optional[Dict[str, Any]] = None,
-        return_dict: bool = True,
-    ) -> TransformerTemporalModelOutput:
-        """
-        The [`TransformerTemporal`] forward method.
-
-        Args:
-            hidden_states (`torch.LongTensor` of shape `(batch size, num latent pixels)` if discrete, `torch.FloatTensor` of shape `(batch size, channel, height, width)` if continuous):
-                Input hidden_states.
-            encoder_hidden_states ( `torch.LongTensor` of shape `(batch size, encoder_hidden_states dim)`, *optional*):
-                Conditional embeddings for cross attention layer. If not given, cross-attention defaults to
-                self-attention.
-            timestep ( `torch.LongTensor`, *optional*):
-                Used to indicate denoising step. Optional timestep to be applied as an embedding in `AdaLayerNorm`.
-            class_labels ( `torch.LongTensor` of shape `(batch size, num classes)`, *optional*):
-                Used to indicate class labels conditioning. Optional class labels to be applied as an embedding in
-                `AdaLayerZeroNorm`.
-            num_frames (`int`, *optional*, defaults to 1):
-                The number of frames to be processed per batch. This is used to reshape the hidden states.
-            cross_attention_kwargs (`dict`, *optional*):
-                A kwargs dictionary that if specified is passed along to the `AttentionProcessor` as defined under
-                `self.processor` in
-                [diffusers.models.attention_processor](https://github.com/huggingface/diffusers/blob/main/src/diffusers/models/attention_processor.py).
-            return_dict (`bool`, *optional*, defaults to `True`):
-                Whether or not to return a [`~models.unets.unet_2d_condition.UNet2DConditionOutput`] instead of a plain
-                tuple.
-
-        Returns:
-            [`~models.transformer_temporal.TransformerTemporalModelOutput`] or `tuple`:
-                If `return_dict` is True, an [`~models.transformer_temporal.TransformerTemporalModelOutput`] is
-                returned, otherwise a `tuple` where the first element is the sample tensor.
-        """
-        # 1. Input
-        batch_frames, channel, height, width = hidden_states.shape
-        batch_size = batch_frames // num_frames
-
-        residual = hidden_states
-
-        hidden_states = hidden_states[None, :].reshape(batch_size, num_frames, channel, height, width)
-        hidden_states = hidden_states.permute(0, 2, 1, 3, 4)
-
-        hidden_states = self.norm(hidden_states)
-        hidden_states = hidden_states.permute(0, 3, 4, 2, 1).reshape(batch_size * height * width, num_frames, channel)
-
-        hidden_states = self.proj_in(hidden_states)
-
-        # 2. Blocks
-        for block in self.transformer_blocks:
-            hidden_states = block(
-                hidden_states,
-                encoder_hidden_states=encoder_hidden_states,
-                timestep=timestep,
-                cross_attention_kwargs=cross_attention_kwargs,
-                class_labels=class_labels,
-            )
-
-        # 3. Output
-        hidden_states = self.proj_out(hidden_states)
-        hidden_states = (
-            hidden_states[None, None, :]
-            .reshape(batch_size, height, width, num_frames, channel)
-            .permute(0, 3, 4, 1, 2)
-            .contiguous()
-        )
-        hidden_states = hidden_states.reshape(batch_frames, channel, height, width)
-
-        output = hidden_states + residual
-
-        if not return_dict:
-            return (output,)
-
-        return TransformerTemporalModelOutput(sample=output)
-
-
-class TransformerSpatioTemporalModel(nn.Module):
-    """
-    A Transformer model for video-like data.
-
-    Parameters:
-        num_attention_heads (`int`, *optional*, defaults to 16): The number of heads to use for multi-head attention.
-        attention_head_dim (`int`, *optional*, defaults to 88): The number of channels in each head.
-        in_channels (`int`, *optional*):
-            The number of channels in the input and output (specify if the input is **continuous**).
-        out_channels (`int`, *optional*):
-            The number of channels in the output (specify if the input is **continuous**).
-        num_layers (`int`, *optional*, defaults to 1): The number of layers of Transformer blocks to use.
-        cross_attention_dim (`int`, *optional*): The number of `encoder_hidden_states` dimensions to use.
-    """
-
-    def __init__(
-        self,
-        num_attention_heads: int = 16,
-        attention_head_dim: int = 88,
-        in_channels: int = 320,
-        out_channels: Optional[int] = None,
-        num_layers: int = 1,
-        cross_attention_dim: Optional[int] = None,
-    ):
-        super().__init__()
-        self.num_attention_heads = num_attention_heads
-        self.attention_head_dim = attention_head_dim
-
-        inner_dim = num_attention_heads * attention_head_dim
-        self.inner_dim = inner_dim
-
-        # 2. Define input layers
-        self.in_channels = in_channels
-        self.norm = torch.nn.GroupNorm(num_groups=32, num_channels=in_channels, eps=1e-6)
-        self.proj_in = nn.Linear(in_channels, inner_dim)
-
-        # 3. Define transformers blocks
-        self.transformer_blocks = nn.ModuleList(
-            [
-                BasicTransformerBlock(
-                    inner_dim,
-                    num_attention_heads,
-                    attention_head_dim,
-                    cross_attention_dim=cross_attention_dim,
-                )
-                for d in range(num_layers)
-            ]
-        )
-
-        time_mix_inner_dim = inner_dim
-        self.temporal_transformer_blocks = nn.ModuleList(
-            [
-                TemporalBasicTransformerBlock(
-                    inner_dim,
-                    time_mix_inner_dim,
-                    num_attention_heads,
-                    attention_head_dim,
-                    cross_attention_dim=cross_attention_dim,
-                )
-                for _ in range(num_layers)
-            ]
-        )
-
-        time_embed_dim = in_channels * 4
-        self.time_pos_embed = TimestepEmbedding(in_channels, time_embed_dim, out_dim=in_channels)
-        self.time_proj = Timesteps(in_channels, True, 0)
-        self.time_mixer = AlphaBlender(alpha=0.5, merge_strategy="learned_with_images")
-
-        # 4. Define output layers
-        self.out_channels = in_channels if out_channels is None else out_channels
-        # TODO: should use out_channels for continuous projections
-        self.proj_out = nn.Linear(inner_dim, in_channels)
-
-        self.gradient_checkpointing = False
-
-    def forward(
-        self,
-        hidden_states: torch.Tensor,
-        encoder_hidden_states: Optional[torch.Tensor] = None,
-        image_only_indicator: Optional[torch.Tensor] = None,
-        return_dict: bool = True,
-    ):
-        """
-        Args:
-            hidden_states (`torch.FloatTensor` of shape `(batch size, channel, height, width)`):
-                Input hidden_states.
-            num_frames (`int`):
-                The number of frames to be processed per batch. This is used to reshape the hidden states.
-            encoder_hidden_states ( `torch.LongTensor` of shape `(batch size, encoder_hidden_states dim)`, *optional*):
-                Conditional embeddings for cross attention layer. If not given, cross-attention defaults to
-                self-attention.
-            image_only_indicator (`torch.LongTensor` of shape `(batch size, num_frames)`, *optional*):
-                A tensor indicating whether the input contains only images. 1 indicates that the input contains only
-                images, 0 indicates that the input contains video frames.
-            return_dict (`bool`, *optional*, defaults to `True`):
-                Whether or not to return a [`~models.transformer_temporal.TransformerTemporalModelOutput`] instead of a plain
-                tuple.
-
-        Returns:
-            [`~models.transformer_temporal.TransformerTemporalModelOutput`] or `tuple`:
-                If `return_dict` is True, an [`~models.transformer_temporal.TransformerTemporalModelOutput`] is
-                returned, otherwise a `tuple` where the first element is the sample tensor.
-        """
-        # 1. Input
-        batch_frames, _, height, width = hidden_states.shape
-        num_frames = image_only_indicator.shape[-1]
-        batch_size = batch_frames // num_frames
-
-        time_context = encoder_hidden_states
-        time_context_first_timestep = time_context[None, :].reshape(
-            batch_size, num_frames, -1, time_context.shape[-1]
-        )[:, 0]
-        time_context = time_context_first_timestep[None, :].broadcast_to(
-            height * width, batch_size, 1, time_context.shape[-1]
-        )
-        time_context = time_context.reshape(height * width * batch_size, 1, time_context.shape[-1])
-
-        residual = hidden_states
-
-        hidden_states = self.norm(hidden_states)
-        inner_dim = hidden_states.shape[1]
-        hidden_states = hidden_states.permute(0, 2, 3, 1).reshape(batch_frames, height * width, inner_dim)
-        hidden_states = self.proj_in(hidden_states)
-
-        num_frames_emb = torch.arange(num_frames, device=hidden_states.device)
-        num_frames_emb = num_frames_emb.repeat(batch_size, 1)
-        num_frames_emb = num_frames_emb.reshape(-1)
-        t_emb = self.time_proj(num_frames_emb)
-
-        # `Timesteps` does not contain any weights and will always return f32 tensors
-        # but time_embedding might actually be running in fp16. so we need to cast here.
-        # there might be better ways to encapsulate this.
-        t_emb = t_emb.to(dtype=hidden_states.dtype)
-
-        emb = self.time_pos_embed(t_emb)
-        emb = emb[:, None, :]
-
-        # 2. Blocks
-        for block, temporal_block in zip(self.transformer_blocks, self.temporal_transformer_blocks):
-            if self.training and self.gradient_checkpointing:
-                hidden_states = torch.utils.checkpoint.checkpoint(
-                    block,
-                    hidden_states,
-                    None,
-                    encoder_hidden_states,
-                    None,
-                    use_reentrant=False,
-                )
-            else:
-                hidden_states = block(
-                    hidden_states,
-                    encoder_hidden_states=encoder_hidden_states,
-                )
-
-            hidden_states_mix = hidden_states
-            hidden_states_mix = hidden_states_mix + emb
-
-            hidden_states_mix = temporal_block(
-                hidden_states_mix,
-                num_frames=num_frames,
-                encoder_hidden_states=time_context,
-            )
-            hidden_states = self.time_mixer(
-                x_spatial=hidden_states,
-                x_temporal=hidden_states_mix,
-                image_only_indicator=image_only_indicator,
-            )
-
-        # 3. Output
-        hidden_states = self.proj_out(hidden_states)
-        hidden_states = hidden_states.reshape(batch_frames, height, width, inner_dim).permute(0, 3, 1, 2).contiguous()
-
-        output = hidden_states + residual
-
-        if not return_dict:
-            return (output,)
-
-        return TransformerTemporalModelOutput(sample=output)
+class TransformerSpatioTemporalModel(TransformerSpatioTemporalModel):
+    deprecation_message = "Importing `TransformerSpatioTemporalModel` from `diffusers.models.transformer_temporal` is deprecated and this will be removed in a future version. Please use `from diffusers.models.transformers.tranformer_temporal import TransformerSpatioTemporalModel`, instead."
+    deprecate("TransformerTemporalModelOutput", "0.29", deprecation_message)

src/diffusers/models/transformers/__init__.py

+from ...utils import is_torch_available
+
+
+if is_torch_available():
+    from .dual_transformer_2d import DualTransformer2DModel
+    from .prior_transformer import PriorTransformer
+    from .t5_film_transformer import T5FilmDecoder
+    from .transformer_2d import Transformer2DModel
+    from .transformer_temporal import TransformerTemporalModel

src/diffusers/models/transformers/dual_transformer_2d.py

+# Copyright 2023 The HuggingFace Team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+from typing import Optional
+
+from torch import nn
+
+from .transformer_2d import Transformer2DModel, Transformer2DModelOutput
+
+
+class DualTransformer2DModel(nn.Module):
+    """
+    Dual transformer wrapper that combines two `Transformer2DModel`s for mixed inference.
+
+    Parameters:
+        num_attention_heads (`int`, *optional*, defaults to 16): The number of heads to use for multi-head attention.
+        attention_head_dim (`int`, *optional*, defaults to 88): The number of channels in each head.
+        in_channels (`int`, *optional*):
+            Pass if the input is continuous. The number of channels in the input and output.
+        num_layers (`int`, *optional*, defaults to 1): The number of layers of Transformer blocks to use.
+        dropout (`float`, *optional*, defaults to 0.1): The dropout probability to use.
+        cross_attention_dim (`int`, *optional*): The number of encoder_hidden_states dimensions to use.
+        sample_size (`int`, *optional*): Pass if the input is discrete. The width of the latent images.
+            Note that this is fixed at training time as it is used for learning a number of position embeddings. See
+            `ImagePositionalEmbeddings`.
+        num_vector_embeds (`int`, *optional*):
+            Pass if the input is discrete. The number of classes of the vector embeddings of the latent pixels.
+            Includes the class for the masked latent pixel.
+        activation_fn (`str`, *optional*, defaults to `"geglu"`): Activation function to be used in feed-forward.
+        num_embeds_ada_norm ( `int`, *optional*): Pass if at least one of the norm_layers is `AdaLayerNorm`.
+            The number of diffusion steps used during training. Note that this is fixed at training time as it is used
+            to learn a number of embeddings that are added to the hidden states. During inference, you can denoise for
+            up to but not more than steps than `num_embeds_ada_norm`.
+        attention_bias (`bool`, *optional*):
+            Configure if the TransformerBlocks' attention should contain a bias parameter.
+    """
+
+    def __init__(
+        self,
+        num_attention_heads: int = 16,
+        attention_head_dim: int = 88,
+        in_channels: Optional[int] = None,
+        num_layers: int = 1,
+        dropout: float = 0.0,
+        norm_num_groups: int = 32,
+        cross_attention_dim: Optional[int] = None,
+        attention_bias: bool = False,
+        sample_size: Optional[int] = None,
+        num_vector_embeds: Optional[int] = None,
+        activation_fn: str = "geglu",
+        num_embeds_ada_norm: Optional[int] = None,
+    ):
+        super().__init__()
+        self.transformers = nn.ModuleList(
+            [
+                Transformer2DModel(
+                    num_attention_heads=num_attention_heads,
+                    attention_head_dim=attention_head_dim,
+                    in_channels=in_channels,
+                    num_layers=num_layers,
+                    dropout=dropout,
+                    norm_num_groups=norm_num_groups,
+                    cross_attention_dim=cross_attention_dim,
+                    attention_bias=attention_bias,
+                    sample_size=sample_size,
+                    num_vector_embeds=num_vector_embeds,
+                    activation_fn=activation_fn,
+                    num_embeds_ada_norm=num_embeds_ada_norm,
+                )
+                for _ in range(2)
+            ]
+        )
+
+        # Variables that can be set by a pipeline:
+
+        # The ratio of transformer1 to transformer2's output states to be combined during inference
+        self.mix_ratio = 0.5
+
+        # The shape of `encoder_hidden_states` is expected to be
+        # `(batch_size, condition_lengths[0]+condition_lengths[1], num_features)`
+        self.condition_lengths = [77, 257]
+
+        # Which transformer to use to encode which condition.
+        # E.g. `(1, 0)` means that we'll use `transformers[1](conditions[0])` and `transformers[0](conditions[1])`
+        self.transformer_index_for_condition = [1, 0]
+
+    def forward(
+        self,
+        hidden_states,
+        encoder_hidden_states,
+        timestep=None,
+        attention_mask=None,
+        cross_attention_kwargs=None,
+        return_dict: bool = True,
+    ):
+        """
+        Args:
+            hidden_states ( When discrete, `torch.LongTensor` of shape `(batch size, num latent pixels)`.
+                When continuous, `torch.FloatTensor` of shape `(batch size, channel, height, width)`): Input
+                hidden_states.
+            encoder_hidden_states ( `torch.LongTensor` of shape `(batch size, encoder_hidden_states dim)`, *optional*):
+                Conditional embeddings for cross attention layer. If not given, cross-attention defaults to
+                self-attention.
+            timestep ( `torch.long`, *optional*):
+                Optional timestep to be applied as an embedding in AdaLayerNorm's. Used to indicate denoising step.
+            attention_mask (`torch.FloatTensor`, *optional*):
+                Optional attention mask to be applied in Attention.
+            cross_attention_kwargs (`dict`, *optional*):
+                A kwargs dictionary that if specified is passed along to the `AttentionProcessor` as defined under
+                `self.processor` in
+                [diffusers.models.attention_processor](https://github.com/huggingface/diffusers/blob/main/src/diffusers/models/attention_processor.py).
+            return_dict (`bool`, *optional*, defaults to `True`):
+                Whether or not to return a [`models.unets.unet_2d_condition.UNet2DConditionOutput`] instead of a plain tuple.
+
+        Returns:
+            [`~models.transformer_2d.Transformer2DModelOutput`] or `tuple`:
+            [`~models.transformer_2d.Transformer2DModelOutput`] if `return_dict` is True, otherwise a `tuple`. When
+            returning a tuple, the first element is the sample tensor.
+        """
+        input_states = hidden_states
+
+        encoded_states = []
+        tokens_start = 0
+        # attention_mask is not used yet
+        for i in range(2):
+            # for each of the two transformers, pass the corresponding condition tokens
+            condition_state = encoder_hidden_states[:, tokens_start : tokens_start + self.condition_lengths[i]]
+            transformer_index = self.transformer_index_for_condition[i]
+            encoded_state = self.transformers[transformer_index](
+                input_states,
+                encoder_hidden_states=condition_state,
+                timestep=timestep,
+                cross_attention_kwargs=cross_attention_kwargs,
+                return_dict=False,
+            )[0]
+            encoded_states.append(encoded_state - input_states)
+            tokens_start += self.condition_lengths[i]
+
+        output_states = encoded_states[0] * self.mix_ratio + encoded_states[1] * (1 - self.mix_ratio)
+        output_states = output_states + input_states
+
+        if not return_dict:
+            return (output_states,)
+
+        return Transformer2DModelOutput(sample=output_states)

src/diffusers/models/transformers/prior_transformer.py

+from dataclasses import dataclass
+from typing import Dict, Optional, Union
+
+import torch
+import torch.nn.functional as F
+from torch import nn
+
+from ...configuration_utils import ConfigMixin, register_to_config
+from ...loaders import PeftAdapterMixin, UNet2DConditionLoadersMixin
+from ...utils import BaseOutput
+from ..attention import BasicTransformerBlock
+from ..attention_processor import (
+    ADDED_KV_ATTENTION_PROCESSORS,
+    CROSS_ATTENTION_PROCESSORS,
+    AttentionProcessor,
+    AttnAddedKVProcessor,
+    AttnProcessor,
+)
+from ..embeddings import TimestepEmbedding, Timesteps
+from ..modeling_utils import ModelMixin
+
+
+@dataclass
+class PriorTransformerOutput(BaseOutput):
+    """
+    The output of [`PriorTransformer`].
+
+    Args:
+        predicted_image_embedding (`torch.FloatTensor` of shape `(batch_size, embedding_dim)`):
+            The predicted CLIP image embedding conditioned on the CLIP text embedding input.
+    """
+
+    predicted_image_embedding: torch.FloatTensor
+
+
+class PriorTransformer(ModelMixin, ConfigMixin, UNet2DConditionLoadersMixin, PeftAdapterMixin):
+    """
+    A Prior Transformer model.
+
+    Parameters:
+        num_attention_heads (`int`, *optional*, defaults to 32): The number of heads to use for multi-head attention.
+        attention_head_dim (`int`, *optional*, defaults to 64): The number of channels in each head.
+        num_layers (`int`, *optional*, defaults to 20): The number of layers of Transformer blocks to use.
+        embedding_dim (`int`, *optional*, defaults to 768): The dimension of the model input `hidden_states`
+        num_embeddings (`int`, *optional*, defaults to 77):
+            The number of embeddings of the model input `hidden_states`
+        additional_embeddings (`int`, *optional*, defaults to 4): The number of additional tokens appended to the
+            projected `hidden_states`. The actual length of the used `hidden_states` is `num_embeddings +
+            additional_embeddings`.
+        dropout (`float`, *optional*, defaults to 0.0): The dropout probability to use.
+        time_embed_act_fn (`str`, *optional*, defaults to 'silu'):
+            The activation function to use to create timestep embeddings.
+        norm_in_type (`str`, *optional*, defaults to None): The normalization layer to apply on hidden states before
+            passing to Transformer blocks. Set it to `None` if normalization is not needed.
+        embedding_proj_norm_type (`str`, *optional*, defaults to None):
+            The normalization layer to apply on the input `proj_embedding`. Set it to `None` if normalization is not
+            needed.
+        encoder_hid_proj_type (`str`, *optional*, defaults to `linear`):
+            The projection layer to apply on the input `encoder_hidden_states`. Set it to `None` if
+            `encoder_hidden_states` is `None`.
+        added_emb_type (`str`, *optional*, defaults to `prd`): Additional embeddings to condition the model.
+            Choose from `prd` or `None`. if choose `prd`, it will prepend a token indicating the (quantized) dot
+            product between the text embedding and image embedding as proposed in the unclip paper
+            https://arxiv.org/abs/2204.06125 If it is `None`, no additional embeddings will be prepended.
+        time_embed_dim (`int, *optional*, defaults to None): The dimension of timestep embeddings.
+            If None, will be set to `num_attention_heads * attention_head_dim`
+        embedding_proj_dim (`int`, *optional*, default to None):
+            The dimension of `proj_embedding`. If None, will be set to `embedding_dim`.
+        clip_embed_dim (`int`, *optional*, default to None):
+            The dimension of the output. If None, will be set to `embedding_dim`.
+    """
+
+    @register_to_config
+    def __init__(
+        self,
+        num_attention_heads: int = 32,
+        attention_head_dim: int = 64,
+        num_layers: int = 20,
+        embedding_dim: int = 768,
+        num_embeddings=77,
+        additional_embeddings=4,
+        dropout: float = 0.0,
+        time_embed_act_fn: str = "silu",
+        norm_in_type: Optional[str] = None,  # layer
+        embedding_proj_norm_type: Optional[str] = None,  # layer
+        encoder_hid_proj_type: Optional[str] = "linear",  # linear
+        added_emb_type: Optional[str] = "prd",  # prd
+        time_embed_dim: Optional[int] = None,
+        embedding_proj_dim: Optional[int] = None,
+        clip_embed_dim: Optional[int] = None,
+    ):
+        super().__init__()
+        self.num_attention_heads = num_attention_heads
+        self.attention_head_dim = attention_head_dim
+        inner_dim = num_attention_heads * attention_head_dim
+        self.additional_embeddings = additional_embeddings
+
+        time_embed_dim = time_embed_dim or inner_dim
+        embedding_proj_dim = embedding_proj_dim or embedding_dim
+        clip_embed_dim = clip_embed_dim or embedding_dim
+
+        self.time_proj = Timesteps(inner_dim, True, 0)
+        self.time_embedding = TimestepEmbedding(inner_dim, time_embed_dim, out_dim=inner_dim, act_fn=time_embed_act_fn)
+
+        self.proj_in = nn.Linear(embedding_dim, inner_dim)
+
+        if embedding_proj_norm_type is None:
+            self.embedding_proj_norm = None
+        elif embedding_proj_norm_type == "layer":
+            self.embedding_proj_norm = nn.LayerNorm(embedding_proj_dim)
+        else:
+            raise ValueError(f"unsupported embedding_proj_norm_type: {embedding_proj_norm_type}")
+
+        self.embedding_proj = nn.Linear(embedding_proj_dim, inner_dim)
+
+        if encoder_hid_proj_type is None:
+            self.encoder_hidden_states_proj = None
+        elif encoder_hid_proj_type == "linear":
+            self.encoder_hidden_states_proj = nn.Linear(embedding_dim, inner_dim)
+        else:
+            raise ValueError(f"unsupported encoder_hid_proj_type: {encoder_hid_proj_type}")
+
+        self.positional_embedding = nn.Parameter(torch.zeros(1, num_embeddings + additional_embeddings, inner_dim))
+
+        if added_emb_type == "prd":
+            self.prd_embedding = nn.Parameter(torch.zeros(1, 1, inner_dim))
+        elif added_emb_type is None:
+            self.prd_embedding = None
+        else:
+            raise ValueError(
+                f"`added_emb_type`: {added_emb_type} is not supported. Make sure to choose one of `'prd'` or `None`."
+            )
+
+        self.transformer_blocks = nn.ModuleList(
+            [
+                BasicTransformerBlock(
+                    inner_dim,
+                    num_attention_heads,
+                    attention_head_dim,
+                    dropout=dropout,
+                    activation_fn="gelu",
+                    attention_bias=True,
+                )
+                for d in range(num_layers)
+            ]
+        )
+
+        if norm_in_type == "layer":
+            self.norm_in = nn.LayerNorm(inner_dim)
+        elif norm_in_type is None:
+            self.norm_in = None
+        else:
+            raise ValueError(f"Unsupported norm_in_type: {norm_in_type}.")
+
+        self.norm_out = nn.LayerNorm(inner_dim)
+
+        self.proj_to_clip_embeddings = nn.Linear(inner_dim, clip_embed_dim)
+
+        causal_attention_mask = torch.full(
+            [num_embeddings + additional_embeddings, num_embeddings + additional_embeddings], -10000.0
+        )
+        causal_attention_mask.triu_(1)
+        causal_attention_mask = causal_attention_mask[None, ...]
+        self.register_buffer("causal_attention_mask", causal_attention_mask, persistent=False)
+
+        self.clip_mean = nn.Parameter(torch.zeros(1, clip_embed_dim))
+        self.clip_std = nn.Parameter(torch.zeros(1, clip_embed_dim))
+
+    @property
+    # Copied from diffusers.models.unets.unet_2d_condition.UNet2DConditionModel.attn_processors
+    def attn_processors(self) -> Dict[str, AttentionProcessor]:
+        r"""
+        Returns:
+            `dict` of attention processors: A dictionary containing all attention processors used in the model with
+            indexed by its weight name.
+        """
+        # set recursively
+        processors = {}
+
+        def fn_recursive_add_processors(name: str, module: torch.nn.Module, processors: Dict[str, AttentionProcessor]):
+            if hasattr(module, "get_processor"):
+                processors[f"{name}.processor"] = module.get_processor(return_deprecated_lora=True)
+
+            for sub_name, child in module.named_children():
+                fn_recursive_add_processors(f"{name}.{sub_name}", child, processors)
+
+            return processors
+
+        for name, module in self.named_children():
+            fn_recursive_add_processors(name, module, processors)
+
+        return processors
+
+    # Copied from diffusers.models.unets.unet_2d_condition.UNet2DConditionModel.set_attn_processor
+    def set_attn_processor(self, processor: Union[AttentionProcessor, Dict[str, AttentionProcessor]]):
+        r"""
+        Sets the attention processor to use to compute attention.
+
+        Parameters:
+            processor (`dict` of `AttentionProcessor` or only `AttentionProcessor`):
+                The instantiated processor class or a dictionary of processor classes that will be set as the processor
+                for **all** `Attention` layers.
+
+                If `processor` is a dict, the key needs to define the path to the corresponding cross attention
+                processor. This is strongly recommended when setting trainable attention processors.
+
+        """
+        count = len(self.attn_processors.keys())
+
+        if isinstance(processor, dict) and len(processor) != count:
+            raise ValueError(
+                f"A dict of processors was passed, but the number of processors {len(processor)} does not match the"
+                f" number of attention layers: {count}. Please make sure to pass {count} processor classes."
+            )
+
+        def fn_recursive_attn_processor(name: str, module: torch.nn.Module, processor):
+            if hasattr(module, "set_processor"):
+                if not isinstance(processor, dict):
+                    module.set_processor(processor)
+                else:
+                    module.set_processor(processor.pop(f"{name}.processor"))
+
+            for sub_name, child in module.named_children():
+                fn_recursive_attn_processor(f"{name}.{sub_name}", child, processor)
+
+        for name, module in self.named_children():
+            fn_recursive_attn_processor(name, module, processor)
+
+    # Copied from diffusers.models.unets.unet_2d_condition.UNet2DConditionModel.set_default_attn_processor
+    def set_default_attn_processor(self):
+        """
+        Disables custom attention processors and sets the default attention implementation.
+        """
+        if all(proc.__class__ in ADDED_KV_ATTENTION_PROCESSORS for proc in self.attn_processors.values()):
+            processor = AttnAddedKVProcessor()
+        elif all(proc.__class__ in CROSS_ATTENTION_PROCESSORS for proc in self.attn_processors.values()):
+            processor = AttnProcessor()
+        else:
+            raise ValueError(
+                f"Cannot call `set_default_attn_processor` when attention processors are of type {next(iter(self.attn_processors.values()))}"
+            )
+
+        self.set_attn_processor(processor)
+
+    def forward(
+        self,
+        hidden_states,
+        timestep: Union[torch.Tensor, float, int],
+        proj_embedding: torch.FloatTensor,
+        encoder_hidden_states: Optional[torch.FloatTensor] = None,
+        attention_mask: Optional[torch.BoolTensor] = None,
+        return_dict: bool = True,
+    ):
+        """
+        The [`PriorTransformer`] forward method.
+
+        Args:
+            hidden_states (`torch.FloatTensor` of shape `(batch_size, embedding_dim)`):
+                The currently predicted image embeddings.
+            timestep (`torch.LongTensor`):
+                Current denoising step.
+            proj_embedding (`torch.FloatTensor` of shape `(batch_size, embedding_dim)`):
+                Projected embedding vector the denoising process is conditioned on.
+            encoder_hidden_states (`torch.FloatTensor` of shape `(batch_size, num_embeddings, embedding_dim)`):
+                Hidden states of the text embeddings the denoising process is conditioned on.
+            attention_mask (`torch.BoolTensor` of shape `(batch_size, num_embeddings)`):
+                Text mask for the text embeddings.
+            return_dict (`bool`, *optional*, defaults to `True`):
+                Whether or not to return a [`~models.prior_transformer.PriorTransformerOutput`] instead of a plain
+                tuple.
+
+        Returns:
+            [`~models.prior_transformer.PriorTransformerOutput`] or `tuple`:
+                If return_dict is True, a [`~models.prior_transformer.PriorTransformerOutput`] is returned, otherwise a
+                tuple is returned where the first element is the sample tensor.
+        """
+        batch_size = hidden_states.shape[0]
+
+        timesteps = timestep
+        if not torch.is_tensor(timesteps):
+            timesteps = torch.tensor([timesteps], dtype=torch.long, device=hidden_states.device)
+        elif torch.is_tensor(timesteps) and len(timesteps.shape) == 0:
+            timesteps = timesteps[None].to(hidden_states.device)
+
+        # broadcast to batch dimension in a way that's compatible with ONNX/Core ML
+        timesteps = timesteps * torch.ones(batch_size, dtype=timesteps.dtype, device=timesteps.device)
+
+        timesteps_projected = self.time_proj(timesteps)
+
+        # timesteps does not contain any weights and will always return f32 tensors
+        # but time_embedding might be fp16, so we need to cast here.
+        timesteps_projected = timesteps_projected.to(dtype=self.dtype)
+        time_embeddings = self.time_embedding(timesteps_projected)
+
+        if self.embedding_proj_norm is not None:
+            proj_embedding = self.embedding_proj_norm(proj_embedding)
+
+        proj_embeddings = self.embedding_proj(proj_embedding)
+        if self.encoder_hidden_states_proj is not None and encoder_hidden_states is not None:
+            encoder_hidden_states = self.encoder_hidden_states_proj(encoder_hidden_states)
+        elif self.encoder_hidden_states_proj is not None and encoder_hidden_states is None:
+            raise ValueError("`encoder_hidden_states_proj` requires `encoder_hidden_states` to be set")
+
+        hidden_states = self.proj_in(hidden_states)
+
+        positional_embeddings = self.positional_embedding.to(hidden_states.dtype)
+
+        additional_embeds = []
+        additional_embeddings_len = 0
+
+        if encoder_hidden_states is not None:
+            additional_embeds.append(encoder_hidden_states)
+            additional_embeddings_len += encoder_hidden_states.shape[1]
+
+        if len(proj_embeddings.shape) == 2:
+            proj_embeddings = proj_embeddings[:, None, :]
+
+        if len(hidden_states.shape) == 2:
+            hidden_states = hidden_states[:, None, :]
+
+        additional_embeds = additional_embeds + [
+            proj_embeddings,
+            time_embeddings[:, None, :],
+            hidden_states,
+        ]
+
+        if self.prd_embedding is not None:
+            prd_embedding = self.prd_embedding.to(hidden_states.dtype).expand(batch_size, -1, -1)
+            additional_embeds.append(prd_embedding)
+
+        hidden_states = torch.cat(
+            additional_embeds,
+            dim=1,
+        )
+
+        # Allow positional_embedding to not include the `addtional_embeddings` and instead pad it with zeros for these additional tokens
+        additional_embeddings_len = additional_embeddings_len + proj_embeddings.shape[1] + 1
+        if positional_embeddings.shape[1] < hidden_states.shape[1]:
+            positional_embeddings = F.pad(
+                positional_embeddings,
+                (
+                    0,
+                    0,
+                    additional_embeddings_len,
+                    self.prd_embedding.shape[1] if self.prd_embedding is not None else 0,
+                ),
+                value=0.0,
+            )
+
+        hidden_states = hidden_states + positional_embeddings
+
+        if attention_mask is not None:
+            attention_mask = (1 - attention_mask.to(hidden_states.dtype)) * -10000.0
+            attention_mask = F.pad(attention_mask, (0, self.additional_embeddings), value=0.0)
+            attention_mask = (attention_mask[:, None, :] + self.causal_attention_mask).to(hidden_states.dtype)
+            attention_mask = attention_mask.repeat_interleave(self.config.num_attention_heads, dim=0)
+
+        if self.norm_in is not None:
+            hidden_states = self.norm_in(hidden_states)
+
+        for block in self.transformer_blocks:
+            hidden_states = block(hidden_states, attention_mask=attention_mask)
+
+        hidden_states = self.norm_out(hidden_states)
+
+        if self.prd_embedding is not None:
+            hidden_states = hidden_states[:, -1]
+        else:
+            hidden_states = hidden_states[:, additional_embeddings_len:]
+
+        predicted_image_embedding = self.proj_to_clip_embeddings(hidden_states)
+
+        if not return_dict:
+            return (predicted_image_embedding,)
+
+        return PriorTransformerOutput(predicted_image_embedding=predicted_image_embedding)
+
+    def post_process_latents(self, prior_latents):
+        prior_latents = (prior_latents * self.clip_std) + self.clip_mean
+        return prior_latents

src/diffusers/models/transformers/t5_film_transformer.py

+# Copyright 2023 The HuggingFace Team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import math
+from typing import Optional, Tuple
+
+import torch
+from torch import nn
+
+from ...configuration_utils import ConfigMixin, register_to_config
+from ..attention_processor import Attention
+from ..embeddings import get_timestep_embedding
+from ..modeling_utils import ModelMixin
+
+
+class T5FilmDecoder(ModelMixin, ConfigMixin):
+    r"""
+    T5 style decoder with FiLM conditioning.
+
+    Args:
+        input_dims (`int`, *optional*, defaults to `128`):
+            The number of input dimensions.
+        targets_length (`int`, *optional*, defaults to `256`):
+            The length of the targets.
+        d_model (`int`, *optional*, defaults to `768`):
+            Size of the input hidden states.
+        num_layers (`int`, *optional*, defaults to `12`):
+            The number of `DecoderLayer`'s to use.
+        num_heads (`int`, *optional*, defaults to `12`):
+            The number of attention heads to use.
+        d_kv (`int`, *optional*, defaults to `64`):
+            Size of the key-value projection vectors.
+        d_ff (`int`, *optional*, defaults to `2048`):
+            The number of dimensions in the intermediate feed-forward layer of `DecoderLayer`'s.
+        dropout_rate (`float`, *optional*, defaults to `0.1`):
+            Dropout probability.
+    """
+
+    @register_to_config
+    def __init__(
+        self,
+        input_dims: int = 128,
+        targets_length: int = 256,
+        max_decoder_noise_time: float = 2000.0,
+        d_model: int = 768,
+        num_layers: int = 12,
+        num_heads: int = 12,
+        d_kv: int = 64,
+        d_ff: int = 2048,
+        dropout_rate: float = 0.1,
+    ):
+        super().__init__()
+
+        self.conditioning_emb = nn.Sequential(
+            nn.Linear(d_model, d_model * 4, bias=False),
+            nn.SiLU(),
+            nn.Linear(d_model * 4, d_model * 4, bias=False),
+            nn.SiLU(),
+        )
+
+        self.position_encoding = nn.Embedding(targets_length, d_model)
+        self.position_encoding.weight.requires_grad = False
+
+        self.continuous_inputs_projection = nn.Linear(input_dims, d_model, bias=False)
+
+        self.dropout = nn.Dropout(p=dropout_rate)
+
+        self.decoders = nn.ModuleList()
+        for lyr_num in range(num_layers):
+            # FiLM conditional T5 decoder
+            lyr = DecoderLayer(d_model=d_model, d_kv=d_kv, num_heads=num_heads, d_ff=d_ff, dropout_rate=dropout_rate)
+            self.decoders.append(lyr)
+
+        self.decoder_norm = T5LayerNorm(d_model)
+
+        self.post_dropout = nn.Dropout(p=dropout_rate)
+        self.spec_out = nn.Linear(d_model, input_dims, bias=False)
+
+    def encoder_decoder_mask(self, query_input: torch.FloatTensor, key_input: torch.FloatTensor) -> torch.FloatTensor:
+        mask = torch.mul(query_input.unsqueeze(-1), key_input.unsqueeze(-2))
+        return mask.unsqueeze(-3)
+
+    def forward(self, encodings_and_masks, decoder_input_tokens, decoder_noise_time):
+        batch, _, _ = decoder_input_tokens.shape
+        assert decoder_noise_time.shape == (batch,)
+
+        # decoder_noise_time is in [0, 1), so rescale to expected timing range.
+        time_steps = get_timestep_embedding(
+            decoder_noise_time * self.config.max_decoder_noise_time,
+            embedding_dim=self.config.d_model,
+            max_period=self.config.max_decoder_noise_time,
+        ).to(dtype=self.dtype)
+
+        conditioning_emb = self.conditioning_emb(time_steps).unsqueeze(1)
+
+        assert conditioning_emb.shape == (batch, 1, self.config.d_model * 4)
+
+        seq_length = decoder_input_tokens.shape[1]
+
+        # If we want to use relative positions for audio context, we can just offset
+        # this sequence by the length of encodings_and_masks.
+        decoder_positions = torch.broadcast_to(
+            torch.arange(seq_length, device=decoder_input_tokens.device),
+            (batch, seq_length),
+        )
+
+        position_encodings = self.position_encoding(decoder_positions)
+
+        inputs = self.continuous_inputs_projection(decoder_input_tokens)
+        inputs += position_encodings
+        y = self.dropout(inputs)
+
+        # decoder: No padding present.
+        decoder_mask = torch.ones(
+            decoder_input_tokens.shape[:2], device=decoder_input_tokens.device, dtype=inputs.dtype
+        )
+
+        # Translate encoding masks to encoder-decoder masks.
+        encodings_and_encdec_masks = [(x, self.encoder_decoder_mask(decoder_mask, y)) for x, y in encodings_and_masks]
+
+        # cross attend style: concat encodings
+        encoded = torch.cat([x[0] for x in encodings_and_encdec_masks], dim=1)
+        encoder_decoder_mask = torch.cat([x[1] for x in encodings_and_encdec_masks], dim=-1)
+
+        for lyr in self.decoders:
+            y = lyr(
+                y,
+                conditioning_emb=conditioning_emb,
+                encoder_hidden_states=encoded,
+                encoder_attention_mask=encoder_decoder_mask,
+            )[0]
+
+        y = self.decoder_norm(y)
+        y = self.post_dropout(y)
+
+        spec_out = self.spec_out(y)
+        return spec_out
+
+
+class DecoderLayer(nn.Module):
+    r"""
+    T5 decoder layer.
+
+    Args:
+        d_model (`int`):
+            Size of the input hidden states.
+        d_kv (`int`):
+            Size of the key-value projection vectors.
+        num_heads (`int`):
+            Number of attention heads.
+        d_ff (`int`):
+            Size of the intermediate feed-forward layer.
+        dropout_rate (`float`):
+            Dropout probability.
+        layer_norm_epsilon (`float`, *optional*, defaults to `1e-6`):
+            A small value used for numerical stability to avoid dividing by zero.
+    """
+
+    def __init__(
+        self, d_model: int, d_kv: int, num_heads: int, d_ff: int, dropout_rate: float, layer_norm_epsilon: float = 1e-6
+    ):
+        super().__init__()
+        self.layer = nn.ModuleList()
+
+        # cond self attention: layer 0
+        self.layer.append(
+            T5LayerSelfAttentionCond(d_model=d_model, d_kv=d_kv, num_heads=num_heads, dropout_rate=dropout_rate)
+        )
+
+        # cross attention: layer 1
+        self.layer.append(
+            T5LayerCrossAttention(
+                d_model=d_model,
+                d_kv=d_kv,
+                num_heads=num_heads,
+                dropout_rate=dropout_rate,
+                layer_norm_epsilon=layer_norm_epsilon,
+            )
+        )
+
+        # Film Cond MLP + dropout: last layer
+        self.layer.append(
+            T5LayerFFCond(d_model=d_model, d_ff=d_ff, dropout_rate=dropout_rate, layer_norm_epsilon=layer_norm_epsilon)
+        )
+
+    def forward(
+        self,
+        hidden_states: torch.FloatTensor,
+        conditioning_emb: Optional[torch.FloatTensor] = None,
+        attention_mask: Optional[torch.FloatTensor] = None,
+        encoder_hidden_states: Optional[torch.Tensor] = None,
+        encoder_attention_mask: Optional[torch.Tensor] = None,
+        encoder_decoder_position_bias=None,
+    ) -> Tuple[torch.FloatTensor]:
+        hidden_states = self.layer[0](
+            hidden_states,
+            conditioning_emb=conditioning_emb,
+            attention_mask=attention_mask,
+        )
+
+        if encoder_hidden_states is not None:
+            encoder_extended_attention_mask = torch.where(encoder_attention_mask > 0, 0, -1e10).to(
+                encoder_hidden_states.dtype
+            )
+
+            hidden_states = self.layer[1](
+                hidden_states,
+                key_value_states=encoder_hidden_states,
+                attention_mask=encoder_extended_attention_mask,
+            )
+
+        # Apply Film Conditional Feed Forward layer
+        hidden_states = self.layer[-1](hidden_states, conditioning_emb)
+
+        return (hidden_states,)
+
+
+class T5LayerSelfAttentionCond(nn.Module):
+    r"""
+    T5 style self-attention layer with conditioning.
+
+    Args:
+        d_model (`int`):
+            Size of the input hidden states.
+        d_kv (`int`):
+            Size of the key-value projection vectors.
+        num_heads (`int`):
+            Number of attention heads.
+        dropout_rate (`float`):
+            Dropout probability.
+    """
+
+    def __init__(self, d_model: int, d_kv: int, num_heads: int, dropout_rate: float):
+        super().__init__()
+        self.layer_norm = T5LayerNorm(d_model)
+        self.FiLMLayer = T5FiLMLayer(in_features=d_model * 4, out_features=d_model)
+        self.attention = Attention(query_dim=d_model, heads=num_heads, dim_head=d_kv, out_bias=False, scale_qk=False)
+        self.dropout = nn.Dropout(dropout_rate)
+
+    def forward(
+        self,
+        hidden_states: torch.FloatTensor,
+        conditioning_emb: Optional[torch.FloatTensor] = None,
+        attention_mask: Optional[torch.FloatTensor] = None,
+    ) -> torch.FloatTensor:
+        # pre_self_attention_layer_norm
+        normed_hidden_states = self.layer_norm(hidden_states)
+
+        if conditioning_emb is not None:
+            normed_hidden_states = self.FiLMLayer(normed_hidden_states, conditioning_emb)
+
+        # Self-attention block
+        attention_output = self.attention(normed_hidden_states)
+
+        hidden_states = hidden_states + self.dropout(attention_output)
+
+        return hidden_states
+
+
+class T5LayerCrossAttention(nn.Module):
+    r"""
+    T5 style cross-attention layer.
+
+    Args:
+        d_model (`int`):
+            Size of the input hidden states.
+        d_kv (`int`):
+            Size of the key-value projection vectors.
+        num_heads (`int`):
+            Number of attention heads.
+        dropout_rate (`float`):
+            Dropout probability.
+        layer_norm_epsilon (`float`):
+            A small value used for numerical stability to avoid dividing by zero.
+    """
+
+    def __init__(self, d_model: int, d_kv: int, num_heads: int, dropout_rate: float, layer_norm_epsilon: float):
+        super().__init__()
+        self.attention = Attention(query_dim=d_model, heads=num_heads, dim_head=d_kv, out_bias=False, scale_qk=False)
+        self.layer_norm = T5LayerNorm(d_model, eps=layer_norm_epsilon)
+        self.dropout = nn.Dropout(dropout_rate)
+
+    def forward(
+        self,
+        hidden_states: torch.FloatTensor,
+        key_value_states: Optional[torch.FloatTensor] = None,
+        attention_mask: Optional[torch.FloatTensor] = None,
+    ) -> torch.FloatTensor:
+        normed_hidden_states = self.layer_norm(hidden_states)
+        attention_output = self.attention(
+            normed_hidden_states,
+            encoder_hidden_states=key_value_states,
+            attention_mask=attention_mask.squeeze(1),
+        )
+        layer_output = hidden_states + self.dropout(attention_output)
+        return layer_output
+
+
+class T5LayerFFCond(nn.Module):
+    r"""
+    T5 style feed-forward conditional layer.
+
+    Args:
+        d_model (`int`):
+            Size of the input hidden states.
+        d_ff (`int`):
+            Size of the intermediate feed-forward layer.
+        dropout_rate (`float`):
+            Dropout probability.
+        layer_norm_epsilon (`float`):
+            A small value used for numerical stability to avoid dividing by zero.
+    """
+
+    def __init__(self, d_model: int, d_ff: int, dropout_rate: float, layer_norm_epsilon: float):
+        super().__init__()
+        self.DenseReluDense = T5DenseGatedActDense(d_model=d_model, d_ff=d_ff, dropout_rate=dropout_rate)
+        self.film = T5FiLMLayer(in_features=d_model * 4, out_features=d_model)
+        self.layer_norm = T5LayerNorm(d_model, eps=layer_norm_epsilon)
+        self.dropout = nn.Dropout(dropout_rate)
+
+    def forward(
+        self, hidden_states: torch.FloatTensor, conditioning_emb: Optional[torch.FloatTensor] = None
+    ) -> torch.FloatTensor:
+        forwarded_states = self.layer_norm(hidden_states)
+        if conditioning_emb is not None:
+            forwarded_states = self.film(forwarded_states, conditioning_emb)
+
+        forwarded_states = self.DenseReluDense(forwarded_states)
+        hidden_states = hidden_states + self.dropout(forwarded_states)
+        return hidden_states
+
+
+class T5DenseGatedActDense(nn.Module):
+    r"""
+    T5 style feed-forward layer with gated activations and dropout.
+
+    Args:
+        d_model (`int`):
+            Size of the input hidden states.
+        d_ff (`int`):
+            Size of the intermediate feed-forward layer.
+        dropout_rate (`float`):
+            Dropout probability.
+    """
+
+    def __init__(self, d_model: int, d_ff: int, dropout_rate: float):
+        super().__init__()
+        self.wi_0 = nn.Linear(d_model, d_ff, bias=False)
+        self.wi_1 = nn.Linear(d_model, d_ff, bias=False)
+        self.wo = nn.Linear(d_ff, d_model, bias=False)
+        self.dropout = nn.Dropout(dropout_rate)
+        self.act = NewGELUActivation()
+
+    def forward(self, hidden_states: torch.FloatTensor) -> torch.FloatTensor:
+        hidden_gelu = self.act(self.wi_0(hidden_states))
+        hidden_linear = self.wi_1(hidden_states)
+        hidden_states = hidden_gelu * hidden_linear
+        hidden_states = self.dropout(hidden_states)
+
+        hidden_states = self.wo(hidden_states)
+        return hidden_states
+
+
+class T5LayerNorm(nn.Module):
+    r"""
+    T5 style layer normalization module.
+
+    Args:
+        hidden_size (`int`):
+            Size of the input hidden states.
+        eps (`float`, `optional`, defaults to `1e-6`):
+            A small value used for numerical stability to avoid dividing by zero.
+    """
+
+    def __init__(self, hidden_size: int, eps: float = 1e-6):
+        """
+        Construct a layernorm module in the T5 style. No bias and no subtraction of mean.
+        """
+        super().__init__()
+        self.weight = nn.Parameter(torch.ones(hidden_size))
+        self.variance_epsilon = eps
+
+    def forward(self, hidden_states: torch.FloatTensor) -> torch.FloatTensor:
+        # T5 uses a layer_norm which only scales and doesn't shift, which is also known as Root Mean
+        # Square Layer Normalization https://arxiv.org/abs/1910.07467 thus variance is calculated
+        # w/o mean and there is no bias. Additionally we want to make sure that the accumulation for
+        # half-precision inputs is done in fp32
+
+        variance = hidden_states.to(torch.float32).pow(2).mean(-1, keepdim=True)
+        hidden_states = hidden_states * torch.rsqrt(variance + self.variance_epsilon)
+
+        # convert into half-precision if necessary
+        if self.weight.dtype in [torch.float16, torch.bfloat16]:
+            hidden_states = hidden_states.to(self.weight.dtype)
+
+        return self.weight * hidden_states
+
+
+class NewGELUActivation(nn.Module):
+    """
+    Implementation of the GELU activation function currently in Google BERT repo (identical to OpenAI GPT). Also see
+    the Gaussian Error Linear Units paper: https://arxiv.org/abs/1606.08415
+    """
+
+    def forward(self, input: torch.Tensor) -> torch.Tensor:
+        return 0.5 * input * (1.0 + torch.tanh(math.sqrt(2.0 / math.pi) * (input + 0.044715 * torch.pow(input, 3.0))))
+
+
+class T5FiLMLayer(nn.Module):
+    """
+    T5 style FiLM Layer.
+
+    Args:
+        in_features (`int`):
+            Number of input features.
+        out_features (`int`):
+            Number of output features.
+    """
+
+    def __init__(self, in_features: int, out_features: int):
+        super().__init__()
+        self.scale_bias = nn.Linear(in_features, out_features * 2, bias=False)
+
+    def forward(self, x: torch.FloatTensor, conditioning_emb: torch.FloatTensor) -> torch.FloatTensor:
+        emb = self.scale_bias(conditioning_emb)
+        scale, shift = torch.chunk(emb, 2, -1)
+        x = x * (1 + scale) + shift
+        return x

src/diffusers/models/transformers/transformer_2d.py

+# Copyright 2023 The HuggingFace Team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+from dataclasses import dataclass
+from typing import Any, Dict, Optional
+
+import torch
+import torch.nn.functional as F
+from torch import nn
+
+from ...configuration_utils import ConfigMixin, register_to_config
+from ...utils import USE_PEFT_BACKEND, BaseOutput, deprecate, is_torch_version
+from ..attention import BasicTransformerBlock
+from ..embeddings import ImagePositionalEmbeddings, PatchEmbed, PixArtAlphaTextProjection
+from ..lora import LoRACompatibleConv, LoRACompatibleLinear
+from ..modeling_utils import ModelMixin
+from ..normalization import AdaLayerNormSingle
+
+
+@dataclass
+class Transformer2DModelOutput(BaseOutput):
+    """
+    The output of [`Transformer2DModel`].
+
+    Args:
+        sample (`torch.FloatTensor` of shape `(batch_size, num_channels, height, width)` or `(batch size, num_vector_embeds - 1, num_latent_pixels)` if [`Transformer2DModel`] is discrete):
+            The hidden states output conditioned on the `encoder_hidden_states` input. If discrete, returns probability
+            distributions for the unnoised latent pixels.
+    """
+
+    sample: torch.FloatTensor
+
+
+class Transformer2DModel(ModelMixin, ConfigMixin):
+    """
+    A 2D Transformer model for image-like data.
+
+    Parameters:
+        num_attention_heads (`int`, *optional*, defaults to 16): The number of heads to use for multi-head attention.
+        attention_head_dim (`int`, *optional*, defaults to 88): The number of channels in each head.
+        in_channels (`int`, *optional*):
+            The number of channels in the input and output (specify if the input is **continuous**).
+        num_layers (`int`, *optional*, defaults to 1): The number of layers of Transformer blocks to use.
+        dropout (`float`, *optional*, defaults to 0.0): The dropout probability to use.
+        cross_attention_dim (`int`, *optional*): The number of `encoder_hidden_states` dimensions to use.
+        sample_size (`int`, *optional*): The width of the latent images (specify if the input is **discrete**).
+            This is fixed during training since it is used to learn a number of position embeddings.
+        num_vector_embeds (`int`, *optional*):
+            The number of classes of the vector embeddings of the latent pixels (specify if the input is **discrete**).
+            Includes the class for the masked latent pixel.
+        activation_fn (`str`, *optional*, defaults to `"geglu"`): Activation function to use in feed-forward.
+        num_embeds_ada_norm ( `int`, *optional*):
+            The number of diffusion steps used during training. Pass if at least one of the norm_layers is
+            `AdaLayerNorm`. This is fixed during training since it is used to learn a number of embeddings that are
+            added to the hidden states.
+
+            During inference, you can denoise for up to but not more steps than `num_embeds_ada_norm`.
+        attention_bias (`bool`, *optional*):
+            Configure if the `TransformerBlocks` attention should contain a bias parameter.
+    """
+
+    _supports_gradient_checkpointing = True
+
+    @register_to_config
+    def __init__(
+        self,
+        num_attention_heads: int = 16,
+        attention_head_dim: int = 88,
+        in_channels: Optional[int] = None,
+        out_channels: Optional[int] = None,
+        num_layers: int = 1,
+        dropout: float = 0.0,
+        norm_num_groups: int = 32,
+        cross_attention_dim: Optional[int] = None,
+        attention_bias: bool = False,
+        sample_size: Optional[int] = None,
+        num_vector_embeds: Optional[int] = None,
+        patch_size: Optional[int] = None,
+        activation_fn: str = "geglu",
+        num_embeds_ada_norm: Optional[int] = None,
+        use_linear_projection: bool = False,
+        only_cross_attention: bool = False,
+        double_self_attention: bool = False,
+        upcast_attention: bool = False,
+        norm_type: str = "layer_norm",
+        norm_elementwise_affine: bool = True,
+        norm_eps: float = 1e-5,
+        attention_type: str = "default",
+        caption_channels: int = None,
+    ):
+        super().__init__()
+        self.use_linear_projection = use_linear_projection
+        self.num_attention_heads = num_attention_heads
+        self.attention_head_dim = attention_head_dim
+        inner_dim = num_attention_heads * attention_head_dim
+
+        conv_cls = nn.Conv2d if USE_PEFT_BACKEND else LoRACompatibleConv
+        linear_cls = nn.Linear if USE_PEFT_BACKEND else LoRACompatibleLinear
+
+        # 1. Transformer2DModel can process both standard continuous images of shape `(batch_size, num_channels, width, height)` as well as quantized image embeddings of shape `(batch_size, num_image_vectors)`
+        # Define whether input is continuous or discrete depending on configuration
+        self.is_input_continuous = (in_channels is not None) and (patch_size is None)
+        self.is_input_vectorized = num_vector_embeds is not None
+        self.is_input_patches = in_channels is not None and patch_size is not None
+
+        if norm_type == "layer_norm" and num_embeds_ada_norm is not None:
+            deprecation_message = (
+                f"The configuration file of this model: {self.__class__} is outdated. `norm_type` is either not set or"
+                " incorrectly set to `'layer_norm'`.Make sure to set `norm_type` to `'ada_norm'` in the config."
+                " Please make sure to update the config accordingly as leaving `norm_type` might led to incorrect"
+                " results in future versions. If you have downloaded this checkpoint from the Hugging Face Hub, it"
+                " would be very nice if you could open a Pull request for the `transformer/config.json` file"
+            )
+            deprecate("norm_type!=num_embeds_ada_norm", "1.0.0", deprecation_message, standard_warn=False)
+            norm_type = "ada_norm"
+
+        if self.is_input_continuous and self.is_input_vectorized:
+            raise ValueError(
+                f"Cannot define both `in_channels`: {in_channels} and `num_vector_embeds`: {num_vector_embeds}. Make"
+                " sure that either `in_channels` or `num_vector_embeds` is None."
+            )
+        elif self.is_input_vectorized and self.is_input_patches:
+            raise ValueError(
+                f"Cannot define both `num_vector_embeds`: {num_vector_embeds} and `patch_size`: {patch_size}. Make"
+                " sure that either `num_vector_embeds` or `num_patches` is None."
+            )
+        elif not self.is_input_continuous and not self.is_input_vectorized and not self.is_input_patches:
+            raise ValueError(
+                f"Has to define `in_channels`: {in_channels}, `num_vector_embeds`: {num_vector_embeds}, or patch_size:"
+                f" {patch_size}. Make sure that `in_channels`, `num_vector_embeds` or `num_patches` is not None."
+            )
+
+        # 2. Define input layers
+        if self.is_input_continuous:
+            self.in_channels = in_channels
+
+            self.norm = torch.nn.GroupNorm(num_groups=norm_num_groups, num_channels=in_channels, eps=1e-6, affine=True)
+            if use_linear_projection:
+                self.proj_in = linear_cls(in_channels, inner_dim)
+            else:
+                self.proj_in = conv_cls(in_channels, inner_dim, kernel_size=1, stride=1, padding=0)
+        elif self.is_input_vectorized:
+            assert sample_size is not None, "Transformer2DModel over discrete input must provide sample_size"
+            assert num_vector_embeds is not None, "Transformer2DModel over discrete input must provide num_embed"
+
+            self.height = sample_size
+            self.width = sample_size
+            self.num_vector_embeds = num_vector_embeds
+            self.num_latent_pixels = self.height * self.width
+
+            self.latent_image_embedding = ImagePositionalEmbeddings(
+                num_embed=num_vector_embeds, embed_dim=inner_dim, height=self.height, width=self.width
+            )
+        elif self.is_input_patches:
+            assert sample_size is not None, "Transformer2DModel over patched input must provide sample_size"
+
+            self.height = sample_size
+            self.width = sample_size
+
+            self.patch_size = patch_size
+            interpolation_scale = self.config.sample_size // 64  # => 64 (= 512 pixart) has interpolation scale 1
+            interpolation_scale = max(interpolation_scale, 1)
+            self.pos_embed = PatchEmbed(
+                height=sample_size,
+                width=sample_size,
+                patch_size=patch_size,
+                in_channels=in_channels,
+                embed_dim=inner_dim,
+                interpolation_scale=interpolation_scale,
+            )
+
+        # 3. Define transformers blocks
+        self.transformer_blocks = nn.ModuleList(
+            [
+                BasicTransformerBlock(
+                    inner_dim,
+                    num_attention_heads,
+                    attention_head_dim,
+                    dropout=dropout,
+                    cross_attention_dim=cross_attention_dim,
+                    activation_fn=activation_fn,
+                    num_embeds_ada_norm=num_embeds_ada_norm,
+                    attention_bias=attention_bias,
+                    only_cross_attention=only_cross_attention,
+                    double_self_attention=double_self_attention,
+                    upcast_attention=upcast_attention,
+                    norm_type=norm_type,
+                    norm_elementwise_affine=norm_elementwise_affine,
+                    norm_eps=norm_eps,
+                    attention_type=attention_type,
+                )
+                for d in range(num_layers)
+            ]
+        )
+
+        # 4. Define output layers
+        self.out_channels = in_channels if out_channels is None else out_channels
+        if self.is_input_continuous:
+            # TODO: should use out_channels for continuous projections
+            if use_linear_projection:
+                self.proj_out = linear_cls(inner_dim, in_channels)
+            else:
+                self.proj_out = conv_cls(inner_dim, in_channels, kernel_size=1, stride=1, padding=0)
+        elif self.is_input_vectorized:
+            self.norm_out = nn.LayerNorm(inner_dim)
+            self.out = nn.Linear(inner_dim, self.num_vector_embeds - 1)
+        elif self.is_input_patches and norm_type != "ada_norm_single":
+            self.norm_out = nn.LayerNorm(inner_dim, elementwise_affine=False, eps=1e-6)
+            self.proj_out_1 = nn.Linear(inner_dim, 2 * inner_dim)
+            self.proj_out_2 = nn.Linear(inner_dim, patch_size * patch_size * self.out_channels)
+        elif self.is_input_patches and norm_type == "ada_norm_single":
+            self.norm_out = nn.LayerNorm(inner_dim, elementwise_affine=False, eps=1e-6)
+            self.scale_shift_table = nn.Parameter(torch.randn(2, inner_dim) / inner_dim**0.5)
+            self.proj_out = nn.Linear(inner_dim, patch_size * patch_size * self.out_channels)
+
+        # 5. PixArt-Alpha blocks.
+        self.adaln_single = None
+        self.use_additional_conditions = False
+        if norm_type == "ada_norm_single":
+            self.use_additional_conditions = self.config.sample_size == 128
+            # TODO(Sayak, PVP) clean this, for now we use sample size to determine whether to use
+            # additional conditions until we find better name
+            self.adaln_single = AdaLayerNormSingle(inner_dim, use_additional_conditions=self.use_additional_conditions)
+
+        self.caption_projection = None
+        if caption_channels is not None:
+            self.caption_projection = PixArtAlphaTextProjection(in_features=caption_channels, hidden_size=inner_dim)
+
+        self.gradient_checkpointing = False
+
+    def _set_gradient_checkpointing(self, module, value=False):
+        if hasattr(module, "gradient_checkpointing"):
+            module.gradient_checkpointing = value
+
+    def forward(
+        self,
+        hidden_states: torch.Tensor,
+        encoder_hidden_states: Optional[torch.Tensor] = None,
+        timestep: Optional[torch.LongTensor] = None,
+        added_cond_kwargs: Dict[str, torch.Tensor] = None,
+        class_labels: Optional[torch.LongTensor] = None,
+        cross_attention_kwargs: Dict[str, Any] = None,
+        attention_mask: Optional[torch.Tensor] = None,
+        encoder_attention_mask: Optional[torch.Tensor] = None,
+        return_dict: bool = True,
+    ):
+        """
+        The [`Transformer2DModel`] forward method.
+
+        Args:
+            hidden_states (`torch.LongTensor` of shape `(batch size, num latent pixels)` if discrete, `torch.FloatTensor` of shape `(batch size, channel, height, width)` if continuous):
+                Input `hidden_states`.
+            encoder_hidden_states ( `torch.FloatTensor` of shape `(batch size, sequence len, embed dims)`, *optional*):
+                Conditional embeddings for cross attention layer. If not given, cross-attention defaults to
+                self-attention.
+            timestep ( `torch.LongTensor`, *optional*):
+                Used to indicate denoising step. Optional timestep to be applied as an embedding in `AdaLayerNorm`.
+            class_labels ( `torch.LongTensor` of shape `(batch size, num classes)`, *optional*):
+                Used to indicate class labels conditioning. Optional class labels to be applied as an embedding in
+                `AdaLayerZeroNorm`.
+            cross_attention_kwargs ( `Dict[str, Any]`, *optional*):
+                A kwargs dictionary that if specified is passed along to the `AttentionProcessor` as defined under
+                `self.processor` in
+                [diffusers.models.attention_processor](https://github.com/huggingface/diffusers/blob/main/src/diffusers/models/attention_processor.py).
+            attention_mask ( `torch.Tensor`, *optional*):
+                An attention mask of shape `(batch, key_tokens)` is applied to `encoder_hidden_states`. If `1` the mask
+                is kept, otherwise if `0` it is discarded. Mask will be converted into a bias, which adds large
+                negative values to the attention scores corresponding to "discard" tokens.
+            encoder_attention_mask ( `torch.Tensor`, *optional*):
+                Cross-attention mask applied to `encoder_hidden_states`. Two formats supported:
+
+                    * Mask `(batch, sequence_length)` True = keep, False = discard.
+                    * Bias `(batch, 1, sequence_length)` 0 = keep, -10000 = discard.
+
+                If `ndim == 2`: will be interpreted as a mask, then converted into a bias consistent with the format
+                above. This bias will be added to the cross-attention scores.
+            return_dict (`bool`, *optional*, defaults to `True`):
+                Whether or not to return a [`~models.unets.unet_2d_condition.UNet2DConditionOutput`] instead of a plain
+                tuple.
+
+        Returns:
+            If `return_dict` is True, an [`~models.transformer_2d.Transformer2DModelOutput`] is returned, otherwise a
+            `tuple` where the first element is the sample tensor.
+        """
+        # ensure attention_mask is a bias, and give it a singleton query_tokens dimension.
+        #   we may have done this conversion already, e.g. if we came here via UNet2DConditionModel#forward.
+        #   we can tell by counting dims; if ndim == 2: it's a mask rather than a bias.
+        # expects mask of shape:
+        #   [batch, key_tokens]
+        # adds singleton query_tokens dimension:
+        #   [batch,                    1, key_tokens]
+        # this helps to broadcast it as a bias over attention scores, which will be in one of the following shapes:
+        #   [batch,  heads, query_tokens, key_tokens] (e.g. torch sdp attn)
+        #   [batch * heads, query_tokens, key_tokens] (e.g. xformers or classic attn)
+        if attention_mask is not None and attention_mask.ndim == 2:
+            # assume that mask is expressed as:
+            #   (1 = keep,      0 = discard)
+            # convert mask into a bias that can be added to attention scores:
+            #       (keep = +0,     discard = -10000.0)
+            attention_mask = (1 - attention_mask.to(hidden_states.dtype)) * -10000.0
+            attention_mask = attention_mask.unsqueeze(1)
+
+        # convert encoder_attention_mask to a bias the same way we do for attention_mask
+        if encoder_attention_mask is not None and encoder_attention_mask.ndim == 2:
+            encoder_attention_mask = (1 - encoder_attention_mask.to(hidden_states.dtype)) * -10000.0
+            encoder_attention_mask = encoder_attention_mask.unsqueeze(1)
+
+        # Retrieve lora scale.
+        lora_scale = cross_attention_kwargs.get("scale", 1.0) if cross_attention_kwargs is not None else 1.0
+
+        # 1. Input
+        if self.is_input_continuous:
+            batch, _, height, width = hidden_states.shape
+            residual = hidden_states
+
+            hidden_states = self.norm(hidden_states)
+            if not self.use_linear_projection:
+                hidden_states = (
+                    self.proj_in(hidden_states, scale=lora_scale)
+                    if not USE_PEFT_BACKEND
+                    else self.proj_in(hidden_states)
+                )
+                inner_dim = hidden_states.shape[1]
+                hidden_states = hidden_states.permute(0, 2, 3, 1).reshape(batch, height * width, inner_dim)
+            else:
+                inner_dim = hidden_states.shape[1]
+                hidden_states = hidden_states.permute(0, 2, 3, 1).reshape(batch, height * width, inner_dim)
+                hidden_states = (
+                    self.proj_in(hidden_states, scale=lora_scale)
+                    if not USE_PEFT_BACKEND
+                    else self.proj_in(hidden_states)
+                )
+
+        elif self.is_input_vectorized:
+            hidden_states = self.latent_image_embedding(hidden_states)
+        elif self.is_input_patches:
+            height, width = hidden_states.shape[-2] // self.patch_size, hidden_states.shape[-1] // self.patch_size
+            hidden_states = self.pos_embed(hidden_states)
+
+            if self.adaln_single is not None:
+                if self.use_additional_conditions and added_cond_kwargs is None:
+                    raise ValueError(
+                        "`added_cond_kwargs` cannot be None when using additional conditions for `adaln_single`."
+                    )
+                batch_size = hidden_states.shape[0]
+                timestep, embedded_timestep = self.adaln_single(
+                    timestep, added_cond_kwargs, batch_size=batch_size, hidden_dtype=hidden_states.dtype
+                )
+
+        # 2. Blocks
+        if self.caption_projection is not None:
+            batch_size = hidden_states.shape[0]
+            encoder_hidden_states = self.caption_projection(encoder_hidden_states)
+            encoder_hidden_states = encoder_hidden_states.view(batch_size, -1, hidden_states.shape[-1])
+
+        for block in self.transformer_blocks:
+            if self.training and self.gradient_checkpointing:
+
+                def create_custom_forward(module, return_dict=None):
+                    def custom_forward(*inputs):
+                        if return_dict is not None:
+                            return module(*inputs, return_dict=return_dict)
+                        else:
+                            return module(*inputs)
+
+                    return custom_forward
+
+                ckpt_kwargs: Dict[str, Any] = {"use_reentrant": False} if is_torch_version(">=", "1.11.0") else {}
+                hidden_states = torch.utils.checkpoint.checkpoint(
+                    create_custom_forward(block),
+                    hidden_states,
+                    attention_mask,
+                    encoder_hidden_states,
+                    encoder_attention_mask,
+                    timestep,
+                    cross_attention_kwargs,
+                    class_labels,
+                    **ckpt_kwargs,
+                )
+            else:
+                hidden_states = block(
+                    hidden_states,
+                    attention_mask=attention_mask,
+                    encoder_hidden_states=encoder_hidden_states,
+                    encoder_attention_mask=encoder_attention_mask,
+                    timestep=timestep,
+                    cross_attention_kwargs=cross_attention_kwargs,
+                    class_labels=class_labels,
+                )
+
+        # 3. Output
+        if self.is_input_continuous:
+            if not self.use_linear_projection:
+                hidden_states = hidden_states.reshape(batch, height, width, inner_dim).permute(0, 3, 1, 2).contiguous()
+                hidden_states = (
+                    self.proj_out(hidden_states, scale=lora_scale)
+                    if not USE_PEFT_BACKEND
+                    else self.proj_out(hidden_states)
+                )
+            else:
+                hidden_states = (
+                    self.proj_out(hidden_states, scale=lora_scale)
+                    if not USE_PEFT_BACKEND
+                    else self.proj_out(hidden_states)
+                )
+                hidden_states = hidden_states.reshape(batch, height, width, inner_dim).permute(0, 3, 1, 2).contiguous()
+
+            output = hidden_states + residual
+        elif self.is_input_vectorized:
+            hidden_states = self.norm_out(hidden_states)
+            logits = self.out(hidden_states)
+            # (batch, self.num_vector_embeds - 1, self.num_latent_pixels)
+            logits = logits.permute(0, 2, 1)
+
+            # log(p(x_0))
+            output = F.log_softmax(logits.double(), dim=1).float()
+
+        if self.is_input_patches:
+            if self.config.norm_type != "ada_norm_single":
+                conditioning = self.transformer_blocks[0].norm1.emb(
+                    timestep, class_labels, hidden_dtype=hidden_states.dtype
+                )
+                shift, scale = self.proj_out_1(F.silu(conditioning)).chunk(2, dim=1)
+                hidden_states = self.norm_out(hidden_states) * (1 + scale[:, None]) + shift[:, None]
+                hidden_states = self.proj_out_2(hidden_states)
+            elif self.config.norm_type == "ada_norm_single":
+                shift, scale = (self.scale_shift_table[None] + embedded_timestep[:, None]).chunk(2, dim=1)
+                hidden_states = self.norm_out(hidden_states)
+                # Modulation
+                hidden_states = hidden_states * (1 + scale) + shift
+                hidden_states = self.proj_out(hidden_states)
+                hidden_states = hidden_states.squeeze(1)
+
+            # unpatchify
+            if self.adaln_single is None:
+                height = width = int(hidden_states.shape[1] ** 0.5)
+            hidden_states = hidden_states.reshape(
+                shape=(-1, height, width, self.patch_size, self.patch_size, self.out_channels)
+            )
+            hidden_states = torch.einsum("nhwpqc->nchpwq", hidden_states)
+            output = hidden_states.reshape(
+                shape=(-1, self.out_channels, height * self.patch_size, width * self.patch_size)
+            )
+
+        if not return_dict:
+            return (output,)
+
+        return Transformer2DModelOutput(sample=output)

src/diffusers/models/transformers/transformer_temporal.py

+# Copyright 2023 The HuggingFace Team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+from dataclasses import dataclass
+from typing import Any, Dict, Optional
+
+import torch
+from torch import nn
+
+from ...configuration_utils import ConfigMixin, register_to_config
+from ...utils import BaseOutput
+from ..attention import BasicTransformerBlock, TemporalBasicTransformerBlock
+from ..embeddings import TimestepEmbedding, Timesteps
+from ..modeling_utils import ModelMixin
+from ..resnet import AlphaBlender
+
+
+@dataclass
+class TransformerTemporalModelOutput(BaseOutput):
+    """
+    The output of [`TransformerTemporalModel`].
+
+    Args:
+        sample (`torch.FloatTensor` of shape `(batch_size x num_frames, num_channels, height, width)`):
+            The hidden states output conditioned on `encoder_hidden_states` input.
+    """
+
+    sample: torch.FloatTensor
+
+
+class TransformerTemporalModel(ModelMixin, ConfigMixin):
+    """
+    A Transformer model for video-like data.
+
+    Parameters:
+        num_attention_heads (`int`, *optional*, defaults to 16): The number of heads to use for multi-head attention.
+        attention_head_dim (`int`, *optional*, defaults to 88): The number of channels in each head.
+        in_channels (`int`, *optional*):
+            The number of channels in the input and output (specify if the input is **continuous**).
+        num_layers (`int`, *optional*, defaults to 1): The number of layers of Transformer blocks to use.
+        dropout (`float`, *optional*, defaults to 0.0): The dropout probability to use.
+        cross_attention_dim (`int`, *optional*): The number of `encoder_hidden_states` dimensions to use.
+        attention_bias (`bool`, *optional*):
+            Configure if the `TransformerBlock` attention should contain a bias parameter.
+        sample_size (`int`, *optional*): The width of the latent images (specify if the input is **discrete**).
+            This is fixed during training since it is used to learn a number of position embeddings.
+        activation_fn (`str`, *optional*, defaults to `"geglu"`):
+            Activation function to use in feed-forward. See `diffusers.models.activations.get_activation` for supported
+            activation functions.
+        norm_elementwise_affine (`bool`, *optional*):
+            Configure if the `TransformerBlock` should use learnable elementwise affine parameters for normalization.
+        double_self_attention (`bool`, *optional*):
+            Configure if each `TransformerBlock` should contain two self-attention layers.
+        positional_embeddings: (`str`, *optional*):
+            The type of positional embeddings to apply to the sequence input before passing use.
+        num_positional_embeddings: (`int`, *optional*):
+            The maximum length of the sequence over which to apply positional embeddings.
+    """
+
+    @register_to_config
+    def __init__(
+        self,
+        num_attention_heads: int = 16,
+        attention_head_dim: int = 88,
+        in_channels: Optional[int] = None,
+        out_channels: Optional[int] = None,
+        num_layers: int = 1,
+        dropout: float = 0.0,
+        norm_num_groups: int = 32,
+        cross_attention_dim: Optional[int] = None,
+        attention_bias: bool = False,
+        sample_size: Optional[int] = None,
+        activation_fn: str = "geglu",
+        norm_elementwise_affine: bool = True,
+        double_self_attention: bool = True,
+        positional_embeddings: Optional[str] = None,
+        num_positional_embeddings: Optional[int] = None,
+    ):
+        super().__init__()
+        self.num_attention_heads = num_attention_heads
+        self.attention_head_dim = attention_head_dim
+        inner_dim = num_attention_heads * attention_head_dim
+
+        self.in_channels = in_channels
+
+        self.norm = torch.nn.GroupNorm(num_groups=norm_num_groups, num_channels=in_channels, eps=1e-6, affine=True)
+        self.proj_in = nn.Linear(in_channels, inner_dim)
+
+        # 3. Define transformers blocks
+        self.transformer_blocks = nn.ModuleList(
+            [
+                BasicTransformerBlock(
+                    inner_dim,
+                    num_attention_heads,
+                    attention_head_dim,
+                    dropout=dropout,
+                    cross_attention_dim=cross_attention_dim,
+                    activation_fn=activation_fn,
+                    attention_bias=attention_bias,
+                    double_self_attention=double_self_attention,
+                    norm_elementwise_affine=norm_elementwise_affine,
+                    positional_embeddings=positional_embeddings,
+                    num_positional_embeddings=num_positional_embeddings,
+                )
+                for d in range(num_layers)
+            ]
+        )
+
+        self.proj_out = nn.Linear(inner_dim, in_channels)
+
+    def forward(
+        self,
+        hidden_states: torch.FloatTensor,
+        encoder_hidden_states: Optional[torch.LongTensor] = None,
+        timestep: Optional[torch.LongTensor] = None,
+        class_labels: torch.LongTensor = None,
+        num_frames: int = 1,
+        cross_attention_kwargs: Optional[Dict[str, Any]] = None,
+        return_dict: bool = True,
+    ) -> TransformerTemporalModelOutput:
+        """
+        The [`TransformerTemporal`] forward method.
+
+        Args:
+            hidden_states (`torch.LongTensor` of shape `(batch size, num latent pixels)` if discrete, `torch.FloatTensor` of shape `(batch size, channel, height, width)` if continuous):
+                Input hidden_states.
+            encoder_hidden_states ( `torch.LongTensor` of shape `(batch size, encoder_hidden_states dim)`, *optional*):
+                Conditional embeddings for cross attention layer. If not given, cross-attention defaults to
+                self-attention.
+            timestep ( `torch.LongTensor`, *optional*):
+                Used to indicate denoising step. Optional timestep to be applied as an embedding in `AdaLayerNorm`.
+            class_labels ( `torch.LongTensor` of shape `(batch size, num classes)`, *optional*):
+                Used to indicate class labels conditioning. Optional class labels to be applied as an embedding in
+                `AdaLayerZeroNorm`.
+            num_frames (`int`, *optional*, defaults to 1):
+                The number of frames to be processed per batch. This is used to reshape the hidden states.
+            cross_attention_kwargs (`dict`, *optional*):
+                A kwargs dictionary that if specified is passed along to the `AttentionProcessor` as defined under
+                `self.processor` in
+                [diffusers.models.attention_processor](https://github.com/huggingface/diffusers/blob/main/src/diffusers/models/attention_processor.py).
+            return_dict (`bool`, *optional*, defaults to `True`):
+                Whether or not to return a [`~models.unets.unet_2d_condition.UNet2DConditionOutput`] instead of a plain
+                tuple.
+
+        Returns:
+            [`~models.transformer_temporal.TransformerTemporalModelOutput`] or `tuple`:
+                If `return_dict` is True, an [`~models.transformer_temporal.TransformerTemporalModelOutput`] is
+                returned, otherwise a `tuple` where the first element is the sample tensor.
+        """
+        # 1. Input
+        batch_frames, channel, height, width = hidden_states.shape
+        batch_size = batch_frames // num_frames
+
+        residual = hidden_states
+
+        hidden_states = hidden_states[None, :].reshape(batch_size, num_frames, channel, height, width)
+        hidden_states = hidden_states.permute(0, 2, 1, 3, 4)
+
+        hidden_states = self.norm(hidden_states)
+        hidden_states = hidden_states.permute(0, 3, 4, 2, 1).reshape(batch_size * height * width, num_frames, channel)
+
+        hidden_states = self.proj_in(hidden_states)
+
+        # 2. Blocks
+        for block in self.transformer_blocks:
+            hidden_states = block(
+                hidden_states,
+                encoder_hidden_states=encoder_hidden_states,
+                timestep=timestep,
+                cross_attention_kwargs=cross_attention_kwargs,
+                class_labels=class_labels,
+            )
+
+        # 3. Output
+        hidden_states = self.proj_out(hidden_states)
+        hidden_states = (
+            hidden_states[None, None, :]
+            .reshape(batch_size, height, width, num_frames, channel)
+            .permute(0, 3, 4, 1, 2)
+            .contiguous()
+        )
+        hidden_states = hidden_states.reshape(batch_frames, channel, height, width)
+
+        output = hidden_states + residual
+
+        if not return_dict:
+            return (output,)
+
+        return TransformerTemporalModelOutput(sample=output)
+
+
+class TransformerSpatioTemporalModel(nn.Module):
+    """
+    A Transformer model for video-like data.
+
+    Parameters:
+        num_attention_heads (`int`, *optional*, defaults to 16): The number of heads to use for multi-head attention.
+        attention_head_dim (`int`, *optional*, defaults to 88): The number of channels in each head.
+        in_channels (`int`, *optional*):
+            The number of channels in the input and output (specify if the input is **continuous**).
+        out_channels (`int`, *optional*):
+            The number of channels in the output (specify if the input is **continuous**).
+        num_layers (`int`, *optional*, defaults to 1): The number of layers of Transformer blocks to use.
+        cross_attention_dim (`int`, *optional*): The number of `encoder_hidden_states` dimensions to use.
+    """
+
+    def __init__(
+        self,
+        num_attention_heads: int = 16,
+        attention_head_dim: int = 88,
+        in_channels: int = 320,
+        out_channels: Optional[int] = None,
+        num_layers: int = 1,
+        cross_attention_dim: Optional[int] = None,
+    ):
+        super().__init__()
+        self.num_attention_heads = num_attention_heads
+        self.attention_head_dim = attention_head_dim
+
+        inner_dim = num_attention_heads * attention_head_dim
+        self.inner_dim = inner_dim
+
+        # 2. Define input layers
+        self.in_channels = in_channels
+        self.norm = torch.nn.GroupNorm(num_groups=32, num_channels=in_channels, eps=1e-6)
+        self.proj_in = nn.Linear(in_channels, inner_dim)
+
+        # 3. Define transformers blocks
+        self.transformer_blocks = nn.ModuleList(
+            [
+                BasicTransformerBlock(
+                    inner_dim,
+                    num_attention_heads,
+                    attention_head_dim,
+                    cross_attention_dim=cross_attention_dim,
+                )
+                for d in range(num_layers)
+            ]
+        )
+
+        time_mix_inner_dim = inner_dim
+        self.temporal_transformer_blocks = nn.ModuleList(
+            [
+                TemporalBasicTransformerBlock(
+                    inner_dim,
+                    time_mix_inner_dim,
+                    num_attention_heads,
+                    attention_head_dim,
+                    cross_attention_dim=cross_attention_dim,
+                )
+                for _ in range(num_layers)
+            ]
+        )
+
+        time_embed_dim = in_channels * 4
+        self.time_pos_embed = TimestepEmbedding(in_channels, time_embed_dim, out_dim=in_channels)
+        self.time_proj = Timesteps(in_channels, True, 0)
+        self.time_mixer = AlphaBlender(alpha=0.5, merge_strategy="learned_with_images")
+
+        # 4. Define output layers
+        self.out_channels = in_channels if out_channels is None else out_channels
+        # TODO: should use out_channels for continuous projections
+        self.proj_out = nn.Linear(inner_dim, in_channels)
+
+        self.gradient_checkpointing = False
+
+    def forward(
+        self,
+        hidden_states: torch.Tensor,
+        encoder_hidden_states: Optional[torch.Tensor] = None,
+        image_only_indicator: Optional[torch.Tensor] = None,
+        return_dict: bool = True,
+    ):
+        """
+        Args:
+            hidden_states (`torch.FloatTensor` of shape `(batch size, channel, height, width)`):
+                Input hidden_states.
+            num_frames (`int`):
+                The number of frames to be processed per batch. This is used to reshape the hidden states.
+            encoder_hidden_states ( `torch.LongTensor` of shape `(batch size, encoder_hidden_states dim)`, *optional*):
+                Conditional embeddings for cross attention layer. If not given, cross-attention defaults to
+                self-attention.
+            image_only_indicator (`torch.LongTensor` of shape `(batch size, num_frames)`, *optional*):
+                A tensor indicating whether the input contains only images. 1 indicates that the input contains only
+                images, 0 indicates that the input contains video frames.
+            return_dict (`bool`, *optional*, defaults to `True`):
+                Whether or not to return a [`~models.transformer_temporal.TransformerTemporalModelOutput`] instead of a plain
+                tuple.
+
+        Returns:
+            [`~models.transformer_temporal.TransformerTemporalModelOutput`] or `tuple`:
+                If `return_dict` is True, an [`~models.transformer_temporal.TransformerTemporalModelOutput`] is
+                returned, otherwise a `tuple` where the first element is the sample tensor.
+        """
+        # 1. Input
+        batch_frames, _, height, width = hidden_states.shape
+        num_frames = image_only_indicator.shape[-1]
+        batch_size = batch_frames // num_frames
+
+        time_context = encoder_hidden_states
+        time_context_first_timestep = time_context[None, :].reshape(
+            batch_size, num_frames, -1, time_context.shape[-1]
+        )[:, 0]
+        time_context = time_context_first_timestep[None, :].broadcast_to(
+            height * width, batch_size, 1, time_context.shape[-1]
+        )
+        time_context = time_context.reshape(height * width * batch_size, 1, time_context.shape[-1])
+
+        residual = hidden_states
+
+        hidden_states = self.norm(hidden_states)
+        inner_dim = hidden_states.shape[1]
+        hidden_states = hidden_states.permute(0, 2, 3, 1).reshape(batch_frames, height * width, inner_dim)
+        hidden_states = self.proj_in(hidden_states)
+
+        num_frames_emb = torch.arange(num_frames, device=hidden_states.device)
+        num_frames_emb = num_frames_emb.repeat(batch_size, 1)
+        num_frames_emb = num_frames_emb.reshape(-1)
+        t_emb = self.time_proj(num_frames_emb)
+
+        # `Timesteps` does not contain any weights and will always return f32 tensors
+        # but time_embedding might actually be running in fp16. so we need to cast here.
+        # there might be better ways to encapsulate this.
+        t_emb = t_emb.to(dtype=hidden_states.dtype)
+
+        emb = self.time_pos_embed(t_emb)
+        emb = emb[:, None, :]
+
+        # 2. Blocks
+        for block, temporal_block in zip(self.transformer_blocks, self.temporal_transformer_blocks):
+            if self.training and self.gradient_checkpointing:
+                hidden_states = torch.utils.checkpoint.checkpoint(
+                    block,
+                    hidden_states,
+                    None,
+                    encoder_hidden_states,
+                    None,
+                    use_reentrant=False,
+                )
+            else:
+                hidden_states = block(
+                    hidden_states,
+                    encoder_hidden_states=encoder_hidden_states,
+                )
+
+            hidden_states_mix = hidden_states
+            hidden_states_mix = hidden_states_mix + emb
+
+            hidden_states_mix = temporal_block(
+                hidden_states_mix,
+                num_frames=num_frames,
+                encoder_hidden_states=time_context,
+            )
+            hidden_states = self.time_mixer(
+                x_spatial=hidden_states,
+                x_temporal=hidden_states_mix,
+                image_only_indicator=image_only_indicator,
+            )
+
+        # 3. Output
+        hidden_states = self.proj_out(hidden_states)
+        hidden_states = hidden_states.reshape(batch_frames, height, width, inner_dim).permute(0, 3, 1, 2).contiguous()
+
+        output = hidden_states + residual
+
+        if not return_dict:
+            return (output,)
+
+        return TransformerTemporalModelOutput(sample=output)

src/diffusers/models/unets/unet_2d_blocks.py

@@ -22,7 +22,6 @@ from ...utils import is_torch_version, logging
 from ...utils.torch_utils import apply_freeu
 from ..activations import get_activation
 from ..attention_processor import Attention, AttnAddedKVProcessor, AttnAddedKVProcessor2_0
-from ..dual_transformer_2d import DualTransformer2DModel
 from ..normalization import AdaGroupNorm
 from ..resnet import (
     Downsample2D,
@@ -34,7 +33,8 @@ from ..resnet import (
     ResnetBlockCondNorm2D,
     Upsample2D,
 )
-from ..transformer_2d import Transformer2DModel
+from ..transformers.dual_transformer_2d import DualTransformer2DModel
+from ..transformers.transformer_2d import Transformer2DModel
 
 
 logger = logging.get_logger(__name__)  # pylint: disable=invalid-name

src/diffusers/models/unets/unet_3d_blocks.py

@@ -20,7 +20,6 @@ from torch import nn
 from ...utils import is_torch_version
 from ...utils.torch_utils import apply_freeu
 from ..attention import Attention
-from ..dual_transformer_2d import DualTransformer2DModel
 from ..resnet import (
     Downsample2D,
     ResnetBlock2D,
@@ -28,8 +27,9 @@ from ..resnet import (
     TemporalConvLayer,
     Upsample2D,
 )
-from ..transformer_2d import Transformer2DModel
-from ..transformer_temporal import (
+from ..transformers.dual_transformer_2d import DualTransformer2DModel
+from ..transformers.transformer_2d import Transformer2DModel
+from ..transformers.transformer_temporal import (
     TransformerSpatioTemporalModel,
     TransformerTemporalModel,
 )