diff --git "a/llama/musicgen/musicgen.py" "b/llama/musicgen/musicgen.py"
new file mode 100644--- /dev/null
+++ "b/llama/musicgen/musicgen.py"
@@ -0,0 +1,2483 @@
+# coding=utf-8
+# Copyright 2023 Meta AI and The HuggingFace Inc. 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.
+""" PyTorch Musicgen model."""
+import copy
+import inspect
+import math
+import random
+from dataclasses import dataclass
+from typing import TYPE_CHECKING, Any, Dict, Optional, Tuple, Union
+
+import torch
+import torch.nn as nn
+from torch.nn import CrossEntropyLoss
+
+from transformers.activations import ACT2FN
+from transformers.generation.configuration_utils import GenerationConfig
+from transformers.generation.logits_process import ClassifierFreeGuidanceLogitsProcessor, LogitsProcessorList
+from transformers.generation.stopping_criteria import StoppingCriteriaList
+from .modeling_attn_mask_utils import _prepare_4d_attention_mask, _prepare_4d_causal_attention_mask
+from transformers.modeling_outputs import (
+ BaseModelOutput,
+ BaseModelOutputWithPastAndCrossAttentions,
+ CausalLMOutputWithCrossAttentions,
+ ModelOutput,
+ Seq2SeqLMOutput,
+)
+from transformers.modeling_utils import PreTrainedModel
+from transformers.utils import (
+ add_start_docstrings,
+ add_start_docstrings_to_model_forward,
+ logging,
+ replace_return_docstrings,
+)
+from transformers.models.auto.configuration_auto import AutoConfig
+from transformers.models.auto.modeling_auto import AutoModel
+from .configuration_musicgen import MusicgenConfig, MusicgenDecoderConfig
+
+
+if TYPE_CHECKING:
+ from ...generation.streamers import BaseStreamer
+
+logger = logging.get_logger(__name__)
+
+_CONFIG_FOR_DOC = "MusicgenConfig"
+_CHECKPOINT_FOR_DOC = "facebook/musicgen-small"
+
+MUSICGEN_PRETRAINED_MODEL_ARCHIVE_LIST = [
+ "facebook/musicgen-small",
+ # See all Musicgen models at https://huggingface.co/models?filter=musicgen
+]
+
+
+@dataclass
+class MusicgenUnconditionalInput(ModelOutput):
+ """
+ Args:
+ encoder_outputs (`Tuple[torch.FloatTensor]` of length 1, with tensor shape `(batch_size, sequence_length, hidden_size)`):
+ Sequence of hidden-states at the output of the last layer of the text encoder model.
+ attention_mask (`torch.LongTensor`) of shape `(batch_size, sequence_length)`, *optional*):
+ Encoder attention mask to avoid performing attention on padding token indices. Mask values selected in `[0,
+ 1]`: 1 for tokens that are **not masked**, 0 for tokens that are **masked**.
+ guidance_scale (`float`, *optional*):
+ Guidance scale for classifier free guidance, setting the balance between the conditional logits (predicted
+ from the prompts) and the unconditional logits (predicted without prompts).
+ """
+
+ encoder_outputs: Tuple[torch.FloatTensor] = None
+ attention_mask: torch.LongTensor = None
+ guidance_scale: float = None
+
+
+# Copied from transformers.models.encoder_decoder.modeling_encoder_decoder.shift_tokens_right
+def shift_tokens_right(input_ids: torch.Tensor, pad_token_id: int, decoder_start_token_id: int):
+ """
+ Shift input ids one token to the right.
+ """
+ shifted_input_ids = input_ids.new_zeros(input_ids.shape)
+ shifted_input_ids[:, 1:] = input_ids[:, :-1].clone()
+ if decoder_start_token_id is None:
+ raise ValueError("Make sure to set the decoder_start_token_id attribute of the model's configuration.")
+ shifted_input_ids[:, 0] = decoder_start_token_id
+
+ if pad_token_id is None:
+ raise ValueError("Make sure to set the pad_token_id attribute of the model's configuration.")
+ # replace possible -100 values in labels by `pad_token_id`
+ shifted_input_ids.masked_fill_(shifted_input_ids == -100, pad_token_id)
+
+ return shifted_input_ids
+
+
+class MusicgenSinusoidalPositionalEmbedding(nn.Module):
+ """This module produces sinusoidal positional embeddings of any length."""
+
+ def __init__(self, num_positions: int, embedding_dim: int):
+ super().__init__()
+ self.embedding_dim = embedding_dim
+ self.make_weights(num_positions, embedding_dim)
+
+ def make_weights(self, num_embeddings: int, embedding_dim: int):
+ emb_weights = self.get_embedding(num_embeddings, embedding_dim)
+ if hasattr(self, "weights"):
+ # in forward put the weights on the correct dtype and device of the param
+ emb_weights = emb_weights.to(dtype=self.weights.dtype, device=self.weights.device)
+
+ self.weights = nn.Parameter(emb_weights)
+ self.weights.requires_grad = False
+ self.weights.detach_()
+
+ @staticmethod
+ def get_embedding(num_embeddings: int, embedding_dim: int):
+ """
+ Build sinusoidal embeddings. This matches the implementation in tensor2tensor, but differs slightly from the
+ description in Section 3.5 of "Attention Is All You Need".
+ """
+ half_dim = embedding_dim // 2
+ emb = math.log(10000) / (half_dim - 1)
+ emb = torch.exp(torch.arange(half_dim, dtype=torch.float) * -emb)
+ emb = torch.arange(num_embeddings, dtype=torch.float).unsqueeze(1) * emb.unsqueeze(0)
+ emb = torch.cat([torch.cos(emb), torch.sin(emb)], dim=1).view(num_embeddings, -1)
+ if embedding_dim % 2 == 1:
+ # zero pad
+ emb = torch.cat([emb, torch.zeros(num_embeddings, 1)], dim=1)
+ return emb.to(torch.get_default_dtype())
+
+ @torch.no_grad()
+ def forward(self, input_ids: torch.Tensor, past_key_values_length: int = 0):
+ bsz, codebooks, seq_len = input_ids.size()
+ # Create the position ids from the input token ids.
+ position_ids = (torch.arange(seq_len) + past_key_values_length).to(input_ids.device)
+ # expand embeddings if needed
+ if seq_len > self.weights.size(0):
+ self.make_weights(seq_len + self.offset, self.embedding_dim)
+ return self.weights.index_select(0, position_ids.view(-1)).detach()
+
+
+# Copied from transformers.models.bart.modeling_bart.BartAttention with Bart->Musicgen
+class MusicgenAttention(nn.Module):
+ """Multi-headed attention from 'Attention Is All You Need' paper"""
+
+ def __init__(
+ self,
+ embed_dim: int,
+ num_heads: int,
+ dropout: float = 0.0,
+ is_decoder: bool = False,
+ bias: bool = True,
+ is_causal: bool = False,
+ config: Optional[MusicgenConfig] = None,
+ ):
+ super().__init__()
+ self.embed_dim = embed_dim
+ self.num_heads = num_heads
+ self.dropout = dropout
+ self.head_dim = embed_dim // num_heads
+ self.config = config
+
+ if (self.head_dim * num_heads) != self.embed_dim:
+ raise ValueError(
+ f"embed_dim must be divisible by num_heads (got `embed_dim`: {self.embed_dim}"
+ f" and `num_heads`: {num_heads})."
+ )
+ self.scaling = self.head_dim**-0.5
+ self.is_decoder = is_decoder
+ self.is_causal = is_causal
+
+ self.k_proj = nn.Linear(embed_dim, embed_dim, bias=bias)
+ self.v_proj = nn.Linear(embed_dim, embed_dim, bias=bias)
+ self.q_proj = nn.Linear(embed_dim, embed_dim, bias=bias)
+ self.out_proj = nn.Linear(embed_dim, embed_dim, bias=bias)
+
+ def _shape(self, tensor: torch.Tensor, seq_len: int, bsz: int):
+ return tensor.view(bsz, seq_len, self.num_heads, self.head_dim).transpose(1, 2).contiguous()
+
+ def forward(
+ self,
+ hidden_states: torch.Tensor,
+ key_value_states: Optional[torch.Tensor] = None,
+ past_key_value: Optional[Tuple[torch.Tensor]] = None,
+ attention_mask: Optional[torch.Tensor] = None,
+ layer_head_mask: Optional[torch.Tensor] = None,
+ output_attentions: bool = False,
+ ) -> Tuple[torch.Tensor, Optional[torch.Tensor], Optional[Tuple[torch.Tensor]]]:
+ """Input shape: Batch x Time x Channel"""
+
+ # if key_value_states are provided this layer is used as a cross-attention layer
+ # for the decoder
+ is_cross_attention = key_value_states is not None
+
+ bsz, tgt_len, _ = hidden_states.size()
+
+ # get query proj
+ query_states = self.q_proj(hidden_states) * self.scaling
+ # get key, value proj
+ # `past_key_value[0].shape[2] == key_value_states.shape[1]`
+ # is checking that the `sequence_length` of the `past_key_value` is the same as
+ # the provided `key_value_states` to support prefix tuning
+ if (
+ is_cross_attention
+ and past_key_value is not None
+ and past_key_value[0].shape[2] == key_value_states.shape[1]
+ ):
+ # reuse k,v, cross_attentions
+ key_states = past_key_value[0]
+ value_states = past_key_value[1]
+ elif is_cross_attention:
+ # cross_attentions
+ key_states = self._shape(self.k_proj(key_value_states), -1, bsz)
+ value_states = self._shape(self.v_proj(key_value_states), -1, bsz)
+ elif past_key_value is not None:
+ # reuse k, v, self_attention
+ key_states = self._shape(self.k_proj(hidden_states), -1, bsz)
+ value_states = self._shape(self.v_proj(hidden_states), -1, bsz)
+ key_states = torch.cat([past_key_value[0], key_states], dim=2)
+ value_states = torch.cat([past_key_value[1], value_states], dim=2)
+ else:
+ # self_attention
+ key_states = self._shape(self.k_proj(hidden_states), -1, bsz)
+ value_states = self._shape(self.v_proj(hidden_states), -1, bsz)
+
+ if self.is_decoder:
+ # if cross_attention save Tuple(torch.Tensor, torch.Tensor) of all cross attention key/value_states.
+ # Further calls to cross_attention layer can then reuse all cross-attention
+ # key/value_states (first "if" case)
+ # if uni-directional self-attention (decoder) save Tuple(torch.Tensor, torch.Tensor) of
+ # all previous decoder key/value_states. Further calls to uni-directional self-attention
+ # can concat previous decoder key/value_states to current projected key/value_states (third "elif" case)
+ # if encoder bi-directional self-attention `past_key_value` is always `None`
+ past_key_value = (key_states, value_states)
+
+ proj_shape = (bsz * self.num_heads, -1, self.head_dim)
+ query_states = self._shape(query_states, tgt_len, bsz).view(*proj_shape)
+ key_states = key_states.reshape(*proj_shape)
+ value_states = value_states.reshape(*proj_shape)
+
+ src_len = key_states.size(1)
+ attn_weights = torch.bmm(query_states, key_states.transpose(1, 2))
+
+ if attn_weights.size() != (bsz * self.num_heads, tgt_len, src_len):
+ raise ValueError(
+ f"Attention weights should be of size {(bsz * self.num_heads, tgt_len, src_len)}, but is"
+ f" {attn_weights.size()}"
+ )
+
+ if attention_mask is not None:
+ if attention_mask.size() != (bsz, 1, tgt_len, src_len):
+ raise ValueError(
+ f"Attention mask should be of size {(bsz, 1, tgt_len, src_len)}, but is {attention_mask.size()}"
+ )
+ attn_weights = attn_weights.view(bsz, self.num_heads, tgt_len, src_len) + attention_mask
+ attn_weights = attn_weights.view(bsz * self.num_heads, tgt_len, src_len)
+
+ attn_weights = nn.functional.softmax(attn_weights, dim=-1)
+
+ if layer_head_mask is not None:
+ if layer_head_mask.size() != (self.num_heads,):
+ raise ValueError(
+ f"Head mask for a single layer should be of size {(self.num_heads,)}, but is"
+ f" {layer_head_mask.size()}"
+ )
+ attn_weights = layer_head_mask.view(1, -1, 1, 1) * attn_weights.view(bsz, self.num_heads, tgt_len, src_len)
+ attn_weights = attn_weights.view(bsz * self.num_heads, tgt_len, src_len)
+
+ if output_attentions:
+ # this operation is a bit awkward, but it's required to
+ # make sure that attn_weights keeps its gradient.
+ # In order to do so, attn_weights have to be reshaped
+ # twice and have to be reused in the following
+ attn_weights_reshaped = attn_weights.view(bsz, self.num_heads, tgt_len, src_len)
+ attn_weights = attn_weights_reshaped.view(bsz * self.num_heads, tgt_len, src_len)
+ else:
+ attn_weights_reshaped = None
+
+ attn_probs = nn.functional.dropout(attn_weights, p=self.dropout, training=self.training)
+
+ attn_output = torch.bmm(attn_probs, value_states)
+
+ if attn_output.size() != (bsz * self.num_heads, tgt_len, self.head_dim):
+ raise ValueError(
+ f"`attn_output` should be of size {(bsz * self.num_heads, tgt_len, self.head_dim)}, but is"
+ f" {attn_output.size()}"
+ )
+
+ attn_output = attn_output.view(bsz, self.num_heads, tgt_len, self.head_dim)
+ attn_output = attn_output.transpose(1, 2)
+
+ # Use the `embed_dim` from the config (stored in the class) rather than `hidden_state` because `attn_output` can be
+ # partitioned across GPUs when using tensor-parallelism.
+ attn_output = attn_output.reshape(bsz, tgt_len, self.embed_dim)
+
+ attn_output = self.out_proj(attn_output)
+
+ return attn_output, attn_weights_reshaped, past_key_value
+
+
+class MusicgenDecoderLayer(nn.Module):
+ def __init__(self, config: MusicgenDecoderConfig):
+ super().__init__()
+ self.embed_dim = config.hidden_size
+
+ self.self_attn = MusicgenAttention(
+ embed_dim=self.embed_dim,
+ num_heads=config.num_attention_heads,
+ dropout=config.attention_dropout,
+ is_decoder=True,
+ bias=False,
+ )
+ self.dropout = config.dropout
+ self.activation_fn = ACT2FN[config.activation_function]
+ self.activation_dropout = config.activation_dropout
+
+ self.self_attn_layer_norm = nn.LayerNorm(self.embed_dim)
+ self.encoder_attn = MusicgenAttention(
+ self.embed_dim,
+ config.num_attention_heads,
+ dropout=config.attention_dropout,
+ is_decoder=True,
+ bias=False,
+ )
+ self.encoder_attn_layer_norm = nn.LayerNorm(self.embed_dim)
+ self.fc1 = nn.Linear(self.embed_dim, config.ffn_dim, bias=False)
+ self.fc2 = nn.Linear(config.ffn_dim, self.embed_dim, bias=False)
+ self.final_layer_norm = nn.LayerNorm(self.embed_dim)
+
+ # Copied from transformers.models.mbart.modeling_mbart.MBartDecoderLayer.forward
+ def forward(
+ self,
+ hidden_states: torch.Tensor,
+ attention_mask: Optional[torch.Tensor] = None,
+ encoder_hidden_states: Optional[torch.Tensor] = None,
+ encoder_attention_mask: Optional[torch.Tensor] = None,
+ layer_head_mask: Optional[torch.Tensor] = None,
+ cross_attn_layer_head_mask: Optional[torch.Tensor] = None,
+ past_key_value: Optional[Tuple[torch.Tensor]] = None,
+ output_attentions: Optional[bool] = False,
+ use_cache: Optional[bool] = True,
+ ) -> torch.Tensor:
+ """
+ Args:
+ hidden_states (`torch.FloatTensor`): input to the layer of shape `(batch, seq_len, embed_dim)`
+ attention_mask (`torch.FloatTensor`): attention mask of size
+ `(batch, 1, tgt_len, src_len)` where padding elements are indicated by very large negative values.
+ encoder_hidden_states (`torch.FloatTensor`):
+ cross attention input to the layer of shape `(batch, seq_len, embed_dim)`
+ encoder_attention_mask (`torch.FloatTensor`): encoder attention mask of size
+ `(batch, 1, tgt_len, src_len)` where padding elements are indicated by very large negative values.
+ layer_head_mask (`torch.FloatTensor`): mask for attention heads in a given layer of size
+ `(encoder_attention_heads,)`.
+ cross_attn_layer_head_mask (`torch.FloatTensor`): mask for cross-attention heads in a given layer of
+ size `(decoder_attention_heads,)`.
+ past_key_value (`Tuple(torch.FloatTensor)`): cached past key and value projection states
+ output_attentions (`bool`, *optional*):
+ Whether or not to return the attentions tensors of all attention layers. See `attentions` under
+ returned tensors for more detail.
+ """
+ residual = hidden_states
+ hidden_states = self.self_attn_layer_norm(hidden_states)
+
+ # Self Attention
+ # decoder uni-directional self-attention cached key/values tuple is at positions 1,2
+ self_attn_past_key_value = past_key_value[:2] if past_key_value is not None else None
+ # add present self-attn cache to positions 1,2 of present_key_value tuple
+ hidden_states, self_attn_weights, present_key_value = self.self_attn(
+ hidden_states=hidden_states,
+ past_key_value=self_attn_past_key_value,
+ attention_mask=attention_mask,
+ layer_head_mask=layer_head_mask,
+ output_attentions=output_attentions,
+ )
+ hidden_states = nn.functional.dropout(hidden_states, p=self.dropout, training=self.training)
+ hidden_states = residual + hidden_states
+
+ # Cross-Attention Block
+ cross_attn_present_key_value = None
+ cross_attn_weights = None
+ if encoder_hidden_states is not None:
+ residual = hidden_states
+ hidden_states = self.encoder_attn_layer_norm(hidden_states)
+
+ # cross_attn cached key/values tuple is at positions 3,4 of present_key_value tuple
+ cross_attn_past_key_value = past_key_value[-2:] if past_key_value is not None else None
+ hidden_states, cross_attn_weights, cross_attn_present_key_value = self.encoder_attn(
+ hidden_states=hidden_states,
+ key_value_states=encoder_hidden_states,
+ attention_mask=encoder_attention_mask,
+ layer_head_mask=cross_attn_layer_head_mask,
+ past_key_value=cross_attn_past_key_value,
+ output_attentions=output_attentions,
+ )
+ hidden_states = nn.functional.dropout(hidden_states, p=self.dropout, training=self.training)
+ hidden_states = residual + hidden_states
+
+ # add cross-attn to positions 3,4 of present_key_value tuple
+ present_key_value = present_key_value + cross_attn_present_key_value
+
+ # Fully Connected
+ residual = hidden_states
+ hidden_states = self.final_layer_norm(hidden_states)
+ hidden_states = self.activation_fn(self.fc1(hidden_states))
+ hidden_states = nn.functional.dropout(hidden_states, p=self.activation_dropout, training=self.training)
+ hidden_states = self.fc2(hidden_states)
+ hidden_states = nn.functional.dropout(hidden_states, p=self.dropout, training=self.training)
+ hidden_states = residual + hidden_states
+
+ outputs = (hidden_states,)
+
+ if output_attentions:
+ outputs += (self_attn_weights, cross_attn_weights)
+
+ if use_cache:
+ outputs += (present_key_value,)
+
+ return outputs
+
+
+class MusicgenPreTrainedModel(PreTrainedModel):
+ """
+ An abstract class to handle weights initialization and a simple interface for downloading and loading pretrained
+ models.
+ """
+
+ config_class = MusicgenDecoderConfig
+ base_model_prefix = "model"
+ supports_gradient_checkpointing = True
+ _no_split_modules = ["MusicgenDecoderLayer", "MusicgenAttention"]
+
+ def _init_weights(self, module):
+ std = self.config.initializer_factor
+ if isinstance(module, (nn.Linear, nn.Conv1d)):
+ module.weight.data.normal_(mean=0.0, std=std)
+ if module.bias is not None:
+ module.bias.data.zero_()
+ elif isinstance(module, nn.Embedding):
+ module.weight.data.normal_(mean=0.0, std=std)
+ if module.padding_idx is not None:
+ module.weight.data[module.padding_idx].zero_()
+
+
+MUSICGEN_START_DOCSTRING = r"""
+
+ The Musicgen model was proposed in [Simple and Controllable Music Generation](https://arxiv.org/abs/2306.05284) by
+ Jade Copet, Felix Kreuk, Itai Gat, Tal Remez, David Kant, Gabriel Synnaeve, Yossi Adi, Alexandre Défossez. It is an
+ encoder decoder transformer trained on the task of conditional music generation
+
+ This model inherits from [`PreTrainedModel`]. Check the superclass documentation for the generic methods the
+ library implements for all its model (such as downloading or saving, resizing the input embeddings, pruning heads
+ etc.)
+
+ This model is also a PyTorch [torch.nn.Module](https://pytorch.org/docs/stable/nn.html#torch.nn.Module) subclass.
+ Use it as a regular PyTorch Module and refer to the PyTorch documentation for all matter related to general usage
+ and behavior.
+
+ Parameters:
+ config ([`MusicgenConfig`]): Model configuration class with all the parameters of the model.
+ Initializing with a config file does not load the weights associated with the model, only the
+ configuration. Check out the [`~PreTrainedModel.from_pretrained`] method to load the model weights.
+"""
+
+MUSICGEN_INPUTS_DOCSTRING = r"""
+ Args:
+ input_ids (`torch.LongTensor` of shape `(batch_size, sequence_length)`):
+ Indices of input sequence tokens in the vocabulary. Padding will be ignored by default should you provide
+ it.
+
+ Indices can be obtained using [`AutoTokenizer`]. See [`PreTrainedTokenizer.encode`] and
+ [`PreTrainedTokenizer.__call__`] for details.
+
+ [What are input IDs?](../glossary#input-ids)
+ attention_mask (`torch.Tensor` of shape `(batch_size, sequence_length)`, *optional*):
+ Mask to avoid performing attention on padding token indices. Mask values selected in `[0, 1]`:
+
+ - 1 for tokens that are **not masked**,
+ - 0 for tokens that are **masked**.
+
+ [What are attention masks?](../glossary#attention-mask)
+ decoder_input_ids (`torch.LongTensor` of shape `(batch_size * num_codebooks, target_sequence_length)`, *optional*):
+ Indices of decoder input sequence tokens in the vocabulary, corresponding to the sequence of audio codes.
+
+ Indices can be obtained by encoding an audio prompt with an audio encoder model to predict audio codes,
+ such as with the [`EncodecModel`]. See [`EncodecModel.encode`] for details.
+
+ [What are decoder input IDs?](../glossary#decoder-input-ids)
+
+
+
+ The `decoder_input_ids` will automatically be converted from shape `(batch_size * num_codebooks,
+ target_sequence_length)` to `(batch_size, num_codebooks, target_sequence_length)` in the forward pass. If
+ you obtain audio codes from an audio encoding model, such as [`EncodecModel`], ensure that the number of
+ frames is equal to 1, and that you reshape the audio codes from `(frames, batch_size, num_codebooks,
+ target_sequence_length)` to `(batch_size * num_codebooks, target_sequence_length)` prior to passing them as
+ `decoder_input_ids`.
+
+
+
+ decoder_attention_mask (`torch.LongTensor` of shape `(batch_size, target_sequence_length)`, *optional*):
+ Default behavior: generate a tensor that ignores pad tokens in `decoder_input_ids`. Causal mask will also
+ be used by default.
+ head_mask (`torch.Tensor` of shape `(encoder_layers, encoder_attention_heads)`, *optional*):
+ Mask to nullify selected heads of the attention modules in the encoder. Mask values selected in `[0, 1]`:
+
+ - 1 indicates the head is **not masked**,
+ - 0 indicates the head is **masked**.
+
+ decoder_head_mask (`torch.Tensor` of shape `(decoder_layers, decoder_attention_heads)`, *optional*):
+ Mask to nullify selected heads of the attention modules in the decoder. Mask values selected in `[0, 1]`:
+
+ - 1 indicates the head is **not masked**,
+ - 0 indicates the head is **masked**.
+
+ cross_attn_head_mask (`torch.Tensor` of shape `(decoder_layers, decoder_attention_heads)`, *optional*):
+ Mask to nullify selected heads of the cross-attention modules in the decoder. Mask values selected in `[0,
+ 1]`:
+
+ - 1 indicates the head is **not masked**,
+ - 0 indicates the head is **masked**.
+
+ encoder_outputs (`tuple(tuple(torch.FloatTensor)`, *optional*):
+ Tuple consists of (`last_hidden_state`, *optional*: `hidden_states`, *optional*: `attentions`)
+ `last_hidden_state` of shape `(batch_size, sequence_length, hidden_size)`, *optional*) is a sequence of
+ hidden-states at the output of the last layer of the encoder. Used in the cross-attention of the decoder.
+ past_key_values (`tuple(tuple(torch.FloatTensor))`, *optional*, returned when `use_cache=True` is passed or when `config.use_cache=True`):
+ Tuple of `tuple(torch.FloatTensor)` of length `config.n_layers`, with each tuple having 2 tensors of shape
+ `(batch_size, num_heads, sequence_length, embed_size_per_head)`) and 2 additional tensors of shape
+ `(batch_size, num_heads, encoder_sequence_length, embed_size_per_head)`.
+
+ Contains pre-computed hidden-states (key and values in the self-attention blocks and in the cross-attention
+ blocks) that can be used (see `past_key_values` input) to speed up sequential decoding.
+
+ If `past_key_values` are used, the user can optionally input only the last `decoder_input_ids` (those that
+ don't have their past key value states given to this model) of shape `(batch_size, 1)` instead of all
+ `decoder_input_ids` of shape `(batch_size, sequence_length)`. inputs_embeds (`torch.FloatTensor` of shape
+ `(batch_size, sequence_length, hidden_size)`, *optional*): Optionally, instead of passing `input_ids` you
+ can choose to directly pass an embedded representation. This is useful if you want more control over how to
+ convert `input_ids` indices into associated vectors than the model's internal embedding lookup matrix.
+ decoder_inputs_embeds (`torch.FloatTensor` of shape `(batch_size, target_sequence_length, hidden_size)`, *optional*):
+ Optionally, instead of passing `decoder_input_ids` you can choose to directly pass an embedded
+ representation. If `past_key_values` is used, optionally only the last `decoder_inputs_embeds` have to be
+ input (see `past_key_values`). This is useful if you want more control over how to convert
+ `decoder_input_ids` indices into associated vectors than the model's internal embedding lookup matrix.
+
+ If `decoder_input_ids` and `decoder_inputs_embeds` are both unset, `decoder_inputs_embeds` takes the value
+ of `inputs_embeds`.
+ use_cache (`bool`, *optional*):
+ If set to `True`, `past_key_values` key value states are returned and can be used to speed up decoding (see
+ `past_key_values`).
+ output_attentions (`bool`, *optional*):
+ Whether or not to return the attentions tensors of all attention layers. See `attentions` under returned
+ tensors for more detail.
+ output_hidden_states (`bool`, *optional*):
+ Whether or not to return the hidden states of all layers. See `hidden_states` under returned tensors for
+ more detail.
+ return_dict (`bool`, *optional*):
+ Whether or not to return a [`~utils.ModelOutput`] instead of a plain tuple.
+"""
+
+MUSICGEN_DECODER_INPUTS_DOCSTRING = r"""
+ Args:
+ input_ids (`torch.LongTensor` of shape `(batch_size * num_codebooks, sequence_length)`):
+ Indices of input sequence tokens in the vocabulary, corresponding to the sequence of audio codes.
+
+ Indices can be obtained by encoding an audio prompt with an audio encoder model to predict audio codes,
+ such as with the [`EncodecModel`]. See [`EncodecModel.encode`] for details.
+
+ [What are input IDs?](../glossary#input-ids)
+
+
+
+ The `input_ids` will automatically be converted from shape `(batch_size * num_codebooks,
+ target_sequence_length)` to `(batch_size, num_codebooks, target_sequence_length)` in the forward pass. If
+ you obtain audio codes from an audio encoding model, such as [`EncodecModel`], ensure that the number of
+ frames is equal to 1, and that you reshape the audio codes from `(frames, batch_size, num_codebooks,
+ target_sequence_length)` to `(batch_size * num_codebooks, target_sequence_length)` prior to passing them as
+ `input_ids`.
+
+
+
+ attention_mask (`torch.Tensor` of shape `(batch_size, sequence_length)`, *optional*):
+ Mask to avoid performing attention on padding token indices. Mask values selected in `[0, 1]`:
+
+ - 1 for tokens that are **not masked**,
+ - 0 for tokens that are **masked**.
+
+ [What are attention masks?](../glossary#attention-mask)
+ encoder_hidden_states (`torch.FloatTensor` of shape `(batch_size, encoder_sequence_length, hidden_size)`, *optional*):
+ Sequence of hidden-states at the output of the last layer of the encoder. Used in the cross-attention of
+ the decoder.
+ encoder_attention_mask (`torch.LongTensor` of shape `(batch_size, encoder_sequence_length)`, *optional*):
+ Mask to avoid performing cross-attention on padding tokens indices of encoder input_ids. Mask values
+ selected in `[0, 1]`:
+
+ - 1 for tokens that are **not masked**,
+ - 0 for tokens that are **masked**.
+
+ [What are attention masks?](../glossary#attention-mask)
+ head_mask (`torch.Tensor` of shape `(decoder_layers, decoder_attention_heads)`, *optional*):
+ Mask to nullify selected heads of the attention modules. Mask values selected in `[0, 1]`:
+
+ - 1 indicates the head is **not masked**,
+ - 0 indicates the head is **masked**.
+
+ cross_attn_head_mask (`torch.Tensor` of shape `(decoder_layers, decoder_attention_heads)`, *optional*):
+ Mask to nullify selected heads of the cross-attention modules in the decoder to avoid performing
+ cross-attention on hidden heads. Mask values selected in `[0, 1]`:
+
+ - 1 indicates the head is **not masked**,
+ - 0 indicates the head is **masked**.
+
+ past_key_values (`tuple(tuple(torch.FloatTensor))`, *optional*, returned when `use_cache=True` is passed or when `config.use_cache=True`):
+ Tuple of `tuple(torch.FloatTensor)` of length `config.n_layers`, with each tuple having 2 tensors of shape
+ `(batch_size, num_heads, sequence_length, embed_size_per_head)`) and 2 additional tensors of shape
+ `(batch_size, num_heads, encoder_sequence_length, embed_size_per_head)`.
+
+ Contains pre-computed hidden-states (key and values in the self-attention blocks and in the cross-attention
+ blocks) that can be used (see `past_key_values` input) to speed up sequential decoding.
+
+ If `past_key_values` are used, the user can optionally input only the last `decoder_input_ids` (those that
+ don't have their past key value states given to this model) of shape `(batch_size, 1)` instead of all
+ `decoder_input_ids` of shape `(batch_size, sequence_length)`. inputs_embeds (`torch.FloatTensor` of shape
+ `(batch_size, sequence_length, hidden_size)`, *optional*): Optionally, instead of passing `input_ids` you
+ can choose to directly pass an embedded representation. This is useful if you want more control over how to
+ convert `input_ids` indices into associated vectors than the model's internal embedding lookup matrix.
+ output_attentions (`bool`, *optional*):
+ Whether or not to return the attentions tensors of all attention layers. See `attentions` under returned
+ tensors for more detail.
+ output_hidden_states (`bool`, *optional*):
+ Whether or not to return the hidden states of all layers. See `hidden_states` under returned tensors for
+ more detail.
+ return_dict (`bool`, *optional*):
+ Whether or not to return a [`~utils.ModelOutput`] instead of a plain tuple.
+"""
+
+
+class MusicgenDecoder(MusicgenPreTrainedModel):
+ """
+ Transformer decoder consisting of *config.num_hidden_layers* layers. Each layer is a [`MusicgenDecoderLayer`]
+ """
+
+ def __init__(self, config: MusicgenDecoderConfig):
+ super().__init__(config)
+ self.dropout = config.dropout
+ self.layerdrop = config.layerdrop
+ self.max_target_positions = config.max_position_embeddings
+ self.d_model = config.hidden_size
+ self.num_codebooks = config.num_codebooks
+ self.embed_scale = math.sqrt(config.hidden_size) if config.scale_embedding else 1.0
+
+ embed_dim = config.vocab_size + 1
+ self.embed_tokens = nn.ModuleList(
+ [nn.Embedding(embed_dim, config.hidden_size) for _ in range(config.num_codebooks)]
+ )
+
+ self.embed_positions = MusicgenSinusoidalPositionalEmbedding(
+ config.max_position_embeddings,
+ config.hidden_size,
+ )
+
+ self.layers = nn.ModuleList([MusicgenDecoderLayer(config) for _ in range(config.num_hidden_layers)])
+ self.layer_norm = nn.LayerNorm(config.hidden_size)
+
+ self.gradient_checkpointing = False
+ # Initialize weights and apply final processing
+ self.post_init()
+
+ def get_input_embeddings(self):
+ return self.embed_tokens
+
+ def set_input_embeddings(self, value):
+ self.embed_tokens = value
+
+ @add_start_docstrings_to_model_forward(MUSICGEN_DECODER_INPUTS_DOCSTRING)
+ def forward(
+ self,
+ input_ids: torch.LongTensor = None,
+ attention_mask: Optional[torch.Tensor] = None,
+ encoder_hidden_states: Optional[torch.FloatTensor] = None,
+ encoder_attention_mask: Optional[torch.LongTensor] = None,
+ head_mask: Optional[torch.Tensor] = None,
+ cross_attn_head_mask: Optional[torch.Tensor] = None,
+ past_key_values: Optional[Tuple[Tuple[torch.FloatTensor]]] = None,
+ inputs_embeds: Optional[torch.FloatTensor] = None,
+ use_cache: Optional[bool] = None,
+ output_attentions: Optional[bool] = None,
+ output_hidden_states: Optional[bool] = None,
+ return_dict: Optional[bool] = None,
+ ) -> Union[Tuple, BaseModelOutputWithPastAndCrossAttentions]:
+ output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
+ output_hidden_states = (
+ output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
+ )
+ use_cache = use_cache if use_cache is not None else self.config.use_cache
+ return_dict = return_dict if return_dict is not None else self.config.use_return_dict
+
+ # retrieve input_ids and inputs_embeds
+ if input_ids is not None and inputs_embeds is not None:
+ raise ValueError("You cannot specify both decoder_input_ids and decoder_inputs_embeds at the same time")
+ elif input_ids is not None:
+ # (bsz * codebooks, seq_len) -> (bsz, codebooks, seq_len)
+ input = input_ids.reshape(-1, self.num_codebooks, input_ids.shape[-1])
+ bsz, num_codebooks, seq_len = input.shape
+ input_shape = (bsz, seq_len)
+ elif inputs_embeds is not None:
+ input_shape = inputs_embeds.size()[:-1]
+ input = inputs_embeds[:, :, -1:]
+ else:
+ raise ValueError("You have to specify either decoder_input_ids or decoder_inputs_embeds")
+
+ # past_key_values_length
+ past_key_values_length = past_key_values[0][0].shape[2] if past_key_values is not None else 0
+
+ if inputs_embeds is None:
+ inputs_embeds = sum([self.embed_tokens[codebook](input[:, codebook]) for codebook in range(num_codebooks)])
+
+ attention_mask = _prepare_4d_causal_attention_mask(
+ attention_mask, input_shape, inputs_embeds, past_key_values_length
+ )
+
+ # expand encoder attention mask
+ if encoder_hidden_states is not None and encoder_attention_mask is not None:
+ # [bsz, seq_len] -> [bsz, 1, tgt_seq_len, src_seq_len]
+ encoder_attention_mask = _prepare_4d_attention_mask(
+ encoder_attention_mask, inputs_embeds.dtype, tgt_len=input_shape[-1]
+ )
+
+ # embed positions
+ positions = self.embed_positions(input, past_key_values_length)
+
+ hidden_states = inputs_embeds + positions.to(inputs_embeds.device)
+
+ hidden_states = nn.functional.dropout(hidden_states, p=self.dropout, training=self.training)
+
+ if self.gradient_checkpointing and self.training:
+ if use_cache:
+ logger.warning_once(
+ "`use_cache=True` is incompatible with gradient checkpointing`. Setting `use_cache=False`..."
+ )
+ use_cache = False
+
+ # decoder layers
+ all_hidden_states = () if output_hidden_states else None
+ all_self_attns = () if output_attentions else None
+ all_cross_attentions = () if (output_attentions and encoder_hidden_states is not None) else None
+ next_decoder_cache = () if use_cache else None
+
+ # check if head_mask/cross_attn_head_mask has a correct number of layers specified if desired
+ for attn_mask, mask_name in zip([head_mask, cross_attn_head_mask], ["head_mask", "cross_attn_head_mask"]):
+ if attn_mask is not None:
+ if attn_mask.size()[0] != len(self.layers):
+ raise ValueError(
+ f"The `{mask_name}` should be specified for {len(self.layers)} layers, but it is for"
+ f" {attn_mask.size()[0]}."
+ )
+ for idx, decoder_layer in enumerate(self.layers):
+ # add LayerDrop (see https://arxiv.org/abs/1909.11556 for description)
+ if output_hidden_states:
+ all_hidden_states += (hidden_states,)
+ dropout_probability = random.uniform(0, 1)
+ if self.training and (dropout_probability < self.layerdrop):
+ continue
+
+ past_key_value = past_key_values[idx] if past_key_values is not None else None
+
+ if self.gradient_checkpointing and self.training:
+ layer_outputs = self._gradient_checkpointing_func(
+ decoder_layer.forward,
+ hidden_states,
+ attention_mask,
+ encoder_hidden_states,
+ encoder_attention_mask,
+ head_mask[idx] if head_mask is not None else None,
+ cross_attn_head_mask[idx] if cross_attn_head_mask is not None else None,
+ None,
+ output_attentions,
+ use_cache,
+ )
+ else:
+ layer_outputs = decoder_layer(
+ hidden_states,
+ attention_mask=attention_mask,
+ encoder_hidden_states=encoder_hidden_states,
+ encoder_attention_mask=encoder_attention_mask,
+ layer_head_mask=(head_mask[idx] if head_mask is not None else None),
+ cross_attn_layer_head_mask=(
+ cross_attn_head_mask[idx] if cross_attn_head_mask is not None else None
+ ),
+ past_key_value=past_key_value,
+ output_attentions=output_attentions,
+ use_cache=use_cache,
+ )
+ hidden_states = layer_outputs[0]
+
+ if use_cache:
+ next_decoder_cache += (layer_outputs[3 if output_attentions else 1],)
+
+ if output_attentions:
+ all_self_attns += (layer_outputs[1],)
+
+ if encoder_hidden_states is not None:
+ all_cross_attentions += (layer_outputs[2],)
+
+ hidden_states = self.layer_norm(hidden_states)
+
+ # add hidden states from the last decoder layer
+ if output_hidden_states:
+ all_hidden_states += (hidden_states,)
+
+ next_cache = next_decoder_cache if use_cache else None
+ if not return_dict:
+ return tuple(
+ v
+ for v in [hidden_states, next_cache, all_hidden_states, all_self_attns, all_cross_attentions]
+ if v is not None
+ )
+ return BaseModelOutputWithPastAndCrossAttentions(
+ last_hidden_state=hidden_states,
+ past_key_values=next_cache,
+ hidden_states=all_hidden_states,
+ attentions=all_self_attns,
+ cross_attentions=all_cross_attentions,
+ )
+
+
+@add_start_docstrings(
+ "The bare Musicgen decoder model outputting raw hidden-states without any specific head on top.",
+ MUSICGEN_START_DOCSTRING,
+)
+class MusicgenModel(MusicgenPreTrainedModel):
+ def __init__(self, config: MusicgenDecoderConfig):
+ super().__init__(config)
+ self.decoder = MusicgenDecoder(config)
+ # Initialize weights and apply final processing
+ self.post_init()
+
+ def get_input_embeddings(self):
+ return self.decoder.embed_tokens
+
+ def set_input_embeddings(self, value):
+ self.decoder.embed_tokens = value
+
+ def get_decoder(self):
+ return self.decoder
+
+ @add_start_docstrings_to_model_forward(MUSICGEN_DECODER_INPUTS_DOCSTRING)
+ def forward(
+ self,
+ input_ids: torch.LongTensor = None,
+ attention_mask: Optional[torch.Tensor] = None,
+ encoder_hidden_states: Optional[torch.FloatTensor] = None,
+ encoder_attention_mask: Optional[torch.LongTensor] = None,
+ head_mask: Optional[torch.Tensor] = None,
+ cross_attn_head_mask: Optional[torch.Tensor] = None,
+ past_key_values: Optional[Tuple[Tuple[torch.FloatTensor]]] = None,
+ inputs_embeds: Optional[torch.FloatTensor] = None,
+ use_cache: Optional[bool] = None,
+ output_attentions: Optional[bool] = None,
+ output_hidden_states: Optional[bool] = None,
+ return_dict: Optional[bool] = None,
+ ) -> Union[Tuple, BaseModelOutputWithPastAndCrossAttentions]:
+ output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
+ output_hidden_states = (
+ output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
+ )
+ use_cache = use_cache if use_cache is not None else self.config.use_cache
+ return_dict = return_dict if return_dict is not None else self.config.use_return_dict
+
+ # decoder outputs consists of (dec_features, past_key_value, dec_hidden, dec_attn)
+ decoder_outputs = self.decoder(
+ input_ids=input_ids,
+ attention_mask=attention_mask,
+ encoder_attention_mask=encoder_attention_mask,
+ encoder_hidden_states=encoder_hidden_states,
+ head_mask=head_mask,
+ cross_attn_head_mask=cross_attn_head_mask,
+ past_key_values=past_key_values,
+ inputs_embeds=inputs_embeds,
+ use_cache=use_cache,
+ output_attentions=output_attentions,
+ output_hidden_states=output_hidden_states,
+ return_dict=return_dict,
+ )
+
+ if not return_dict:
+ return decoder_outputs
+
+ return BaseModelOutputWithPastAndCrossAttentions(
+ last_hidden_state=decoder_outputs.last_hidden_state,
+ past_key_values=decoder_outputs.past_key_values,
+ hidden_states=decoder_outputs.hidden_states,
+ attentions=decoder_outputs.attentions,
+ cross_attentions=decoder_outputs.cross_attentions,
+ )
+
+
+@add_start_docstrings(
+ "The MusicGen decoder model with a language modelling head on top.",
+ MUSICGEN_START_DOCSTRING,
+)
+class MusicgenForCausalLM(MusicgenPreTrainedModel):
+ def __init__(self, config: MusicgenDecoderConfig):
+ super().__init__(config)
+
+ self.model = MusicgenModel(config)
+
+ self.num_codebooks = config.num_codebooks
+ self.lm_heads = nn.ModuleList(
+ [nn.Linear(config.hidden_size, config.vocab_size, bias=False) for _ in range(config.num_codebooks)]
+ )
+
+ # Initialize weights and apply final processing
+ self.post_init()
+
+ def get_input_embeddings(self):
+ return self.model.decoder.embed_tokens
+
+ def set_input_embeddings(self, value):
+ self.model.decoder.embed_tokens = value
+
+ def get_output_embeddings(self):
+ return self.lm_heads
+
+ def set_output_embeddings(self, new_embeddings):
+ self.lm_heads = new_embeddings
+
+ def set_decoder(self, decoder):
+ self.model.decoder = decoder
+
+ def get_decoder(self):
+ return self.model.decoder
+
+ @add_start_docstrings_to_model_forward(MUSICGEN_DECODER_INPUTS_DOCSTRING)
+ @replace_return_docstrings(output_type=Seq2SeqLMOutput, config_class=_CONFIG_FOR_DOC)
+ def forward(
+ self,
+ input_ids: torch.LongTensor = None,
+ attention_mask: Optional[torch.Tensor] = None,
+ encoder_hidden_states: Optional[torch.FloatTensor] = None,
+ encoder_attention_mask: Optional[torch.LongTensor] = None,
+ head_mask: Optional[torch.Tensor] = None,
+ cross_attn_head_mask: Optional[torch.Tensor] = None,
+ past_key_values: Optional[Tuple[Tuple[torch.FloatTensor]]] = None,
+ inputs_embeds: Optional[torch.FloatTensor] = None,
+ labels: Optional[torch.LongTensor] = None,
+ use_cache: Optional[bool] = None,
+ output_attentions: Optional[bool] = None,
+ output_hidden_states: Optional[bool] = None,
+ return_dict: Optional[bool] = None,
+ ) -> Union[Tuple, CausalLMOutputWithCrossAttentions]:
+ r"""
+ labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
+ Labels for language modeling. Note that the labels **are shifted** inside the model, i.e. you can set
+ `labels = input_ids` Indices are selected in `[-100, 0, ..., config.vocab_size]` All labels set to `-100`
+ are ignored (masked), the loss is only computed for labels in `[0, ..., config.vocab_size]`
+ Returns:
+ """
+
+ return_dict = return_dict if return_dict is not None else self.config.use_return_dict
+
+ outputs = self.model(
+ input_ids,
+ attention_mask=attention_mask,
+ encoder_hidden_states=encoder_hidden_states,
+ encoder_attention_mask=encoder_attention_mask,
+ head_mask=head_mask,
+ cross_attn_head_mask=cross_attn_head_mask,
+ past_key_values=past_key_values,
+ inputs_embeds=inputs_embeds,
+ use_cache=use_cache,
+ output_attentions=output_attentions,
+ output_hidden_states=output_hidden_states,
+ return_dict=return_dict,
+ )
+
+ hidden_states = outputs[0]
+
+ lm_logits = torch.stack([head(hidden_states) for head in self.lm_heads], dim=1)
+
+ loss = None
+ if labels is not None:
+ raise NotImplementedError("Training is not implemented for Musicgen.")
+
+ # (bsz, num_codebooks, seq_len, vocab_size) -> (bsz * num_codebooks, seq_len, vocab_size)
+ lm_logits = lm_logits.reshape(-1, *lm_logits.shape[2:])
+
+ if not return_dict:
+ output = (lm_logits,) + outputs[1:]
+ return ((loss,) + output) if loss is not None else output
+
+ return CausalLMOutputWithCrossAttentions(
+ loss=loss,
+ logits=lm_logits,
+ past_key_values=outputs.past_key_values,
+ hidden_states=outputs.hidden_states,
+ attentions=outputs.attentions,
+ cross_attentions=outputs.cross_attentions,
+ )
+
+ def prepare_inputs_for_generation(
+ self,
+ input_ids,
+ attention_mask=None,
+ encoder_hidden_states=None,
+ encoder_attention_mask=None,
+ head_mask=None,
+ cross_attn_head_mask=None,
+ past_key_values=None,
+ use_cache=True,
+ delay_pattern_mask=None,
+ guidance_scale=None,
+ **kwargs,
+ ):
+ if delay_pattern_mask is None:
+ input_ids, delay_pattern_mask = self.build_delay_pattern_mask(
+ input_ids,
+ pad_token_id=self.generation_config.pad_token_id,
+ max_length=self.generation_config.max_length,
+ )
+
+ # apply the delay pattern mask
+ input_ids = self.apply_delay_pattern_mask(input_ids, delay_pattern_mask)
+
+ if guidance_scale is not None and guidance_scale > 1:
+ # for classifier free guidance we need to replicate the decoder args across the batch dim (we'll split these
+ # before sampling)
+ input_ids = input_ids.repeat((2, 1))
+ if attention_mask is not None:
+ attention_mask = attention_mask.repeat((2, 1))
+
+ if past_key_values is not None:
+ input_ids = input_ids[:, -1:]
+
+ return {
+ "input_ids": input_ids,
+ "attention_mask": attention_mask,
+ "encoder_hidden_states": encoder_hidden_states,
+ "encoder_attention_mask": encoder_attention_mask,
+ "head_mask": head_mask,
+ "cross_attn_head_mask": cross_attn_head_mask,
+ "past_key_values": past_key_values,
+ "use_cache": use_cache,
+ }
+
+ def build_delay_pattern_mask(self, input_ids: torch.LongTensor, pad_token_id: int, max_length: int = None):
+ """Build a delayed pattern mask to the input_ids. Each codebook is offset by the previous codebook by
+ one, giving a delayed pattern mask at the start of sequence and end of sequence. Take the example where there
+ are 4 codebooks and a max sequence length of 8, we have the delayed pattern mask of shape `(codebooks,
+ seq_len)`:
+ - [P, -1, -1, -1, -1, P, P, P]
+ - [P, P, -1, -1, -1, -1, P, P]
+ - [P, P, P, -1, -1, -1, -1, P]
+ - [P, P, P, P, -1, -1, -1, -1]
+ where P is the special padding token id and -1 indicates that the token is valid for prediction. If we include
+ a prompt (decoder input ids), the -1 positions indicate where new tokens should be predicted. Otherwise, the
+ mask is set to the value in the prompt:
+ - [P, a, b, -1, -1, P, P, P]
+ - [P, P, c, d, -1, -1, P, P]
+ - [P, P, P, e, f, -1, -1, P]
+ - [P, P, P, P, g, h, -1, -1]
+ where a-h indicate the input prompt (decoder input ids) that are offset by 1. Now, we only override the -1
+ tokens in our prediction.
+ """
+ # (bsz * num_codebooks, seq_len) -> (bsz, num_codebooks, seq_len)
+ input_ids = input_ids.reshape(-1, self.num_codebooks, input_ids.shape[-1])
+ bsz, num_codebooks, seq_len = input_ids.shape
+
+ max_length = max_length if max_length is not None else self.generation_config.max_length
+ input_ids_shifted = (
+ torch.ones((bsz, num_codebooks, max_length), dtype=torch.long, device=input_ids.device) * -1
+ )
+
+ # we only apply the mask if we have a large enough seq len - otherwise we return as is
+ if max_length < 2 * num_codebooks - 1:
+ return input_ids.reshape(bsz * num_codebooks, -1), input_ids_shifted.reshape(bsz * num_codebooks, -1)
+
+ # fill the shifted ids with the prompt entries, offset by the codebook idx
+ for codebook in range(num_codebooks):
+ input_ids_shifted[:, codebook, codebook : seq_len + codebook] = input_ids[:, codebook]
+
+ # construct a pattern mask that indicates the positions of padding tokens for each codebook
+ # first fill the upper triangular part (the EOS padding)
+ delay_pattern = torch.triu(
+ torch.ones((num_codebooks, max_length), dtype=torch.bool), diagonal=max_length - num_codebooks + 1
+ )
+ # then fill the lower triangular part (the BOS padding)
+ delay_pattern = delay_pattern + torch.tril(torch.ones((num_codebooks, max_length), dtype=torch.bool))
+ mask = ~delay_pattern.to(input_ids.device)
+ input_ids = mask * input_ids_shifted + ~mask * pad_token_id
+
+ # find the first position to start generating - this is the first place we have the -1 token
+ # and will always be in the first codebook (since it has no codebook offset)
+ first_codebook_ids = input_ids[:, 0, :]
+ start_ids = (first_codebook_ids == -1).nonzero()[:, 1]
+ if len(start_ids) > 0:
+ first_start_id = min(start_ids)
+ else:
+ # we have no tokens that need to be filled - return entire matrix of input ids
+ first_start_id = seq_len
+
+ # (bsz * num_codebooks, seq_len) -> (bsz, num_codebooks, seq_len)
+ pattern_mask = input_ids.reshape(bsz * num_codebooks, -1)
+ input_ids = input_ids[..., :first_start_id].reshape(bsz * num_codebooks, -1)
+ return input_ids, pattern_mask
+
+ @staticmethod
+ def apply_delay_pattern_mask(input_ids, decoder_pad_token_mask):
+ """Apply a delay pattern mask to the decoder input ids, only preserving predictions where
+ the mask is set to -1, and otherwise setting to the value detailed in the mask."""
+ seq_len = input_ids.shape[-1]
+ decoder_pad_token_mask = decoder_pad_token_mask[..., :seq_len]
+ input_ids = torch.where(decoder_pad_token_mask == -1, input_ids, decoder_pad_token_mask)
+ return input_ids
+
+ @torch.no_grad()
+ def generate(
+ self,
+ inputs: Optional[torch.Tensor] = None,
+ generation_config: Optional[GenerationConfig] = None,
+ logits_processor: Optional[LogitsProcessorList] = None,
+ stopping_criteria: Optional[StoppingCriteriaList] = None,
+ synced_gpus: Optional[bool] = None,
+ streamer: Optional["BaseStreamer"] = None,
+ **kwargs,
+ ):
+ """
+
+ Generates sequences of token ids for models with a language modeling head.
+
+
+
+ Most generation-controlling parameters are set in `generation_config` which, if not passed, will be set to the
+ model's default generation configuration. You can override any `generation_config` by passing the corresponding
+ parameters to generate(), e.g. `.generate(inputs, num_beams=4, do_sample=True)`.
+
+ For an overview of generation strategies and code examples, check out the [following
+ guide](./generation_strategies).
+
+
+
+ Parameters:
+ inputs (`torch.Tensor` of varying shape depending on the modality, *optional*):
+ The sequence used as a prompt for the generation or as model inputs to the encoder. If `None` the
+ method initializes it with `bos_token_id` and a batch size of 1. For decoder-only models `inputs`
+ should be in the format `input_ids`. For encoder-decoder models *inputs* can represent any of
+ `input_ids`, `input_values`, `input_features`, or `pixel_values`.
+ generation_config (`~generation.GenerationConfig`, *optional*):
+ The generation configuration to be used as base parametrization for the generation call. `**kwargs`
+ passed to generate matching the attributes of `generation_config` will override them. If
+ `generation_config` is not provided, the default will be used, which had the following loading
+ priority: 1) from the `generation_config.json` model file, if it exists; 2) from the model
+ configuration. Please note that unspecified parameters will inherit [`~generation.GenerationConfig`]'s
+ default values, whose documentation should be checked to parameterize generation.
+ logits_processor (`LogitsProcessorList`, *optional*):
+ Custom logits processors that complement the default logits processors built from arguments and
+ generation config. If a logit processor is passed that is already created with the arguments or a
+ generation config an error is thrown. This feature is intended for advanced users.
+ stopping_criteria (`StoppingCriteriaList`, *optional*):
+ Custom stopping criteria that complement the default stopping criteria built from arguments and a
+ generation config. If a stopping criteria is passed that is already created with the arguments or a
+ generation config an error is thrown. This feature is intended for advanced users.
+ synced_gpus (`bool`, *optional*, defaults to `False`):
+ Whether to continue running the while loop until max_length (needed for ZeRO stage 3)
+ streamer (`BaseStreamer`, *optional*):
+ Streamer object that will be used to stream the generated sequences. Generated tokens are passed
+ through `streamer.put(token_ids)` and the streamer is responsible for any further processing.
+ kwargs (`Dict[str, Any]`, *optional*):
+ Ad hoc parametrization of `generate_config` and/or additional model-specific kwargs that will be
+ forwarded to the `forward` function of the model. If the model is an encoder-decoder model, encoder
+ specific kwargs should not be prefixed and decoder specific kwargs should be prefixed with *decoder_*.
+
+ Return:
+ [`~utils.ModelOutput`] or `torch.LongTensor`: A [`~utils.ModelOutput`] (if `return_dict_in_generate=True`
+ or when `config.return_dict_in_generate=True`) or a `torch.FloatTensor`.
+
+ If the model is *not* an encoder-decoder model (`model.config.is_encoder_decoder=False`), the possible
+ [`~utils.ModelOutput`] types are:
+
+ - [`~generation.GreedySearchDecoderOnlyOutput`],
+ - [`~generation.SampleDecoderOnlyOutput`],
+ - [`~generation.BeamSearchDecoderOnlyOutput`],
+ - [`~generation.BeamSampleDecoderOnlyOutput`]
+
+ If the model is an encoder-decoder model (`model.config.is_encoder_decoder=True`), the possible
+ [`~utils.ModelOutput`] types are:
+
+ - [`~generation.GreedySearchEncoderDecoderOutput`],
+ - [`~generation.SampleEncoderDecoderOutput`],
+ - [`~generation.BeamSearchEncoderDecoderOutput`],
+ - [`~generation.BeamSampleEncoderDecoderOutput`]
+ """
+ # 1. Handle `generation_config` and kwargs that might update it, and validate the resulting objects
+ if generation_config is None:
+ generation_config = self.generation_config
+
+ generation_config = copy.deepcopy(generation_config)
+ model_kwargs = generation_config.update(**kwargs) # All unused kwargs must be model kwargs
+ generation_config.validate()
+ self._validate_model_kwargs(model_kwargs.copy())
+
+ # 2. Set generation parameters if not already defined
+ logits_processor = logits_processor if logits_processor is not None else LogitsProcessorList()
+ stopping_criteria = stopping_criteria if stopping_criteria is not None else StoppingCriteriaList()
+
+ if generation_config.pad_token_id is None and generation_config.eos_token_id is not None:
+ if model_kwargs.get("attention_mask", None) is None:
+ logger.warning(
+ "The attention mask and the pad token id were not set. As a consequence, you may observe "
+ "unexpected behavior. Please pass your input's `attention_mask` to obtain reliable results."
+ )
+ eos_token_id = generation_config.eos_token_id
+ if isinstance(eos_token_id, list):
+ eos_token_id = eos_token_id[0]
+ logger.warning(f"Setting `pad_token_id` to `eos_token_id`:{eos_token_id} for open-end generation.")
+ generation_config.pad_token_id = eos_token_id
+
+ # 3. Define model inputs
+ # inputs_tensor has to be defined
+ # model_input_name is defined if model-specific keyword input is passed
+ # otherwise model_input_name is None
+ # all model-specific keyword inputs are removed from `model_kwargs`
+ input_ids, model_input_name, model_kwargs = self._prepare_model_inputs(
+ inputs, generation_config.bos_token_id, model_kwargs
+ )
+ batch_size = input_ids.shape[0] // self.num_codebooks
+
+ # 4. Define other model kwargs
+ model_kwargs["output_attentions"] = generation_config.output_attentions
+ model_kwargs["output_hidden_states"] = generation_config.output_hidden_states
+ model_kwargs["use_cache"] = generation_config.use_cache
+ model_kwargs["guidance_scale"] = generation_config.guidance_scale
+
+ requires_attention_mask = "encoder_outputs" not in model_kwargs
+ if model_kwargs.get("attention_mask", None) is None and requires_attention_mask:
+ model_kwargs["attention_mask"] = self._prepare_attention_mask_for_generation(
+ input_ids, generation_config.pad_token_id, generation_config.eos_token_id
+ )
+
+ # 5. Prepare `max_length` depending on other stopping criteria.
+ input_ids_seq_length = input_ids.shape[-1]
+ has_default_max_length = kwargs.get("max_length") is None and generation_config.max_length is not None
+ if has_default_max_length and generation_config.max_new_tokens is None and generation_config.max_length == 20:
+ logger.warning(
+ f"Using the model-agnostic default `max_length` (={generation_config.max_length}) "
+ "to control the generation length. recommend setting `max_new_tokens` to control the maximum length of the generation."
+ )
+ elif generation_config.max_new_tokens is not None:
+ if not has_default_max_length:
+ logger.warning(
+ f"Both `max_new_tokens` (={generation_config.max_new_tokens}) and `max_length`(="
+ f"{generation_config.max_length}) seem to have been set. `max_new_tokens` will take precedence. "
+ "Please refer to the documentation for more information. "
+ "(https://huggingface.co/docs/transformers/main/en/main_classes/text_generation)"
+ )
+ generation_config.max_length = generation_config.max_new_tokens + input_ids_seq_length
+
+ if generation_config.min_length is not None and generation_config.min_length > generation_config.max_length:
+ raise ValueError(
+ f"Unfeasible length constraints: the minimum length ({generation_config.min_length}) is larger than"
+ f" the maximum length ({generation_config.max_length})"
+ )
+ if input_ids_seq_length >= generation_config.max_length:
+ logger.warning(
+ f"Input length of decoder_input_ids is {input_ids_seq_length}, but `max_length` is set to"
+ f" {generation_config.max_length}. This can lead to unexpected behavior. You should consider"
+ " increasing `max_new_tokens`."
+ )
+
+ # 6. Prepare `input_ids` which will be used for auto-regressive generation
+ # Build the delay pattern mask for offsetting each codebook prediction by 1 (this behaviour is specific to MusicGen)
+ input_ids, delay_pattern_mask = self.build_delay_pattern_mask(
+ input_ids,
+ pad_token_id=generation_config.decoder_start_token_id,
+ max_length=generation_config.max_length,
+ )
+
+ if streamer is not None:
+ streamer.put(input_ids.cpu())
+
+ # stash the delay mask so that we don't have to recompute it in each forward pass
+ model_kwargs["delay_pattern_mask"] = delay_pattern_mask
+
+ # 7. determine generation mode
+ is_greedy_gen_mode = (
+ (generation_config.num_beams == 1)
+ and (generation_config.num_beam_groups == 1)
+ and generation_config.do_sample is False
+ )
+ is_sample_gen_mode = (
+ (generation_config.num_beams == 1)
+ and (generation_config.num_beam_groups == 1)
+ and generation_config.do_sample is True
+ )
+
+ # 8. prepare batched CFG externally (to enable coexistance with the unbatched CFG)
+ if generation_config.guidance_scale is not None and generation_config.guidance_scale > 1:
+ logits_processor.append(ClassifierFreeGuidanceLogitsProcessor(generation_config.guidance_scale))
+ generation_config.guidance_scale = None
+
+ # 9. prepare distribution pre_processing samplers
+ logits_processor = self._get_logits_processor(
+ generation_config=generation_config,
+ input_ids_seq_length=input_ids_seq_length,
+ encoder_input_ids=input_ids,
+ prefix_allowed_tokens_fn=None,
+ logits_processor=logits_processor,
+ )
+
+ # 10. prepare stopping criteria
+ stopping_criteria = self._get_stopping_criteria(
+ generation_config=generation_config, stopping_criteria=stopping_criteria
+ )
+
+ if is_greedy_gen_mode:
+ if generation_config.num_return_sequences > 1:
+ raise ValueError(
+ "num_return_sequences has to be 1 when doing greedy search, "
+ f"but is {generation_config.num_return_sequences}."
+ )
+
+ # 11. run greedy search
+ outputs = self.greedy_search(
+ input_ids,
+ logits_processor=logits_processor,
+ stopping_criteria=stopping_criteria,
+ pad_token_id=generation_config.pad_token_id,
+ eos_token_id=generation_config.eos_token_id,
+ output_scores=generation_config.output_scores,
+ return_dict_in_generate=generation_config.return_dict_in_generate,
+ synced_gpus=synced_gpus,
+ streamer=streamer,
+ **model_kwargs,
+ )
+
+ elif is_sample_gen_mode:
+ # 11. prepare logits warper
+ logits_warper = self._get_logits_warper(generation_config)
+
+ # expand input_ids with `num_return_sequences` additional sequences per batch
+ input_ids, model_kwargs = self._expand_inputs_for_generation(
+ input_ids=input_ids,
+ expand_size=generation_config.num_return_sequences,
+ **model_kwargs,
+ )
+
+ # 12. run sample
+ outputs = self.sample(
+ input_ids,
+ logits_processor=logits_processor,
+ logits_warper=logits_warper,
+ stopping_criteria=stopping_criteria,
+ pad_token_id=generation_config.pad_token_id,
+ eos_token_id=generation_config.eos_token_id,
+ output_scores=generation_config.output_scores,
+ return_dict_in_generate=generation_config.return_dict_in_generate,
+ synced_gpus=synced_gpus,
+ streamer=streamer,
+ **model_kwargs,
+ )
+
+ else:
+ raise ValueError(
+ "Got incompatible mode for generation, should be one of greedy or sampling. "
+ "Ensure that beam search is de-activated by setting `num_beams=1` and `num_beam_groups=1`."
+ )
+
+ if generation_config.return_dict_in_generate:
+ output_ids = outputs.sequences
+ else:
+ output_ids = outputs
+
+ # apply the pattern mask to the final ids
+ output_ids = self.apply_delay_pattern_mask(output_ids, model_kwargs["delay_pattern_mask"])
+
+ # revert the pattern delay mask by filtering the pad token id
+ output_ids = output_ids[output_ids != generation_config.pad_token_id].reshape(
+ batch_size, self.num_codebooks, -1
+ )
+
+ if generation_config.return_dict_in_generate:
+ outputs.sequences = output_ids
+ return outputs
+ else:
+ return output_ids
+
+
+@add_start_docstrings(
+ "The composite MusicGen model with a text encoder, audio encoder and Musicgen decoder, "
+ "for music generation tasks with one or both of text and audio prompts.",
+ MUSICGEN_START_DOCSTRING,
+)
+class MusicgenForConditionalGeneration(PreTrainedModel):
+ config_class = MusicgenConfig
+ base_model_prefix = "encoder_decoder"
+ main_input_name = "input_ids"
+ supports_gradient_checkpointing = True
+
+ def __init__(
+ self,
+ config: Optional[MusicgenConfig] = None,
+ text_encoder: Optional[PreTrainedModel] = None,
+ audio_encoder: Optional[PreTrainedModel] = None,
+ decoder: Optional[MusicgenForCausalLM] = None,
+ ):
+ if config is None and (text_encoder is None or audio_encoder is None or decoder is None):
+ raise ValueError(
+ "Either a configuration has to be provided, or all three of text encoder, audio encoder and MusicGen decoder."
+ )
+ if config is None:
+ config = MusicgenConfig.from_sub_models_config(text_encoder.config, audio_encoder.config, decoder.config)
+ else:
+ if not isinstance(config, self.config_class):
+ raise ValueError(f"Config: {config} has to be of type {self.config_class}")
+
+ if config.decoder.cross_attention_hidden_size is not None:
+ if config.decoder.cross_attention_hidden_size != config.text_encoder.hidden_size:
+ raise ValueError(
+ "If `cross_attention_hidden_size` is specified in the MusicGen decoder's configuration, it has to be equal"
+ f" to the text encoder's `hidden_size`. Got {config.decoder.cross_attention_hidden_size} for"
+ f" `config.decoder.cross_attention_hidden_size` and {config.text_encoder.hidden_size} for"
+ " `config.text_encoder.hidden_size`."
+ )
+
+ # initialize with config
+ super().__init__(config)
+
+ if text_encoder is None:
+ from transformers.models.auto.modeling_auto import AutoModelForTextEncoding
+
+ text_encoder = AutoModelForTextEncoding.from_config(config.text_encoder)
+
+ if audio_encoder is None:
+ from transformers.models.auto.modeling_auto import AutoModel
+
+ audio_encoder = AutoModel.from_config(config.audio_encoder)
+
+ if decoder is None:
+ decoder = MusicgenForCausalLM(config.decoder)
+
+ self.text_encoder = text_encoder
+ self.audio_encoder = audio_encoder
+ self.decoder = decoder
+
+ if self.text_encoder.config.to_dict() != self.config.text_encoder.to_dict():
+ logger.warning(
+ f"Config of the text_encoder: {self.text_encoder.__class__} is overwritten by shared text_encoder config:"
+ f" {self.config.text_encoder}"
+ )
+ if self.audio_encoder.config.to_dict() != self.config.audio_encoder.to_dict():
+ logger.warning(
+ f"Config of the audio_encoder: {self.audio_encoder.__class__} is overwritten by shared audio_encoder config:"
+ f" {self.config.audio_encoder}"
+ )
+ if self.decoder.config.to_dict() != self.config.decoder.to_dict():
+ logger.warning(
+ f"Config of the decoder: {self.decoder.__class__} is overwritten by shared decoder config:"
+ f" {self.config.decoder}"
+ )
+
+ # make sure that the individual model's config refers to the shared config
+ # so that the updates to the config will be synced
+ self.text_encoder.config = self.config.text_encoder
+ self.audio_encoder.config = self.config.audio_encoder
+ self.decoder.config = self.config.decoder
+
+ # text encoder outputs might need to be projected to different dimension for decoder
+ if (
+ self.text_encoder.config.hidden_size != self.decoder.config.hidden_size
+ and self.decoder.config.cross_attention_hidden_size is None
+ ):
+ self.enc_to_dec_proj = nn.Linear(self.text_encoder.config.hidden_size, self.decoder.config.hidden_size)
+
+ if self.text_encoder.get_output_embeddings() is not None:
+ raise ValueError(
+ f"The encoder {self.text_encoder} should not have a LM Head. Please use a model without and LM Head"
+ )
+
+ decoder_signature = set(inspect.signature(self.decoder.forward).parameters.keys())
+ if "encoder_hidden_states" not in decoder_signature:
+ raise ValueError(
+ "The selected decoder is not prepared for the encoder hidden states to be passed. Please see the "
+ "following discussion on GitHub: https://github.com/huggingface/transformers/issues/23350"
+ )
+
+ # tie text encoder, decoder weights if config set accordingly
+ self.tie_weights()
+
+ def tie_weights(self):
+ # tie text encoder & decoder if needed
+ if self.config.tie_encoder_decoder:
+ # tie text encoder and decoder base model
+ decoder_base_model_prefix = self.decoder.base_model_prefix
+ self._tie_encoder_decoder_weights(
+ self.text_encoder, self.decoder._modules[decoder_base_model_prefix], self.decoder.base_model_prefix
+ )
+
+ def get_audio_encoder(self):
+ return self.audio_encoder
+
+ def get_text_encoder(self):
+ return self.text_encoder
+
+ def get_encoder(self):
+ # get the text encoder to compute the encoder hidden-states for generation
+ return self.get_text_encoder()
+
+ def get_decoder(self):
+ return self.decoder
+
+ def get_input_embeddings(self):
+ return self.text_encoder.get_input_embeddings()
+
+ def get_output_embeddings(self):
+ return self.decoder.get_output_embeddings()
+
+ def set_output_embeddings(self, new_embeddings):
+ return self.decoder.set_output_embeddings(new_embeddings)
+
+ @classmethod
+ def from_pretrained(cls, pretrained_model_name_or_path, *model_args, **kwargs):
+ r"""
+ Example:
+
+ ```python
+ >>> from transformers import MusicgenForConditionalGeneration
+
+ >>> model = MusicgenForConditionalGeneration.from_pretrained("facebook/musicgen-small")
+ ```"""
+
+ # At the moment fast initialization is not supported for composite models
+ if kwargs.get("_fast_init", False):
+ logger.warning(
+ "Fast initialization is currently not supported for MusicgenForConditionalGeneration. "
+ "Falling back to slow initialization..."
+ )
+ kwargs["_fast_init"] = False
+
+ return super().from_pretrained(pretrained_model_name_or_path, *model_args, **kwargs)
+
+ @classmethod
+ def from_sub_models_pretrained(
+ cls,
+ text_encoder_pretrained_model_name_or_path: str = None,
+ audio_encoder_pretrained_model_name_or_path: str = None,
+ decoder_pretrained_model_name_or_path: str = None,
+ *model_args,
+ **kwargs,
+ ) -> PreTrainedModel:
+ r"""
+ Instantiate a text encoder, an audio encoder, and a MusicGen decoder from one, two or three base classes of the
+ library from pretrained model checkpoints.
+
+
+ The model is set in evaluation mode by default using `model.eval()` (Dropout modules are deactivated). To train
+ the model, you need to first set it back in training mode with `model.train()`.
+
+ Params:
+ text_encoder_pretrained_model_name_or_path (`str`, *optional*):
+ Information necessary to initiate the text encoder. Can be either:
+
+ - A string, the *model id* of a pretrained model hosted inside a model repo on huggingface.co.
+ Valid model ids can be located at the root-level, like `t5-base`, or namespaced under a user or
+ organization name, like `google/flan-t5-base.
+ - A path to a *directory* containing model weights saved using
+ [`~PreTrainedModel.save_pretrained`], e.g., `./my_model_directory/`.
+
+ audio_encoder_pretrained_model_name_or_path (`str`, *optional*):
+ Information necessary to initiate the audio encoder. Can be either:
+
+ - A string, the *model id* of a pretrained model hosted inside a model repo on huggingface.co.
+ Valid model ids can be located at the root-level, like `bert-base-uncased`, or namespaced under a
+ user or organization name, like `facebook/encodec_24khz`.
+ - A path to a *directory* containing model weights saved using
+ [`~PreTrainedModel.save_pretrained`], e.g., `./my_model_directory/`.
+
+ decoder_pretrained_model_name_or_path (`str`, *optional*, defaults to `None`):
+ Information necessary to initiate the decoder. Can be either:
+
+ - A string, the *model id* of a pretrained model hosted inside a model repo on huggingface.co.
+ Valid model ids can be located at the root-level, like `gpt2`, or namespaced under a user or
+ organization name, like `facebook/musicgen-small`.
+ - A path to a *directory* containing model weights saved using
+ [`~PreTrainedModel.save_pretrained`], e.g., `./my_model_directory/`.
+
+ model_args (remaining positional arguments, *optional*):
+ All remaining positional arguments will be passed to the underlying model's `__init__` method.
+
+ kwargs (remaining dictionary of keyword arguments, *optional*):
+ Can be used to update the configuration object (after it being loaded) and initiate the model (e.g.,
+ `output_attentions=True`).
+
+ - To update the text encoder configuration, use the prefix *text_encoder_* for each configuration
+ parameter.
+ - To update the audio encoder configuration, use the prefix *audio_encoder_* for each configuration
+ parameter.
+ - To update the decoder configuration, use the prefix *decoder_* for each configuration parameter.
+ - To update the parent model configuration, do not use a prefix for each configuration parameter.
+
+ Behaves differently depending on whether a `config` is provided or automatically loaded.
+
+ Example:
+
+ ```python
+ >>> from transformers import MusicgenForConditionalGeneration
+
+ >>> # initialize a musicgen model from a t5 text encoder, encodec audio encoder, and musicgen decoder
+ >>> model = MusicgenForConditionalGeneration.from_sub_models_pretrained(
+ ... text_encoder_pretrained_model_name_or_path="t5-base",
+ ... audio_encoder_pretrained_model_name_or_path="facebook/encodec_24khz",
+ ... decoder_pretrained_model_name_or_path="facebook/musicgen-small",
+ ... )
+ >>> # saving model after fine-tuning
+ >>> model.save_pretrained("./musicgen-ft")
+ >>> # load fine-tuned model
+ >>> model = MusicgenForConditionalGeneration.from_pretrained("./musicgen-ft")
+ ```"""
+
+ kwargs_text_encoder = {
+ argument[len("text_encoder_") :]: value
+ for argument, value in kwargs.items()
+ if argument.startswith("text_encoder_")
+ }
+
+ kwargs_audio_encoder = {
+ argument[len("audio_encoder_") :]: value
+ for argument, value in kwargs.items()
+ if argument.startswith("audio_encoder_")
+ }
+
+ kwargs_decoder = {
+ argument[len("decoder_") :]: value for argument, value in kwargs.items() if argument.startswith("decoder_")
+ }
+
+ # remove text encoder, audio encoder and decoder kwargs from kwargs
+ for key in kwargs_text_encoder.keys():
+ del kwargs["text_encoder_" + key]
+ for key in kwargs_audio_encoder.keys():
+ del kwargs["audio_encoder_" + key]
+ for key in kwargs_decoder.keys():
+ del kwargs["decoder_" + key]
+
+ # Load and initialize the encoder and decoder
+ # The distinction between encoder and decoder at the model level is made
+ # by the value of the flag `is_decoder` that we need to set correctly.
+ text_encoder = kwargs_text_encoder.pop("model", None)
+ if text_encoder is None:
+ if text_encoder_pretrained_model_name_or_path is None:
+ raise ValueError(
+ "If `text_encoder_model` is not defined as an argument, a `text_encoder_pretrained_model_name_or_path` has "
+ "to be defined."
+ )
+
+ if "config" not in kwargs_text_encoder:
+ encoder_config, kwargs_text_encoder = AutoConfig.from_pretrained(
+ text_encoder_pretrained_model_name_or_path, **kwargs_text_encoder, return_unused_kwargs=True
+ )
+
+ if encoder_config.is_decoder is True or encoder_config.add_cross_attention is True:
+ logger.info(
+ f"Initializing {text_encoder_pretrained_model_name_or_path} as a text_encoder model "
+ "from a decoder model. Cross-attention and casual mask are disabled."
+ )
+ encoder_config.is_decoder = False
+ encoder_config.add_cross_attention = False
+
+ kwargs_text_encoder["config"] = encoder_config
+
+ text_encoder = AutoModel.from_pretrained(
+ text_encoder_pretrained_model_name_or_path, *model_args, **kwargs_text_encoder
+ )
+
+ audio_encoder = kwargs_audio_encoder.pop("model", None)
+ if audio_encoder is None:
+ if audio_encoder_pretrained_model_name_or_path is None:
+ raise ValueError(
+ "If `audio_encoder_model` is not defined as an argument, an `audio_encoder_pretrained_model_name_or_path` has "
+ "to be defined."
+ )
+
+ if "config" not in kwargs_audio_encoder:
+ encoder_config, kwargs_audio_encoder = AutoConfig.from_pretrained(
+ audio_encoder_pretrained_model_name_or_path, **kwargs_audio_encoder, return_unused_kwargs=True
+ )
+
+ if encoder_config.is_decoder is True or encoder_config.add_cross_attention is True:
+ logger.info(
+ f"Initializing {audio_encoder_pretrained_model_name_or_path} as an audio_encoder model "
+ "from a decoder model. Cross-attention and casual mask are disabled."
+ )
+ encoder_config.is_decoder = False
+ encoder_config.add_cross_attention = False
+
+ kwargs_audio_encoder["config"] = encoder_config
+
+ audio_encoder = AutoModel.from_pretrained(
+ audio_encoder_pretrained_model_name_or_path, *model_args, **kwargs_audio_encoder
+ )
+
+ decoder = kwargs_decoder.pop("model", None)
+ if decoder is None:
+ if decoder_pretrained_model_name_or_path is None:
+ raise ValueError(
+ "If `decoder_model` is not defined as an argument, a `decoder_pretrained_model_name_or_path` has "
+ "to be defined."
+ )
+
+ if "config" not in kwargs_decoder:
+ decoder_config, kwargs_decoder = AutoConfig.from_pretrained(
+ decoder_pretrained_model_name_or_path, **kwargs_decoder, return_unused_kwargs=True
+ )
+
+ if isinstance(decoder_config, MusicgenConfig):
+ decoder_config = decoder_config.decoder
+
+ if decoder_config.is_decoder is False or decoder_config.add_cross_attention is False:
+ logger.info(
+ f"Initializing {decoder_pretrained_model_name_or_path} as a decoder model. Cross attention"
+ f" layers are added to {decoder_pretrained_model_name_or_path} and randomly initialized if"
+ f" {decoder_pretrained_model_name_or_path}'s architecture allows for cross attention layers."
+ )
+ decoder_config.is_decoder = True
+ decoder_config.add_cross_attention = True
+
+ kwargs_decoder["config"] = decoder_config
+
+ if kwargs_decoder["config"].is_decoder is False or kwargs_decoder["config"].add_cross_attention is False:
+ logger.warning(
+ f"Decoder model {decoder_pretrained_model_name_or_path} is not initialized as a decoder. "
+ f"In order to initialize {decoder_pretrained_model_name_or_path} as a decoder, "
+ "make sure that the attributes `is_decoder` and `add_cross_attention` of `decoder_config` "
+ "passed to `.from_sub_models_pretrained(...)` are set to `True` or do not pass a "
+ "`decoder_config` to `.from_sub_models_pretrained(...)`"
+ )
+
+ decoder = MusicgenForCausalLM.from_pretrained(decoder_pretrained_model_name_or_path, **kwargs_decoder)
+
+ # instantiate config with corresponding kwargs
+ config = MusicgenConfig.from_sub_models_config(
+ text_encoder.config, audio_encoder.config, decoder.config, **kwargs
+ )
+ return cls(text_encoder=text_encoder, audio_encoder=audio_encoder, decoder=decoder, config=config)
+
+ @add_start_docstrings_to_model_forward(MUSICGEN_INPUTS_DOCSTRING)
+ @replace_return_docstrings(output_type=Seq2SeqLMOutput, config_class=_CONFIG_FOR_DOC)
+ def forward(
+ self,
+ input_ids: Optional[torch.LongTensor] = None,
+ attention_mask: Optional[torch.BoolTensor] = None,
+ input_values: Optional[torch.FloatTensor] = None,
+ padding_mask: Optional[torch.BoolTensor] = None,
+ decoder_input_ids: Optional[torch.LongTensor] = None,
+ decoder_attention_mask: Optional[torch.BoolTensor] = None,
+ encoder_outputs: Optional[Tuple[torch.FloatTensor]] = None,
+ past_key_values: Tuple[Tuple[torch.FloatTensor]] = None,
+ inputs_embeds: Optional[torch.FloatTensor] = None,
+ decoder_inputs_embeds: Optional[torch.FloatTensor] = None,
+ labels: Optional[torch.LongTensor] = None,
+ use_cache: Optional[bool] = None,
+ output_attentions: Optional[bool] = None,
+ output_hidden_states: Optional[bool] = None,
+ return_dict: Optional[bool] = None,
+ **kwargs,
+ ) -> Union[Tuple, Seq2SeqLMOutput]:
+ r"""
+ Returns:
+
+ Examples:
+ ```python
+ >>> from transformers import AutoProcessor, MusicgenForConditionalGeneration
+ >>> import torch
+
+ >>> processor = AutoProcessor.from_pretrained("facebook/musicgen-small")
+ >>> model = MusicgenForConditionalGeneration.from_pretrained("facebook/musicgen-small")
+
+ >>> inputs = processor(
+ ... text=["80s pop track with bassy drums and synth", "90s rock song with loud guitars and heavy drums"],
+ ... padding=True,
+ ... return_tensors="pt",
+ ... )
+
+ >>> pad_token_id = model.generation_config.pad_token_id
+ >>> decoder_input_ids = (
+ ... torch.ones((inputs.input_ids.shape[0] * model.decoder.num_codebooks, 1), dtype=torch.long)
+ ... * pad_token_id
+ ... )
+
+ >>> logits = model(**inputs, decoder_input_ids=decoder_input_ids).logits
+ >>> logits.shape # (bsz * num_codebooks, tgt_len, vocab_size)
+ torch.Size([8, 1, 2048])
+ ```"""
+ return_dict = return_dict if return_dict is not None else self.config.use_return_dict
+
+ kwargs_text_encoder = {
+ argument[len("text_encoder_")]: value
+ for argument, value in kwargs.items()
+ if argument.startswith("text_encoder_")
+ }
+
+ kwargs_audio_encoder = {
+ argument[len("audio_encoder_")]: value
+ for argument, value in kwargs.items()
+ if argument.startswith("audio_encoder_")
+ }
+
+ kwargs_decoder = {
+ argument[len("decoder_") :]: value for argument, value in kwargs.items() if argument.startswith("decoder_")
+ }
+
+ if encoder_outputs is None:
+ encoder_outputs = self.text_encoder(
+ input_ids=input_ids,
+ attention_mask=attention_mask,
+ inputs_embeds=inputs_embeds,
+ output_attentions=output_attentions,
+ output_hidden_states=output_hidden_states,
+ return_dict=return_dict,
+ **kwargs_text_encoder,
+ )
+ elif isinstance(encoder_outputs, tuple):
+ encoder_outputs = BaseModelOutput(*encoder_outputs)
+
+ encoder_hidden_states = encoder_outputs[0]
+
+ # optionally project encoder_hidden_states
+ if (
+ self.text_encoder.config.hidden_size != self.decoder.config.hidden_size
+ and self.decoder.config.cross_attention_hidden_size is None
+ ):
+ encoder_hidden_states = self.enc_to_dec_proj(encoder_hidden_states)
+
+ if attention_mask is not None:
+ encoder_hidden_states = encoder_hidden_states * attention_mask[..., None]
+
+ if (labels is not None) and (decoder_input_ids is None and decoder_inputs_embeds is None):
+ decoder_input_ids = shift_tokens_right(
+ labels, self.config.pad_token_id, self.config.decoder_start_token_id
+ )
+
+ elif decoder_input_ids is None and decoder_inputs_embeds is None:
+ audio_encoder_outputs = self.audio_encoder(
+ input_values=input_values,
+ padding_mask=padding_mask,
+ **kwargs_audio_encoder,
+ )
+ audio_codes = audio_encoder_outputs.audio_codes
+ frames, bsz, codebooks, seq_len = audio_codes.shape
+ if frames != 1:
+ raise ValueError(
+ f"Expected 1 frame in the audio code outputs, got {frames} frames. Ensure chunking is "
+ "disabled by setting `chunk_length=None` in the audio encoder."
+ )
+ decoder_input_ids = audio_codes[0, ...].reshape(bsz * self.decoder.num_codebooks, seq_len)
+
+ # Decode
+ decoder_outputs = self.decoder(
+ input_ids=decoder_input_ids,
+ attention_mask=decoder_attention_mask,
+ encoder_hidden_states=encoder_hidden_states,
+ encoder_attention_mask=attention_mask,
+ inputs_embeds=decoder_inputs_embeds,
+ output_attentions=output_attentions,
+ output_hidden_states=output_hidden_states,
+ use_cache=use_cache,
+ past_key_values=past_key_values,
+ return_dict=return_dict,
+ **kwargs_decoder,
+ )
+
+ loss = None
+ if labels is not None:
+ logits = decoder_outputs.logits if return_dict else decoder_outputs[0]
+ loss_fct = CrossEntropyLoss()
+ loss = loss_fct(logits.view(-1, self.config.vocab_size), labels.view(-1))
+
+ if not return_dict:
+ if loss is not None:
+ return (loss,) + decoder_outputs + encoder_outputs
+ else:
+ return decoder_outputs + encoder_outputs
+
+ return Seq2SeqLMOutput(
+ loss=loss,
+ logits=decoder_outputs.logits,
+ past_key_values=decoder_outputs.past_key_values,
+ decoder_hidden_states=decoder_outputs.hidden_states,
+ decoder_attentions=decoder_outputs.attentions,
+ cross_attentions=decoder_outputs.cross_attentions,
+ encoder_last_hidden_state=encoder_outputs.last_hidden_state,
+ encoder_hidden_states=encoder_outputs.hidden_states,
+ encoder_attentions=encoder_outputs.attentions,
+ )
+
+ def prepare_inputs_for_generation(
+ self,
+ decoder_input_ids,
+ past_key_values=None,
+ attention_mask=None,
+ head_mask=None,
+ decoder_attention_mask=None,
+ decoder_head_mask=None,
+ cross_attn_head_mask=None,
+ use_cache=None,
+ encoder_outputs=None,
+ decoder_delay_pattern_mask=None,
+ guidance_scale=None,
+ **kwargs,
+ ):
+ if decoder_delay_pattern_mask is None:
+ decoder_input_ids, decoder_delay_pattern_mask = self.decoder.build_delay_pattern_mask(
+ decoder_input_ids,
+ self.generation_config.pad_token_id,
+ max_length=self.generation_config.max_length,
+ )
+
+ # apply the delay pattern mask
+ decoder_input_ids = self.decoder.apply_delay_pattern_mask(decoder_input_ids, decoder_delay_pattern_mask)
+
+ if guidance_scale is not None and guidance_scale > 1:
+ # for classifier free guidance we need to replicate the decoder args across the batch dim (we'll split these
+ # before sampling)
+ decoder_input_ids = decoder_input_ids.repeat((2, 1))
+ if decoder_attention_mask is not None:
+ decoder_attention_mask = decoder_attention_mask.repeat((2, 1))
+
+ if past_key_values is not None:
+ past_length = past_key_values[0][0].shape[2]
+
+ # Some generation methods already pass only the last input ID
+ if decoder_input_ids.shape[1] > past_length:
+ remove_prefix_length = past_length
+ else:
+ # Default to old behavior: keep only final ID
+ remove_prefix_length = decoder_input_ids.shape[1] - 1
+
+ decoder_input_ids = decoder_input_ids[:, remove_prefix_length:]
+
+ return {
+ "input_ids": None, # encoder_outputs is defined. input_ids not needed
+ "encoder_outputs": encoder_outputs,
+ "past_key_values": past_key_values,
+ "decoder_input_ids": decoder_input_ids,
+ "attention_mask": attention_mask,
+ "decoder_attention_mask": decoder_attention_mask,
+ "head_mask": head_mask,
+ "decoder_head_mask": decoder_head_mask,
+ "cross_attn_head_mask": cross_attn_head_mask,
+ "use_cache": use_cache,
+ }
+
+ def _prepare_decoder_input_ids_for_generation(
+ self,
+ batch_size: int,
+ model_input_name: str,
+ model_kwargs: Dict[str, torch.Tensor],
+ decoder_start_token_id: int = None,
+ bos_token_id: int = None,
+ device: torch.device = None,
+ ) -> Tuple[torch.LongTensor, Dict[str, torch.Tensor]]:
+ """Prepares `decoder_input_ids` for generation with encoder-decoder models"""
+
+ # 1. Check whether the user has defined `decoder_input_ids` manually. To facilitate in terms of input naming,
+ # we also allow the user to pass it under `input_ids`, if the encoder does not use it as the main input.
+ if model_kwargs is not None and "decoder_input_ids" in model_kwargs:
+ decoder_input_ids = model_kwargs.pop("decoder_input_ids")
+ elif "input_ids" in model_kwargs and model_input_name != "input_ids":
+ decoder_input_ids = model_kwargs.pop("input_ids")
+ else:
+ decoder_input_ids = None
+
+ # 2. Encoder-decoder models expect the `decoder_input_ids` to start with a special token. Let's ensure that.
+ decoder_start_token_id = self._get_decoder_start_token_id(decoder_start_token_id, bos_token_id)
+ if device is None:
+ device = self.device
+ decoder_input_ids_start = (
+ torch.ones((batch_size * self.decoder.num_codebooks, 1), dtype=torch.long, device=device)
+ * decoder_start_token_id
+ )
+
+ # no user input -> use decoder_start_token_id as decoder_input_ids
+ if decoder_input_ids is None:
+ decoder_input_ids = decoder_input_ids_start
+
+ # user input but doesn't start with decoder_start_token_id -> prepend decoder_start_token_id (and adjust
+ # decoder_attention_mask if provided)
+ elif (decoder_input_ids[..., 0] != decoder_start_token_id).all().item():
+ decoder_input_ids = torch.cat([decoder_input_ids_start, decoder_input_ids], dim=-1)
+ if "decoder_attention_mask" in model_kwargs:
+ decoder_attention_mask = model_kwargs["decoder_attention_mask"]
+ decoder_attention_mask = torch.cat(
+ (torch.ones_like(decoder_attention_mask)[:, :1], decoder_attention_mask),
+ dim=-1,
+ )
+ model_kwargs["decoder_attention_mask"] = decoder_attention_mask
+
+ return decoder_input_ids, model_kwargs
+
+ def _prepare_text_encoder_kwargs_for_generation(
+ self,
+ inputs_tensor: torch.Tensor,
+ model_kwargs,
+ model_input_name: Optional[str] = None,
+ guidance_scale: Optional[float] = None,
+ ) -> Dict[str, Any]:
+ # 1. get text encoder
+ encoder = self.get_text_encoder()
+ # Compatibility with Accelerate big model inference: we need the encoder to outputs stuff on the same device
+ # as the inputs.
+ if hasattr(encoder, "_hf_hook"):
+ encoder._hf_hook.io_same_device = True
+
+ # 2. Prepare encoder args and encoder kwargs from model kwargs.
+ irrelevant_prefix = ["decoder_", "cross_attn", "use_cache"]
+ encoder_kwargs = {
+ argument: value
+ for argument, value in model_kwargs.items()
+ if not any(argument.startswith(p) for p in irrelevant_prefix)
+ }
+ encoder_signature = set(inspect.signature(encoder.forward).parameters)
+ encoder_accepts_wildcard = "kwargs" in encoder_signature or "model_kwargs" in encoder_signature
+ if not encoder_accepts_wildcard:
+ encoder_kwargs = {
+ argument: value for argument, value in encoder_kwargs.items() if argument in encoder_signature
+ }
+
+ # 3. make sure that encoder returns `ModelOutput`
+ model_input_name = model_input_name if model_input_name is not None else self.text_encoder.main_input_name
+ encoder_kwargs["return_dict"] = True
+ encoder_kwargs[model_input_name] = inputs_tensor
+ last_hidden_state = encoder(**encoder_kwargs).last_hidden_state
+
+ # for classifier free guidance we need to add a 'null' input to our encoder hidden states
+ if guidance_scale is not None and guidance_scale > 1:
+ last_hidden_state = torch.concatenate([last_hidden_state, torch.zeros_like(last_hidden_state)], dim=0)
+ if "attention_mask" in model_kwargs:
+ model_kwargs["attention_mask"] = torch.concatenate(
+ [model_kwargs["attention_mask"], torch.zeros_like(model_kwargs["attention_mask"])], dim=0
+ )
+
+ model_kwargs["encoder_outputs"] = BaseModelOutput(last_hidden_state=last_hidden_state)
+
+ return model_kwargs
+
+ def _prepare_audio_encoder_kwargs_for_generation(
+ self, input_values, model_kwargs, model_input_name: Optional[str] = None
+ ):
+ # 1. get audio encoder
+ encoder = self.get_audio_encoder()
+ # Compatibility with Accelerate big model inference: we need the encoder to outputs stuff on the same device
+ # as the inputs.
+ if hasattr(encoder, "_hf_hook"):
+ encoder._hf_hook.io_same_device = True
+
+ # 2. Prepare encoder args and encoder kwargs from model kwargs.
+ irrelevant_prefix = ["decoder_", "cross_attn", "use_cache"]
+ encoder_kwargs = {
+ argument: value
+ for argument, value in model_kwargs.items()
+ if not any(argument.startswith(p) for p in irrelevant_prefix)
+ }
+ encoder_signature = set(inspect.signature(encoder.forward).parameters)
+ encoder_accepts_wildcard = "kwargs" in encoder_signature or "model_kwargs" in encoder_signature
+ if not encoder_accepts_wildcard:
+ encoder_kwargs = {
+ argument: value for argument, value in encoder_kwargs.items() if argument in encoder_signature
+ }
+
+ # 3. make sure that encoder returns `ModelOutput`
+ model_input_name = model_input_name if model_input_name is not None else self.audio_encoder.main_input_name
+ encoder_kwargs["return_dict"] = True
+ encoder_kwargs[model_input_name] = input_values
+
+ audio_encoder_outputs = encoder.encode(**encoder_kwargs)
+
+ audio_codes = audio_encoder_outputs.audio_codes
+ frames, bsz, codebooks, seq_len = audio_codes.shape
+
+ if frames != 1:
+ raise ValueError(
+ f"Expected 1 frame in the audio code outputs, got {frames} frames. Ensure chunking is "
+ "disabled by setting `chunk_length=None` in the audio encoder."
+ )
+
+ decoder_input_ids = audio_codes[0, ...].reshape(bsz * self.decoder.num_codebooks, seq_len)
+
+ model_kwargs["decoder_input_ids"] = decoder_input_ids
+ model_kwargs["audio_scales"] = audio_encoder_outputs.audio_scales
+ return model_kwargs
+
+ def prepare_decoder_input_ids_from_labels(self, labels: torch.Tensor):
+ return shift_tokens_right(labels, self.config.pad_token_id, self.config.decoder_start_token_id)
+
+ def resize_token_embeddings(self, *args, **kwargs):
+ raise NotImplementedError(
+ "Resizing the embedding layers via the EncoderDecoderModel directly is not supported. Please use the"
+ " respective methods of the wrapped objects (model.encoder.resize_token_embeddings(...) or"
+ " model.decoder.resize_token_embeddings(...))"
+ )
+
+ def _maybe_initialize_input_ids_for_generation(
+ self,
+ inputs: Optional[torch.Tensor] = None,
+ bos_token_id: Optional[int] = None,
+ model_kwargs: Optional[Dict[str, torch.Tensor]] = None,
+ ) -> torch.LongTensor:
+ """Initializes input ids for generation, if necessary."""
+ if inputs is not None:
+ return inputs
+
+ encoder_outputs = model_kwargs.get("encoder_outputs")
+ if encoder_outputs is not None:
+ # make dummy input_ids with value -100, as a sanity check ensuring that they won't be used for encoding
+ shape = encoder_outputs[0].size()[:-1]
+ return torch.ones(shape, dtype=torch.long, device=self.device) * -100
+
+ if bos_token_id is None:
+ raise ValueError("`bos_token_id` has to be defined when no `input_ids` are provided.")
+
+ # If there is some tensor in `model_kwargs`, we can infer the batch size from it. This is helpful with
+ # soft-prompting or in multimodal implementations built on top of decoder-only language models.
+ batch_size = 1
+ for value in model_kwargs.values():
+ if isinstance(value, torch.Tensor):
+ batch_size = value.shape[0]
+ break
+ return torch.ones((batch_size, 1), dtype=torch.long, device=self.device) * bos_token_id
+
+ @torch.no_grad()
+ def generate(
+ self,
+ inputs: Optional[torch.Tensor] = None,
+ generation_config: Optional[GenerationConfig] = None,
+ logits_processor: Optional[LogitsProcessorList] = None,
+ stopping_criteria: Optional[StoppingCriteriaList] = None,
+ synced_gpus: Optional[bool] = None,
+ streamer: Optional["BaseStreamer"] = None,
+ encoder_only: Optional[bool] = False,
+ **kwargs,
+ ):
+ """
+
+ Generates sequences of token ids for models with a language modeling head.
+
+
+
+ Most generation-controlling parameters are set in `generation_config` which, if not passed, will be set to the
+ model's default generation configuration. You can override any `generation_config` by passing the corresponding
+ parameters to generate(), e.g. `.generate(inputs, num_beams=4, do_sample=True)`.
+
+ For an overview of generation strategies and code examples, check out the [following
+ guide](./generation_strategies).
+
+
+
+ Parameters:
+ inputs (`torch.Tensor` of varying shape depending on the modality, *optional*):
+ The sequence used as a prompt for the generation or as model inputs to the encoder. If `None` the
+ method initializes it with `bos_token_id` and a batch size of 1. For decoder-only models `inputs`
+ should be in the format `input_ids`. For encoder-decoder models *inputs* can represent any of
+ `input_ids`, `input_values`, `input_features`, or `pixel_values`.
+ generation_config (`~generation.GenerationConfig`, *optional*):
+ The generation configuration to be used as base parametrization for the generation call. `**kwargs`
+ passed to generate matching the attributes of `generation_config` will override them. If
+ `generation_config` is not provided, the default will be used, which had the following loading
+ priority: 1) from the `generation_config.json` model file, if it exists; 2) from the model
+ configuration. Please note that unspecified parameters will inherit [`~generation.GenerationConfig`]'s
+ default values, whose documentation should be checked to parameterize generation.
+ logits_processor (`LogitsProcessorList`, *optional*):
+ Custom logits processors that complement the default logits processors built from arguments and
+ generation config. If a logit processor is passed that is already created with the arguments or a
+ generation config an error is thrown. This feature is intended for advanced users.
+ stopping_criteria (`StoppingCriteriaList`, *optional*):
+ Custom stopping criteria that complement the default stopping criteria built from arguments and a
+ generation config. If a stopping criteria is passed that is already created with the arguments or a
+ generation config an error is thrown. This feature is intended for advanced users.
+ synced_gpus (`bool`, *optional*, defaults to `False`):
+ Whether to continue running the while loop until max_length (needed for ZeRO stage 3)
+ streamer (`BaseStreamer`, *optional*):
+ Streamer object that will be used to stream the generated sequences. Generated tokens are passed
+ through `streamer.put(token_ids)` and the streamer is responsible for any further processing.
+ kwargs (`Dict[str, Any]`, *optional*):
+ Ad hoc parametrization of `generate_config` and/or additional model-specific kwargs that will be
+ forwarded to the `forward` function of the model. If the model is an encoder-decoder model, encoder
+ specific kwargs should not be prefixed and decoder specific kwargs should be prefixed with *decoder_*.
+
+ Return:
+ [`~utils.ModelOutput`] or `torch.LongTensor`: A [`~utils.ModelOutput`] (if `return_dict_in_generate=True`
+ or when `config.return_dict_in_generate=True`) or a `torch.FloatTensor`.
+
+ If the model is *not* an encoder-decoder model (`model.config.is_encoder_decoder=False`), the possible
+ [`~utils.ModelOutput`] types are:
+
+ - [`~generation.GreedySearchDecoderOnlyOutput`],
+ - [`~generation.SampleDecoderOnlyOutput`],
+ - [`~generation.BeamSearchDecoderOnlyOutput`],
+ - [`~generation.BeamSampleDecoderOnlyOutput`]
+
+ If the model is an encoder-decoder model (`model.config.is_encoder_decoder=True`), the possible
+ [`~utils.ModelOutput`] types are:
+
+ - [`~generation.GreedySearchEncoderDecoderOutput`],
+ - [`~generation.SampleEncoderDecoderOutput`],
+ - [`~generation.BeamSearchEncoderDecoderOutput`],
+ - [`~generation.BeamSampleEncoderDecoderOutput`]
+ """
+ # 1. Handle `generation_config` and kwargs that might update it, and validate the resulting objects
+ if generation_config is None:
+ generation_config = self.generation_config
+
+ generation_config = copy.deepcopy(generation_config)
+ model_kwargs = generation_config.update(**kwargs) # All unused kwargs must be model kwargs
+ generation_config.validate()
+ self._validate_model_kwargs(model_kwargs.copy())
+
+ if model_kwargs.get("encoder_outputs") is not None and type(model_kwargs["encoder_outputs"]) == tuple:
+ # wrap the unconditional outputs as a BaseModelOutput for compatibility with the rest of generate
+ model_kwargs["encoder_outputs"] = BaseModelOutput(last_hidden_state=model_kwargs["encoder_outputs"][0])
+
+ # 2. Set generation parameters if not already defined
+ logits_processor = logits_processor if logits_processor is not None else LogitsProcessorList()
+ stopping_criteria = stopping_criteria if stopping_criteria is not None else StoppingCriteriaList()
+
+ if generation_config.pad_token_id is None and generation_config.eos_token_id is not None:
+ if model_kwargs.get("attention_mask", None) is None:
+ logger.warning(
+ "The attention mask and the pad token id were not set. As a consequence, you may observe "
+ "unexpected behavior. Please pass your input's `attention_mask` to obtain reliable results."
+ )
+ eos_token_id = generation_config.eos_token_id
+ if isinstance(eos_token_id, list):
+ eos_token_id = eos_token_id[0]
+ logger.warning(f"Setting `pad_token_id` to `eos_token_id`:{eos_token_id} for open-end generation.")
+ generation_config.pad_token_id = eos_token_id
+
+ # 3. Define model inputs
+ # inputs_tensor has to be defined
+ # model_input_name is defined if model-specific keyword input is passed
+ # otherwise model_input_name is None
+ # all model-specific keyword inputs are removed from `model_kwargs`
+ inputs_tensor, model_input_name, model_kwargs = self._prepare_model_inputs(
+ inputs, generation_config.bos_token_id, model_kwargs
+ )
+ batch_size = inputs_tensor.shape[0]
+
+ # 4. Define other model kwargs
+ model_kwargs["output_attentions"] = generation_config.output_attentions
+ model_kwargs["output_hidden_states"] = generation_config.output_hidden_states
+ model_kwargs["use_cache"] = generation_config.use_cache
+ model_kwargs["guidance_scale"] = generation_config.guidance_scale
+
+ requires_attention_mask = "encoder_outputs" not in model_kwargs
+
+ if model_kwargs.get("attention_mask", None) is None and requires_attention_mask:
+ model_kwargs["attention_mask"] = self._prepare_attention_mask_for_generation(
+ inputs_tensor, generation_config.pad_token_id, generation_config.eos_token_id
+ )
+
+ if "encoder_outputs" not in model_kwargs:
+ # encoder_outputs are created and added to `model_kwargs`
+ model_kwargs = self._prepare_text_encoder_kwargs_for_generation(
+ inputs_tensor,
+ model_kwargs,
+ model_input_name,
+ guidance_scale=generation_config.guidance_scale,
+ )
+
+ if encoder_only:
+ return model_kwargs['encoder_outputs']['last_hidden_state']
+
+ if "decoder_input_ids" not in model_kwargs and "input_values" in model_kwargs:
+ model_kwargs = self._prepare_audio_encoder_kwargs_for_generation(
+ model_kwargs["input_values"],
+ model_kwargs,
+ )
+
+ # 5. Prepare `input_ids` which will be used for auto-regressive generation
+ input_ids, model_kwargs = self._prepare_decoder_input_ids_for_generation(
+ batch_size=batch_size,
+ model_input_name=model_input_name,
+ model_kwargs=model_kwargs,
+ decoder_start_token_id=generation_config.decoder_start_token_id,
+ bos_token_id=generation_config.bos_token_id,
+ device=inputs_tensor.device,
+ )
+
+ # 6. Prepare `max_length` depending on other stopping criteria.
+ input_ids_seq_length = input_ids.shape[-1]
+ has_default_max_length = kwargs.get("max_length") is None and generation_config.max_length is not None
+ if has_default_max_length and generation_config.max_new_tokens is None:
+ logger.warning(
+ f"Using the model-agnostic default `max_length` (={generation_config.max_length}) "
+ "to control the generation length. We recommend setting `max_new_tokens` to control the maximum length of the generation."
+ )
+ elif generation_config.max_new_tokens is not None:
+ if not has_default_max_length:
+ logger.warning(
+ f"Both `max_new_tokens` (={generation_config.max_new_tokens}) and `max_length`(="
+ f"{generation_config.max_length}) seem to have been set. `max_new_tokens` will take precedence. "
+ "Please refer to the documentation for more information. "
+ "(https://huggingface.co/docs/transformers/main/en/main_classes/text_generation)"
+ )
+ generation_config.max_length = generation_config.max_new_tokens + input_ids_seq_length
+
+ if generation_config.min_length is not None and generation_config.min_length > generation_config.max_length:
+ raise ValueError(
+ f"Unfeasible length constraints: the minimum length ({generation_config.min_length}) is larger than"
+ f" the maximum length ({generation_config.max_length})"
+ )
+ if input_ids_seq_length >= generation_config.max_length:
+ logger.warning(
+ f"Input length of decoder_input_ids is {input_ids_seq_length}, but `max_length` is set to"
+ f" {generation_config.max_length}. This can lead to unexpected behavior. You should consider"
+ " increasing `max_new_tokens`."
+ )
+ # build the delay pattern mask for offsetting each codebook prediction by 1 (this behaviour is specific to MusicGen)
+ input_ids, decoder_delay_pattern_mask = self.decoder.build_delay_pattern_mask(
+ input_ids,
+ pad_token_id=generation_config.decoder_start_token_id,
+ max_length=generation_config.max_length,
+ )
+
+ # stash the delay mask so that we don't have to recompute in each forward pass
+ model_kwargs["decoder_delay_pattern_mask"] = decoder_delay_pattern_mask
+
+ # input_ids are ready to be placed on the streamer (if used)
+ if streamer is not None:
+ streamer.put(input_ids.cpu())
+
+ # 7. determine generation mode
+ is_greedy_gen_mode = (
+ (generation_config.num_beams == 1)
+ and (generation_config.num_beam_groups == 1)
+ and generation_config.do_sample is False
+ )
+ is_sample_gen_mode = (
+ (generation_config.num_beams == 1)
+ and (generation_config.num_beam_groups == 1)
+ and generation_config.do_sample is True
+ )
+
+ # 8. prepare batched CFG externally (to enable coexistance with the unbatched CFG)
+ if generation_config.guidance_scale is not None and generation_config.guidance_scale > 1:
+ logits_processor.append(ClassifierFreeGuidanceLogitsProcessor(generation_config.guidance_scale))
+ generation_config.guidance_scale = None
+
+ # 9. prepare distribution pre_processing samplers
+ logits_processor = self._get_logits_processor(
+ generation_config=generation_config,
+ input_ids_seq_length=input_ids_seq_length,
+ encoder_input_ids=inputs_tensor,
+ prefix_allowed_tokens_fn=None,
+ logits_processor=logits_processor,
+ )
+
+ # 10. prepare stopping criteria
+ stopping_criteria = self._get_stopping_criteria(
+ generation_config=generation_config, stopping_criteria=stopping_criteria
+ )
+
+ if is_greedy_gen_mode:
+ if generation_config.num_return_sequences > 1:
+ raise ValueError(
+ "num_return_sequences has to be 1 when doing greedy search, "
+ f"but is {generation_config.num_return_sequences}."
+ )
+
+ # 11. run greedy search
+ outputs = self.greedy_search(
+ input_ids,
+ logits_processor=logits_processor,
+ stopping_criteria=stopping_criteria,
+ pad_token_id=generation_config.pad_token_id,
+ eos_token_id=generation_config.eos_token_id,
+ output_scores=generation_config.output_scores,
+ return_dict_in_generate=generation_config.return_dict_in_generate,
+ synced_gpus=synced_gpus,
+ streamer=streamer,
+ **model_kwargs,
+ )
+
+ elif is_sample_gen_mode:
+ # 11. prepare logits warper
+ logits_warper = self._get_logits_warper(generation_config)
+
+ # expand input_ids with `num_return_sequences` additional sequences per batch
+ input_ids, model_kwargs = self._expand_inputs_for_generation(
+ input_ids=input_ids,
+ expand_size=generation_config.num_return_sequences,
+ is_encoder_decoder=self.config.is_encoder_decoder,
+ **model_kwargs,
+ )
+
+ # 12. run sample
+ outputs = self.sample(
+ input_ids,
+ logits_processor=logits_processor,
+ logits_warper=logits_warper,
+ stopping_criteria=stopping_criteria,
+ pad_token_id=generation_config.pad_token_id,
+ eos_token_id=generation_config.eos_token_id,
+ output_scores=generation_config.output_scores,
+ return_dict_in_generate=generation_config.return_dict_in_generate,
+ synced_gpus=synced_gpus,
+ streamer=streamer,
+ **model_kwargs,
+ )
+
+ else:
+ raise ValueError(
+ "Got incompatible mode for generation, should be one of greedy or sampling. "
+ "Ensure that beam search is de-activated by setting `num_beams=1` and `num_beam_groups=1`."
+ )
+
+ if generation_config.return_dict_in_generate:
+ output_ids = outputs.sequences
+ else:
+ output_ids = outputs
+
+ # apply the pattern mask to the final ids
+ output_ids = self.decoder.apply_delay_pattern_mask(output_ids, model_kwargs["decoder_delay_pattern_mask"])
+
+ # revert the pattern delay mask by filtering the pad token id
+ output_ids = output_ids[output_ids != generation_config.pad_token_id].reshape(
+ batch_size, self.decoder.num_codebooks, -1
+ )
+
+ # append the frame dimension back to the audio codes
+ output_ids = output_ids[None, ...]
+
+ audio_scales = model_kwargs.get("audio_scales")
+ if audio_scales is None:
+ audio_scales = [None] * batch_size
+
+ output_values = self.audio_encoder.decode(
+ output_ids,
+ audio_scales=audio_scales,
+ )
+
+ if generation_config.return_dict_in_generate:
+ outputs.sequences = output_values.audio_values
+ return outputs
+ else:
+ return output_values.audio_values
+
+ def get_unconditional_inputs(self, num_samples=1):
+ """
+ Helper function to get null inputs for unconditional generation, enabling the model to be used without the
+ feature extractor or tokenizer.
+
+ Args:
+ num_samples (int, *optional*):
+ Number of audio samples to unconditionally generate.
+ max_new_tokens (int, *optional*):
+ Number of tokens to generate for each sample. More tokens means longer audio samples, at the expense of
+ longer inference (since more audio tokens need to be generated per sample).
+
+ Example:
+ ```python
+ >>> from transformers import MusicgenForConditionalGeneration
+
+ >>> model = MusicgenForConditionalGeneration.from_pretrained("facebook/musicgen-small")
+
+ >>> # get the unconditional (or 'null') inputs for the model
+ >>> unconditional_inputs = model.get_unconditional_inputs(num_samples=1)
+ >>> audio_samples = model.generate(**unconditional_inputs, max_new_tokens=256)
+ ```"""
+ last_hidden_state = torch.zeros(
+ (num_samples, 1, self.config.text_encoder.hidden_size), device=self.device, dtype=self.dtype
+ )
+
+ attention_mask = torch.zeros((num_samples, 1), device=self.device, dtype=torch.long)
+
+ return MusicgenUnconditionalInput(
+ encoder_outputs=(last_hidden_state,),
+ attention_mask=attention_mask,
+ guidance_scale=1.0,
+ )
\ No newline at end of file