Basic Genmo Mochi video model support.

To use:
"Load CLIP" node with t5xxl + type mochi
"Load Diffusion Model" node with the mochi dit file.
"Load VAE" with the mochi vae file.

EmptyMochiLatentVideo node for the latent.
euler + linear_quadratic in the KSampler node.
This commit is contained in:
comfyanonymous
2024-10-26 06:54:00 -04:00
parent c3ffbae067
commit 5cbb01bc2f
18 changed files with 1677 additions and 24 deletions

View File

@@ -0,0 +1,541 @@
#original code from https://github.com/genmoai/models under apache 2.0 license
#adapted to ComfyUI
from typing import Dict, List, Optional, Tuple
import torch
import torch.nn as nn
import torch.nn.functional as F
from einops import rearrange
# from flash_attn import flash_attn_varlen_qkvpacked_func
from comfy.ldm.modules.attention import optimized_attention
from .layers import (
FeedForward,
PatchEmbed,
RMSNorm,
TimestepEmbedder,
)
from .rope_mixed import (
compute_mixed_rotation,
create_position_matrix,
)
from .temporal_rope import apply_rotary_emb_qk_real
from .utils import (
AttentionPool,
modulate,
)
import comfy.ldm.common_dit
import comfy.ops
def modulated_rmsnorm(x, scale, eps=1e-6):
# Normalize and modulate
x_normed = comfy.ldm.common_dit.rms_norm(x, eps=eps)
x_modulated = x_normed * (1 + scale.unsqueeze(1))
return x_modulated
def residual_tanh_gated_rmsnorm(x, x_res, gate, eps=1e-6):
# Apply tanh to gate
tanh_gate = torch.tanh(gate).unsqueeze(1)
# Normalize and apply gated scaling
x_normed = comfy.ldm.common_dit.rms_norm(x_res, eps=eps) * tanh_gate
# Apply residual connection
output = x + x_normed
return output
class AsymmetricAttention(nn.Module):
def __init__(
self,
dim_x: int,
dim_y: int,
num_heads: int = 8,
qkv_bias: bool = True,
qk_norm: bool = False,
attn_drop: float = 0.0,
update_y: bool = True,
out_bias: bool = True,
attend_to_padding: bool = False,
softmax_scale: Optional[float] = None,
device: Optional[torch.device] = None,
dtype=None,
operations=None,
):
super().__init__()
self.dim_x = dim_x
self.dim_y = dim_y
self.num_heads = num_heads
self.head_dim = dim_x // num_heads
self.attn_drop = attn_drop
self.update_y = update_y
self.attend_to_padding = attend_to_padding
self.softmax_scale = softmax_scale
if dim_x % num_heads != 0:
raise ValueError(
f"dim_x={dim_x} should be divisible by num_heads={num_heads}"
)
# Input layers.
self.qkv_bias = qkv_bias
self.qkv_x = operations.Linear(dim_x, 3 * dim_x, bias=qkv_bias, device=device, dtype=dtype)
# Project text features to match visual features (dim_y -> dim_x)
self.qkv_y = operations.Linear(dim_y, 3 * dim_x, bias=qkv_bias, device=device, dtype=dtype)
# Query and key normalization for stability.
assert qk_norm
self.q_norm_x = RMSNorm(self.head_dim, device=device, dtype=dtype)
self.k_norm_x = RMSNorm(self.head_dim, device=device, dtype=dtype)
self.q_norm_y = RMSNorm(self.head_dim, device=device, dtype=dtype)
self.k_norm_y = RMSNorm(self.head_dim, device=device, dtype=dtype)
# Output layers. y features go back down from dim_x -> dim_y.
self.proj_x = operations.Linear(dim_x, dim_x, bias=out_bias, device=device, dtype=dtype)
self.proj_y = (
operations.Linear(dim_x, dim_y, bias=out_bias, device=device, dtype=dtype)
if update_y
else nn.Identity()
)
def forward(
self,
x: torch.Tensor, # (B, N, dim_x)
y: torch.Tensor, # (B, L, dim_y)
scale_x: torch.Tensor, # (B, dim_x), modulation for pre-RMSNorm.
scale_y: torch.Tensor, # (B, dim_y), modulation for pre-RMSNorm.
crop_y,
**rope_rotation,
) -> Tuple[torch.Tensor, torch.Tensor]:
rope_cos = rope_rotation.get("rope_cos")
rope_sin = rope_rotation.get("rope_sin")
# Pre-norm for visual features
x = modulated_rmsnorm(x, scale_x) # (B, M, dim_x) where M = N / cp_group_size
# Process visual features
# qkv_x = self.qkv_x(x) # (B, M, 3 * dim_x)
# assert qkv_x.dtype == torch.bfloat16
# qkv_x = all_to_all_collect_tokens(
# qkv_x, self.num_heads
# ) # (3, B, N, local_h, head_dim)
# Process text features
y = modulated_rmsnorm(y, scale_y) # (B, L, dim_y)
q_y, k_y, v_y = self.qkv_y(y).view(y.shape[0], y.shape[1], 3, self.num_heads, -1).unbind(2) # (B, N, local_h, head_dim)
q_y = self.q_norm_y(q_y)
k_y = self.k_norm_y(k_y)
# Split qkv_x into q, k, v
q_x, k_x, v_x = self.qkv_x(x).view(x.shape[0], x.shape[1], 3, self.num_heads, -1).unbind(2) # (B, N, local_h, head_dim)
q_x = self.q_norm_x(q_x)
q_x = apply_rotary_emb_qk_real(q_x, rope_cos, rope_sin)
k_x = self.k_norm_x(k_x)
k_x = apply_rotary_emb_qk_real(k_x, rope_cos, rope_sin)
q = torch.cat([q_x, q_y[:, :crop_y]], dim=1).transpose(1, 2)
k = torch.cat([k_x, k_y[:, :crop_y]], dim=1).transpose(1, 2)
v = torch.cat([v_x, v_y[:, :crop_y]], dim=1).transpose(1, 2)
xy = optimized_attention(q,
k,
v, self.num_heads, skip_reshape=True)
x, y = torch.tensor_split(xy, (q_x.shape[1],), dim=1)
x = self.proj_x(x)
o = torch.zeros(y.shape[0], q_y.shape[1], y.shape[-1], device=y.device, dtype=y.dtype)
o[:, :y.shape[1]] = y
y = self.proj_y(o)
# print("ox", x)
# print("oy", y)
return x, y
class AsymmetricJointBlock(nn.Module):
def __init__(
self,
hidden_size_x: int,
hidden_size_y: int,
num_heads: int,
*,
mlp_ratio_x: float = 8.0, # Ratio of hidden size to d_model for MLP for visual tokens.
mlp_ratio_y: float = 4.0, # Ratio of hidden size to d_model for MLP for text tokens.
update_y: bool = True, # Whether to update text tokens in this block.
device: Optional[torch.device] = None,
dtype=None,
operations=None,
**block_kwargs,
):
super().__init__()
self.update_y = update_y
self.hidden_size_x = hidden_size_x
self.hidden_size_y = hidden_size_y
self.mod_x = operations.Linear(hidden_size_x, 4 * hidden_size_x, device=device, dtype=dtype)
if self.update_y:
self.mod_y = operations.Linear(hidden_size_x, 4 * hidden_size_y, device=device, dtype=dtype)
else:
self.mod_y = operations.Linear(hidden_size_x, hidden_size_y, device=device, dtype=dtype)
# Self-attention:
self.attn = AsymmetricAttention(
hidden_size_x,
hidden_size_y,
num_heads=num_heads,
update_y=update_y,
device=device,
dtype=dtype,
operations=operations,
**block_kwargs,
)
# MLP.
mlp_hidden_dim_x = int(hidden_size_x * mlp_ratio_x)
assert mlp_hidden_dim_x == int(1536 * 8)
self.mlp_x = FeedForward(
in_features=hidden_size_x,
hidden_size=mlp_hidden_dim_x,
multiple_of=256,
ffn_dim_multiplier=None,
device=device,
dtype=dtype,
operations=operations,
)
# MLP for text not needed in last block.
if self.update_y:
mlp_hidden_dim_y = int(hidden_size_y * mlp_ratio_y)
self.mlp_y = FeedForward(
in_features=hidden_size_y,
hidden_size=mlp_hidden_dim_y,
multiple_of=256,
ffn_dim_multiplier=None,
device=device,
dtype=dtype,
operations=operations,
)
def forward(
self,
x: torch.Tensor,
c: torch.Tensor,
y: torch.Tensor,
**attn_kwargs,
):
"""Forward pass of a block.
Args:
x: (B, N, dim) tensor of visual tokens
c: (B, dim) tensor of conditioned features
y: (B, L, dim) tensor of text tokens
num_frames: Number of frames in the video. N = num_frames * num_spatial_tokens
Returns:
x: (B, N, dim) tensor of visual tokens after block
y: (B, L, dim) tensor of text tokens after block
"""
N = x.size(1)
c = F.silu(c)
mod_x = self.mod_x(c)
scale_msa_x, gate_msa_x, scale_mlp_x, gate_mlp_x = mod_x.chunk(4, dim=1)
mod_y = self.mod_y(c)
if self.update_y:
scale_msa_y, gate_msa_y, scale_mlp_y, gate_mlp_y = mod_y.chunk(4, dim=1)
else:
scale_msa_y = mod_y
# Self-attention block.
x_attn, y_attn = self.attn(
x,
y,
scale_x=scale_msa_x,
scale_y=scale_msa_y,
**attn_kwargs,
)
assert x_attn.size(1) == N
x = residual_tanh_gated_rmsnorm(x, x_attn, gate_msa_x)
if self.update_y:
y = residual_tanh_gated_rmsnorm(y, y_attn, gate_msa_y)
# MLP block.
x = self.ff_block_x(x, scale_mlp_x, gate_mlp_x)
if self.update_y:
y = self.ff_block_y(y, scale_mlp_y, gate_mlp_y)
return x, y
def ff_block_x(self, x, scale_x, gate_x):
x_mod = modulated_rmsnorm(x, scale_x)
x_res = self.mlp_x(x_mod)
x = residual_tanh_gated_rmsnorm(x, x_res, gate_x) # Sandwich norm
return x
def ff_block_y(self, y, scale_y, gate_y):
y_mod = modulated_rmsnorm(y, scale_y)
y_res = self.mlp_y(y_mod)
y = residual_tanh_gated_rmsnorm(y, y_res, gate_y) # Sandwich norm
return y
class FinalLayer(nn.Module):
"""
The final layer of DiT.
"""
def __init__(
self,
hidden_size,
patch_size,
out_channels,
device: Optional[torch.device] = None,
dtype=None,
operations=None,
):
super().__init__()
self.norm_final = operations.LayerNorm(
hidden_size, elementwise_affine=False, eps=1e-6, device=device, dtype=dtype
)
self.mod = operations.Linear(hidden_size, 2 * hidden_size, device=device, dtype=dtype)
self.linear = operations.Linear(
hidden_size, patch_size * patch_size * out_channels, device=device, dtype=dtype
)
def forward(self, x, c):
c = F.silu(c)
shift, scale = self.mod(c).chunk(2, dim=1)
x = modulate(self.norm_final(x), shift, scale)
x = self.linear(x)
return x
class AsymmDiTJoint(nn.Module):
"""
Diffusion model with a Transformer backbone.
Ingests text embeddings instead of a label.
"""
def __init__(
self,
*,
patch_size=2,
in_channels=4,
hidden_size_x=1152,
hidden_size_y=1152,
depth=48,
num_heads=16,
mlp_ratio_x=8.0,
mlp_ratio_y=4.0,
use_t5: bool = False,
t5_feat_dim: int = 4096,
t5_token_length: int = 256,
learn_sigma=True,
patch_embed_bias: bool = True,
timestep_mlp_bias: bool = True,
attend_to_padding: bool = False,
timestep_scale: Optional[float] = None,
use_extended_posenc: bool = False,
posenc_preserve_area: bool = False,
rope_theta: float = 10000.0,
image_model=None,
device: Optional[torch.device] = None,
dtype=None,
operations=None,
**block_kwargs,
):
super().__init__()
self.dtype = dtype
self.learn_sigma = learn_sigma
self.in_channels = in_channels
self.out_channels = in_channels * 2 if learn_sigma else in_channels
self.patch_size = patch_size
self.num_heads = num_heads
self.hidden_size_x = hidden_size_x
self.hidden_size_y = hidden_size_y
self.head_dim = (
hidden_size_x // num_heads
) # Head dimension and count is determined by visual.
self.attend_to_padding = attend_to_padding
self.use_extended_posenc = use_extended_posenc
self.posenc_preserve_area = posenc_preserve_area
self.use_t5 = use_t5
self.t5_token_length = t5_token_length
self.t5_feat_dim = t5_feat_dim
self.rope_theta = (
rope_theta # Scaling factor for frequency computation for temporal RoPE.
)
self.x_embedder = PatchEmbed(
patch_size=patch_size,
in_chans=in_channels,
embed_dim=hidden_size_x,
bias=patch_embed_bias,
dtype=dtype,
device=device,
operations=operations
)
# Conditionings
# Timestep
self.t_embedder = TimestepEmbedder(
hidden_size_x, bias=timestep_mlp_bias, timestep_scale=timestep_scale, dtype=dtype, device=device, operations=operations
)
if self.use_t5:
# Caption Pooling (T5)
self.t5_y_embedder = AttentionPool(
t5_feat_dim, num_heads=8, output_dim=hidden_size_x, dtype=dtype, device=device, operations=operations
)
# Dense Embedding Projection (T5)
self.t5_yproj = operations.Linear(
t5_feat_dim, hidden_size_y, bias=True, dtype=dtype, device=device
)
# Initialize pos_frequencies as an empty parameter.
self.pos_frequencies = nn.Parameter(
torch.empty(3, self.num_heads, self.head_dim // 2, dtype=dtype, device=device)
)
assert not self.attend_to_padding
# for depth 48:
# b = 0: AsymmetricJointBlock, update_y=True
# b = 1: AsymmetricJointBlock, update_y=True
# ...
# b = 46: AsymmetricJointBlock, update_y=True
# b = 47: AsymmetricJointBlock, update_y=False. No need to update text features.
blocks = []
for b in range(depth):
# Joint multi-modal block
update_y = b < depth - 1
block = AsymmetricJointBlock(
hidden_size_x,
hidden_size_y,
num_heads,
mlp_ratio_x=mlp_ratio_x,
mlp_ratio_y=mlp_ratio_y,
update_y=update_y,
attend_to_padding=attend_to_padding,
device=device,
dtype=dtype,
operations=operations,
**block_kwargs,
)
blocks.append(block)
self.blocks = nn.ModuleList(blocks)
self.final_layer = FinalLayer(
hidden_size_x, patch_size, self.out_channels, dtype=dtype, device=device, operations=operations
)
def embed_x(self, x: torch.Tensor) -> torch.Tensor:
"""
Args:
x: (B, C=12, T, H, W) tensor of visual tokens
Returns:
x: (B, C=3072, N) tensor of visual tokens with positional embedding.
"""
return self.x_embedder(x) # Convert BcTHW to BCN
def prepare(
self,
x: torch.Tensor,
sigma: torch.Tensor,
t5_feat: torch.Tensor,
t5_mask: torch.Tensor,
):
"""Prepare input and conditioning embeddings."""
# Visual patch embeddings with positional encoding.
T, H, W = x.shape[-3:]
pH, pW = H // self.patch_size, W // self.patch_size
x = self.embed_x(x) # (B, N, D), where N = T * H * W / patch_size ** 2
assert x.ndim == 3
B = x.size(0)
pH, pW = H // self.patch_size, W // self.patch_size
N = T * pH * pW
assert x.size(1) == N
pos = create_position_matrix(
T, pH=pH, pW=pW, device=x.device, dtype=torch.float32
) # (N, 3)
rope_cos, rope_sin = compute_mixed_rotation(
freqs=comfy.ops.cast_to(self.pos_frequencies, dtype=x.dtype, device=x.device), pos=pos
) # Each are (N, num_heads, dim // 2)
c_t = self.t_embedder(1 - sigma, out_dtype=x.dtype) # (B, D)
t5_y_pool = self.t5_y_embedder(t5_feat, t5_mask) # (B, D)
c = c_t + t5_y_pool
y_feat = self.t5_yproj(t5_feat) # (B, L, t5_feat_dim) --> (B, L, D)
return x, c, y_feat, rope_cos, rope_sin
def forward(
self,
x: torch.Tensor,
timestep: torch.Tensor,
context: List[torch.Tensor],
attention_mask: List[torch.Tensor],
num_tokens=256,
packed_indices: Dict[str, torch.Tensor] = None,
rope_cos: torch.Tensor = None,
rope_sin: torch.Tensor = None,
control=None, **kwargs
):
y_feat = context
y_mask = attention_mask
sigma = timestep
"""Forward pass of DiT.
Args:
x: (B, C, T, H, W) tensor of spatial inputs (images or latent representations of images)
sigma: (B,) tensor of noise standard deviations
y_feat: List((B, L, y_feat_dim) tensor of caption token features. For SDXL text encoders: L=77, y_feat_dim=2048)
y_mask: List((B, L) boolean tensor indicating which tokens are not padding)
packed_indices: Dict with keys for Flash Attention. Result of compute_packed_indices.
"""
B, _, T, H, W = x.shape
x, c, y_feat, rope_cos, rope_sin = self.prepare(
x, sigma, y_feat, y_mask
)
del y_mask
for i, block in enumerate(self.blocks):
x, y_feat = block(
x,
c,
y_feat,
rope_cos=rope_cos,
rope_sin=rope_sin,
crop_y=num_tokens,
) # (B, M, D), (B, L, D)
del y_feat # Final layers don't use dense text features.
x = self.final_layer(x, c) # (B, M, patch_size ** 2 * out_channels)
x = rearrange(
x,
"B (T hp wp) (p1 p2 c) -> B c T (hp p1) (wp p2)",
T=T,
hp=H // self.patch_size,
wp=W // self.patch_size,
p1=self.patch_size,
p2=self.patch_size,
c=self.out_channels,
)
return -x

View File

@@ -0,0 +1,164 @@
#original code from https://github.com/genmoai/models under apache 2.0 license
#adapted to ComfyUI
import collections.abc
import math
from itertools import repeat
from typing import Callable, Optional
import torch
import torch.nn as nn
import torch.nn.functional as F
from einops import rearrange
import comfy.ldm.common_dit
# From PyTorch internals
def _ntuple(n):
def parse(x):
if isinstance(x, collections.abc.Iterable) and not isinstance(x, str):
return tuple(x)
return tuple(repeat(x, n))
return parse
to_2tuple = _ntuple(2)
class TimestepEmbedder(nn.Module):
def __init__(
self,
hidden_size: int,
frequency_embedding_size: int = 256,
*,
bias: bool = True,
timestep_scale: Optional[float] = None,
dtype=None,
device=None,
operations=None,
):
super().__init__()
self.mlp = nn.Sequential(
operations.Linear(frequency_embedding_size, hidden_size, bias=bias, dtype=dtype, device=device),
nn.SiLU(),
operations.Linear(hidden_size, hidden_size, bias=bias, dtype=dtype, device=device),
)
self.frequency_embedding_size = frequency_embedding_size
self.timestep_scale = timestep_scale
@staticmethod
def timestep_embedding(t, dim, max_period=10000):
half = dim // 2
freqs = torch.arange(start=0, end=half, dtype=torch.float32, device=t.device)
freqs.mul_(-math.log(max_period) / half).exp_()
args = t[:, None].float() * freqs[None]
embedding = torch.cat([torch.cos(args), torch.sin(args)], dim=-1)
if dim % 2:
embedding = torch.cat(
[embedding, torch.zeros_like(embedding[:, :1])], dim=-1
)
return embedding
def forward(self, t, out_dtype):
if self.timestep_scale is not None:
t = t * self.timestep_scale
t_freq = self.timestep_embedding(t, self.frequency_embedding_size).to(dtype=out_dtype)
t_emb = self.mlp(t_freq)
return t_emb
class FeedForward(nn.Module):
def __init__(
self,
in_features: int,
hidden_size: int,
multiple_of: int,
ffn_dim_multiplier: Optional[float],
device: Optional[torch.device] = None,
dtype=None,
operations=None,
):
super().__init__()
# keep parameter count and computation constant compared to standard FFN
hidden_size = int(2 * hidden_size / 3)
# custom dim factor multiplier
if ffn_dim_multiplier is not None:
hidden_size = int(ffn_dim_multiplier * hidden_size)
hidden_size = multiple_of * ((hidden_size + multiple_of - 1) // multiple_of)
self.hidden_dim = hidden_size
self.w1 = operations.Linear(in_features, 2 * hidden_size, bias=False, device=device, dtype=dtype)
self.w2 = operations.Linear(hidden_size, in_features, bias=False, device=device, dtype=dtype)
def forward(self, x):
x, gate = self.w1(x).chunk(2, dim=-1)
x = self.w2(F.silu(x) * gate)
return x
class PatchEmbed(nn.Module):
def __init__(
self,
patch_size: int = 16,
in_chans: int = 3,
embed_dim: int = 768,
norm_layer: Optional[Callable] = None,
flatten: bool = True,
bias: bool = True,
dynamic_img_pad: bool = False,
dtype=None,
device=None,
operations=None,
):
super().__init__()
self.patch_size = to_2tuple(patch_size)
self.flatten = flatten
self.dynamic_img_pad = dynamic_img_pad
self.proj = operations.Conv2d(
in_chans,
embed_dim,
kernel_size=patch_size,
stride=patch_size,
bias=bias,
device=device,
dtype=dtype,
)
assert norm_layer is None
self.norm = (
norm_layer(embed_dim, device=device) if norm_layer else nn.Identity()
)
def forward(self, x):
B, _C, T, H, W = x.shape
if not self.dynamic_img_pad:
assert H % self.patch_size[0] == 0, f"Input height ({H}) should be divisible by patch size ({self.patch_size[0]})."
assert W % self.patch_size[1] == 0, f"Input width ({W}) should be divisible by patch size ({self.patch_size[1]})."
else:
pad_h = (self.patch_size[0] - H % self.patch_size[0]) % self.patch_size[0]
pad_w = (self.patch_size[1] - W % self.patch_size[1]) % self.patch_size[1]
x = F.pad(x, (0, pad_w, 0, pad_h))
x = rearrange(x, "B C T H W -> (B T) C H W", B=B, T=T)
x = comfy.ldm.common_dit.pad_to_patch_size(x, self.patch_size, padding_mode='circular')
x = self.proj(x)
# Flatten temporal and spatial dimensions.
if not self.flatten:
raise NotImplementedError("Must flatten output.")
x = rearrange(x, "(B T) C H W -> B (T H W) C", B=B, T=T)
x = self.norm(x)
return x
class RMSNorm(torch.nn.Module):
def __init__(self, hidden_size, eps=1e-5, device=None, dtype=None):
super().__init__()
self.eps = eps
self.weight = torch.nn.Parameter(torch.empty(hidden_size, device=device, dtype=dtype))
self.register_parameter("bias", None)
def forward(self, x):
return comfy.ldm.common_dit.rms_norm(x, self.weight, self.eps)

View File

@@ -0,0 +1,88 @@
#original code from https://github.com/genmoai/models under apache 2.0 license
# import functools
import math
import torch
def centers(start: float, stop, num, dtype=None, device=None):
"""linspace through bin centers.
Args:
start (float): Start of the range.
stop (float): End of the range.
num (int): Number of points.
dtype (torch.dtype): Data type of the points.
device (torch.device): Device of the points.
Returns:
centers (Tensor): Centers of the bins. Shape: (num,).
"""
edges = torch.linspace(start, stop, num + 1, dtype=dtype, device=device)
return (edges[:-1] + edges[1:]) / 2
# @functools.lru_cache(maxsize=1)
def create_position_matrix(
T: int,
pH: int,
pW: int,
device: torch.device,
dtype: torch.dtype,
*,
target_area: float = 36864,
):
"""
Args:
T: int - Temporal dimension
pH: int - Height dimension after patchify
pW: int - Width dimension after patchify
Returns:
pos: [T * pH * pW, 3] - position matrix
"""
# Create 1D tensors for each dimension
t = torch.arange(T, dtype=dtype)
# Positionally interpolate to area 36864.
# (3072x3072 frame with 16x16 patches = 192x192 latents).
# This automatically scales rope positions when the resolution changes.
# We use a large target area so the model is more sensitive
# to changes in the learned pos_frequencies matrix.
scale = math.sqrt(target_area / (pW * pH))
w = centers(-pW * scale / 2, pW * scale / 2, pW)
h = centers(-pH * scale / 2, pH * scale / 2, pH)
# Use meshgrid to create 3D grids
grid_t, grid_h, grid_w = torch.meshgrid(t, h, w, indexing="ij")
# Stack and reshape the grids.
pos = torch.stack([grid_t, grid_h, grid_w], dim=-1) # [T, pH, pW, 3]
pos = pos.view(-1, 3) # [T * pH * pW, 3]
pos = pos.to(dtype=dtype, device=device)
return pos
def compute_mixed_rotation(
freqs: torch.Tensor,
pos: torch.Tensor,
):
"""
Project each 3-dim position into per-head, per-head-dim 1D frequencies.
Args:
freqs: [3, num_heads, num_freqs] - learned rotation frequency (for t, row, col) for each head position
pos: [N, 3] - position of each token
num_heads: int
Returns:
freqs_cos: [N, num_heads, num_freqs] - cosine components
freqs_sin: [N, num_heads, num_freqs] - sine components
"""
assert freqs.ndim == 3
freqs_sum = torch.einsum("Nd,dhf->Nhf", pos.to(freqs), freqs)
freqs_cos = torch.cos(freqs_sum)
freqs_sin = torch.sin(freqs_sum)
return freqs_cos, freqs_sin

View File

@@ -0,0 +1,34 @@
#original code from https://github.com/genmoai/models under apache 2.0 license
# Based on Llama3 Implementation.
import torch
def apply_rotary_emb_qk_real(
xqk: torch.Tensor,
freqs_cos: torch.Tensor,
freqs_sin: torch.Tensor,
) -> torch.Tensor:
"""
Apply rotary embeddings to input tensors using the given frequency tensor without complex numbers.
Args:
xqk (torch.Tensor): Query and/or Key tensors to apply rotary embeddings. Shape: (B, S, *, num_heads, D)
Can be either just query or just key, or both stacked along some batch or * dim.
freqs_cos (torch.Tensor): Precomputed cosine frequency tensor.
freqs_sin (torch.Tensor): Precomputed sine frequency tensor.
Returns:
torch.Tensor: The input tensor with rotary embeddings applied.
"""
# Split the last dimension into even and odd parts
xqk_even = xqk[..., 0::2]
xqk_odd = xqk[..., 1::2]
# Apply rotation
cos_part = (xqk_even * freqs_cos - xqk_odd * freqs_sin).type_as(xqk)
sin_part = (xqk_even * freqs_sin + xqk_odd * freqs_cos).type_as(xqk)
# Interleave the results back into the original shape
out = torch.stack([cos_part, sin_part], dim=-1).flatten(-2)
return out

View File

@@ -0,0 +1,102 @@
#original code from https://github.com/genmoai/models under apache 2.0 license
#adapted to ComfyUI
from typing import Optional, Tuple
import torch
import torch.nn as nn
import torch.nn.functional as F
def modulate(x, shift, scale):
return x * (1 + scale.unsqueeze(1)) + shift.unsqueeze(1)
def pool_tokens(x: torch.Tensor, mask: torch.Tensor, *, keepdim=False) -> torch.Tensor:
"""
Pool tokens in x using mask.
NOTE: We assume x does not require gradients.
Args:
x: (B, L, D) tensor of tokens.
mask: (B, L) boolean tensor indicating which tokens are not padding.
Returns:
pooled: (B, D) tensor of pooled tokens.
"""
assert x.size(1) == mask.size(1) # Expected mask to have same length as tokens.
assert x.size(0) == mask.size(0) # Expected mask to have same batch size as tokens.
mask = mask[:, :, None].to(dtype=x.dtype)
mask = mask / mask.sum(dim=1, keepdim=True).clamp(min=1)
pooled = (x * mask).sum(dim=1, keepdim=keepdim)
return pooled
class AttentionPool(nn.Module):
def __init__(
self,
embed_dim: int,
num_heads: int,
output_dim: int = None,
device: Optional[torch.device] = None,
dtype=None,
operations=None,
):
"""
Args:
spatial_dim (int): Number of tokens in sequence length.
embed_dim (int): Dimensionality of input tokens.
num_heads (int): Number of attention heads.
output_dim (int): Dimensionality of output tokens. Defaults to embed_dim.
"""
super().__init__()
self.num_heads = num_heads
self.to_kv = operations.Linear(embed_dim, 2 * embed_dim, device=device, dtype=dtype)
self.to_q = operations.Linear(embed_dim, embed_dim, device=device, dtype=dtype)
self.to_out = operations.Linear(embed_dim, output_dim or embed_dim, device=device, dtype=dtype)
def forward(self, x, mask):
"""
Args:
x (torch.Tensor): (B, L, D) tensor of input tokens.
mask (torch.Tensor): (B, L) boolean tensor indicating which tokens are not padding.
NOTE: We assume x does not require gradients.
Returns:
x (torch.Tensor): (B, D) tensor of pooled tokens.
"""
D = x.size(2)
# Construct attention mask, shape: (B, 1, num_queries=1, num_keys=1+L).
attn_mask = mask[:, None, None, :].bool() # (B, 1, 1, L).
attn_mask = F.pad(attn_mask, (1, 0), value=True) # (B, 1, 1, 1+L).
# Average non-padding token features. These will be used as the query.
x_pool = pool_tokens(x, mask, keepdim=True) # (B, 1, D)
# Concat pooled features to input sequence.
x = torch.cat([x_pool, x], dim=1) # (B, L+1, D)
# Compute queries, keys, values. Only the mean token is used to create a query.
kv = self.to_kv(x) # (B, L+1, 2 * D)
q = self.to_q(x[:, 0]) # (B, D)
# Extract heads.
head_dim = D // self.num_heads
kv = kv.unflatten(2, (2, self.num_heads, head_dim)) # (B, 1+L, 2, H, head_dim)
kv = kv.transpose(1, 3) # (B, H, 2, 1+L, head_dim)
k, v = kv.unbind(2) # (B, H, 1+L, head_dim)
q = q.unflatten(1, (self.num_heads, head_dim)) # (B, H, head_dim)
q = q.unsqueeze(2) # (B, H, 1, head_dim)
# Compute attention.
x = F.scaled_dot_product_attention(
q, k, v, attn_mask=attn_mask, dropout_p=0.0
) # (B, H, 1, head_dim)
# Concatenate heads and run output.
x = x.squeeze(2).flatten(1, 2) # (B, D = H * head_dim)
x = self.to_out(x)
return x