This commit is contained in:
lllyasviel
2024-01-24 10:27:44 -08:00
parent 19c95de8eb
commit 5ecc9e83bd
142 changed files with 136897 additions and 0 deletions

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import torch
# import pytorch_lightning as pl
import torch.nn.functional as F
from contextlib import contextmanager
from typing import Any, Dict, List, Optional, Tuple, Union
from ldm_patched.ldm.modules.distributions.distributions import DiagonalGaussianDistribution
from ldm_patched.ldm.util import instantiate_from_config
from ldm_patched.ldm.modules.ema import LitEma
import ldm_patched.modules.ops
class DiagonalGaussianRegularizer(torch.nn.Module):
def __init__(self, sample: bool = True):
super().__init__()
self.sample = sample
def get_trainable_parameters(self) -> Any:
yield from ()
def forward(self, z: torch.Tensor) -> Tuple[torch.Tensor, dict]:
log = dict()
posterior = DiagonalGaussianDistribution(z)
if self.sample:
z = posterior.sample()
else:
z = posterior.mode()
kl_loss = posterior.kl()
kl_loss = torch.sum(kl_loss) / kl_loss.shape[0]
log["kl_loss"] = kl_loss
return z, log
class AbstractAutoencoder(torch.nn.Module):
"""
This is the base class for all autoencoders, including image autoencoders, image autoencoders with discriminators,
unCLIP models, etc. Hence, it is fairly general, and specific features
(e.g. discriminator training, encoding, decoding) must be implemented in subclasses.
"""
def __init__(
self,
ema_decay: Union[None, float] = None,
monitor: Union[None, str] = None,
input_key: str = "jpg",
**kwargs,
):
super().__init__()
self.input_key = input_key
self.use_ema = ema_decay is not None
if monitor is not None:
self.monitor = monitor
if self.use_ema:
self.model_ema = LitEma(self, decay=ema_decay)
logpy.info(f"Keeping EMAs of {len(list(self.model_ema.buffers()))}.")
def get_input(self, batch) -> Any:
raise NotImplementedError()
def on_train_batch_end(self, *args, **kwargs):
# for EMA computation
if self.use_ema:
self.model_ema(self)
@contextmanager
def ema_scope(self, context=None):
if self.use_ema:
self.model_ema.store(self.parameters())
self.model_ema.copy_to(self)
if context is not None:
logpy.info(f"{context}: Switched to EMA weights")
try:
yield None
finally:
if self.use_ema:
self.model_ema.restore(self.parameters())
if context is not None:
logpy.info(f"{context}: Restored training weights")
def encode(self, *args, **kwargs) -> torch.Tensor:
raise NotImplementedError("encode()-method of abstract base class called")
def decode(self, *args, **kwargs) -> torch.Tensor:
raise NotImplementedError("decode()-method of abstract base class called")
def instantiate_optimizer_from_config(self, params, lr, cfg):
logpy.info(f"loading >>> {cfg['target']} <<< optimizer from config")
return get_obj_from_str(cfg["target"])(
params, lr=lr, **cfg.get("params", dict())
)
def configure_optimizers(self) -> Any:
raise NotImplementedError()
class AutoencodingEngine(AbstractAutoencoder):
"""
Base class for all image autoencoders that we train, like VQGAN or AutoencoderKL
(we also restore them explicitly as special cases for legacy reasons).
Regularizations such as KL or VQ are moved to the regularizer class.
"""
def __init__(
self,
*args,
encoder_config: Dict,
decoder_config: Dict,
regularizer_config: Dict,
**kwargs,
):
super().__init__(*args, **kwargs)
self.encoder: torch.nn.Module = instantiate_from_config(encoder_config)
self.decoder: torch.nn.Module = instantiate_from_config(decoder_config)
self.regularization: AbstractRegularizer = instantiate_from_config(
regularizer_config
)
def get_last_layer(self):
return self.decoder.get_last_layer()
def encode(
self,
x: torch.Tensor,
return_reg_log: bool = False,
unregularized: bool = False,
) -> Union[torch.Tensor, Tuple[torch.Tensor, dict]]:
z = self.encoder(x)
if unregularized:
return z, dict()
z, reg_log = self.regularization(z)
if return_reg_log:
return z, reg_log
return z
def decode(self, z: torch.Tensor, **kwargs) -> torch.Tensor:
x = self.decoder(z, **kwargs)
return x
def forward(
self, x: torch.Tensor, **additional_decode_kwargs
) -> Tuple[torch.Tensor, torch.Tensor, dict]:
z, reg_log = self.encode(x, return_reg_log=True)
dec = self.decode(z, **additional_decode_kwargs)
return z, dec, reg_log
class AutoencodingEngineLegacy(AutoencodingEngine):
def __init__(self, embed_dim: int, **kwargs):
self.max_batch_size = kwargs.pop("max_batch_size", None)
ddconfig = kwargs.pop("ddconfig")
super().__init__(
encoder_config={
"target": "ldm_patched.ldm.modules.diffusionmodules.model.Encoder",
"params": ddconfig,
},
decoder_config={
"target": "ldm_patched.ldm.modules.diffusionmodules.model.Decoder",
"params": ddconfig,
},
**kwargs,
)
self.quant_conv = ldm_patched.modules.ops.disable_weight_init.Conv2d(
(1 + ddconfig["double_z"]) * ddconfig["z_channels"],
(1 + ddconfig["double_z"]) * embed_dim,
1,
)
self.post_quant_conv = ldm_patched.modules.ops.disable_weight_init.Conv2d(embed_dim, ddconfig["z_channels"], 1)
self.embed_dim = embed_dim
def get_autoencoder_params(self) -> list:
params = super().get_autoencoder_params()
return params
def encode(
self, x: torch.Tensor, return_reg_log: bool = False
) -> Union[torch.Tensor, Tuple[torch.Tensor, dict]]:
if self.max_batch_size is None:
z = self.encoder(x)
z = self.quant_conv(z)
else:
N = x.shape[0]
bs = self.max_batch_size
n_batches = int(math.ceil(N / bs))
z = list()
for i_batch in range(n_batches):
z_batch = self.encoder(x[i_batch * bs : (i_batch + 1) * bs])
z_batch = self.quant_conv(z_batch)
z.append(z_batch)
z = torch.cat(z, 0)
z, reg_log = self.regularization(z)
if return_reg_log:
return z, reg_log
return z
def decode(self, z: torch.Tensor, **decoder_kwargs) -> torch.Tensor:
if self.max_batch_size is None:
dec = self.post_quant_conv(z)
dec = self.decoder(dec, **decoder_kwargs)
else:
N = z.shape[0]
bs = self.max_batch_size
n_batches = int(math.ceil(N / bs))
dec = list()
for i_batch in range(n_batches):
dec_batch = self.post_quant_conv(z[i_batch * bs : (i_batch + 1) * bs])
dec_batch = self.decoder(dec_batch, **decoder_kwargs)
dec.append(dec_batch)
dec = torch.cat(dec, 0)
return dec
class AutoencoderKL(AutoencodingEngineLegacy):
def __init__(self, **kwargs):
if "lossconfig" in kwargs:
kwargs["loss_config"] = kwargs.pop("lossconfig")
super().__init__(
regularizer_config={
"target": (
"ldm_patched.ldm.models.autoencoder.DiagonalGaussianRegularizer"
)
},
**kwargs,
)

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from inspect import isfunction
import math
import torch
import torch.nn.functional as F
from torch import nn, einsum
from einops import rearrange, repeat
from typing import Optional, Any
from functools import partial
from .diffusionmodules.util import checkpoint, AlphaBlender, timestep_embedding
from .sub_quadratic_attention import efficient_dot_product_attention
from ldm_patched.modules import model_management
if model_management.xformers_enabled():
import xformers
import xformers.ops
from ldm_patched.modules.args_parser import args
import ldm_patched.modules.ops
ops = ldm_patched.modules.ops.disable_weight_init
# CrossAttn precision handling
if args.disable_attention_upcast:
print("disabling upcasting of attention")
_ATTN_PRECISION = "fp16"
else:
_ATTN_PRECISION = "fp32"
def exists(val):
return val is not None
def uniq(arr):
return{el: True for el in arr}.keys()
def default(val, d):
if exists(val):
return val
return d
def max_neg_value(t):
return -torch.finfo(t.dtype).max
def init_(tensor):
dim = tensor.shape[-1]
std = 1 / math.sqrt(dim)
tensor.uniform_(-std, std)
return tensor
# feedforward
class GEGLU(nn.Module):
def __init__(self, dim_in, dim_out, dtype=None, device=None, operations=ops):
super().__init__()
self.proj = operations.Linear(dim_in, dim_out * 2, dtype=dtype, device=device)
def forward(self, x):
x, gate = self.proj(x).chunk(2, dim=-1)
return x * F.gelu(gate)
class FeedForward(nn.Module):
def __init__(self, dim, dim_out=None, mult=4, glu=False, dropout=0., dtype=None, device=None, operations=ops):
super().__init__()
inner_dim = int(dim * mult)
dim_out = default(dim_out, dim)
project_in = nn.Sequential(
operations.Linear(dim, inner_dim, dtype=dtype, device=device),
nn.GELU()
) if not glu else GEGLU(dim, inner_dim, dtype=dtype, device=device, operations=operations)
self.net = nn.Sequential(
project_in,
nn.Dropout(dropout),
operations.Linear(inner_dim, dim_out, dtype=dtype, device=device)
)
def forward(self, x):
return self.net(x)
def Normalize(in_channels, dtype=None, device=None):
return torch.nn.GroupNorm(num_groups=32, num_channels=in_channels, eps=1e-6, affine=True, dtype=dtype, device=device)
def attention_basic(q, k, v, heads, mask=None):
b, _, dim_head = q.shape
dim_head //= heads
scale = dim_head ** -0.5
h = heads
q, k, v = map(
lambda t: t.unsqueeze(3)
.reshape(b, -1, heads, dim_head)
.permute(0, 2, 1, 3)
.reshape(b * heads, -1, dim_head)
.contiguous(),
(q, k, v),
)
# force cast to fp32 to avoid overflowing
if _ATTN_PRECISION =="fp32":
sim = einsum('b i d, b j d -> b i j', q.float(), k.float()) * scale
else:
sim = einsum('b i d, b j d -> b i j', q, k) * scale
del q, k
if exists(mask):
if mask.dtype == torch.bool:
mask = rearrange(mask, 'b ... -> b (...)') #TODO: check if this bool part matches pytorch attention
max_neg_value = -torch.finfo(sim.dtype).max
mask = repeat(mask, 'b j -> (b h) () j', h=h)
sim.masked_fill_(~mask, max_neg_value)
else:
sim += mask
# attention, what we cannot get enough of
sim = sim.softmax(dim=-1)
out = einsum('b i j, b j d -> b i d', sim.to(v.dtype), v)
out = (
out.unsqueeze(0)
.reshape(b, heads, -1, dim_head)
.permute(0, 2, 1, 3)
.reshape(b, -1, heads * dim_head)
)
return out
def attention_sub_quad(query, key, value, heads, mask=None):
b, _, dim_head = query.shape
dim_head //= heads
scale = dim_head ** -0.5
query = query.unsqueeze(3).reshape(b, -1, heads, dim_head).permute(0, 2, 1, 3).reshape(b * heads, -1, dim_head)
value = value.unsqueeze(3).reshape(b, -1, heads, dim_head).permute(0, 2, 1, 3).reshape(b * heads, -1, dim_head)
key = key.unsqueeze(3).reshape(b, -1, heads, dim_head).permute(0, 2, 3, 1).reshape(b * heads, dim_head, -1)
dtype = query.dtype
upcast_attention = _ATTN_PRECISION =="fp32" and query.dtype != torch.float32
if upcast_attention:
bytes_per_token = torch.finfo(torch.float32).bits//8
else:
bytes_per_token = torch.finfo(query.dtype).bits//8
batch_x_heads, q_tokens, _ = query.shape
_, _, k_tokens = key.shape
qk_matmul_size_bytes = batch_x_heads * bytes_per_token * q_tokens * k_tokens
mem_free_total, mem_free_torch = model_management.get_free_memory(query.device, True)
kv_chunk_size_min = None
kv_chunk_size = None
query_chunk_size = None
for x in [4096, 2048, 1024, 512, 256]:
count = mem_free_total / (batch_x_heads * bytes_per_token * x * 4.0)
if count >= k_tokens:
kv_chunk_size = k_tokens
query_chunk_size = x
break
if query_chunk_size is None:
query_chunk_size = 512
hidden_states = efficient_dot_product_attention(
query,
key,
value,
query_chunk_size=query_chunk_size,
kv_chunk_size=kv_chunk_size,
kv_chunk_size_min=kv_chunk_size_min,
use_checkpoint=False,
upcast_attention=upcast_attention,
mask=mask,
)
hidden_states = hidden_states.to(dtype)
hidden_states = hidden_states.unflatten(0, (-1, heads)).transpose(1,2).flatten(start_dim=2)
return hidden_states
def attention_split(q, k, v, heads, mask=None):
b, _, dim_head = q.shape
dim_head //= heads
scale = dim_head ** -0.5
h = heads
q, k, v = map(
lambda t: t.unsqueeze(3)
.reshape(b, -1, heads, dim_head)
.permute(0, 2, 1, 3)
.reshape(b * heads, -1, dim_head)
.contiguous(),
(q, k, v),
)
r1 = torch.zeros(q.shape[0], q.shape[1], v.shape[2], device=q.device, dtype=q.dtype)
mem_free_total = model_management.get_free_memory(q.device)
if _ATTN_PRECISION =="fp32":
element_size = 4
else:
element_size = q.element_size()
gb = 1024 ** 3
tensor_size = q.shape[0] * q.shape[1] * k.shape[1] * element_size
modifier = 3
mem_required = tensor_size * modifier
steps = 1
if mem_required > mem_free_total:
steps = 2**(math.ceil(math.log(mem_required / mem_free_total, 2)))
# print(f"Expected tensor size:{tensor_size/gb:0.1f}GB, cuda free:{mem_free_cuda/gb:0.1f}GB "
# f"torch free:{mem_free_torch/gb:0.1f} total:{mem_free_total/gb:0.1f} steps:{steps}")
if steps > 64:
max_res = math.floor(math.sqrt(math.sqrt(mem_free_total / 2.5)) / 8) * 64
raise RuntimeError(f'Not enough memory, use lower resolution (max approx. {max_res}x{max_res}). '
f'Need: {mem_required/64/gb:0.1f}GB free, Have:{mem_free_total/gb:0.1f}GB free')
# print("steps", steps, mem_required, mem_free_total, modifier, q.element_size(), tensor_size)
first_op_done = False
cleared_cache = False
while True:
try:
slice_size = q.shape[1] // steps if (q.shape[1] % steps) == 0 else q.shape[1]
for i in range(0, q.shape[1], slice_size):
end = i + slice_size
if _ATTN_PRECISION =="fp32":
with torch.autocast(enabled=False, device_type = 'cuda'):
s1 = einsum('b i d, b j d -> b i j', q[:, i:end].float(), k.float()) * scale
else:
s1 = einsum('b i d, b j d -> b i j', q[:, i:end], k) * scale
if mask is not None:
if len(mask.shape) == 2:
s1 += mask[i:end]
else:
s1 += mask[:, i:end]
s2 = s1.softmax(dim=-1).to(v.dtype)
del s1
first_op_done = True
r1[:, i:end] = einsum('b i j, b j d -> b i d', s2, v)
del s2
break
except model_management.OOM_EXCEPTION as e:
if first_op_done == False:
model_management.soft_empty_cache(True)
if cleared_cache == False:
cleared_cache = True
print("out of memory error, emptying cache and trying again")
continue
steps *= 2
if steps > 64:
raise e
print("out of memory error, increasing steps and trying again", steps)
else:
raise e
del q, k, v
r1 = (
r1.unsqueeze(0)
.reshape(b, heads, -1, dim_head)
.permute(0, 2, 1, 3)
.reshape(b, -1, heads * dim_head)
)
return r1
BROKEN_XFORMERS = False
try:
x_vers = xformers.__version__
#I think 0.0.23 is also broken (q with bs bigger than 65535 gives CUDA error)
BROKEN_XFORMERS = x_vers.startswith("0.0.21") or x_vers.startswith("0.0.22") or x_vers.startswith("0.0.23")
except:
pass
def attention_xformers(q, k, v, heads, mask=None):
b, _, dim_head = q.shape
dim_head //= heads
if BROKEN_XFORMERS:
if b * heads > 65535:
return attention_pytorch(q, k, v, heads, mask)
q, k, v = map(
lambda t: t.unsqueeze(3)
.reshape(b, -1, heads, dim_head)
.permute(0, 2, 1, 3)
.reshape(b * heads, -1, dim_head)
.contiguous(),
(q, k, v),
)
if mask is not None:
pad = 8 - q.shape[1] % 8
mask_out = torch.empty([q.shape[0], q.shape[1], q.shape[1] + pad], dtype=q.dtype, device=q.device)
mask_out[:, :, :mask.shape[-1]] = mask
mask = mask_out[:, :, :mask.shape[-1]]
out = xformers.ops.memory_efficient_attention(q, k, v, attn_bias=mask)
out = (
out.unsqueeze(0)
.reshape(b, heads, -1, dim_head)
.permute(0, 2, 1, 3)
.reshape(b, -1, heads * dim_head)
)
return out
def attention_pytorch(q, k, v, heads, mask=None):
b, _, dim_head = q.shape
dim_head //= heads
q, k, v = map(
lambda t: t.view(b, -1, heads, dim_head).transpose(1, 2),
(q, k, v),
)
out = torch.nn.functional.scaled_dot_product_attention(q, k, v, attn_mask=mask, dropout_p=0.0, is_causal=False)
out = (
out.transpose(1, 2).reshape(b, -1, heads * dim_head)
)
return out
optimized_attention = attention_basic
if model_management.xformers_enabled():
print("Using xformers cross attention")
optimized_attention = attention_xformers
elif model_management.pytorch_attention_enabled():
print("Using pytorch cross attention")
optimized_attention = attention_pytorch
else:
if args.attention_split:
print("Using split optimization for cross attention")
optimized_attention = attention_split
else:
print("Using sub quadratic optimization for cross attention, if you have memory or speed issues try using: --attention-split")
optimized_attention = attention_sub_quad
optimized_attention_masked = optimized_attention
def optimized_attention_for_device(device, mask=False, small_input=False):
if small_input:
if model_management.pytorch_attention_enabled():
return attention_pytorch #TODO: need to confirm but this is probably slightly faster for small inputs in all cases
else:
return attention_basic
if device == torch.device("cpu"):
return attention_sub_quad
if mask:
return optimized_attention_masked
return optimized_attention
class CrossAttention(nn.Module):
def __init__(self, query_dim, context_dim=None, heads=8, dim_head=64, dropout=0., dtype=None, device=None, operations=ops):
super().__init__()
inner_dim = dim_head * heads
context_dim = default(context_dim, query_dim)
self.heads = heads
self.dim_head = dim_head
self.to_q = operations.Linear(query_dim, inner_dim, bias=False, dtype=dtype, device=device)
self.to_k = operations.Linear(context_dim, inner_dim, bias=False, dtype=dtype, device=device)
self.to_v = operations.Linear(context_dim, inner_dim, bias=False, dtype=dtype, device=device)
self.to_out = nn.Sequential(operations.Linear(inner_dim, query_dim, dtype=dtype, device=device), nn.Dropout(dropout))
def forward(self, x, context=None, value=None, mask=None):
q = self.to_q(x)
context = default(context, x)
k = self.to_k(context)
if value is not None:
v = self.to_v(value)
del value
else:
v = self.to_v(context)
if mask is None:
out = optimized_attention(q, k, v, self.heads)
else:
out = optimized_attention_masked(q, k, v, self.heads, mask)
return self.to_out(out)
class BasicTransformerBlock(nn.Module):
def __init__(self, dim, n_heads, d_head, dropout=0., context_dim=None, gated_ff=True, checkpoint=True, ff_in=False, inner_dim=None,
disable_self_attn=False, disable_temporal_crossattention=False, switch_temporal_ca_to_sa=False, dtype=None, device=None, operations=ops):
super().__init__()
self.ff_in = ff_in or inner_dim is not None
if inner_dim is None:
inner_dim = dim
self.is_res = inner_dim == dim
if self.ff_in:
self.norm_in = operations.LayerNorm(dim, dtype=dtype, device=device)
self.ff_in = FeedForward(dim, dim_out=inner_dim, dropout=dropout, glu=gated_ff, dtype=dtype, device=device, operations=operations)
self.disable_self_attn = disable_self_attn
self.attn1 = CrossAttention(query_dim=inner_dim, heads=n_heads, dim_head=d_head, dropout=dropout,
context_dim=context_dim if self.disable_self_attn else None, dtype=dtype, device=device, operations=operations) # is a self-attention if not self.disable_self_attn
self.ff = FeedForward(inner_dim, dim_out=dim, dropout=dropout, glu=gated_ff, dtype=dtype, device=device, operations=operations)
if disable_temporal_crossattention:
if switch_temporal_ca_to_sa:
raise ValueError
else:
self.attn2 = None
else:
context_dim_attn2 = None
if not switch_temporal_ca_to_sa:
context_dim_attn2 = context_dim
self.attn2 = CrossAttention(query_dim=inner_dim, context_dim=context_dim_attn2,
heads=n_heads, dim_head=d_head, dropout=dropout, dtype=dtype, device=device, operations=operations) # is self-attn if context is none
self.norm2 = operations.LayerNorm(inner_dim, dtype=dtype, device=device)
self.norm1 = operations.LayerNorm(inner_dim, dtype=dtype, device=device)
self.norm3 = operations.LayerNorm(inner_dim, dtype=dtype, device=device)
self.checkpoint = checkpoint
self.n_heads = n_heads
self.d_head = d_head
self.switch_temporal_ca_to_sa = switch_temporal_ca_to_sa
def forward(self, x, context=None, transformer_options={}):
return checkpoint(self._forward, (x, context, transformer_options), self.parameters(), self.checkpoint)
def _forward(self, x, context=None, transformer_options={}):
extra_options = {}
block = transformer_options.get("block", None)
block_index = transformer_options.get("block_index", 0)
transformer_patches = {}
transformer_patches_replace = {}
for k in transformer_options:
if k == "patches":
transformer_patches = transformer_options[k]
elif k == "patches_replace":
transformer_patches_replace = transformer_options[k]
else:
extra_options[k] = transformer_options[k]
extra_options["n_heads"] = self.n_heads
extra_options["dim_head"] = self.d_head
if self.ff_in:
x_skip = x
x = self.ff_in(self.norm_in(x))
if self.is_res:
x += x_skip
n = self.norm1(x)
if self.disable_self_attn:
context_attn1 = context
else:
context_attn1 = None
value_attn1 = None
if "attn1_patch" in transformer_patches:
patch = transformer_patches["attn1_patch"]
if context_attn1 is None:
context_attn1 = n
value_attn1 = context_attn1
for p in patch:
n, context_attn1, value_attn1 = p(n, context_attn1, value_attn1, extra_options)
if block is not None:
transformer_block = (block[0], block[1], block_index)
else:
transformer_block = None
attn1_replace_patch = transformer_patches_replace.get("attn1", {})
block_attn1 = transformer_block
if block_attn1 not in attn1_replace_patch:
block_attn1 = block
if block_attn1 in attn1_replace_patch:
if context_attn1 is None:
context_attn1 = n
value_attn1 = n
n = self.attn1.to_q(n)
context_attn1 = self.attn1.to_k(context_attn1)
value_attn1 = self.attn1.to_v(value_attn1)
n = attn1_replace_patch[block_attn1](n, context_attn1, value_attn1, extra_options)
n = self.attn1.to_out(n)
else:
n = self.attn1(n, context=context_attn1, value=value_attn1)
if "attn1_output_patch" in transformer_patches:
patch = transformer_patches["attn1_output_patch"]
for p in patch:
n = p(n, extra_options)
x += n
if "middle_patch" in transformer_patches:
patch = transformer_patches["middle_patch"]
for p in patch:
x = p(x, extra_options)
if self.attn2 is not None:
n = self.norm2(x)
if self.switch_temporal_ca_to_sa:
context_attn2 = n
else:
context_attn2 = context
value_attn2 = None
if "attn2_patch" in transformer_patches:
patch = transformer_patches["attn2_patch"]
value_attn2 = context_attn2
for p in patch:
n, context_attn2, value_attn2 = p(n, context_attn2, value_attn2, extra_options)
attn2_replace_patch = transformer_patches_replace.get("attn2", {})
block_attn2 = transformer_block
if block_attn2 not in attn2_replace_patch:
block_attn2 = block
if block_attn2 in attn2_replace_patch:
if value_attn2 is None:
value_attn2 = context_attn2
n = self.attn2.to_q(n)
context_attn2 = self.attn2.to_k(context_attn2)
value_attn2 = self.attn2.to_v(value_attn2)
n = attn2_replace_patch[block_attn2](n, context_attn2, value_attn2, extra_options)
n = self.attn2.to_out(n)
else:
n = self.attn2(n, context=context_attn2, value=value_attn2)
if "attn2_output_patch" in transformer_patches:
patch = transformer_patches["attn2_output_patch"]
for p in patch:
n = p(n, extra_options)
x += n
if self.is_res:
x_skip = x
x = self.ff(self.norm3(x))
if self.is_res:
x += x_skip
return x
class SpatialTransformer(nn.Module):
"""
Transformer block for image-like data.
First, project the input (aka embedding)
and reshape to b, t, d.
Then apply standard transformer action.
Finally, reshape to image
NEW: use_linear for more efficiency instead of the 1x1 convs
"""
def __init__(self, in_channels, n_heads, d_head,
depth=1, dropout=0., context_dim=None,
disable_self_attn=False, use_linear=False,
use_checkpoint=True, dtype=None, device=None, operations=ops):
super().__init__()
if exists(context_dim) and not isinstance(context_dim, list):
context_dim = [context_dim] * depth
self.in_channels = in_channels
inner_dim = n_heads * d_head
self.norm = operations.GroupNorm(num_groups=32, num_channels=in_channels, eps=1e-6, affine=True, dtype=dtype, device=device)
if not use_linear:
self.proj_in = operations.Conv2d(in_channels,
inner_dim,
kernel_size=1,
stride=1,
padding=0, dtype=dtype, device=device)
else:
self.proj_in = operations.Linear(in_channels, inner_dim, dtype=dtype, device=device)
self.transformer_blocks = nn.ModuleList(
[BasicTransformerBlock(inner_dim, n_heads, d_head, dropout=dropout, context_dim=context_dim[d],
disable_self_attn=disable_self_attn, checkpoint=use_checkpoint, dtype=dtype, device=device, operations=operations)
for d in range(depth)]
)
if not use_linear:
self.proj_out = operations.Conv2d(inner_dim,in_channels,
kernel_size=1,
stride=1,
padding=0, dtype=dtype, device=device)
else:
self.proj_out = operations.Linear(in_channels, inner_dim, dtype=dtype, device=device)
self.use_linear = use_linear
def forward(self, x, context=None, transformer_options={}):
# note: if no context is given, cross-attention defaults to self-attention
if not isinstance(context, list):
context = [context] * len(self.transformer_blocks)
b, c, h, w = x.shape
x_in = x
x = self.norm(x)
if not self.use_linear:
x = self.proj_in(x)
x = rearrange(x, 'b c h w -> b (h w) c').contiguous()
if self.use_linear:
x = self.proj_in(x)
for i, block in enumerate(self.transformer_blocks):
transformer_options["block_index"] = i
x = block(x, context=context[i], transformer_options=transformer_options)
if self.use_linear:
x = self.proj_out(x)
x = rearrange(x, 'b (h w) c -> b c h w', h=h, w=w).contiguous()
if not self.use_linear:
x = self.proj_out(x)
return x + x_in
class SpatialVideoTransformer(SpatialTransformer):
def __init__(
self,
in_channels,
n_heads,
d_head,
depth=1,
dropout=0.0,
use_linear=False,
context_dim=None,
use_spatial_context=False,
timesteps=None,
merge_strategy: str = "fixed",
merge_factor: float = 0.5,
time_context_dim=None,
ff_in=False,
checkpoint=False,
time_depth=1,
disable_self_attn=False,
disable_temporal_crossattention=False,
max_time_embed_period: int = 10000,
dtype=None, device=None, operations=ops
):
super().__init__(
in_channels,
n_heads,
d_head,
depth=depth,
dropout=dropout,
use_checkpoint=checkpoint,
context_dim=context_dim,
use_linear=use_linear,
disable_self_attn=disable_self_attn,
dtype=dtype, device=device, operations=operations
)
self.time_depth = time_depth
self.depth = depth
self.max_time_embed_period = max_time_embed_period
time_mix_d_head = d_head
n_time_mix_heads = n_heads
time_mix_inner_dim = int(time_mix_d_head * n_time_mix_heads)
inner_dim = n_heads * d_head
if use_spatial_context:
time_context_dim = context_dim
self.time_stack = nn.ModuleList(
[
BasicTransformerBlock(
inner_dim,
n_time_mix_heads,
time_mix_d_head,
dropout=dropout,
context_dim=time_context_dim,
# timesteps=timesteps,
checkpoint=checkpoint,
ff_in=ff_in,
inner_dim=time_mix_inner_dim,
disable_self_attn=disable_self_attn,
disable_temporal_crossattention=disable_temporal_crossattention,
dtype=dtype, device=device, operations=operations
)
for _ in range(self.depth)
]
)
assert len(self.time_stack) == len(self.transformer_blocks)
self.use_spatial_context = use_spatial_context
self.in_channels = in_channels
time_embed_dim = self.in_channels * 4
self.time_pos_embed = nn.Sequential(
operations.Linear(self.in_channels, time_embed_dim, dtype=dtype, device=device),
nn.SiLU(),
operations.Linear(time_embed_dim, self.in_channels, dtype=dtype, device=device),
)
self.time_mixer = AlphaBlender(
alpha=merge_factor, merge_strategy=merge_strategy
)
def forward(
self,
x: torch.Tensor,
context: Optional[torch.Tensor] = None,
time_context: Optional[torch.Tensor] = None,
timesteps: Optional[int] = None,
image_only_indicator: Optional[torch.Tensor] = None,
transformer_options={}
) -> torch.Tensor:
_, _, h, w = x.shape
x_in = x
spatial_context = None
if exists(context):
spatial_context = context
if self.use_spatial_context:
assert (
context.ndim == 3
), f"n dims of spatial context should be 3 but are {context.ndim}"
if time_context is None:
time_context = context
time_context_first_timestep = time_context[::timesteps]
time_context = repeat(
time_context_first_timestep, "b ... -> (b n) ...", n=h * w
)
elif time_context is not None and not self.use_spatial_context:
time_context = repeat(time_context, "b ... -> (b n) ...", n=h * w)
if time_context.ndim == 2:
time_context = rearrange(time_context, "b c -> b 1 c")
x = self.norm(x)
if not self.use_linear:
x = self.proj_in(x)
x = rearrange(x, "b c h w -> b (h w) c")
if self.use_linear:
x = self.proj_in(x)
num_frames = torch.arange(timesteps, device=x.device)
num_frames = repeat(num_frames, "t -> b t", b=x.shape[0] // timesteps)
num_frames = rearrange(num_frames, "b t -> (b t)")
t_emb = timestep_embedding(num_frames, self.in_channels, repeat_only=False, max_period=self.max_time_embed_period).to(x.dtype)
emb = self.time_pos_embed(t_emb)
emb = emb[:, None, :]
for it_, (block, mix_block) in enumerate(
zip(self.transformer_blocks, self.time_stack)
):
transformer_options["block_index"] = it_
x = block(
x,
context=spatial_context,
transformer_options=transformer_options,
)
x_mix = x
x_mix = x_mix + emb
B, S, C = x_mix.shape
x_mix = rearrange(x_mix, "(b t) s c -> (b s) t c", t=timesteps)
x_mix = mix_block(x_mix, context=time_context) #TODO: transformer_options
x_mix = rearrange(
x_mix, "(b s) t c -> (b t) s c", s=S, b=B // timesteps, c=C, t=timesteps
)
x = self.time_mixer(x_spatial=x, x_temporal=x_mix, image_only_indicator=image_only_indicator)
if self.use_linear:
x = self.proj_out(x)
x = rearrange(x, "b (h w) c -> b c h w", h=h, w=w)
if not self.use_linear:
x = self.proj_out(x)
out = x + x_in
return out

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# pytorch_diffusion + derived encoder decoder
import math
import torch
import torch.nn as nn
import numpy as np
from einops import rearrange
from typing import Optional, Any
from ldm_patched.modules import model_management
import ldm_patched.modules.ops
ops = ldm_patched.modules.ops.disable_weight_init
if model_management.xformers_enabled_vae():
import xformers
import xformers.ops
def get_timestep_embedding(timesteps, embedding_dim):
"""
This matches the implementation in Denoising Diffusion Probabilistic Models:
From Fairseq.
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".
"""
assert len(timesteps.shape) == 1
half_dim = embedding_dim // 2
emb = math.log(10000) / (half_dim - 1)
emb = torch.exp(torch.arange(half_dim, dtype=torch.float32) * -emb)
emb = emb.to(device=timesteps.device)
emb = timesteps.float()[:, None] * emb[None, :]
emb = torch.cat([torch.sin(emb), torch.cos(emb)], dim=1)
if embedding_dim % 2 == 1: # zero pad
emb = torch.nn.functional.pad(emb, (0,1,0,0))
return emb
def nonlinearity(x):
# swish
return x*torch.sigmoid(x)
def Normalize(in_channels, num_groups=32):
return ops.GroupNorm(num_groups=num_groups, num_channels=in_channels, eps=1e-6, affine=True)
class Upsample(nn.Module):
def __init__(self, in_channels, with_conv):
super().__init__()
self.with_conv = with_conv
if self.with_conv:
self.conv = ops.Conv2d(in_channels,
in_channels,
kernel_size=3,
stride=1,
padding=1)
def forward(self, x):
try:
x = torch.nn.functional.interpolate(x, scale_factor=2.0, mode="nearest")
except: #operation not implemented for bf16
b, c, h, w = x.shape
out = torch.empty((b, c, h*2, w*2), dtype=x.dtype, layout=x.layout, device=x.device)
split = 8
l = out.shape[1] // split
for i in range(0, out.shape[1], l):
out[:,i:i+l] = torch.nn.functional.interpolate(x[:,i:i+l].to(torch.float32), scale_factor=2.0, mode="nearest").to(x.dtype)
del x
x = out
if self.with_conv:
x = self.conv(x)
return x
class Downsample(nn.Module):
def __init__(self, in_channels, with_conv):
super().__init__()
self.with_conv = with_conv
if self.with_conv:
# no asymmetric padding in torch conv, must do it ourselves
self.conv = ops.Conv2d(in_channels,
in_channels,
kernel_size=3,
stride=2,
padding=0)
def forward(self, x):
if self.with_conv:
pad = (0,1,0,1)
x = torch.nn.functional.pad(x, pad, mode="constant", value=0)
x = self.conv(x)
else:
x = torch.nn.functional.avg_pool2d(x, kernel_size=2, stride=2)
return x
class ResnetBlock(nn.Module):
def __init__(self, *, in_channels, out_channels=None, conv_shortcut=False,
dropout, temb_channels=512):
super().__init__()
self.in_channels = in_channels
out_channels = in_channels if out_channels is None else out_channels
self.out_channels = out_channels
self.use_conv_shortcut = conv_shortcut
self.swish = torch.nn.SiLU(inplace=True)
self.norm1 = Normalize(in_channels)
self.conv1 = ops.Conv2d(in_channels,
out_channels,
kernel_size=3,
stride=1,
padding=1)
if temb_channels > 0:
self.temb_proj = ops.Linear(temb_channels,
out_channels)
self.norm2 = Normalize(out_channels)
self.dropout = torch.nn.Dropout(dropout, inplace=True)
self.conv2 = ops.Conv2d(out_channels,
out_channels,
kernel_size=3,
stride=1,
padding=1)
if self.in_channels != self.out_channels:
if self.use_conv_shortcut:
self.conv_shortcut = ops.Conv2d(in_channels,
out_channels,
kernel_size=3,
stride=1,
padding=1)
else:
self.nin_shortcut = ops.Conv2d(in_channels,
out_channels,
kernel_size=1,
stride=1,
padding=0)
def forward(self, x, temb):
h = x
h = self.norm1(h)
h = self.swish(h)
h = self.conv1(h)
if temb is not None:
h = h + self.temb_proj(self.swish(temb))[:,:,None,None]
h = self.norm2(h)
h = self.swish(h)
h = self.dropout(h)
h = self.conv2(h)
if self.in_channels != self.out_channels:
if self.use_conv_shortcut:
x = self.conv_shortcut(x)
else:
x = self.nin_shortcut(x)
return x+h
def slice_attention(q, k, v):
r1 = torch.zeros_like(k, device=q.device)
scale = (int(q.shape[-1])**(-0.5))
mem_free_total = model_management.get_free_memory(q.device)
gb = 1024 ** 3
tensor_size = q.shape[0] * q.shape[1] * k.shape[2] * q.element_size()
modifier = 3 if q.element_size() == 2 else 2.5
mem_required = tensor_size * modifier
steps = 1
if mem_required > mem_free_total:
steps = 2**(math.ceil(math.log(mem_required / mem_free_total, 2)))
while True:
try:
slice_size = q.shape[1] // steps if (q.shape[1] % steps) == 0 else q.shape[1]
for i in range(0, q.shape[1], slice_size):
end = i + slice_size
s1 = torch.bmm(q[:, i:end], k) * scale
s2 = torch.nn.functional.softmax(s1, dim=2).permute(0,2,1)
del s1
r1[:, :, i:end] = torch.bmm(v, s2)
del s2
break
except model_management.OOM_EXCEPTION as e:
model_management.soft_empty_cache(True)
steps *= 2
if steps > 128:
raise e
print("out of memory error, increasing steps and trying again", steps)
return r1
def normal_attention(q, k, v):
# compute attention
b,c,h,w = q.shape
q = q.reshape(b,c,h*w)
q = q.permute(0,2,1) # b,hw,c
k = k.reshape(b,c,h*w) # b,c,hw
v = v.reshape(b,c,h*w)
r1 = slice_attention(q, k, v)
h_ = r1.reshape(b,c,h,w)
del r1
return h_
def xformers_attention(q, k, v):
# compute attention
B, C, H, W = q.shape
q, k, v = map(
lambda t: t.view(B, C, -1).transpose(1, 2).contiguous(),
(q, k, v),
)
try:
out = xformers.ops.memory_efficient_attention(q, k, v, attn_bias=None)
out = out.transpose(1, 2).reshape(B, C, H, W)
except NotImplementedError as e:
out = slice_attention(q.view(B, -1, C), k.view(B, -1, C).transpose(1, 2), v.view(B, -1, C).transpose(1, 2)).reshape(B, C, H, W)
return out
def pytorch_attention(q, k, v):
# compute attention
B, C, H, W = q.shape
q, k, v = map(
lambda t: t.view(B, 1, C, -1).transpose(2, 3).contiguous(),
(q, k, v),
)
try:
out = torch.nn.functional.scaled_dot_product_attention(q, k, v, attn_mask=None, dropout_p=0.0, is_causal=False)
out = out.transpose(2, 3).reshape(B, C, H, W)
except model_management.OOM_EXCEPTION as e:
print("scaled_dot_product_attention OOMed: switched to slice attention")
out = slice_attention(q.view(B, -1, C), k.view(B, -1, C).transpose(1, 2), v.view(B, -1, C).transpose(1, 2)).reshape(B, C, H, W)
return out
class AttnBlock(nn.Module):
def __init__(self, in_channels):
super().__init__()
self.in_channels = in_channels
self.norm = Normalize(in_channels)
self.q = ops.Conv2d(in_channels,
in_channels,
kernel_size=1,
stride=1,
padding=0)
self.k = ops.Conv2d(in_channels,
in_channels,
kernel_size=1,
stride=1,
padding=0)
self.v = ops.Conv2d(in_channels,
in_channels,
kernel_size=1,
stride=1,
padding=0)
self.proj_out = ops.Conv2d(in_channels,
in_channels,
kernel_size=1,
stride=1,
padding=0)
if model_management.xformers_enabled_vae():
print("Using xformers attention in VAE")
self.optimized_attention = xformers_attention
elif model_management.pytorch_attention_enabled():
print("Using pytorch attention in VAE")
self.optimized_attention = pytorch_attention
else:
print("Using split attention in VAE")
self.optimized_attention = normal_attention
def forward(self, x):
h_ = x
h_ = self.norm(h_)
q = self.q(h_)
k = self.k(h_)
v = self.v(h_)
h_ = self.optimized_attention(q, k, v)
h_ = self.proj_out(h_)
return x+h_
def make_attn(in_channels, attn_type="vanilla", attn_kwargs=None):
return AttnBlock(in_channels)
class Model(nn.Module):
def __init__(self, *, ch, out_ch, ch_mult=(1,2,4,8), num_res_blocks,
attn_resolutions, dropout=0.0, resamp_with_conv=True, in_channels,
resolution, use_timestep=True, use_linear_attn=False, attn_type="vanilla"):
super().__init__()
if use_linear_attn: attn_type = "linear"
self.ch = ch
self.temb_ch = self.ch*4
self.num_resolutions = len(ch_mult)
self.num_res_blocks = num_res_blocks
self.resolution = resolution
self.in_channels = in_channels
self.use_timestep = use_timestep
if self.use_timestep:
# timestep embedding
self.temb = nn.Module()
self.temb.dense = nn.ModuleList([
ops.Linear(self.ch,
self.temb_ch),
ops.Linear(self.temb_ch,
self.temb_ch),
])
# downsampling
self.conv_in = ops.Conv2d(in_channels,
self.ch,
kernel_size=3,
stride=1,
padding=1)
curr_res = resolution
in_ch_mult = (1,)+tuple(ch_mult)
self.down = nn.ModuleList()
for i_level in range(self.num_resolutions):
block = nn.ModuleList()
attn = nn.ModuleList()
block_in = ch*in_ch_mult[i_level]
block_out = ch*ch_mult[i_level]
for i_block in range(self.num_res_blocks):
block.append(ResnetBlock(in_channels=block_in,
out_channels=block_out,
temb_channels=self.temb_ch,
dropout=dropout))
block_in = block_out
if curr_res in attn_resolutions:
attn.append(make_attn(block_in, attn_type=attn_type))
down = nn.Module()
down.block = block
down.attn = attn
if i_level != self.num_resolutions-1:
down.downsample = Downsample(block_in, resamp_with_conv)
curr_res = curr_res // 2
self.down.append(down)
# middle
self.mid = nn.Module()
self.mid.block_1 = ResnetBlock(in_channels=block_in,
out_channels=block_in,
temb_channels=self.temb_ch,
dropout=dropout)
self.mid.attn_1 = make_attn(block_in, attn_type=attn_type)
self.mid.block_2 = ResnetBlock(in_channels=block_in,
out_channels=block_in,
temb_channels=self.temb_ch,
dropout=dropout)
# upsampling
self.up = nn.ModuleList()
for i_level in reversed(range(self.num_resolutions)):
block = nn.ModuleList()
attn = nn.ModuleList()
block_out = ch*ch_mult[i_level]
skip_in = ch*ch_mult[i_level]
for i_block in range(self.num_res_blocks+1):
if i_block == self.num_res_blocks:
skip_in = ch*in_ch_mult[i_level]
block.append(ResnetBlock(in_channels=block_in+skip_in,
out_channels=block_out,
temb_channels=self.temb_ch,
dropout=dropout))
block_in = block_out
if curr_res in attn_resolutions:
attn.append(make_attn(block_in, attn_type=attn_type))
up = nn.Module()
up.block = block
up.attn = attn
if i_level != 0:
up.upsample = Upsample(block_in, resamp_with_conv)
curr_res = curr_res * 2
self.up.insert(0, up) # prepend to get consistent order
# end
self.norm_out = Normalize(block_in)
self.conv_out = ops.Conv2d(block_in,
out_ch,
kernel_size=3,
stride=1,
padding=1)
def forward(self, x, t=None, context=None):
#assert x.shape[2] == x.shape[3] == self.resolution
if context is not None:
# assume aligned context, cat along channel axis
x = torch.cat((x, context), dim=1)
if self.use_timestep:
# timestep embedding
assert t is not None
temb = get_timestep_embedding(t, self.ch)
temb = self.temb.dense[0](temb)
temb = nonlinearity(temb)
temb = self.temb.dense[1](temb)
else:
temb = None
# downsampling
hs = [self.conv_in(x)]
for i_level in range(self.num_resolutions):
for i_block in range(self.num_res_blocks):
h = self.down[i_level].block[i_block](hs[-1], temb)
if len(self.down[i_level].attn) > 0:
h = self.down[i_level].attn[i_block](h)
hs.append(h)
if i_level != self.num_resolutions-1:
hs.append(self.down[i_level].downsample(hs[-1]))
# middle
h = hs[-1]
h = self.mid.block_1(h, temb)
h = self.mid.attn_1(h)
h = self.mid.block_2(h, temb)
# upsampling
for i_level in reversed(range(self.num_resolutions)):
for i_block in range(self.num_res_blocks+1):
h = self.up[i_level].block[i_block](
torch.cat([h, hs.pop()], dim=1), temb)
if len(self.up[i_level].attn) > 0:
h = self.up[i_level].attn[i_block](h)
if i_level != 0:
h = self.up[i_level].upsample(h)
# end
h = self.norm_out(h)
h = nonlinearity(h)
h = self.conv_out(h)
return h
def get_last_layer(self):
return self.conv_out.weight
class Encoder(nn.Module):
def __init__(self, *, ch, out_ch, ch_mult=(1,2,4,8), num_res_blocks,
attn_resolutions, dropout=0.0, resamp_with_conv=True, in_channels,
resolution, z_channels, double_z=True, use_linear_attn=False, attn_type="vanilla",
**ignore_kwargs):
super().__init__()
if use_linear_attn: attn_type = "linear"
self.ch = ch
self.temb_ch = 0
self.num_resolutions = len(ch_mult)
self.num_res_blocks = num_res_blocks
self.resolution = resolution
self.in_channels = in_channels
# downsampling
self.conv_in = ops.Conv2d(in_channels,
self.ch,
kernel_size=3,
stride=1,
padding=1)
curr_res = resolution
in_ch_mult = (1,)+tuple(ch_mult)
self.in_ch_mult = in_ch_mult
self.down = nn.ModuleList()
for i_level in range(self.num_resolutions):
block = nn.ModuleList()
attn = nn.ModuleList()
block_in = ch*in_ch_mult[i_level]
block_out = ch*ch_mult[i_level]
for i_block in range(self.num_res_blocks):
block.append(ResnetBlock(in_channels=block_in,
out_channels=block_out,
temb_channels=self.temb_ch,
dropout=dropout))
block_in = block_out
if curr_res in attn_resolutions:
attn.append(make_attn(block_in, attn_type=attn_type))
down = nn.Module()
down.block = block
down.attn = attn
if i_level != self.num_resolutions-1:
down.downsample = Downsample(block_in, resamp_with_conv)
curr_res = curr_res // 2
self.down.append(down)
# middle
self.mid = nn.Module()
self.mid.block_1 = ResnetBlock(in_channels=block_in,
out_channels=block_in,
temb_channels=self.temb_ch,
dropout=dropout)
self.mid.attn_1 = make_attn(block_in, attn_type=attn_type)
self.mid.block_2 = ResnetBlock(in_channels=block_in,
out_channels=block_in,
temb_channels=self.temb_ch,
dropout=dropout)
# end
self.norm_out = Normalize(block_in)
self.conv_out = ops.Conv2d(block_in,
2*z_channels if double_z else z_channels,
kernel_size=3,
stride=1,
padding=1)
def forward(self, x):
# timestep embedding
temb = None
# downsampling
h = self.conv_in(x)
for i_level in range(self.num_resolutions):
for i_block in range(self.num_res_blocks):
h = self.down[i_level].block[i_block](h, temb)
if len(self.down[i_level].attn) > 0:
h = self.down[i_level].attn[i_block](h)
if i_level != self.num_resolutions-1:
h = self.down[i_level].downsample(h)
# middle
h = self.mid.block_1(h, temb)
h = self.mid.attn_1(h)
h = self.mid.block_2(h, temb)
# end
h = self.norm_out(h)
h = nonlinearity(h)
h = self.conv_out(h)
return h
class Decoder(nn.Module):
def __init__(self, *, ch, out_ch, ch_mult=(1,2,4,8), num_res_blocks,
attn_resolutions, dropout=0.0, resamp_with_conv=True, in_channels,
resolution, z_channels, give_pre_end=False, tanh_out=False, use_linear_attn=False,
conv_out_op=ops.Conv2d,
resnet_op=ResnetBlock,
attn_op=AttnBlock,
**ignorekwargs):
super().__init__()
if use_linear_attn: attn_type = "linear"
self.ch = ch
self.temb_ch = 0
self.num_resolutions = len(ch_mult)
self.num_res_blocks = num_res_blocks
self.resolution = resolution
self.in_channels = in_channels
self.give_pre_end = give_pre_end
self.tanh_out = tanh_out
# compute in_ch_mult, block_in and curr_res at lowest res
in_ch_mult = (1,)+tuple(ch_mult)
block_in = ch*ch_mult[self.num_resolutions-1]
curr_res = resolution // 2**(self.num_resolutions-1)
self.z_shape = (1,z_channels,curr_res,curr_res)
print("Working with z of shape {} = {} dimensions.".format(
self.z_shape, np.prod(self.z_shape)))
# z to block_in
self.conv_in = ops.Conv2d(z_channels,
block_in,
kernel_size=3,
stride=1,
padding=1)
# middle
self.mid = nn.Module()
self.mid.block_1 = resnet_op(in_channels=block_in,
out_channels=block_in,
temb_channels=self.temb_ch,
dropout=dropout)
self.mid.attn_1 = attn_op(block_in)
self.mid.block_2 = resnet_op(in_channels=block_in,
out_channels=block_in,
temb_channels=self.temb_ch,
dropout=dropout)
# upsampling
self.up = nn.ModuleList()
for i_level in reversed(range(self.num_resolutions)):
block = nn.ModuleList()
attn = nn.ModuleList()
block_out = ch*ch_mult[i_level]
for i_block in range(self.num_res_blocks+1):
block.append(resnet_op(in_channels=block_in,
out_channels=block_out,
temb_channels=self.temb_ch,
dropout=dropout))
block_in = block_out
if curr_res in attn_resolutions:
attn.append(attn_op(block_in))
up = nn.Module()
up.block = block
up.attn = attn
if i_level != 0:
up.upsample = Upsample(block_in, resamp_with_conv)
curr_res = curr_res * 2
self.up.insert(0, up) # prepend to get consistent order
# end
self.norm_out = Normalize(block_in)
self.conv_out = conv_out_op(block_in,
out_ch,
kernel_size=3,
stride=1,
padding=1)
def forward(self, z, **kwargs):
#assert z.shape[1:] == self.z_shape[1:]
self.last_z_shape = z.shape
# timestep embedding
temb = None
# z to block_in
h = self.conv_in(z)
# middle
h = self.mid.block_1(h, temb, **kwargs)
h = self.mid.attn_1(h, **kwargs)
h = self.mid.block_2(h, temb, **kwargs)
# upsampling
for i_level in reversed(range(self.num_resolutions)):
for i_block in range(self.num_res_blocks+1):
h = self.up[i_level].block[i_block](h, temb, **kwargs)
if len(self.up[i_level].attn) > 0:
h = self.up[i_level].attn[i_block](h, **kwargs)
if i_level != 0:
h = self.up[i_level].upsample(h)
# end
if self.give_pre_end:
return h
h = self.norm_out(h)
h = nonlinearity(h)
h = self.conv_out(h, **kwargs)
if self.tanh_out:
h = torch.tanh(h)
return h

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from abc import abstractmethod
import math
import numpy as np
import torch as th
import torch.nn as nn
import torch.nn.functional as F
from einops import rearrange
from functools import partial
from .util import (
checkpoint,
avg_pool_nd,
zero_module,
timestep_embedding,
AlphaBlender,
)
from ..attention import SpatialTransformer, SpatialVideoTransformer, default
from ldm_patched.ldm.util import exists
import ldm_patched.modules.ops
ops = ldm_patched.modules.ops.disable_weight_init
class TimestepBlock(nn.Module):
"""
Any module where forward() takes timestep embeddings as a second argument.
"""
@abstractmethod
def forward(self, x, emb):
"""
Apply the module to `x` given `emb` timestep embeddings.
"""
#This is needed because accelerate makes a copy of transformer_options which breaks "transformer_index"
def forward_timestep_embed(ts, x, emb, context=None, transformer_options={}, output_shape=None, time_context=None, num_video_frames=None, image_only_indicator=None):
for layer in ts:
if isinstance(layer, VideoResBlock):
x = layer(x, emb, num_video_frames, image_only_indicator)
elif isinstance(layer, TimestepBlock):
x = layer(x, emb)
elif isinstance(layer, SpatialVideoTransformer):
x = layer(x, context, time_context, num_video_frames, image_only_indicator, transformer_options)
if "transformer_index" in transformer_options:
transformer_options["transformer_index"] += 1
elif isinstance(layer, SpatialTransformer):
x = layer(x, context, transformer_options)
if "transformer_index" in transformer_options:
transformer_options["transformer_index"] += 1
elif isinstance(layer, Upsample):
x = layer(x, output_shape=output_shape)
else:
x = layer(x)
return x
class TimestepEmbedSequential(nn.Sequential, TimestepBlock):
"""
A sequential module that passes timestep embeddings to the children that
support it as an extra input.
"""
def forward(self, *args, **kwargs):
return forward_timestep_embed(self, *args, **kwargs)
class Upsample(nn.Module):
"""
An upsampling layer with an optional convolution.
:param channels: channels in the inputs and outputs.
:param use_conv: a bool determining if a convolution is applied.
:param dims: determines if the signal is 1D, 2D, or 3D. If 3D, then
upsampling occurs in the inner-two dimensions.
"""
def __init__(self, channels, use_conv, dims=2, out_channels=None, padding=1, dtype=None, device=None, operations=ops):
super().__init__()
self.channels = channels
self.out_channels = out_channels or channels
self.use_conv = use_conv
self.dims = dims
if use_conv:
self.conv = operations.conv_nd(dims, self.channels, self.out_channels, 3, padding=padding, dtype=dtype, device=device)
def forward(self, x, output_shape=None):
assert x.shape[1] == self.channels
if self.dims == 3:
shape = [x.shape[2], x.shape[3] * 2, x.shape[4] * 2]
if output_shape is not None:
shape[1] = output_shape[3]
shape[2] = output_shape[4]
else:
shape = [x.shape[2] * 2, x.shape[3] * 2]
if output_shape is not None:
shape[0] = output_shape[2]
shape[1] = output_shape[3]
x = F.interpolate(x, size=shape, mode="nearest")
if self.use_conv:
x = self.conv(x)
return x
class Downsample(nn.Module):
"""
A downsampling layer with an optional convolution.
:param channels: channels in the inputs and outputs.
:param use_conv: a bool determining if a convolution is applied.
:param dims: determines if the signal is 1D, 2D, or 3D. If 3D, then
downsampling occurs in the inner-two dimensions.
"""
def __init__(self, channels, use_conv, dims=2, out_channels=None, padding=1, dtype=None, device=None, operations=ops):
super().__init__()
self.channels = channels
self.out_channels = out_channels or channels
self.use_conv = use_conv
self.dims = dims
stride = 2 if dims != 3 else (1, 2, 2)
if use_conv:
self.op = operations.conv_nd(
dims, self.channels, self.out_channels, 3, stride=stride, padding=padding, dtype=dtype, device=device
)
else:
assert self.channels == self.out_channels
self.op = avg_pool_nd(dims, kernel_size=stride, stride=stride)
def forward(self, x):
assert x.shape[1] == self.channels
return self.op(x)
class ResBlock(TimestepBlock):
"""
A residual block that can optionally change the number of channels.
:param channels: the number of input channels.
:param emb_channels: the number of timestep embedding channels.
:param dropout: the rate of dropout.
:param out_channels: if specified, the number of out channels.
:param use_conv: if True and out_channels is specified, use a spatial
convolution instead of a smaller 1x1 convolution to change the
channels in the skip connection.
:param dims: determines if the signal is 1D, 2D, or 3D.
:param use_checkpoint: if True, use gradient checkpointing on this module.
:param up: if True, use this block for upsampling.
:param down: if True, use this block for downsampling.
"""
def __init__(
self,
channels,
emb_channels,
dropout,
out_channels=None,
use_conv=False,
use_scale_shift_norm=False,
dims=2,
use_checkpoint=False,
up=False,
down=False,
kernel_size=3,
exchange_temb_dims=False,
skip_t_emb=False,
dtype=None,
device=None,
operations=ops
):
super().__init__()
self.channels = channels
self.emb_channels = emb_channels
self.dropout = dropout
self.out_channels = out_channels or channels
self.use_conv = use_conv
self.use_checkpoint = use_checkpoint
self.use_scale_shift_norm = use_scale_shift_norm
self.exchange_temb_dims = exchange_temb_dims
if isinstance(kernel_size, list):
padding = [k // 2 for k in kernel_size]
else:
padding = kernel_size // 2
self.in_layers = nn.Sequential(
operations.GroupNorm(32, channels, dtype=dtype, device=device),
nn.SiLU(),
operations.conv_nd(dims, channels, self.out_channels, kernel_size, padding=padding, dtype=dtype, device=device),
)
self.updown = up or down
if up:
self.h_upd = Upsample(channels, False, dims, dtype=dtype, device=device)
self.x_upd = Upsample(channels, False, dims, dtype=dtype, device=device)
elif down:
self.h_upd = Downsample(channels, False, dims, dtype=dtype, device=device)
self.x_upd = Downsample(channels, False, dims, dtype=dtype, device=device)
else:
self.h_upd = self.x_upd = nn.Identity()
self.skip_t_emb = skip_t_emb
if self.skip_t_emb:
self.emb_layers = None
self.exchange_temb_dims = False
else:
self.emb_layers = nn.Sequential(
nn.SiLU(),
operations.Linear(
emb_channels,
2 * self.out_channels if use_scale_shift_norm else self.out_channels, dtype=dtype, device=device
),
)
self.out_layers = nn.Sequential(
operations.GroupNorm(32, self.out_channels, dtype=dtype, device=device),
nn.SiLU(),
nn.Dropout(p=dropout),
operations.conv_nd(dims, self.out_channels, self.out_channels, kernel_size, padding=padding, dtype=dtype, device=device)
,
)
if self.out_channels == channels:
self.skip_connection = nn.Identity()
elif use_conv:
self.skip_connection = operations.conv_nd(
dims, channels, self.out_channels, kernel_size, padding=padding, dtype=dtype, device=device
)
else:
self.skip_connection = operations.conv_nd(dims, channels, self.out_channels, 1, dtype=dtype, device=device)
def forward(self, x, emb):
"""
Apply the block to a Tensor, conditioned on a timestep embedding.
:param x: an [N x C x ...] Tensor of features.
:param emb: an [N x emb_channels] Tensor of timestep embeddings.
:return: an [N x C x ...] Tensor of outputs.
"""
return checkpoint(
self._forward, (x, emb), self.parameters(), self.use_checkpoint
)
def _forward(self, x, emb):
if self.updown:
in_rest, in_conv = self.in_layers[:-1], self.in_layers[-1]
h = in_rest(x)
h = self.h_upd(h)
x = self.x_upd(x)
h = in_conv(h)
else:
h = self.in_layers(x)
emb_out = None
if not self.skip_t_emb:
emb_out = self.emb_layers(emb).type(h.dtype)
while len(emb_out.shape) < len(h.shape):
emb_out = emb_out[..., None]
if self.use_scale_shift_norm:
out_norm, out_rest = self.out_layers[0], self.out_layers[1:]
h = out_norm(h)
if emb_out is not None:
scale, shift = th.chunk(emb_out, 2, dim=1)
h *= (1 + scale)
h += shift
h = out_rest(h)
else:
if emb_out is not None:
if self.exchange_temb_dims:
emb_out = rearrange(emb_out, "b t c ... -> b c t ...")
h = h + emb_out
h = self.out_layers(h)
return self.skip_connection(x) + h
class VideoResBlock(ResBlock):
def __init__(
self,
channels: int,
emb_channels: int,
dropout: float,
video_kernel_size=3,
merge_strategy: str = "fixed",
merge_factor: float = 0.5,
out_channels=None,
use_conv: bool = False,
use_scale_shift_norm: bool = False,
dims: int = 2,
use_checkpoint: bool = False,
up: bool = False,
down: bool = False,
dtype=None,
device=None,
operations=ops
):
super().__init__(
channels,
emb_channels,
dropout,
out_channels=out_channels,
use_conv=use_conv,
use_scale_shift_norm=use_scale_shift_norm,
dims=dims,
use_checkpoint=use_checkpoint,
up=up,
down=down,
dtype=dtype,
device=device,
operations=operations
)
self.time_stack = ResBlock(
default(out_channels, channels),
emb_channels,
dropout=dropout,
dims=3,
out_channels=default(out_channels, channels),
use_scale_shift_norm=False,
use_conv=False,
up=False,
down=False,
kernel_size=video_kernel_size,
use_checkpoint=use_checkpoint,
exchange_temb_dims=True,
dtype=dtype,
device=device,
operations=operations
)
self.time_mixer = AlphaBlender(
alpha=merge_factor,
merge_strategy=merge_strategy,
rearrange_pattern="b t -> b 1 t 1 1",
)
def forward(
self,
x: th.Tensor,
emb: th.Tensor,
num_video_frames: int,
image_only_indicator = None,
) -> th.Tensor:
x = super().forward(x, emb)
x_mix = rearrange(x, "(b t) c h w -> b c t h w", t=num_video_frames)
x = rearrange(x, "(b t) c h w -> b c t h w", t=num_video_frames)
x = self.time_stack(
x, rearrange(emb, "(b t) ... -> b t ...", t=num_video_frames)
)
x = self.time_mixer(
x_spatial=x_mix, x_temporal=x, image_only_indicator=image_only_indicator
)
x = rearrange(x, "b c t h w -> (b t) c h w")
return x
class Timestep(nn.Module):
def __init__(self, dim):
super().__init__()
self.dim = dim
def forward(self, t):
return timestep_embedding(t, self.dim)
def apply_control(h, control, name):
if control is not None and name in control and len(control[name]) > 0:
ctrl = control[name].pop()
if ctrl is not None:
try:
h += ctrl
except:
print("warning control could not be applied", h.shape, ctrl.shape)
return h
class UNetModel(nn.Module):
"""
The full UNet model with attention and timestep embedding.
:param in_channels: channels in the input Tensor.
:param model_channels: base channel count for the model.
:param out_channels: channels in the output Tensor.
:param num_res_blocks: number of residual blocks per downsample.
:param dropout: the dropout probability.
:param channel_mult: channel multiplier for each level of the UNet.
:param conv_resample: if True, use learned convolutions for upsampling and
downsampling.
:param dims: determines if the signal is 1D, 2D, or 3D.
:param num_classes: if specified (as an int), then this model will be
class-conditional with `num_classes` classes.
:param use_checkpoint: use gradient checkpointing to reduce memory usage.
:param num_heads: the number of attention heads in each attention layer.
:param num_heads_channels: if specified, ignore num_heads and instead use
a fixed channel width per attention head.
:param num_heads_upsample: works with num_heads to set a different number
of heads for upsampling. Deprecated.
:param use_scale_shift_norm: use a FiLM-like conditioning mechanism.
:param resblock_updown: use residual blocks for up/downsampling.
:param use_new_attention_order: use a different attention pattern for potentially
increased efficiency.
"""
def __init__(
self,
image_size,
in_channels,
model_channels,
out_channels,
num_res_blocks,
dropout=0,
channel_mult=(1, 2, 4, 8),
conv_resample=True,
dims=2,
num_classes=None,
use_checkpoint=False,
dtype=th.float32,
num_heads=-1,
num_head_channels=-1,
num_heads_upsample=-1,
use_scale_shift_norm=False,
resblock_updown=False,
use_new_attention_order=False,
use_spatial_transformer=False, # custom transformer support
transformer_depth=1, # custom transformer support
context_dim=None, # custom transformer support
n_embed=None, # custom support for prediction of discrete ids into codebook of first stage vq model
legacy=True,
disable_self_attentions=None,
num_attention_blocks=None,
disable_middle_self_attn=False,
use_linear_in_transformer=False,
adm_in_channels=None,
transformer_depth_middle=None,
transformer_depth_output=None,
use_temporal_resblock=False,
use_temporal_attention=False,
time_context_dim=None,
extra_ff_mix_layer=False,
use_spatial_context=False,
merge_strategy=None,
merge_factor=0.0,
video_kernel_size=None,
disable_temporal_crossattention=False,
max_ddpm_temb_period=10000,
device=None,
operations=ops,
):
super().__init__()
if context_dim is not None:
assert use_spatial_transformer, 'Fool!! You forgot to use the spatial transformer for your cross-attention conditioning...'
# from omegaconf.listconfig import ListConfig
# if type(context_dim) == ListConfig:
# context_dim = list(context_dim)
if num_heads_upsample == -1:
num_heads_upsample = num_heads
if num_heads == -1:
assert num_head_channels != -1, 'Either num_heads or num_head_channels has to be set'
if num_head_channels == -1:
assert num_heads != -1, 'Either num_heads or num_head_channels has to be set'
self.in_channels = in_channels
self.model_channels = model_channels
self.out_channels = out_channels
if isinstance(num_res_blocks, int):
self.num_res_blocks = len(channel_mult) * [num_res_blocks]
else:
if len(num_res_blocks) != len(channel_mult):
raise ValueError("provide num_res_blocks either as an int (globally constant) or "
"as a list/tuple (per-level) with the same length as channel_mult")
self.num_res_blocks = num_res_blocks
if disable_self_attentions is not None:
# should be a list of booleans, indicating whether to disable self-attention in TransformerBlocks or not
assert len(disable_self_attentions) == len(channel_mult)
if num_attention_blocks is not None:
assert len(num_attention_blocks) == len(self.num_res_blocks)
transformer_depth = transformer_depth[:]
transformer_depth_output = transformer_depth_output[:]
self.dropout = dropout
self.channel_mult = channel_mult
self.conv_resample = conv_resample
self.num_classes = num_classes
self.use_checkpoint = use_checkpoint
self.dtype = dtype
self.num_heads = num_heads
self.num_head_channels = num_head_channels
self.num_heads_upsample = num_heads_upsample
self.use_temporal_resblocks = use_temporal_resblock
self.predict_codebook_ids = n_embed is not None
self.default_num_video_frames = None
self.default_image_only_indicator = None
time_embed_dim = model_channels * 4
self.time_embed = nn.Sequential(
operations.Linear(model_channels, time_embed_dim, dtype=self.dtype, device=device),
nn.SiLU(),
operations.Linear(time_embed_dim, time_embed_dim, dtype=self.dtype, device=device),
)
if self.num_classes is not None:
if isinstance(self.num_classes, int):
self.label_emb = nn.Embedding(num_classes, time_embed_dim, dtype=self.dtype, device=device)
elif self.num_classes == "continuous":
print("setting up linear c_adm embedding layer")
self.label_emb = nn.Linear(1, time_embed_dim)
elif self.num_classes == "sequential":
assert adm_in_channels is not None
self.label_emb = nn.Sequential(
nn.Sequential(
operations.Linear(adm_in_channels, time_embed_dim, dtype=self.dtype, device=device),
nn.SiLU(),
operations.Linear(time_embed_dim, time_embed_dim, dtype=self.dtype, device=device),
)
)
else:
raise ValueError()
self.input_blocks = nn.ModuleList(
[
TimestepEmbedSequential(
operations.conv_nd(dims, in_channels, model_channels, 3, padding=1, dtype=self.dtype, device=device)
)
]
)
self._feature_size = model_channels
input_block_chans = [model_channels]
ch = model_channels
ds = 1
def get_attention_layer(
ch,
num_heads,
dim_head,
depth=1,
context_dim=None,
use_checkpoint=False,
disable_self_attn=False,
):
if use_temporal_attention:
return SpatialVideoTransformer(
ch,
num_heads,
dim_head,
depth=depth,
context_dim=context_dim,
time_context_dim=time_context_dim,
dropout=dropout,
ff_in=extra_ff_mix_layer,
use_spatial_context=use_spatial_context,
merge_strategy=merge_strategy,
merge_factor=merge_factor,
checkpoint=use_checkpoint,
use_linear=use_linear_in_transformer,
disable_self_attn=disable_self_attn,
disable_temporal_crossattention=disable_temporal_crossattention,
max_time_embed_period=max_ddpm_temb_period,
dtype=self.dtype, device=device, operations=operations
)
else:
return SpatialTransformer(
ch, num_heads, dim_head, depth=depth, context_dim=context_dim,
disable_self_attn=disable_self_attn, use_linear=use_linear_in_transformer,
use_checkpoint=use_checkpoint, dtype=self.dtype, device=device, operations=operations
)
def get_resblock(
merge_factor,
merge_strategy,
video_kernel_size,
ch,
time_embed_dim,
dropout,
out_channels,
dims,
use_checkpoint,
use_scale_shift_norm,
down=False,
up=False,
dtype=None,
device=None,
operations=ops
):
if self.use_temporal_resblocks:
return VideoResBlock(
merge_factor=merge_factor,
merge_strategy=merge_strategy,
video_kernel_size=video_kernel_size,
channels=ch,
emb_channels=time_embed_dim,
dropout=dropout,
out_channels=out_channels,
dims=dims,
use_checkpoint=use_checkpoint,
use_scale_shift_norm=use_scale_shift_norm,
down=down,
up=up,
dtype=dtype,
device=device,
operations=operations
)
else:
return ResBlock(
channels=ch,
emb_channels=time_embed_dim,
dropout=dropout,
out_channels=out_channels,
use_checkpoint=use_checkpoint,
dims=dims,
use_scale_shift_norm=use_scale_shift_norm,
down=down,
up=up,
dtype=dtype,
device=device,
operations=operations
)
for level, mult in enumerate(channel_mult):
for nr in range(self.num_res_blocks[level]):
layers = [
get_resblock(
merge_factor=merge_factor,
merge_strategy=merge_strategy,
video_kernel_size=video_kernel_size,
ch=ch,
time_embed_dim=time_embed_dim,
dropout=dropout,
out_channels=mult * model_channels,
dims=dims,
use_checkpoint=use_checkpoint,
use_scale_shift_norm=use_scale_shift_norm,
dtype=self.dtype,
device=device,
operations=operations,
)
]
ch = mult * model_channels
num_transformers = transformer_depth.pop(0)
if num_transformers > 0:
if num_head_channels == -1:
dim_head = ch // num_heads
else:
num_heads = ch // num_head_channels
dim_head = num_head_channels
if legacy:
#num_heads = 1
dim_head = ch // num_heads if use_spatial_transformer else num_head_channels
if exists(disable_self_attentions):
disabled_sa = disable_self_attentions[level]
else:
disabled_sa = False
if not exists(num_attention_blocks) or nr < num_attention_blocks[level]:
layers.append(get_attention_layer(
ch, num_heads, dim_head, depth=num_transformers, context_dim=context_dim,
disable_self_attn=disabled_sa, use_checkpoint=use_checkpoint)
)
self.input_blocks.append(TimestepEmbedSequential(*layers))
self._feature_size += ch
input_block_chans.append(ch)
if level != len(channel_mult) - 1:
out_ch = ch
self.input_blocks.append(
TimestepEmbedSequential(
get_resblock(
merge_factor=merge_factor,
merge_strategy=merge_strategy,
video_kernel_size=video_kernel_size,
ch=ch,
time_embed_dim=time_embed_dim,
dropout=dropout,
out_channels=out_ch,
dims=dims,
use_checkpoint=use_checkpoint,
use_scale_shift_norm=use_scale_shift_norm,
down=True,
dtype=self.dtype,
device=device,
operations=operations
)
if resblock_updown
else Downsample(
ch, conv_resample, dims=dims, out_channels=out_ch, dtype=self.dtype, device=device, operations=operations
)
)
)
ch = out_ch
input_block_chans.append(ch)
ds *= 2
self._feature_size += ch
if num_head_channels == -1:
dim_head = ch // num_heads
else:
num_heads = ch // num_head_channels
dim_head = num_head_channels
if legacy:
#num_heads = 1
dim_head = ch // num_heads if use_spatial_transformer else num_head_channels
mid_block = [
get_resblock(
merge_factor=merge_factor,
merge_strategy=merge_strategy,
video_kernel_size=video_kernel_size,
ch=ch,
time_embed_dim=time_embed_dim,
dropout=dropout,
out_channels=None,
dims=dims,
use_checkpoint=use_checkpoint,
use_scale_shift_norm=use_scale_shift_norm,
dtype=self.dtype,
device=device,
operations=operations
)]
if transformer_depth_middle >= 0:
mid_block += [get_attention_layer( # always uses a self-attn
ch, num_heads, dim_head, depth=transformer_depth_middle, context_dim=context_dim,
disable_self_attn=disable_middle_self_attn, use_checkpoint=use_checkpoint
),
get_resblock(
merge_factor=merge_factor,
merge_strategy=merge_strategy,
video_kernel_size=video_kernel_size,
ch=ch,
time_embed_dim=time_embed_dim,
dropout=dropout,
out_channels=None,
dims=dims,
use_checkpoint=use_checkpoint,
use_scale_shift_norm=use_scale_shift_norm,
dtype=self.dtype,
device=device,
operations=operations
)]
self.middle_block = TimestepEmbedSequential(*mid_block)
self._feature_size += ch
self.output_blocks = nn.ModuleList([])
for level, mult in list(enumerate(channel_mult))[::-1]:
for i in range(self.num_res_blocks[level] + 1):
ich = input_block_chans.pop()
layers = [
get_resblock(
merge_factor=merge_factor,
merge_strategy=merge_strategy,
video_kernel_size=video_kernel_size,
ch=ch + ich,
time_embed_dim=time_embed_dim,
dropout=dropout,
out_channels=model_channels * mult,
dims=dims,
use_checkpoint=use_checkpoint,
use_scale_shift_norm=use_scale_shift_norm,
dtype=self.dtype,
device=device,
operations=operations
)
]
ch = model_channels * mult
num_transformers = transformer_depth_output.pop()
if num_transformers > 0:
if num_head_channels == -1:
dim_head = ch // num_heads
else:
num_heads = ch // num_head_channels
dim_head = num_head_channels
if legacy:
#num_heads = 1
dim_head = ch // num_heads if use_spatial_transformer else num_head_channels
if exists(disable_self_attentions):
disabled_sa = disable_self_attentions[level]
else:
disabled_sa = False
if not exists(num_attention_blocks) or i < num_attention_blocks[level]:
layers.append(
get_attention_layer(
ch, num_heads, dim_head, depth=num_transformers, context_dim=context_dim,
disable_self_attn=disabled_sa, use_checkpoint=use_checkpoint
)
)
if level and i == self.num_res_blocks[level]:
out_ch = ch
layers.append(
get_resblock(
merge_factor=merge_factor,
merge_strategy=merge_strategy,
video_kernel_size=video_kernel_size,
ch=ch,
time_embed_dim=time_embed_dim,
dropout=dropout,
out_channels=out_ch,
dims=dims,
use_checkpoint=use_checkpoint,
use_scale_shift_norm=use_scale_shift_norm,
up=True,
dtype=self.dtype,
device=device,
operations=operations
)
if resblock_updown
else Upsample(ch, conv_resample, dims=dims, out_channels=out_ch, dtype=self.dtype, device=device, operations=operations)
)
ds //= 2
self.output_blocks.append(TimestepEmbedSequential(*layers))
self._feature_size += ch
self.out = nn.Sequential(
operations.GroupNorm(32, ch, dtype=self.dtype, device=device),
nn.SiLU(),
zero_module(operations.conv_nd(dims, model_channels, out_channels, 3, padding=1, dtype=self.dtype, device=device)),
)
if self.predict_codebook_ids:
self.id_predictor = nn.Sequential(
operations.GroupNorm(32, ch, dtype=self.dtype, device=device),
operations.conv_nd(dims, model_channels, n_embed, 1, dtype=self.dtype, device=device),
#nn.LogSoftmax(dim=1) # change to cross_entropy and produce non-normalized logits
)
def forward(self, x, timesteps=None, context=None, y=None, control=None, transformer_options={}, **kwargs):
"""
Apply the model to an input batch.
:param x: an [N x C x ...] Tensor of inputs.
:param timesteps: a 1-D batch of timesteps.
:param context: conditioning plugged in via crossattn
:param y: an [N] Tensor of labels, if class-conditional.
:return: an [N x C x ...] Tensor of outputs.
"""
transformer_options["original_shape"] = list(x.shape)
transformer_options["transformer_index"] = 0
transformer_patches = transformer_options.get("patches", {})
num_video_frames = kwargs.get("num_video_frames", self.default_num_video_frames)
image_only_indicator = kwargs.get("image_only_indicator", self.default_image_only_indicator)
time_context = kwargs.get("time_context", None)
assert (y is not None) == (
self.num_classes is not None
), "must specify y if and only if the model is class-conditional"
hs = []
t_emb = timestep_embedding(timesteps, self.model_channels, repeat_only=False).to(x.dtype)
emb = self.time_embed(t_emb)
if self.num_classes is not None:
assert y.shape[0] == x.shape[0]
emb = emb + self.label_emb(y)
h = x
for id, module in enumerate(self.input_blocks):
transformer_options["block"] = ("input", id)
h = forward_timestep_embed(module, h, emb, context, transformer_options, time_context=time_context, num_video_frames=num_video_frames, image_only_indicator=image_only_indicator)
h = apply_control(h, control, 'input')
if "input_block_patch" in transformer_patches:
patch = transformer_patches["input_block_patch"]
for p in patch:
h = p(h, transformer_options)
hs.append(h)
if "input_block_patch_after_skip" in transformer_patches:
patch = transformer_patches["input_block_patch_after_skip"]
for p in patch:
h = p(h, transformer_options)
transformer_options["block"] = ("middle", 0)
h = forward_timestep_embed(self.middle_block, h, emb, context, transformer_options, time_context=time_context, num_video_frames=num_video_frames, image_only_indicator=image_only_indicator)
h = apply_control(h, control, 'middle')
for id, module in enumerate(self.output_blocks):
transformer_options["block"] = ("output", id)
hsp = hs.pop()
hsp = apply_control(hsp, control, 'output')
if "output_block_patch" in transformer_patches:
patch = transformer_patches["output_block_patch"]
for p in patch:
h, hsp = p(h, hsp, transformer_options)
h = th.cat([h, hsp], dim=1)
del hsp
if len(hs) > 0:
output_shape = hs[-1].shape
else:
output_shape = None
h = forward_timestep_embed(module, h, emb, context, transformer_options, output_shape, time_context=time_context, num_video_frames=num_video_frames, image_only_indicator=image_only_indicator)
h = h.type(x.dtype)
if self.predict_codebook_ids:
return self.id_predictor(h)
else:
return self.out(h)

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import torch
import torch.nn as nn
import numpy as np
from functools import partial
from .util import extract_into_tensor, make_beta_schedule
from ldm_patched.ldm.util import default
class AbstractLowScaleModel(nn.Module):
# for concatenating a downsampled image to the latent representation
def __init__(self, noise_schedule_config=None):
super(AbstractLowScaleModel, self).__init__()
if noise_schedule_config is not None:
self.register_schedule(**noise_schedule_config)
def register_schedule(self, beta_schedule="linear", timesteps=1000,
linear_start=1e-4, linear_end=2e-2, cosine_s=8e-3):
betas = make_beta_schedule(beta_schedule, timesteps, linear_start=linear_start, linear_end=linear_end,
cosine_s=cosine_s)
alphas = 1. - betas
alphas_cumprod = np.cumprod(alphas, axis=0)
alphas_cumprod_prev = np.append(1., alphas_cumprod[:-1])
timesteps, = betas.shape
self.num_timesteps = int(timesteps)
self.linear_start = linear_start
self.linear_end = linear_end
assert alphas_cumprod.shape[0] == self.num_timesteps, 'alphas have to be defined for each timestep'
to_torch = partial(torch.tensor, dtype=torch.float32)
self.register_buffer('betas', to_torch(betas))
self.register_buffer('alphas_cumprod', to_torch(alphas_cumprod))
self.register_buffer('alphas_cumprod_prev', to_torch(alphas_cumprod_prev))
# calculations for diffusion q(x_t | x_{t-1}) and others
self.register_buffer('sqrt_alphas_cumprod', to_torch(np.sqrt(alphas_cumprod)))
self.register_buffer('sqrt_one_minus_alphas_cumprod', to_torch(np.sqrt(1. - alphas_cumprod)))
self.register_buffer('log_one_minus_alphas_cumprod', to_torch(np.log(1. - alphas_cumprod)))
self.register_buffer('sqrt_recip_alphas_cumprod', to_torch(np.sqrt(1. / alphas_cumprod)))
self.register_buffer('sqrt_recipm1_alphas_cumprod', to_torch(np.sqrt(1. / alphas_cumprod - 1)))
def q_sample(self, x_start, t, noise=None, seed=None):
if noise is None:
if seed is None:
noise = torch.randn_like(x_start)
else:
noise = torch.randn(x_start.size(), dtype=x_start.dtype, layout=x_start.layout, generator=torch.manual_seed(seed)).to(x_start.device)
return (extract_into_tensor(self.sqrt_alphas_cumprod.to(x_start.device), t, x_start.shape) * x_start +
extract_into_tensor(self.sqrt_one_minus_alphas_cumprod.to(x_start.device), t, x_start.shape) * noise)
def forward(self, x):
return x, None
def decode(self, x):
return x
class SimpleImageConcat(AbstractLowScaleModel):
# no noise level conditioning
def __init__(self):
super(SimpleImageConcat, self).__init__(noise_schedule_config=None)
self.max_noise_level = 0
def forward(self, x):
# fix to constant noise level
return x, torch.zeros(x.shape[0], device=x.device).long()
class ImageConcatWithNoiseAugmentation(AbstractLowScaleModel):
def __init__(self, noise_schedule_config, max_noise_level=1000, to_cuda=False):
super().__init__(noise_schedule_config=noise_schedule_config)
self.max_noise_level = max_noise_level
def forward(self, x, noise_level=None, seed=None):
if noise_level is None:
noise_level = torch.randint(0, self.max_noise_level, (x.shape[0],), device=x.device).long()
else:
assert isinstance(noise_level, torch.Tensor)
z = self.q_sample(x, noise_level, seed=seed)
return z, noise_level

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# adopted from
# https://github.com/openai/improved-diffusion/blob/main/improved_diffusion/gaussian_diffusion.py
# and
# https://github.com/lucidrains/denoising-diffusion-pytorch/blob/7706bdfc6f527f58d33f84b7b522e61e6e3164b3/denoising_diffusion_pytorch/denoising_diffusion_pytorch.py
# and
# https://github.com/openai/guided-diffusion/blob/0ba878e517b276c45d1195eb29f6f5f72659a05b/guided_diffusion/nn.py
#
# thanks!
import os
import math
import torch
import torch.nn as nn
import numpy as np
from einops import repeat, rearrange
from ldm_patched.ldm.util import instantiate_from_config
class AlphaBlender(nn.Module):
strategies = ["learned", "fixed", "learned_with_images"]
def __init__(
self,
alpha: float,
merge_strategy: str = "learned_with_images",
rearrange_pattern: str = "b t -> (b t) 1 1",
):
super().__init__()
self.merge_strategy = merge_strategy
self.rearrange_pattern = rearrange_pattern
assert (
merge_strategy in self.strategies
), f"merge_strategy needs to be in {self.strategies}"
if self.merge_strategy == "fixed":
self.register_buffer("mix_factor", torch.Tensor([alpha]))
elif (
self.merge_strategy == "learned"
or self.merge_strategy == "learned_with_images"
):
self.register_parameter(
"mix_factor", torch.nn.Parameter(torch.Tensor([alpha]))
)
else:
raise ValueError(f"unknown merge strategy {self.merge_strategy}")
def get_alpha(self, image_only_indicator: torch.Tensor) -> torch.Tensor:
# skip_time_mix = rearrange(repeat(skip_time_mix, 'b -> (b t) () () ()', t=t), '(b t) 1 ... -> b 1 t ...', t=t)
if self.merge_strategy == "fixed":
# make shape compatible
# alpha = repeat(self.mix_factor, '1 -> b () t () ()', t=t, b=bs)
alpha = self.mix_factor.to(image_only_indicator.device)
elif self.merge_strategy == "learned":
alpha = torch.sigmoid(self.mix_factor.to(image_only_indicator.device))
# make shape compatible
# alpha = repeat(alpha, '1 -> s () ()', s = t * bs)
elif self.merge_strategy == "learned_with_images":
assert image_only_indicator is not None, "need image_only_indicator ..."
alpha = torch.where(
image_only_indicator.bool(),
torch.ones(1, 1, device=image_only_indicator.device),
rearrange(torch.sigmoid(self.mix_factor.to(image_only_indicator.device)), "... -> ... 1"),
)
alpha = rearrange(alpha, self.rearrange_pattern)
# make shape compatible
# alpha = repeat(alpha, '1 -> s () ()', s = t * bs)
else:
raise NotImplementedError()
return alpha
def forward(
self,
x_spatial,
x_temporal,
image_only_indicator=None,
) -> torch.Tensor:
alpha = self.get_alpha(image_only_indicator)
x = (
alpha.to(x_spatial.dtype) * x_spatial
+ (1.0 - alpha).to(x_spatial.dtype) * x_temporal
)
return x
def make_beta_schedule(schedule, n_timestep, linear_start=1e-4, linear_end=2e-2, cosine_s=8e-3):
if schedule == "linear":
betas = (
torch.linspace(linear_start ** 0.5, linear_end ** 0.5, n_timestep, dtype=torch.float64) ** 2
)
elif schedule == "cosine":
timesteps = (
torch.arange(n_timestep + 1, dtype=torch.float64) / n_timestep + cosine_s
)
alphas = timesteps / (1 + cosine_s) * np.pi / 2
alphas = torch.cos(alphas).pow(2)
alphas = alphas / alphas[0]
betas = 1 - alphas[1:] / alphas[:-1]
betas = np.clip(betas, a_min=0, a_max=0.999)
elif schedule == "squaredcos_cap_v2": # used for karlo prior
# return early
return betas_for_alpha_bar(
n_timestep,
lambda t: math.cos((t + 0.008) / 1.008 * math.pi / 2) ** 2,
)
elif schedule == "sqrt_linear":
betas = torch.linspace(linear_start, linear_end, n_timestep, dtype=torch.float64)
elif schedule == "sqrt":
betas = torch.linspace(linear_start, linear_end, n_timestep, dtype=torch.float64) ** 0.5
else:
raise ValueError(f"schedule '{schedule}' unknown.")
return betas.numpy()
def make_ddim_timesteps(ddim_discr_method, num_ddim_timesteps, num_ddpm_timesteps, verbose=True):
if ddim_discr_method == 'uniform':
c = num_ddpm_timesteps // num_ddim_timesteps
ddim_timesteps = np.asarray(list(range(0, num_ddpm_timesteps, c)))
elif ddim_discr_method == 'quad':
ddim_timesteps = ((np.linspace(0, np.sqrt(num_ddpm_timesteps * .8), num_ddim_timesteps)) ** 2).astype(int)
else:
raise NotImplementedError(f'There is no ddim discretization method called "{ddim_discr_method}"')
# assert ddim_timesteps.shape[0] == num_ddim_timesteps
# add one to get the final alpha values right (the ones from first scale to data during sampling)
steps_out = ddim_timesteps + 1
if verbose:
print(f'Selected timesteps for ddim sampler: {steps_out}')
return steps_out
def make_ddim_sampling_parameters(alphacums, ddim_timesteps, eta, verbose=True):
# select alphas for computing the variance schedule
alphas = alphacums[ddim_timesteps]
alphas_prev = np.asarray([alphacums[0]] + alphacums[ddim_timesteps[:-1]].tolist())
# according the the formula provided in https://arxiv.org/abs/2010.02502
sigmas = eta * np.sqrt((1 - alphas_prev) / (1 - alphas) * (1 - alphas / alphas_prev))
if verbose:
print(f'Selected alphas for ddim sampler: a_t: {alphas}; a_(t-1): {alphas_prev}')
print(f'For the chosen value of eta, which is {eta}, '
f'this results in the following sigma_t schedule for ddim sampler {sigmas}')
return sigmas, alphas, alphas_prev
def betas_for_alpha_bar(num_diffusion_timesteps, alpha_bar, max_beta=0.999):
"""
Create a beta schedule that discretizes the given alpha_t_bar function,
which defines the cumulative product of (1-beta) over time from t = [0,1].
:param num_diffusion_timesteps: the number of betas to produce.
:param alpha_bar: a lambda that takes an argument t from 0 to 1 and
produces the cumulative product of (1-beta) up to that
part of the diffusion process.
:param max_beta: the maximum beta to use; use values lower than 1 to
prevent singularities.
"""
betas = []
for i in range(num_diffusion_timesteps):
t1 = i / num_diffusion_timesteps
t2 = (i + 1) / num_diffusion_timesteps
betas.append(min(1 - alpha_bar(t2) / alpha_bar(t1), max_beta))
return np.array(betas)
def extract_into_tensor(a, t, x_shape):
b, *_ = t.shape
out = a.gather(-1, t)
return out.reshape(b, *((1,) * (len(x_shape) - 1)))
def checkpoint(func, inputs, params, flag):
"""
Evaluate a function without caching intermediate activations, allowing for
reduced memory at the expense of extra compute in the backward pass.
:param func: the function to evaluate.
:param inputs: the argument sequence to pass to `func`.
:param params: a sequence of parameters `func` depends on but does not
explicitly take as arguments.
:param flag: if False, disable gradient checkpointing.
"""
if flag:
args = tuple(inputs) + tuple(params)
return CheckpointFunction.apply(func, len(inputs), *args)
else:
return func(*inputs)
class CheckpointFunction(torch.autograd.Function):
@staticmethod
def forward(ctx, run_function, length, *args):
ctx.run_function = run_function
ctx.input_tensors = list(args[:length])
ctx.input_params = list(args[length:])
ctx.gpu_autocast_kwargs = {"enabled": torch.is_autocast_enabled(),
"dtype": torch.get_autocast_gpu_dtype(),
"cache_enabled": torch.is_autocast_cache_enabled()}
with torch.no_grad():
output_tensors = ctx.run_function(*ctx.input_tensors)
return output_tensors
@staticmethod
def backward(ctx, *output_grads):
ctx.input_tensors = [x.detach().requires_grad_(True) for x in ctx.input_tensors]
with torch.enable_grad(), \
torch.cuda.amp.autocast(**ctx.gpu_autocast_kwargs):
# Fixes a bug where the first op in run_function modifies the
# Tensor storage in place, which is not allowed for detach()'d
# Tensors.
shallow_copies = [x.view_as(x) for x in ctx.input_tensors]
output_tensors = ctx.run_function(*shallow_copies)
input_grads = torch.autograd.grad(
output_tensors,
ctx.input_tensors + ctx.input_params,
output_grads,
allow_unused=True,
)
del ctx.input_tensors
del ctx.input_params
del output_tensors
return (None, None) + input_grads
def timestep_embedding(timesteps, dim, max_period=10000, repeat_only=False):
"""
Create sinusoidal timestep embeddings.
:param timesteps: a 1-D Tensor of N indices, one per batch element.
These may be fractional.
:param dim: the dimension of the output.
:param max_period: controls the minimum frequency of the embeddings.
:return: an [N x dim] Tensor of positional embeddings.
"""
if not repeat_only:
half = dim // 2
freqs = torch.exp(
-math.log(max_period) * torch.arange(start=0, end=half, dtype=torch.float32, device=timesteps.device) / half
)
args = timesteps[:, 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)
else:
embedding = repeat(timesteps, 'b -> b d', d=dim)
return embedding
def zero_module(module):
"""
Zero out the parameters of a module and return it.
"""
for p in module.parameters():
p.detach().zero_()
return module
def scale_module(module, scale):
"""
Scale the parameters of a module and return it.
"""
for p in module.parameters():
p.detach().mul_(scale)
return module
def mean_flat(tensor):
"""
Take the mean over all non-batch dimensions.
"""
return tensor.mean(dim=list(range(1, len(tensor.shape))))
def avg_pool_nd(dims, *args, **kwargs):
"""
Create a 1D, 2D, or 3D average pooling module.
"""
if dims == 1:
return nn.AvgPool1d(*args, **kwargs)
elif dims == 2:
return nn.AvgPool2d(*args, **kwargs)
elif dims == 3:
return nn.AvgPool3d(*args, **kwargs)
raise ValueError(f"unsupported dimensions: {dims}")
class HybridConditioner(nn.Module):
def __init__(self, c_concat_config, c_crossattn_config):
super().__init__()
self.concat_conditioner = instantiate_from_config(c_concat_config)
self.crossattn_conditioner = instantiate_from_config(c_crossattn_config)
def forward(self, c_concat, c_crossattn):
c_concat = self.concat_conditioner(c_concat)
c_crossattn = self.crossattn_conditioner(c_crossattn)
return {'c_concat': [c_concat], 'c_crossattn': [c_crossattn]}
def noise_like(shape, device, repeat=False):
repeat_noise = lambda: torch.randn((1, *shape[1:]), device=device).repeat(shape[0], *((1,) * (len(shape) - 1)))
noise = lambda: torch.randn(shape, device=device)
return repeat_noise() if repeat else noise()

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import torch
import numpy as np
class AbstractDistribution:
def sample(self):
raise NotImplementedError()
def mode(self):
raise NotImplementedError()
class DiracDistribution(AbstractDistribution):
def __init__(self, value):
self.value = value
def sample(self):
return self.value
def mode(self):
return self.value
class DiagonalGaussianDistribution(object):
def __init__(self, parameters, deterministic=False):
self.parameters = parameters
self.mean, self.logvar = torch.chunk(parameters, 2, dim=1)
self.logvar = torch.clamp(self.logvar, -30.0, 20.0)
self.deterministic = deterministic
self.std = torch.exp(0.5 * self.logvar)
self.var = torch.exp(self.logvar)
if self.deterministic:
self.var = self.std = torch.zeros_like(self.mean).to(device=self.parameters.device)
def sample(self):
x = self.mean + self.std * torch.randn(self.mean.shape).to(device=self.parameters.device)
return x
def kl(self, other=None):
if self.deterministic:
return torch.Tensor([0.])
else:
if other is None:
return 0.5 * torch.sum(torch.pow(self.mean, 2)
+ self.var - 1.0 - self.logvar,
dim=[1, 2, 3])
else:
return 0.5 * torch.sum(
torch.pow(self.mean - other.mean, 2) / other.var
+ self.var / other.var - 1.0 - self.logvar + other.logvar,
dim=[1, 2, 3])
def nll(self, sample, dims=[1,2,3]):
if self.deterministic:
return torch.Tensor([0.])
logtwopi = np.log(2.0 * np.pi)
return 0.5 * torch.sum(
logtwopi + self.logvar + torch.pow(sample - self.mean, 2) / self.var,
dim=dims)
def mode(self):
return self.mean
def normal_kl(mean1, logvar1, mean2, logvar2):
"""
source: https://github.com/openai/guided-diffusion/blob/27c20a8fab9cb472df5d6bdd6c8d11c8f430b924/guided_diffusion/losses.py#L12
Compute the KL divergence between two gaussians.
Shapes are automatically broadcasted, so batches can be compared to
scalars, among other use cases.
"""
tensor = None
for obj in (mean1, logvar1, mean2, logvar2):
if isinstance(obj, torch.Tensor):
tensor = obj
break
assert tensor is not None, "at least one argument must be a Tensor"
# Force variances to be Tensors. Broadcasting helps convert scalars to
# Tensors, but it does not work for torch.exp().
logvar1, logvar2 = [
x if isinstance(x, torch.Tensor) else torch.tensor(x).to(tensor)
for x in (logvar1, logvar2)
]
return 0.5 * (
-1.0
+ logvar2
- logvar1
+ torch.exp(logvar1 - logvar2)
+ ((mean1 - mean2) ** 2) * torch.exp(-logvar2)
)

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import torch
from torch import nn
class LitEma(nn.Module):
def __init__(self, model, decay=0.9999, use_num_upates=True):
super().__init__()
if decay < 0.0 or decay > 1.0:
raise ValueError('Decay must be between 0 and 1')
self.m_name2s_name = {}
self.register_buffer('decay', torch.tensor(decay, dtype=torch.float32))
self.register_buffer('num_updates', torch.tensor(0, dtype=torch.int) if use_num_upates
else torch.tensor(-1, dtype=torch.int))
for name, p in model.named_parameters():
if p.requires_grad:
# remove as '.'-character is not allowed in buffers
s_name = name.replace('.', '')
self.m_name2s_name.update({name: s_name})
self.register_buffer(s_name, p.clone().detach().data)
self.collected_params = []
def reset_num_updates(self):
del self.num_updates
self.register_buffer('num_updates', torch.tensor(0, dtype=torch.int))
def forward(self, model):
decay = self.decay
if self.num_updates >= 0:
self.num_updates += 1
decay = min(self.decay, (1 + self.num_updates) / (10 + self.num_updates))
one_minus_decay = 1.0 - decay
with torch.no_grad():
m_param = dict(model.named_parameters())
shadow_params = dict(self.named_buffers())
for key in m_param:
if m_param[key].requires_grad:
sname = self.m_name2s_name[key]
shadow_params[sname] = shadow_params[sname].type_as(m_param[key])
shadow_params[sname].sub_(one_minus_decay * (shadow_params[sname] - m_param[key]))
else:
assert not key in self.m_name2s_name
def copy_to(self, model):
m_param = dict(model.named_parameters())
shadow_params = dict(self.named_buffers())
for key in m_param:
if m_param[key].requires_grad:
m_param[key].data.copy_(shadow_params[self.m_name2s_name[key]].data)
else:
assert not key in self.m_name2s_name
def store(self, parameters):
"""
Save the current parameters for restoring later.
Args:
parameters: Iterable of `torch.nn.Parameter`; the parameters to be
temporarily stored.
"""
self.collected_params = [param.clone() for param in parameters]
def restore(self, parameters):
"""
Restore the parameters stored with the `store` method.
Useful to validate the model with EMA parameters without affecting the
original optimization process. Store the parameters before the
`copy_to` method. After validation (or model saving), use this to
restore the former parameters.
Args:
parameters: Iterable of `torch.nn.Parameter`; the parameters to be
updated with the stored parameters.
"""
for c_param, param in zip(self.collected_params, parameters):
param.data.copy_(c_param.data)

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from ..diffusionmodules.upscaling import ImageConcatWithNoiseAugmentation
from ..diffusionmodules.openaimodel import Timestep
import torch
class CLIPEmbeddingNoiseAugmentation(ImageConcatWithNoiseAugmentation):
def __init__(self, *args, clip_stats_path=None, timestep_dim=256, **kwargs):
super().__init__(*args, **kwargs)
if clip_stats_path is None:
clip_mean, clip_std = torch.zeros(timestep_dim), torch.ones(timestep_dim)
else:
clip_mean, clip_std = torch.load(clip_stats_path, map_location="cpu")
self.register_buffer("data_mean", clip_mean[None, :], persistent=False)
self.register_buffer("data_std", clip_std[None, :], persistent=False)
self.time_embed = Timestep(timestep_dim)
def scale(self, x):
# re-normalize to centered mean and unit variance
x = (x - self.data_mean.to(x.device)) * 1. / self.data_std.to(x.device)
return x
def unscale(self, x):
# back to original data stats
x = (x * self.data_std.to(x.device)) + self.data_mean.to(x.device)
return x
def forward(self, x, noise_level=None, seed=None):
if noise_level is None:
noise_level = torch.randint(0, self.max_noise_level, (x.shape[0],), device=x.device).long()
else:
assert isinstance(noise_level, torch.Tensor)
x = self.scale(x)
z = self.q_sample(x, noise_level, seed=seed)
z = self.unscale(z)
noise_level = self.time_embed(noise_level)
return z, noise_level

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# original source:
# https://github.com/AminRezaei0x443/memory-efficient-attention/blob/1bc0d9e6ac5f82ea43a375135c4e1d3896ee1694/memory_efficient_attention/attention_torch.py
# license:
# MIT
# credit:
# Amin Rezaei (original author)
# Alex Birch (optimized algorithm for 3D tensors, at the expense of removing bias, masking and callbacks)
# implementation of:
# Self-attention Does Not Need O(n2) Memory":
# https://arxiv.org/abs/2112.05682v2
from functools import partial
import torch
from torch import Tensor
from torch.utils.checkpoint import checkpoint
import math
try:
from typing import Optional, NamedTuple, List, Protocol
except ImportError:
from typing import Optional, NamedTuple, List
from typing_extensions import Protocol
from torch import Tensor
from typing import List
from ldm_patched.modules import model_management
def dynamic_slice(
x: Tensor,
starts: List[int],
sizes: List[int],
) -> Tensor:
slicing = [slice(start, start + size) for start, size in zip(starts, sizes)]
return x[slicing]
class AttnChunk(NamedTuple):
exp_values: Tensor
exp_weights_sum: Tensor
max_score: Tensor
class SummarizeChunk(Protocol):
@staticmethod
def __call__(
query: Tensor,
key_t: Tensor,
value: Tensor,
) -> AttnChunk: ...
class ComputeQueryChunkAttn(Protocol):
@staticmethod
def __call__(
query: Tensor,
key_t: Tensor,
value: Tensor,
) -> Tensor: ...
def _summarize_chunk(
query: Tensor,
key_t: Tensor,
value: Tensor,
scale: float,
upcast_attention: bool,
mask,
) -> AttnChunk:
if upcast_attention:
with torch.autocast(enabled=False, device_type = 'cuda'):
query = query.float()
key_t = key_t.float()
attn_weights = torch.baddbmm(
torch.empty(1, 1, 1, device=query.device, dtype=query.dtype),
query,
key_t,
alpha=scale,
beta=0,
)
else:
attn_weights = torch.baddbmm(
torch.empty(1, 1, 1, device=query.device, dtype=query.dtype),
query,
key_t,
alpha=scale,
beta=0,
)
max_score, _ = torch.max(attn_weights, -1, keepdim=True)
max_score = max_score.detach()
attn_weights -= max_score
if mask is not None:
attn_weights += mask
torch.exp(attn_weights, out=attn_weights)
exp_weights = attn_weights.to(value.dtype)
exp_values = torch.bmm(exp_weights, value)
max_score = max_score.squeeze(-1)
return AttnChunk(exp_values, exp_weights.sum(dim=-1), max_score)
def _query_chunk_attention(
query: Tensor,
key_t: Tensor,
value: Tensor,
summarize_chunk: SummarizeChunk,
kv_chunk_size: int,
mask,
) -> Tensor:
batch_x_heads, k_channels_per_head, k_tokens = key_t.shape
_, _, v_channels_per_head = value.shape
def chunk_scanner(chunk_idx: int, mask) -> AttnChunk:
key_chunk = dynamic_slice(
key_t,
(0, 0, chunk_idx),
(batch_x_heads, k_channels_per_head, kv_chunk_size)
)
value_chunk = dynamic_slice(
value,
(0, chunk_idx, 0),
(batch_x_heads, kv_chunk_size, v_channels_per_head)
)
if mask is not None:
mask = mask[:,:,chunk_idx:chunk_idx + kv_chunk_size]
return summarize_chunk(query, key_chunk, value_chunk, mask=mask)
chunks: List[AttnChunk] = [
chunk_scanner(chunk, mask) for chunk in torch.arange(0, k_tokens, kv_chunk_size)
]
acc_chunk = AttnChunk(*map(torch.stack, zip(*chunks)))
chunk_values, chunk_weights, chunk_max = acc_chunk
global_max, _ = torch.max(chunk_max, 0, keepdim=True)
max_diffs = torch.exp(chunk_max - global_max)
chunk_values *= torch.unsqueeze(max_diffs, -1)
chunk_weights *= max_diffs
all_values = chunk_values.sum(dim=0)
all_weights = torch.unsqueeze(chunk_weights, -1).sum(dim=0)
return all_values / all_weights
# TODO: refactor CrossAttention#get_attention_scores to share code with this
def _get_attention_scores_no_kv_chunking(
query: Tensor,
key_t: Tensor,
value: Tensor,
scale: float,
upcast_attention: bool,
mask,
) -> Tensor:
if upcast_attention:
with torch.autocast(enabled=False, device_type = 'cuda'):
query = query.float()
key_t = key_t.float()
attn_scores = torch.baddbmm(
torch.empty(1, 1, 1, device=query.device, dtype=query.dtype),
query,
key_t,
alpha=scale,
beta=0,
)
else:
attn_scores = torch.baddbmm(
torch.empty(1, 1, 1, device=query.device, dtype=query.dtype),
query,
key_t,
alpha=scale,
beta=0,
)
if mask is not None:
attn_scores += mask
try:
attn_probs = attn_scores.softmax(dim=-1)
del attn_scores
except model_management.OOM_EXCEPTION:
print("ran out of memory while running softmax in _get_attention_scores_no_kv_chunking, trying slower in place softmax instead")
attn_scores -= attn_scores.max(dim=-1, keepdim=True).values
torch.exp(attn_scores, out=attn_scores)
summed = torch.sum(attn_scores, dim=-1, keepdim=True)
attn_scores /= summed
attn_probs = attn_scores
hidden_states_slice = torch.bmm(attn_probs.to(value.dtype), value)
return hidden_states_slice
class ScannedChunk(NamedTuple):
chunk_idx: int
attn_chunk: AttnChunk
def efficient_dot_product_attention(
query: Tensor,
key_t: Tensor,
value: Tensor,
query_chunk_size=1024,
kv_chunk_size: Optional[int] = None,
kv_chunk_size_min: Optional[int] = None,
use_checkpoint=True,
upcast_attention=False,
mask = None,
):
"""Computes efficient dot-product attention given query, transposed key, and value.
This is efficient version of attention presented in
https://arxiv.org/abs/2112.05682v2 which comes with O(sqrt(n)) memory requirements.
Args:
query: queries for calculating attention with shape of
`[batch * num_heads, tokens, channels_per_head]`.
key_t: keys for calculating attention with shape of
`[batch * num_heads, channels_per_head, tokens]`.
value: values to be used in attention with shape of
`[batch * num_heads, tokens, channels_per_head]`.
query_chunk_size: int: query chunks size
kv_chunk_size: Optional[int]: key/value chunks size. if None: defaults to sqrt(key_tokens)
kv_chunk_size_min: Optional[int]: key/value minimum chunk size. only considered when kv_chunk_size is None. changes `sqrt(key_tokens)` into `max(sqrt(key_tokens), kv_chunk_size_min)`, to ensure our chunk sizes don't get too small (smaller chunks = more chunks = less concurrent work done).
use_checkpoint: bool: whether to use checkpointing (recommended True for training, False for inference)
Returns:
Output of shape `[batch * num_heads, query_tokens, channels_per_head]`.
"""
batch_x_heads, q_tokens, q_channels_per_head = query.shape
_, _, k_tokens = key_t.shape
scale = q_channels_per_head ** -0.5
kv_chunk_size = min(kv_chunk_size or int(math.sqrt(k_tokens)), k_tokens)
if kv_chunk_size_min is not None:
kv_chunk_size = max(kv_chunk_size, kv_chunk_size_min)
if mask is not None and len(mask.shape) == 2:
mask = mask.unsqueeze(0)
def get_query_chunk(chunk_idx: int) -> Tensor:
return dynamic_slice(
query,
(0, chunk_idx, 0),
(batch_x_heads, min(query_chunk_size, q_tokens), q_channels_per_head)
)
def get_mask_chunk(chunk_idx: int) -> Tensor:
if mask is None:
return None
chunk = min(query_chunk_size, q_tokens)
return mask[:,chunk_idx:chunk_idx + chunk]
summarize_chunk: SummarizeChunk = partial(_summarize_chunk, scale=scale, upcast_attention=upcast_attention)
summarize_chunk: SummarizeChunk = partial(checkpoint, summarize_chunk) if use_checkpoint else summarize_chunk
compute_query_chunk_attn: ComputeQueryChunkAttn = partial(
_get_attention_scores_no_kv_chunking,
scale=scale,
upcast_attention=upcast_attention
) if k_tokens <= kv_chunk_size else (
# fast-path for when there's just 1 key-value chunk per query chunk (this is just sliced attention btw)
partial(
_query_chunk_attention,
kv_chunk_size=kv_chunk_size,
summarize_chunk=summarize_chunk,
)
)
if q_tokens <= query_chunk_size:
# fast-path for when there's just 1 query chunk
return compute_query_chunk_attn(
query=query,
key_t=key_t,
value=value,
mask=mask,
)
# TODO: maybe we should use torch.empty_like(query) to allocate storage in-advance,
# and pass slices to be mutated, instead of torch.cat()ing the returned slices
res = torch.cat([
compute_query_chunk_attn(
query=get_query_chunk(i * query_chunk_size),
key_t=key_t,
value=value,
mask=get_mask_chunk(i * query_chunk_size)
) for i in range(math.ceil(q_tokens / query_chunk_size))
], dim=1)
return res

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import functools
from typing import Callable, Iterable, Union
import torch
from einops import rearrange, repeat
import ldm_patched.modules.ops
ops = ldm_patched.modules.ops.disable_weight_init
from .diffusionmodules.model import (
AttnBlock,
Decoder,
ResnetBlock,
)
from .diffusionmodules.openaimodel import ResBlock, timestep_embedding
from .attention import BasicTransformerBlock
def partialclass(cls, *args, **kwargs):
class NewCls(cls):
__init__ = functools.partialmethod(cls.__init__, *args, **kwargs)
return NewCls
class VideoResBlock(ResnetBlock):
def __init__(
self,
out_channels,
*args,
dropout=0.0,
video_kernel_size=3,
alpha=0.0,
merge_strategy="learned",
**kwargs,
):
super().__init__(out_channels=out_channels, dropout=dropout, *args, **kwargs)
if video_kernel_size is None:
video_kernel_size = [3, 1, 1]
self.time_stack = ResBlock(
channels=out_channels,
emb_channels=0,
dropout=dropout,
dims=3,
use_scale_shift_norm=False,
use_conv=False,
up=False,
down=False,
kernel_size=video_kernel_size,
use_checkpoint=False,
skip_t_emb=True,
)
self.merge_strategy = merge_strategy
if self.merge_strategy == "fixed":
self.register_buffer("mix_factor", torch.Tensor([alpha]))
elif self.merge_strategy == "learned":
self.register_parameter(
"mix_factor", torch.nn.Parameter(torch.Tensor([alpha]))
)
else:
raise ValueError(f"unknown merge strategy {self.merge_strategy}")
def get_alpha(self, bs):
if self.merge_strategy == "fixed":
return self.mix_factor
elif self.merge_strategy == "learned":
return torch.sigmoid(self.mix_factor)
else:
raise NotImplementedError()
def forward(self, x, temb, skip_video=False, timesteps=None):
b, c, h, w = x.shape
if timesteps is None:
timesteps = b
x = super().forward(x, temb)
if not skip_video:
x_mix = rearrange(x, "(b t) c h w -> b c t h w", t=timesteps)
x = rearrange(x, "(b t) c h w -> b c t h w", t=timesteps)
x = self.time_stack(x, temb)
alpha = self.get_alpha(bs=b // timesteps).to(x.device)
x = alpha * x + (1.0 - alpha) * x_mix
x = rearrange(x, "b c t h w -> (b t) c h w")
return x
class AE3DConv(ops.Conv2d):
def __init__(self, in_channels, out_channels, video_kernel_size=3, *args, **kwargs):
super().__init__(in_channels, out_channels, *args, **kwargs)
if isinstance(video_kernel_size, Iterable):
padding = [int(k // 2) for k in video_kernel_size]
else:
padding = int(video_kernel_size // 2)
self.time_mix_conv = ops.Conv3d(
in_channels=out_channels,
out_channels=out_channels,
kernel_size=video_kernel_size,
padding=padding,
)
def forward(self, input, timesteps=None, skip_video=False):
if timesteps is None:
timesteps = input.shape[0]
x = super().forward(input)
if skip_video:
return x
x = rearrange(x, "(b t) c h w -> b c t h w", t=timesteps)
x = self.time_mix_conv(x)
return rearrange(x, "b c t h w -> (b t) c h w")
class AttnVideoBlock(AttnBlock):
def __init__(
self, in_channels: int, alpha: float = 0, merge_strategy: str = "learned"
):
super().__init__(in_channels)
# no context, single headed, as in base class
self.time_mix_block = BasicTransformerBlock(
dim=in_channels,
n_heads=1,
d_head=in_channels,
checkpoint=False,
ff_in=True,
)
time_embed_dim = self.in_channels * 4
self.video_time_embed = torch.nn.Sequential(
ops.Linear(self.in_channels, time_embed_dim),
torch.nn.SiLU(),
ops.Linear(time_embed_dim, self.in_channels),
)
self.merge_strategy = merge_strategy
if self.merge_strategy == "fixed":
self.register_buffer("mix_factor", torch.Tensor([alpha]))
elif self.merge_strategy == "learned":
self.register_parameter(
"mix_factor", torch.nn.Parameter(torch.Tensor([alpha]))
)
else:
raise ValueError(f"unknown merge strategy {self.merge_strategy}")
def forward(self, x, timesteps=None, skip_time_block=False):
if skip_time_block:
return super().forward(x)
if timesteps is None:
timesteps = x.shape[0]
x_in = x
x = self.attention(x)
h, w = x.shape[2:]
x = rearrange(x, "b c h w -> b (h w) c")
x_mix = x
num_frames = torch.arange(timesteps, device=x.device)
num_frames = repeat(num_frames, "t -> b t", b=x.shape[0] // timesteps)
num_frames = rearrange(num_frames, "b t -> (b t)")
t_emb = timestep_embedding(num_frames, self.in_channels, repeat_only=False)
emb = self.video_time_embed(t_emb) # b, n_channels
emb = emb[:, None, :]
x_mix = x_mix + emb
alpha = self.get_alpha().to(x.device)
x_mix = self.time_mix_block(x_mix, timesteps=timesteps)
x = alpha * x + (1.0 - alpha) * x_mix # alpha merge
x = rearrange(x, "b (h w) c -> b c h w", h=h, w=w)
x = self.proj_out(x)
return x_in + x
def get_alpha(
self,
):
if self.merge_strategy == "fixed":
return self.mix_factor
elif self.merge_strategy == "learned":
return torch.sigmoid(self.mix_factor)
else:
raise NotImplementedError(f"unknown merge strategy {self.merge_strategy}")
def make_time_attn(
in_channels,
attn_type="vanilla",
attn_kwargs=None,
alpha: float = 0,
merge_strategy: str = "learned",
):
return partialclass(
AttnVideoBlock, in_channels, alpha=alpha, merge_strategy=merge_strategy
)
class Conv2DWrapper(torch.nn.Conv2d):
def forward(self, input: torch.Tensor, **kwargs) -> torch.Tensor:
return super().forward(input)
class VideoDecoder(Decoder):
available_time_modes = ["all", "conv-only", "attn-only"]
def __init__(
self,
*args,
video_kernel_size: Union[int, list] = 3,
alpha: float = 0.0,
merge_strategy: str = "learned",
time_mode: str = "conv-only",
**kwargs,
):
self.video_kernel_size = video_kernel_size
self.alpha = alpha
self.merge_strategy = merge_strategy
self.time_mode = time_mode
assert (
self.time_mode in self.available_time_modes
), f"time_mode parameter has to be in {self.available_time_modes}"
if self.time_mode != "attn-only":
kwargs["conv_out_op"] = partialclass(AE3DConv, video_kernel_size=self.video_kernel_size)
if self.time_mode not in ["conv-only", "only-last-conv"]:
kwargs["attn_op"] = partialclass(make_time_attn, alpha=self.alpha, merge_strategy=self.merge_strategy)
if self.time_mode not in ["attn-only", "only-last-conv"]:
kwargs["resnet_op"] = partialclass(VideoResBlock, video_kernel_size=self.video_kernel_size, alpha=self.alpha, merge_strategy=self.merge_strategy)
super().__init__(*args, **kwargs)
def get_last_layer(self, skip_time_mix=False, **kwargs):
if self.time_mode == "attn-only":
raise NotImplementedError("TODO")
else:
return (
self.conv_out.time_mix_conv.weight
if not skip_time_mix
else self.conv_out.weight
)

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ldm_patched/ldm/util.py Normal file
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@@ -0,0 +1,197 @@
import importlib
import torch
from torch import optim
import numpy as np
from inspect import isfunction
from PIL import Image, ImageDraw, ImageFont
def log_txt_as_img(wh, xc, size=10):
# wh a tuple of (width, height)
# xc a list of captions to plot
b = len(xc)
txts = list()
for bi in range(b):
txt = Image.new("RGB", wh, color="white")
draw = ImageDraw.Draw(txt)
font = ImageFont.truetype('data/DejaVuSans.ttf', size=size)
nc = int(40 * (wh[0] / 256))
lines = "\n".join(xc[bi][start:start + nc] for start in range(0, len(xc[bi]), nc))
try:
draw.text((0, 0), lines, fill="black", font=font)
except UnicodeEncodeError:
print("Cant encode string for logging. Skipping.")
txt = np.array(txt).transpose(2, 0, 1) / 127.5 - 1.0
txts.append(txt)
txts = np.stack(txts)
txts = torch.tensor(txts)
return txts
def ismap(x):
if not isinstance(x, torch.Tensor):
return False
return (len(x.shape) == 4) and (x.shape[1] > 3)
def isimage(x):
if not isinstance(x,torch.Tensor):
return False
return (len(x.shape) == 4) and (x.shape[1] == 3 or x.shape[1] == 1)
def exists(x):
return x is not None
def default(val, d):
if exists(val):
return val
return d() if isfunction(d) else d
def mean_flat(tensor):
"""
https://github.com/openai/guided-diffusion/blob/27c20a8fab9cb472df5d6bdd6c8d11c8f430b924/guided_diffusion/nn.py#L86
Take the mean over all non-batch dimensions.
"""
return tensor.mean(dim=list(range(1, len(tensor.shape))))
def count_params(model, verbose=False):
total_params = sum(p.numel() for p in model.parameters())
if verbose:
print(f"{model.__class__.__name__} has {total_params*1.e-6:.2f} M params.")
return total_params
def instantiate_from_config(config):
if not "target" in config:
if config == '__is_first_stage__':
return None
elif config == "__is_unconditional__":
return None
raise KeyError("Expected key `target` to instantiate.")
return get_obj_from_str(config["target"])(**config.get("params", dict()))
def get_obj_from_str(string, reload=False):
module, cls = string.rsplit(".", 1)
if reload:
module_imp = importlib.import_module(module)
importlib.reload(module_imp)
return getattr(importlib.import_module(module, package=None), cls)
class AdamWwithEMAandWings(optim.Optimizer):
# credit to https://gist.github.com/crowsonkb/65f7265353f403714fce3b2595e0b298
def __init__(self, params, lr=1.e-3, betas=(0.9, 0.999), eps=1.e-8, # TODO: check hyperparameters before using
weight_decay=1.e-2, amsgrad=False, ema_decay=0.9999, # ema decay to match previous code
ema_power=1., param_names=()):
"""AdamW that saves EMA versions of the parameters."""
if not 0.0 <= lr:
raise ValueError("Invalid learning rate: {}".format(lr))
if not 0.0 <= eps:
raise ValueError("Invalid epsilon value: {}".format(eps))
if not 0.0 <= betas[0] < 1.0:
raise ValueError("Invalid beta parameter at index 0: {}".format(betas[0]))
if not 0.0 <= betas[1] < 1.0:
raise ValueError("Invalid beta parameter at index 1: {}".format(betas[1]))
if not 0.0 <= weight_decay:
raise ValueError("Invalid weight_decay value: {}".format(weight_decay))
if not 0.0 <= ema_decay <= 1.0:
raise ValueError("Invalid ema_decay value: {}".format(ema_decay))
defaults = dict(lr=lr, betas=betas, eps=eps,
weight_decay=weight_decay, amsgrad=amsgrad, ema_decay=ema_decay,
ema_power=ema_power, param_names=param_names)
super().__init__(params, defaults)
def __setstate__(self, state):
super().__setstate__(state)
for group in self.param_groups:
group.setdefault('amsgrad', False)
@torch.no_grad()
def step(self, closure=None):
"""Performs a single optimization step.
Args:
closure (callable, optional): A closure that reevaluates the model
and returns the loss.
"""
loss = None
if closure is not None:
with torch.enable_grad():
loss = closure()
for group in self.param_groups:
params_with_grad = []
grads = []
exp_avgs = []
exp_avg_sqs = []
ema_params_with_grad = []
state_sums = []
max_exp_avg_sqs = []
state_steps = []
amsgrad = group['amsgrad']
beta1, beta2 = group['betas']
ema_decay = group['ema_decay']
ema_power = group['ema_power']
for p in group['params']:
if p.grad is None:
continue
params_with_grad.append(p)
if p.grad.is_sparse:
raise RuntimeError('AdamW does not support sparse gradients')
grads.append(p.grad)
state = self.state[p]
# State initialization
if len(state) == 0:
state['step'] = 0
# Exponential moving average of gradient values
state['exp_avg'] = torch.zeros_like(p, memory_format=torch.preserve_format)
# Exponential moving average of squared gradient values
state['exp_avg_sq'] = torch.zeros_like(p, memory_format=torch.preserve_format)
if amsgrad:
# Maintains max of all exp. moving avg. of sq. grad. values
state['max_exp_avg_sq'] = torch.zeros_like(p, memory_format=torch.preserve_format)
# Exponential moving average of parameter values
state['param_exp_avg'] = p.detach().float().clone()
exp_avgs.append(state['exp_avg'])
exp_avg_sqs.append(state['exp_avg_sq'])
ema_params_with_grad.append(state['param_exp_avg'])
if amsgrad:
max_exp_avg_sqs.append(state['max_exp_avg_sq'])
# update the steps for each param group update
state['step'] += 1
# record the step after step update
state_steps.append(state['step'])
optim._functional.adamw(params_with_grad,
grads,
exp_avgs,
exp_avg_sqs,
max_exp_avg_sqs,
state_steps,
amsgrad=amsgrad,
beta1=beta1,
beta2=beta2,
lr=group['lr'],
weight_decay=group['weight_decay'],
eps=group['eps'],
maximize=False)
cur_ema_decay = min(ema_decay, 1 - state['step'] ** -ema_power)
for param, ema_param in zip(params_with_grad, ema_params_with_grad):
ema_param.mul_(cur_ema_decay).add_(param.float(), alpha=1 - cur_ema_decay)
return loss