Files
ai-toolkit/extensions_built_in/diffusion_models/boogu_image/src/rope.py
2026-06-18 15:05:49 -06:00

245 lines
8.4 KiB
Python

# Vendored from the Boogu-Image repository (boogu/models/transformers/rope.py).
# Original work: Copyright 2025 BAAI / OmniGen2 / HuggingFace. Apache-2.0.
#
# Only the double-stream rotary embedder (the one the transformer uses) and the
# ``get_freqs_cis`` precompute helper are kept. The MPS-specific branch is
# preserved verbatim.
from typing import List, Tuple
import torch
import torch.nn as nn
from diffusers.models.embeddings import get_1d_rotary_pos_embed
from einops import repeat
def get_freqs_cis(
axes_dim: Tuple[int, int, int], axes_lens: Tuple[int, int, int], theta: int
) -> List[torch.Tensor]:
"""Precompute the per-axis rotary frequency tables (done once per resolution)."""
freqs_cis = []
freqs_dtype = torch.float32 if torch.backends.mps.is_available() else torch.float64
for d, e in zip(axes_dim, axes_lens):
emb = get_1d_rotary_pos_embed(d, e, theta=theta, freqs_dtype=freqs_dtype)
freqs_cis.append(emb)
return freqs_cis
class BooguImageDoubleStreamRotaryPosEmbed(nn.Module):
def __init__(
self,
theta: int,
axes_dim: Tuple[int, int, int],
axes_lens: Tuple[int, int, int] = (300, 512, 512),
patch_size: int = 2,
):
super().__init__()
self.theta = theta
self.axes_dim = axes_dim
self.axes_lens = axes_lens
self.patch_size = patch_size
@staticmethod
def get_freqs_cis(
axes_dim: Tuple[int, int, int], axes_lens: Tuple[int, int, int], theta: int
) -> List[torch.Tensor]:
return get_freqs_cis(axes_dim, axes_lens, theta)
def _get_freqs_cis(self, freqs_cis, ids: torch.Tensor) -> torch.Tensor:
device = ids.device
if ids.device.type == "mps":
ids = ids.to("cpu")
result = []
for i in range(len(self.axes_dim)):
freqs = freqs_cis[i].to(ids.device)
index = ids[:, :, i : i + 1].repeat(1, 1, freqs.shape[-1]).to(torch.int64)
result.append(
torch.gather(
freqs.unsqueeze(0).repeat(index.shape[0], 1, 1), dim=1, index=index
)
)
return torch.cat(result, dim=-1).to(device)
def forward(
self,
freqs_cis,
attention_mask,
l_effective_ref_img_len,
l_effective_img_len,
ref_img_sizes,
img_sizes,
device,
):
batch_size = len(attention_mask)
p = self.patch_size
encoder_seq_len = attention_mask.shape[1]
l_effective_cap_len = attention_mask.sum(dim=1).tolist()
seq_lengths = [
cap_len + sum(ref_img_len) + img_len
for cap_len, ref_img_len, img_len in zip(
l_effective_cap_len, l_effective_ref_img_len, l_effective_img_len
)
]
max_seq_len = max(seq_lengths)
max_ref_img_len = max(
[sum(ref_img_len) for ref_img_len in l_effective_ref_img_len]
)
max_img_len = max(l_effective_img_len)
# Create position IDs
position_ids = torch.zeros(
batch_size, max_seq_len, 3, dtype=torch.int32, device=device
)
for i, (cap_seq_len, seq_len) in enumerate(
zip(l_effective_cap_len, seq_lengths)
):
# add text position ids
position_ids[i, :cap_seq_len] = repeat(
torch.arange(cap_seq_len, dtype=torch.int32, device=device), "l -> l 3"
)
pe_shift = cap_seq_len
pe_shift_len = cap_seq_len
if ref_img_sizes[i] is not None:
for ref_img_size, ref_img_len in zip(
ref_img_sizes[i], l_effective_ref_img_len[i]
):
H, W = ref_img_size
ref_H_tokens, ref_W_tokens = H // p, W // p
assert ref_H_tokens * ref_W_tokens == ref_img_len
row_ids = repeat(
torch.arange(ref_H_tokens, dtype=torch.int32, device=device),
"h -> h w",
w=ref_W_tokens,
).flatten()
col_ids = repeat(
torch.arange(ref_W_tokens, dtype=torch.int32, device=device),
"w -> h w",
h=ref_H_tokens,
).flatten()
position_ids[i, pe_shift_len : pe_shift_len + ref_img_len, 0] = (
pe_shift
)
position_ids[i, pe_shift_len : pe_shift_len + ref_img_len, 1] = (
row_ids
)
position_ids[i, pe_shift_len : pe_shift_len + ref_img_len, 2] = (
col_ids
)
pe_shift += max(ref_H_tokens, ref_W_tokens)
pe_shift_len += ref_img_len
H, W = img_sizes[i]
H_tokens, W_tokens = H // p, W // p
assert H_tokens * W_tokens == l_effective_img_len[i]
row_ids = repeat(
torch.arange(H_tokens, dtype=torch.int32, device=device),
"h -> h w",
w=W_tokens,
).flatten()
col_ids = repeat(
torch.arange(W_tokens, dtype=torch.int32, device=device),
"w -> h w",
h=H_tokens,
).flatten()
assert pe_shift_len + l_effective_img_len[i] == seq_len
position_ids[i, pe_shift_len:seq_len, 0] = pe_shift
position_ids[i, pe_shift_len:seq_len, 1] = row_ids
position_ids[i, pe_shift_len:seq_len, 2] = col_ids
# Get combined rotary embeddings
freqs_cis = self._get_freqs_cis(freqs_cis, position_ids)
# create separate rotary embeddings for captions and images
cap_freqs_cis = torch.zeros(
batch_size,
encoder_seq_len,
freqs_cis.shape[-1],
device=device,
dtype=freqs_cis.dtype,
)
ref_img_freqs_cis = torch.zeros(
batch_size,
max_ref_img_len,
freqs_cis.shape[-1],
device=device,
dtype=freqs_cis.dtype,
)
img_freqs_cis = torch.zeros(
batch_size,
max_img_len,
freqs_cis.shape[-1],
device=device,
dtype=freqs_cis.dtype,
)
# Calculate combined image sequence lengths (ref_img + img) for each sample
combined_img_seq_lengths = [
sum(ref_img_len) + img_len
for ref_img_len, img_len in zip(
l_effective_ref_img_len, l_effective_img_len
)
]
max_combined_img_len = max(combined_img_seq_lengths)
# Create combined image rotary embeddings
combined_img_freqs_cis = torch.zeros(
batch_size,
max_combined_img_len,
freqs_cis.shape[-1],
device=device,
dtype=freqs_cis.dtype,
)
for i, (cap_seq_len, ref_img_len, img_len, seq_len) in enumerate(
zip(
l_effective_cap_len,
l_effective_ref_img_len,
l_effective_img_len,
seq_lengths,
)
):
cap_freqs_cis[i, :cap_seq_len] = freqs_cis[i, :cap_seq_len]
ref_img_freqs_cis[i, : sum(ref_img_len)] = freqs_cis[
i, cap_seq_len : cap_seq_len + sum(ref_img_len)
]
img_freqs_cis[i, :img_len] = freqs_cis[
i,
cap_seq_len + sum(ref_img_len) : cap_seq_len
+ sum(ref_img_len)
+ img_len,
]
# Combined image rotary embeddings: ref_img + img (same order as img_patch_embed_and_refine)
combined_img_freqs_cis[i, : sum(ref_img_len)] = freqs_cis[
i, cap_seq_len : cap_seq_len + sum(ref_img_len)
]
combined_img_freqs_cis[i, sum(ref_img_len) : sum(ref_img_len) + img_len] = (
freqs_cis[
i,
cap_seq_len + sum(ref_img_len) : cap_seq_len
+ sum(ref_img_len)
+ img_len,
]
)
return (
cap_freqs_cis,
ref_img_freqs_cis,
img_freqs_cis,
freqs_cis,
l_effective_cap_len,
seq_lengths,
combined_img_freqs_cis,
combined_img_seq_lengths,
)