StableAvatar / wan /models /vocal_projector_fantasy.py
YinmingHuang's picture
Add application file
cf2f35c
import os
import torch
import torch.nn as nn
import torch.nn.functional as F
class VocalProjModel(nn.Module):
def __init__(self, audio_in_dim=1024, cross_attention_dim=1024):
super().__init__()
self.cross_attention_dim = cross_attention_dim
self.proj = torch.nn.Linear(audio_in_dim, cross_attention_dim, bias=False)
self.norm = torch.nn.LayerNorm(cross_attention_dim)
def forward(self, audio_embeds):
context_tokens = self.proj(audio_embeds)
context_tokens = self.norm(context_tokens)
return context_tokens # [B,L,C]
class FantasyTalkingVocalConditionModel(nn.Module):
def __init__(self, audio_in_dim: int, audio_proj_dim: int):
super().__init__()
self.audio_in_dim = audio_in_dim
self.audio_proj_dim = audio_proj_dim
# audio proj model
self.proj_model = self.init_proj(self.audio_proj_dim)
def init_proj(self, cross_attention_dim=5120):
proj_model = VocalProjModel(
audio_in_dim=self.audio_in_dim, cross_attention_dim=cross_attention_dim
)
return proj_model
def forward(self, audio_fea=None):
return self.proj_model(audio_fea) if audio_fea is not None else None
def split_audio_sequence(audio_proj_length, num_frames=81):
"""
Map the audio feature sequence to corresponding latent frame slices.
Args:
audio_proj_length (int): The total length of the audio feature sequence
(e.g., 173 in audio_proj[1, 173, 768]).
num_frames (int): The number of video frames in the training data (default: 81).
Returns:
list: A list of [start_idx, end_idx] pairs. Each pair represents the index range
(within the audio feature sequence) corresponding to a latent frame.
"""
# Average number of tokens per original video frame
tokens_per_frame = audio_proj_length / num_frames
# Each latent frame covers 4 video frames, and we want the center
tokens_per_latent_frame = tokens_per_frame * 4
half_tokens = int(tokens_per_latent_frame / 2)
pos_indices = []
for i in range(int((num_frames - 1) / 4) + 1):
if i == 0:
pos_indices.append(0)
else:
start_token = tokens_per_frame * ((i - 1) * 4 + 1)
end_token = tokens_per_frame * (i * 4 + 1)
center_token = int((start_token + end_token) / 2) - 1
pos_indices.append(center_token)
# Build index ranges centered around each position
pos_idx_ranges = [[idx - half_tokens, idx + half_tokens] for idx in pos_indices]
# Adjust the first range to avoid negative start index
pos_idx_ranges[0] = [
-(half_tokens * 2 - pos_idx_ranges[1][0]),
pos_idx_ranges[1][0],
]
return pos_idx_ranges
def split_tensor_with_padding(input_tensor, pos_idx_ranges, expand_length=0):
"""
Split the input tensor into subsequences based on index ranges, and apply right-side zero-padding
if the range exceeds the input boundaries.
Args:
input_tensor (Tensor): Input audio tensor of shape [1, L, 768].
pos_idx_ranges (list): A list of index ranges, e.g. [[-7, 1], [1, 9], ..., [165, 173]].
expand_length (int): Number of tokens to expand on both sides of each subsequence.
Returns:
sub_sequences (Tensor): A tensor of shape [1, F, L, 768], where L is the length after padding.
Each element is a padded subsequence.
k_lens (Tensor): A tensor of shape [F], representing the actual (unpadded) length of each subsequence.
Useful for ignoring padding tokens in attention masks.
"""
pos_idx_ranges = [
[idx[0] - expand_length, idx[1] + expand_length] for idx in pos_idx_ranges
]
sub_sequences = []
seq_len = input_tensor.size(1) # 173
max_valid_idx = seq_len - 1 # 172
k_lens_list = []
for start, end in pos_idx_ranges:
# Calculate the fill amount
pad_front = max(-start, 0)
pad_back = max(end - max_valid_idx, 0)
# Calculate the start and end indices of the valid part
valid_start = max(start, 0)
valid_end = min(end, max_valid_idx)
# Extract the valid part
if valid_start <= valid_end:
valid_part = input_tensor[:, valid_start: valid_end + 1, :]
else:
valid_part = input_tensor.new_zeros((1, 0, input_tensor.size(2)))
# In the sequence dimension (the 1st dimension) perform padding
padded_subseq = F.pad(
valid_part,
(0, 0, 0, pad_back + pad_front, 0, 0),
mode="constant",
value=0,
)
k_lens_list.append(padded_subseq.size(-2) - pad_back - pad_front)
sub_sequences.append(padded_subseq)
return torch.stack(sub_sequences, dim=1), torch.tensor(
k_lens_list, dtype=torch.long
)