├── cm
├── __init__.py
├── losses.py
├── dist_util.py
├── nn.py
├── image_datasets.py
├── random_util.py
├── resample.py
├── fp16_util.py
├── script_util.py
├── logger.py
├── train_util.py
├── unet.py
└── network.py
├── assets
└── imagenet64.png
├── .gitignore
├── setup.py
├── LICENSE
├── scripts
├── fid_eval.sh
├── distill_pid_diffusion.sh
├── image_sampling.sh
├── image_sample.py
├── cm_train.py
└── fid_evaluation.py
└── README.md
/cm/__init__.py:
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1 | """
2 | Codebase for "Improved Denoising Diffusion Probabilistic Models".
3 | """
4 |
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/assets/imagenet64.png:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/pantheon5100/pid_diffusion/HEAD/assets/imagenet64.png
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/.gitignore:
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1 | # Compiled python modules.
2 | *.pyc
3 | /cifar10
4 | /.hypothesis
5 |
6 | # Byte-compiled
7 | _pycache__/
8 | .cache/
9 | .idea/
10 |
11 | # Python egg metadata, regenerated from source files by setuptools.
12 | /*.egg-info
13 | .eggs/
14 |
15 | # PyPI distribution artifacts.
16 | build/
17 | dist/
18 |
19 | # Tests
20 | .pytest_cache/
21 |
22 | # Other
23 | *.DS_Store
24 |
25 | /experiment
26 | /model_zoo/
27 | /evaluations/*.npz
28 |
29 | /evaluations/cifar_img_fid
30 | /evaluations/classify_image_graph_def.pb
31 |
32 | !/model_zoo/README.md
33 |
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/setup.py:
--------------------------------------------------------------------------------
1 | from setuptools import setup
2 |
3 | setup(
4 | name="consistency-models",
5 | py_modules=["cm", "evaluations"],
6 | install_requires=[
7 | "blobfile>=1.0.5",
8 | "torch",
9 | "clean-fid",
10 | "tqdm",
11 | "numpy",
12 | "scipy",
13 | "pandas",
14 | "Cython",
15 | "piq==0.7.0",
16 | "joblib==0.14.0",
17 | "albumentations==0.4.3",
18 | "lmdb",
19 | "clip @ git+https://github.com/openai/CLIP.git",
20 | "flash-attn==0.2.8",
21 | "pillow",
22 | ],
23 | )
24 |
--------------------------------------------------------------------------------
/LICENSE:
--------------------------------------------------------------------------------
1 | MIT License
2 |
3 | Copyright (c) 2024 Zak
4 |
5 | Permission is hereby granted, free of charge, to any person obtaining a copy
6 | of this software and associated documentation files (the "Software"), to deal
7 | in the Software without restriction, including without limitation the rights
8 | to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
9 | copies of the Software, and to permit persons to whom the Software is
10 | furnished to do so, subject to the following conditions:
11 |
12 | The above copyright notice and this permission notice shall be included in all
13 | copies or substantial portions of the Software.
14 |
15 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 | IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 | FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 | AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 | LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20 | OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21 | SOFTWARE.
22 |
--------------------------------------------------------------------------------
/scripts/fid_eval.sh:
--------------------------------------------------------------------------------
1 |
2 | ##################################################################
3 | # For CIFAR model evaluation
4 | ##################################################################
5 |
6 | EXP_PATH="./model_zoo/pid_cifar"
7 |
8 | mpirun -np 1 python ./scripts/fid_evaluation.py \
9 | --training_mode one_shot_pinn_edm_edm_one_shot \
10 | --fid_dataset cifar10 \
11 | --exp_dir $EXP_PATH\
12 | --batch_size 125 \
13 | --sigma_max 80 \
14 | --sigma_min 0.002 \
15 | --s_churn 0 \
16 | --steps 35 \
17 | --sampler oneshot \
18 | --attention_resolutions "2" \
19 | --class_cond False \
20 | --dropout 0.0 \
21 | --image_size 32 \
22 | --num_channels 128 \
23 | --num_res_blocks 4 \
24 | --num_samples 50000 \
25 | --resblock_updown True \
26 | --use_fp16 False \
27 | --use_scale_shift_norm True \
28 | --weight_schedule uniform \
29 | --seed 0
30 |
31 | ##################################################################
32 |
33 |
34 | ##################################################################
35 | # For ImageNet model evaluation
36 | ##################################################################
37 |
38 | # EXP_PATH="./experiment/pid_imagenet"
39 |
40 | # mpirun -np 1 python ./scripts/fid_evaluation.py \
41 | # --training_mode one_shot_pinn_edm_edm_one_shot \
42 | # --fid_dataset imagenet \
43 | # --exp_dir $EXP_PATH\
44 | # --batch_size 250 \
45 | # --sigma_max 80 \
46 | # --sigma_min 0.002 \
47 | # --s_churn 0 \
48 | # --sampler oneshot \
49 | # --attention_resolutions 32,16,8 \
50 | # --class_cond True \
51 | # --dropout 0.0 \
52 | # --image_size 64 \
53 | # --num_channels 192 \
54 | # --num_head_channels 64 \
55 | # --num_res_blocks 3 \
56 | # --num_samples 50000 \
57 | # --resblock_updown True \
58 | # --use_fp16 True \
59 | # --use_scale_shift_norm True \
60 | # --weight_schedule uniform
61 |
62 | ##################################################################
63 |
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/scripts/distill_pid_diffusion.sh:
--------------------------------------------------------------------------------
1 | #########################################################################
2 | # PID on CIFAR10
3 | #########################################################################
4 |
5 |
6 | OPENAI_LOGDIR=./experiment/pid_cifar10 mpirun -np 8 python ./scripts/cm_train.py \
7 | --training_mode one_shot_pinn_edm_edm \
8 | --target_ema_mode fixed \
9 | --start_ema 0.5 \
10 | --scale_mode fixed \
11 | --start_scales 250 \
12 | --total_training_steps 800000 \
13 | --loss_norm lpips \
14 | --lr_anneal_steps 0 \
15 | --teacher_model_path ./model_zoo/edm-cifar10-32x32-uncond-vp.ckpt \
16 | --attention_resolutions "2" \
17 | --class_cond False \
18 | --use_scale_shift_norm True \
19 | --dropout 0.0 \
20 | --teacher_dropout 0.0 \
21 | --ema_rate 0.999,0.9999,0.99995 \
22 | --global_batch_size 512 \
23 | --microbatch -1 \
24 | --image_size 32 \
25 | --lr 0.0002 \
26 | --num_channels 128 \
27 | --num_res_blocks 4 \
28 | --resblock_updown True \
29 | --schedule_sampler uniform \
30 | --use_fp16 False \
31 | --weight_decay 0.0 \
32 | --weight_schedule uniform \
33 | --optimizer radam
34 |
35 | #########################################################################
36 |
37 |
38 | #########################################################################
39 | # PID on ImageNet 64x64
40 | #########################################################################
41 |
42 | # OPENAI_LOGDIR=./experiment/pid_imagenet mpirun -np 8 python ./scripts/cm_train.py \
43 | # --training_mode one_shot_pinn_edm_edm \
44 | # --target_ema_mode fixed \
45 | # --start_ema 0.5 \
46 | # --scale_mode fixed \
47 | # --start_scales 250 \
48 | # --total_training_steps 400000 \
49 | # --loss_norm lpips \
50 | # --lr_anneal_steps 0 \
51 | # --teacher_model_path ./model_zoo/edm-imagenet-64x64-cond-adm.ckpt \
52 | # --attention_resolutions "2" \
53 | # --class_cond True \
54 | # --use_scale_shift_norm True \
55 | # --dropout 0.0 \
56 | # --teacher_dropout 0.0 \
57 | # --ema_rate 0.999,0.9999,0.99995 \
58 | # --global_batch_size 2048 \
59 | # --microbatch 32 \
60 | # --image_size 64 \
61 | # --lr 0.0001 \
62 | # --num_channels 192 \
63 | # --num_res_blocks 3 \
64 | # --resblock_updown True \
65 | # --schedule_sampler uniform \
66 | # --use_fp16 True \
67 | # --weight_decay 0.0 \
68 | # --weight_schedule uniform \
69 | # --optimizer radam
70 |
71 | #########################################################################
72 |
73 |
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/cm/losses.py:
--------------------------------------------------------------------------------
1 | """
2 | Helpers for various likelihood-based losses. These are ported from the original
3 | Ho et al. diffusion models codebase:
4 | https://github.com/hojonathanho/diffusion/blob/1e0dceb3b3495bbe19116a5e1b3596cd0706c543/diffusion_tf/utils.py
5 | """
6 |
7 | import numpy as np
8 |
9 | import torch as th
10 |
11 |
12 | def normal_kl(mean1, logvar1, mean2, logvar2):
13 | """
14 | Compute the KL divergence between two gaussians.
15 |
16 | Shapes are automatically broadcasted, so batches can be compared to
17 | scalars, among other use cases.
18 | """
19 | tensor = None
20 | for obj in (mean1, logvar1, mean2, logvar2):
21 | if isinstance(obj, th.Tensor):
22 | tensor = obj
23 | break
24 | assert tensor is not None, "at least one argument must be a Tensor"
25 |
26 | # Force variances to be Tensors. Broadcasting helps convert scalars to
27 | # Tensors, but it does not work for th.exp().
28 | logvar1, logvar2 = [
29 | x if isinstance(x, th.Tensor) else th.tensor(x).to(tensor)
30 | for x in (logvar1, logvar2)
31 | ]
32 |
33 | return 0.5 * (
34 | -1.0
35 | + logvar2
36 | - logvar1
37 | + th.exp(logvar1 - logvar2)
38 | + ((mean1 - mean2) ** 2) * th.exp(-logvar2)
39 | )
40 |
41 |
42 | def approx_standard_normal_cdf(x):
43 | """
44 | A fast approximation of the cumulative distribution function of the
45 | standard normal.
46 | """
47 | return 0.5 * (1.0 + th.tanh(np.sqrt(2.0 / np.pi) * (x + 0.044715 * th.pow(x, 3))))
48 |
49 |
50 | def discretized_gaussian_log_likelihood(x, *, means, log_scales):
51 | """
52 | Compute the log-likelihood of a Gaussian distribution discretizing to a
53 | given image.
54 |
55 | :param x: the target images. It is assumed that this was uint8 values,
56 | rescaled to the range [-1, 1].
57 | :param means: the Gaussian mean Tensor.
58 | :param log_scales: the Gaussian log stddev Tensor.
59 | :return: a tensor like x of log probabilities (in nats).
60 | """
61 | assert x.shape == means.shape == log_scales.shape
62 | centered_x = x - means
63 | inv_stdv = th.exp(-log_scales)
64 | plus_in = inv_stdv * (centered_x + 1.0 / 255.0)
65 | cdf_plus = approx_standard_normal_cdf(plus_in)
66 | min_in = inv_stdv * (centered_x - 1.0 / 255.0)
67 | cdf_min = approx_standard_normal_cdf(min_in)
68 | log_cdf_plus = th.log(cdf_plus.clamp(min=1e-12))
69 | log_one_minus_cdf_min = th.log((1.0 - cdf_min).clamp(min=1e-12))
70 | cdf_delta = cdf_plus - cdf_min
71 | log_probs = th.where(
72 | x < -0.999,
73 | log_cdf_plus,
74 | th.where(x > 0.999, log_one_minus_cdf_min, th.log(cdf_delta.clamp(min=1e-12))),
75 | )
76 | assert log_probs.shape == x.shape
77 | return log_probs
78 |
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/cm/dist_util.py:
--------------------------------------------------------------------------------
1 | """
2 | Helpers for distributed training.
3 | """
4 |
5 | import io
6 | import os
7 | import socket
8 |
9 | import blobfile as bf
10 | from mpi4py import MPI
11 | import torch as th
12 | import torch.distributed as dist
13 |
14 | # Change this to reflect your cluster layout.
15 | # The GPU for a given rank is (rank % GPUS_PER_NODE).
16 | GPUS_PER_NODE = 8
17 |
18 | SETUP_RETRY_COUNT = 3
19 |
20 |
21 | def setup_dist():
22 | """
23 | Setup a distributed process group.
24 | """
25 | if dist.is_initialized():
26 | return
27 |
28 | os.environ["CUDA_VISIBLE_DEVICES"] = f"{int(MPI.COMM_WORLD.Get_rank() % GPUS_PER_NODE)},"
29 |
30 |
31 | comm = MPI.COMM_WORLD
32 | backend = "gloo" if not th.cuda.is_available() else "nccl"
33 |
34 | if backend == "gloo":
35 | hostname = "localhost"
36 | else:
37 | hostname = socket.gethostbyname(socket.getfqdn())
38 | os.environ["MASTER_ADDR"] = comm.bcast(hostname, root=0)
39 | os.environ["RANK"] = str(comm.rank)
40 | os.environ["WORLD_SIZE"] = str(comm.size)
41 |
42 | port = comm.bcast(_find_free_port(), root=0)
43 | os.environ["MASTER_PORT"] = str(port)
44 | dist.init_process_group(backend=backend, init_method="env://")
45 |
46 |
47 |
48 | def dev():
49 | """
50 | Get the device to use for torch.distributed.
51 | """
52 | if th.cuda.is_available():
53 | return th.device("cuda")
54 | return th.device("cpu")
55 |
56 |
57 | def load_state_dict(path, **kwargs):
58 | """
59 | Load a PyTorch file without redundant fetches across MPI ranks.
60 | """
61 | chunk_size = 2**30 # MPI has a relatively small size limit
62 | with bf.BlobFile(path, "rb") as f:
63 | data = f.read()
64 | # if MPI.COMM_WORLD.Get_rank() == 0:
65 | # with bf.BlobFile(path, "rb") as f:
66 | # data = f.read()
67 | # num_chunks = len(data) // chunk_size
68 | # if len(data) % chunk_size:
69 | # num_chunks += 1
70 | # MPI.COMM_WORLD.bcast(num_chunks)
71 | # for i in range(0, len(data), chunk_size):
72 | # MPI.COMM_WORLD.bcast(data[i : i + chunk_size])
73 | # else:
74 | # num_chunks = MPI.COMM_WORLD.bcast(None)
75 | # data = bytes()
76 | # for _ in range(num_chunks):
77 | # data += MPI.COMM_WORLD.bcast(None)
78 |
79 | return th.load(io.BytesIO(data), **kwargs)
80 |
81 |
82 | def sync_params(params):
83 | """
84 | Synchronize a sequence of Tensors across ranks from rank 0.
85 | """
86 | for p in params:
87 | with th.no_grad():
88 | dist.broadcast(p, 0)
89 |
90 |
91 | def _find_free_port():
92 | try:
93 | s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
94 | s.bind(("", 0))
95 | s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
96 | return s.getsockname()[1]
97 | finally:
98 | s.close()
99 |
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/scripts/image_sampling.sh:
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1 | #########################################################################
2 | # Image generation for ImageNet edmedm model
3 | #########################################################################
4 |
5 | # OPENAI_LOGDIR=./experiment/image_sampling/ImageNetEDM mpirun -np 1 python ./scripts/image_sample.py \
6 | # --training_mode one_shot_pinn_edm_edm_teacher \
7 | # --batch_size 128 \
8 | # --sigma_max 80 \
9 | # --sigma_min 0.002 \
10 | # --s_churn 0 \
11 | # --steps 79 \
12 | # --sampler heun_deter \
13 | # --model_path ./model_zoo/edm-imagenet-64x64-cond-adm.ckpt \
14 | # --attention_resolutions 32,16,8 \
15 | # --class_cond True \
16 | # --dropout 0.1 \
17 | # --image_size 64 \
18 | # --num_channels 192 \
19 | # --num_head_channels 64 \
20 | # --num_res_blocks 3 \
21 | # --num_samples 128 \
22 | # --resblock_updown True \
23 | # --use_fp16 False \
24 | # --use_scale_shift_norm True \
25 | # --weight_schedule uniform
26 | #########################################################################
27 |
28 | #########################################################################
29 | # Image generation for ImageNet oneshot model
30 | #########################################################################
31 |
32 | # OPENAI_LOGDIR=./experiment/image_sampling/ImageNetPID mpirun -np 1 python ./scripts/image_sample.py \
33 | # --training_mode one_shot_pinn_edm_edm_one_shot \
34 | # --batch_size 128 \
35 | # --sigma_max 80 \
36 | # --sigma_min 0.002 \
37 | # --s_churn 0 \
38 | # --steps 79 \
39 | # --sampler oneshot \
40 | # --model_path ./model_zoo/pid_imagenet64.ckpt \
41 | # --attention_resolutions 32,16,8 \
42 | # --class_cond True \
43 | # --dropout 0.1 \
44 | # --image_size 64 \
45 | # --num_channels 192 \
46 | # --num_head_channels 64 \
47 | # --num_res_blocks 3 \
48 | # --num_samples 128 \
49 | # --resblock_updown True \
50 | # --use_fp16 False \
51 | # --use_scale_shift_norm True \
52 | # --weight_schedule uniform
53 |
54 | #########################################################################
55 |
56 |
57 | #########################################################################
58 | # Image generation for cifar edmedm model
59 | #########################################################################
60 |
61 | OPENAI_LOGDIR=./experiment/image_sampling/CIFAREDM mpirun -np 1 python ./scripts/image_sample.py \
62 | --training_mode one_shot_pinn_edm_edm_teacher \
63 | --batch_size 128 \
64 | --sigma_max 80 \
65 | --sigma_min 0.002 \
66 | --s_churn 0 \
67 | --steps 35 \
68 | --sampler heun_deter \
69 | --model_path ./model_zoo/edm-cifar10-32x32-uncond-vp.ckpt \
70 | --attention_resolutions "2" \
71 | --class_cond False \
72 | --dropout 0.0 \
73 | --image_size 32 \
74 | --num_channels 192 \
75 | --num_channels 128 \
76 | --num_res_blocks 4 \
77 | --num_samples 128 \
78 | --resblock_updown True \
79 | --use_fp16 False \
80 | --use_scale_shift_norm True \
81 | --weight_schedule uniform
82 | #########################################################################
83 |
84 |
85 | #########################################################################
86 | # Image generation for cifar oneshot model
87 | #########################################################################
88 |
89 | # OPENAI_LOGDIR=./experiment/image_sampling/CIFARPID mpirun -np 1 python ./scripts/image_sample.py \
90 | # --training_mode one_shot_pinn_edm_edm_one_shot \
91 | # --batch_size 128 \
92 | # --sigma_max 80 \
93 | # --sigma_min 0.002 \
94 | # --s_churn 0 \
95 | # --steps 35 \
96 | # --sampler oneshot \
97 | # --model_path ./model_zoo/pid_cifar.pt \
98 | # --attention_resolutions "2" \
99 | # --class_cond False \
100 | # --dropout 0.0 \
101 | # --image_size 32 \
102 | # --num_channels 192 \
103 | # --num_channels 128 \
104 | # --num_res_blocks 4 \
105 | # --num_samples 128 \
106 | # --resblock_updown True \
107 | # --use_fp16 False \
108 | # --use_scale_shift_norm True \
109 | # --weight_schedule uniform
110 | #########################################################################
111 |
112 |
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/scripts/image_sample.py:
--------------------------------------------------------------------------------
1 | """
2 | Generate a large batch of image samples from a model and save them as a large
3 | numpy array. This can be used to produce samples for FID evaluation.
4 | """
5 |
6 | import argparse
7 | import os
8 |
9 | import numpy as np
10 | import torch as th
11 | import torch.distributed as dist
12 |
13 | from cm import dist_util, logger
14 | from cm.script_util import (
15 | NUM_CLASSES,
16 | model_and_diffusion_defaults,
17 | create_model_and_diffusion,
18 | add_dict_to_argparser,
19 | args_to_dict,
20 | create_one_shot_edmedm_model_and_diffusion,
21 | )
22 | from cm.random_util import get_generator
23 | from cm.karras_diffusion import karras_sample
24 | import copy
25 | import torchvision
26 |
27 | def main():
28 | args = create_argparser().parse_args()
29 |
30 | dist_util.setup_dist()
31 | logger.configure()
32 |
33 | logger.log("creating model and diffusion...")
34 | model_and_diffusion_kwargs = args_to_dict(args, model_and_diffusion_defaults().keys())
35 |
36 | if "one_shot_pinn_edm_edm_teacher" == args.training_mode:
37 | model, diffusion = create_one_shot_edmedm_model_and_diffusion(teacher_precond=True,
38 | **args_to_dict(args, model_and_diffusion_defaults().keys()),
39 | )
40 | load_weights = dist_util.load_state_dict(args.model_path, map_location="cpu")
41 | new_state_dict = {}
42 | for k, v in load_weights.items():
43 | if "map_augment" in k:
44 | continue
45 | new_key = k.replace("model.", "")
46 | new_state_dict[new_key] = v
47 |
48 | model.load_state_dict(new_state_dict)
49 | elif "one_shot_pinn_edm_edm_one_shot" == args.training_mode:
50 | model, diffusion = create_one_shot_edmedm_model_and_diffusion(teacher_precond=False,
51 | **args_to_dict(args, model_and_diffusion_defaults().keys()),
52 | )
53 | load_weights = dist_util.load_state_dict(args.model_path, map_location="cpu")
54 | new_state_dict = {}
55 | for k, v in load_weights.items():
56 | if "map_augment" in k:
57 | continue
58 | new_key = k.replace("model.", "")
59 | new_state_dict[new_key] = v
60 |
61 | model.load_state_dict(new_state_dict)
62 |
63 |
64 | model.to(dist_util.dev())
65 | if args.use_fp16:
66 | model.convert_to_fp16()
67 | model.eval()
68 |
69 | logger.log("sampling...")
70 | if args.sampler == "multistep":
71 | assert len(args.ts) > 0
72 | ts = tuple(int(x) for x in args.ts.split(","))
73 | else:
74 | ts = None
75 |
76 | all_images = []
77 | all_labels = []
78 | generator = get_generator(args.generator, args.num_samples, args.seed)
79 |
80 | while len(all_images) * args.batch_size < args.num_samples:
81 | model_kwargs = {}
82 | if args.class_cond:
83 | classes = th.randint(
84 | low=0, high=NUM_CLASSES, size=(args.batch_size,), device=dist_util.dev()
85 | )
86 | model_kwargs["y"] = classes
87 |
88 | sample_ori = karras_sample(
89 | diffusion,
90 | model,
91 | (args.batch_size, 3, args.image_size, args.image_size),
92 | steps=args.steps,
93 | model_kwargs=model_kwargs,
94 | device=dist_util.dev(),
95 | clip_denoised=args.clip_denoised,
96 | sampler=args.sampler,
97 | sigma_min=args.sigma_min,
98 | sigma_max=args.sigma_max,
99 | s_churn=args.s_churn,
100 | s_tmin=args.s_tmin,
101 | s_tmax=args.s_tmax,
102 | s_noise=args.s_noise,
103 | generator=generator,
104 | ts=ts,
105 | )
106 | sample = ((sample_ori + 1) * 127.5).clamp(0, 255).to(th.uint8)
107 | sample = sample.permute(0, 2, 3, 1)
108 | sample = sample.contiguous()
109 |
110 | gathered_samples = [th.zeros_like(sample) for _ in range(dist.get_world_size())]
111 | dist.all_gather(gathered_samples, sample) # gather not supported with NCCL
112 | all_images.extend([sample.cpu().numpy() for sample in gathered_samples])
113 | if args.class_cond:
114 | gathered_labels = [
115 | th.zeros_like(classes) for _ in range(dist.get_world_size())
116 | ]
117 | dist.all_gather(gathered_labels, classes)
118 | all_labels.extend([labels.cpu().numpy() for labels in gathered_labels])
119 | logger.log(f"created {len(all_images) * args.batch_size} samples")
120 |
121 | if len(all_images) <= args.batch_size and dist.get_rank() == 0:
122 | torchvision.utils.save_image((sample_ori + 1.)/2., os.path.join(logger.get_dir(), f"samples_first_batch.png"))
123 |
124 | arr = np.concatenate(all_images, axis=0)
125 | arr = arr[: args.num_samples]
126 | if args.class_cond:
127 | label_arr = np.concatenate(all_labels, axis=0)
128 | label_arr = label_arr[: args.num_samples]
129 | if dist.get_rank() == 0:
130 | shape_str = "x".join([str(x) for x in arr.shape])
131 | out_path = os.path.join(logger.get_dir(), f"samples_{shape_str}.npz")
132 | logger.log(f"saving to {out_path}")
133 |
134 | if args.class_cond:
135 | np.savez(out_path, arr, label_arr)
136 | else:
137 | np.savez(out_path, arr)
138 |
139 | dist.barrier()
140 | logger.log("sampling complete")
141 |
142 |
143 | def create_argparser():
144 | defaults = dict(
145 | training_mode="edm",
146 | generator="determ",
147 | clip_denoised=True,
148 | num_samples=10000,
149 | batch_size=16,
150 | sampler="heun",
151 | s_churn=0.0,
152 | s_tmin=0.0,
153 | s_tmax=float("inf"),
154 | s_noise=1.0,
155 | steps=40,
156 | model_path="",
157 | seed=42,
158 | ts="",
159 | )
160 | defaults.update(model_and_diffusion_defaults())
161 | parser = argparse.ArgumentParser()
162 | add_dict_to_argparser(parser, defaults)
163 | return parser
164 |
165 |
166 | if __name__ == "__main__":
167 | main()
168 |
--------------------------------------------------------------------------------
/cm/nn.py:
--------------------------------------------------------------------------------
1 | """
2 | Various utilities for neural networks.
3 | """
4 |
5 | import math
6 |
7 | import torch as th
8 | import torch.nn as nn
9 | import numpy as np
10 | import torch.nn.functional as F
11 |
12 |
13 | # PyTorch 1.7 has SiLU, but we support PyTorch 1.5.
14 | class SiLU(nn.Module):
15 | def forward(self, x):
16 | return x * th.sigmoid(x)
17 |
18 |
19 | class GroupNorm32(nn.GroupNorm):
20 | def forward(self, x):
21 | return super().forward(x.float()).type(x.dtype)
22 |
23 |
24 | def conv_nd(dims, *args, **kwargs):
25 | """
26 | Create a 1D, 2D, or 3D convolution module.
27 | """
28 | if dims == 1:
29 | return nn.Conv1d(*args, **kwargs)
30 | elif dims == 2:
31 | return nn.Conv2d(*args, **kwargs)
32 | elif dims == 3:
33 | return nn.Conv3d(*args, **kwargs)
34 | raise ValueError(f"unsupported dimensions: {dims}")
35 |
36 |
37 | def linear(*args, **kwargs):
38 | """
39 | Create a linear module.
40 | """
41 | return nn.Linear(*args, **kwargs)
42 |
43 |
44 | def avg_pool_nd(dims, *args, **kwargs):
45 | """
46 | Create a 1D, 2D, or 3D average pooling module.
47 | """
48 | if dims == 1:
49 | return nn.AvgPool1d(*args, **kwargs)
50 | elif dims == 2:
51 | return nn.AvgPool2d(*args, **kwargs)
52 | elif dims == 3:
53 | return nn.AvgPool3d(*args, **kwargs)
54 | raise ValueError(f"unsupported dimensions: {dims}")
55 |
56 |
57 | def update_ema(target_params, source_params, rate=0.99):
58 | """
59 | Update target parameters to be closer to those of source parameters using
60 | an exponential moving average.
61 |
62 | :param target_params: the target parameter sequence.
63 | :param source_params: the source parameter sequence.
64 | :param rate: the EMA rate (closer to 1 means slower).
65 | """
66 | for targ, src in zip(target_params, source_params):
67 | targ.detach().mul_(rate).add_(src, alpha=1 - rate)
68 |
69 |
70 | def zero_module(module):
71 | """
72 | Zero out the parameters of a module and return it.
73 | """
74 | for p in module.parameters():
75 | p.detach().zero_()
76 | return module
77 |
78 |
79 | def scale_module(module, scale):
80 | """
81 | Scale the parameters of a module and return it.
82 | """
83 | for p in module.parameters():
84 | p.detach().mul_(scale)
85 | return module
86 |
87 |
88 | def mean_flat(tensor):
89 | """
90 | Take the mean over all non-batch dimensions.
91 | """
92 | return tensor.mean(dim=list(range(1, len(tensor.shape))))
93 |
94 |
95 | def append_dims(x, target_dims):
96 | """Appends dimensions to the end of a tensor until it has target_dims dimensions."""
97 | dims_to_append = target_dims - x.ndim
98 | if dims_to_append < 0:
99 | raise ValueError(
100 | f"input has {x.ndim} dims but target_dims is {target_dims}, which is less"
101 | )
102 | return x[(...,) + (None,) * dims_to_append]
103 |
104 |
105 | def append_zero(x):
106 | return th.cat([x, x.new_zeros([1])])
107 |
108 |
109 | def normalization(channels):
110 | """
111 | Make a standard normalization layer.
112 |
113 | :param channels: number of input channels.
114 | :return: an nn.Module for normalization.
115 | """
116 | return GroupNorm32(32, channels)
117 |
118 |
119 | def timestep_embedding(timesteps, dim, max_period=10000):
120 | """
121 | Create sinusoidal timestep embeddings.
122 |
123 | :param timesteps: a 1-D Tensor of N indices, one per batch element.
124 | These may be fractional.
125 | :param dim: the dimension of the output.
126 | :param max_period: controls the minimum frequency of the embeddings.
127 | :return: an [N x dim] Tensor of positional embeddings.
128 | """
129 | half = dim // 2
130 | freqs = th.exp(
131 | -math.log(max_period) * th.arange(start=0, end=half, dtype=th.float32) / half
132 | ).to(device=timesteps.device)
133 | args = timesteps[:, None].float() * freqs[None]
134 | embedding = th.cat([th.cos(args), th.sin(args)], dim=-1)
135 | if dim % 2:
136 | embedding = th.cat([embedding, th.zeros_like(embedding[:, :1])], dim=-1)
137 | return embedding
138 |
139 |
140 | def checkpoint(func, inputs, params, flag):
141 | """
142 | Evaluate a function without caching intermediate activations, allowing for
143 | reduced memory at the expense of extra compute in the backward pass.
144 |
145 | :param func: the function to evaluate.
146 | :param inputs: the argument sequence to pass to `func`.
147 | :param params: a sequence of parameters `func` depends on but does not
148 | explicitly take as arguments.
149 | :param flag: if False, disable gradient checkpointing.
150 | """
151 | if flag:
152 | args = tuple(inputs) + tuple(params)
153 | return CheckpointFunction.apply(func, len(inputs), *args)
154 | else:
155 | return func(*inputs)
156 |
157 |
158 | class CheckpointFunction(th.autograd.Function):
159 | @staticmethod
160 | def forward(ctx, run_function, length, *args):
161 | ctx.run_function = run_function
162 | ctx.input_tensors = list(args[:length])
163 | ctx.input_params = list(args[length:])
164 | with th.no_grad():
165 | output_tensors = ctx.run_function(*ctx.input_tensors)
166 | return output_tensors
167 |
168 | @staticmethod
169 | def backward(ctx, *output_grads):
170 | ctx.input_tensors = [x.detach().requires_grad_(True) for x in ctx.input_tensors]
171 | with th.enable_grad():
172 | # Fixes a bug where the first op in run_function modifies the
173 | # Tensor storage in place, which is not allowed for detach()'d
174 | # Tensors.
175 | shallow_copies = [x.view_as(x) for x in ctx.input_tensors]
176 | output_tensors = ctx.run_function(*shallow_copies)
177 | input_grads = th.autograd.grad(
178 | output_tensors,
179 | ctx.input_tensors + ctx.input_params,
180 | output_grads,
181 | allow_unused=True,
182 | )
183 | del ctx.input_tensors
184 | del ctx.input_params
185 | del output_tensors
186 | return (None, None) + input_grads
187 |
--------------------------------------------------------------------------------
/cm/image_datasets.py:
--------------------------------------------------------------------------------
1 | import math
2 | import random
3 |
4 | from PIL import Image
5 | import blobfile as bf
6 | from mpi4py import MPI
7 | import numpy as np
8 | from torch.utils.data import DataLoader, Dataset
9 |
10 |
11 | def load_data(
12 | *,
13 | data_dir,
14 | batch_size,
15 | image_size,
16 | class_cond=False,
17 | deterministic=False,
18 | random_crop=False,
19 | random_flip=True,
20 | ):
21 | """
22 | For a dataset, create a generator over (images, kwargs) pairs.
23 |
24 | Each images is an NCHW float tensor, and the kwargs dict contains zero or
25 | more keys, each of which map to a batched Tensor of their own.
26 | The kwargs dict can be used for class labels, in which case the key is "y"
27 | and the values are integer tensors of class labels.
28 |
29 | :param data_dir: a dataset directory.
30 | :param batch_size: the batch size of each returned pair.
31 | :param image_size: the size to which images are resized.
32 | :param class_cond: if True, include a "y" key in returned dicts for class
33 | label. If classes are not available and this is true, an
34 | exception will be raised.
35 | :param deterministic: if True, yield results in a deterministic order.
36 | :param random_crop: if True, randomly crop the images for augmentation.
37 | :param random_flip: if True, randomly flip the images for augmentation.
38 | """
39 | if not data_dir:
40 | raise ValueError("unspecified data directory")
41 | all_files = _list_image_files_recursively(data_dir)
42 | classes = None
43 | if class_cond:
44 | # Assume classes are the first part of the filename,
45 | # before an underscore.
46 | class_names = [bf.basename(path).split("_")[0] for path in all_files]
47 | sorted_classes = {x: i for i, x in enumerate(sorted(set(class_names)))}
48 | classes = [sorted_classes[x] for x in class_names]
49 | dataset = ImageDataset(
50 | image_size,
51 | all_files,
52 | classes=classes,
53 | shard=MPI.COMM_WORLD.Get_rank(),
54 | num_shards=MPI.COMM_WORLD.Get_size(),
55 | random_crop=random_crop,
56 | random_flip=random_flip,
57 | )
58 | if deterministic:
59 | loader = DataLoader(
60 | dataset, batch_size=batch_size, shuffle=False, num_workers=4, drop_last=True
61 | )
62 | else:
63 | loader = DataLoader(
64 | dataset, batch_size=batch_size, shuffle=True, num_workers=4, drop_last=True
65 | )
66 | while True:
67 | yield from loader
68 |
69 |
70 | def _list_image_files_recursively(data_dir):
71 | results = []
72 | for entry in sorted(bf.listdir(data_dir)):
73 | full_path = bf.join(data_dir, entry)
74 | ext = entry.split(".")[-1]
75 | if "." in entry and ext.lower() in ["jpg", "jpeg", "png", "gif"]:
76 | results.append(full_path)
77 | elif bf.isdir(full_path):
78 | results.extend(_list_image_files_recursively(full_path))
79 | return results
80 |
81 |
82 | class ImageDataset(Dataset):
83 | def __init__(
84 | self,
85 | resolution,
86 | image_paths,
87 | classes=None,
88 | shard=0,
89 | num_shards=1,
90 | random_crop=False,
91 | random_flip=True,
92 | ):
93 | super().__init__()
94 | self.resolution = resolution
95 | self.local_images = image_paths[shard:][::num_shards]
96 | self.local_classes = None if classes is None else classes[shard:][::num_shards]
97 | self.random_crop = random_crop
98 | self.random_flip = random_flip
99 |
100 | def __len__(self):
101 | return len(self.local_images)
102 |
103 | def __getitem__(self, idx):
104 | path = self.local_images[idx]
105 | with bf.BlobFile(path, "rb") as f:
106 | pil_image = Image.open(f)
107 | pil_image.load()
108 | pil_image = pil_image.convert("RGB")
109 |
110 | if self.random_crop:
111 | arr = random_crop_arr(pil_image, self.resolution)
112 | else:
113 | arr = center_crop_arr(pil_image, self.resolution)
114 |
115 | if self.random_flip and random.random() < 0.5:
116 | arr = arr[:, ::-1]
117 |
118 | arr = arr.astype(np.float32) / 127.5 - 1
119 |
120 | out_dict = {}
121 | if self.local_classes is not None:
122 | out_dict["y"] = np.array(self.local_classes[idx], dtype=np.int64)
123 | return np.transpose(arr, [2, 0, 1]), out_dict
124 |
125 |
126 | def center_crop_arr(pil_image, image_size):
127 | # We are not on a new enough PIL to support the `reducing_gap`
128 | # argument, which uses BOX downsampling at powers of two first.
129 | # Thus, we do it by hand to improve downsample quality.
130 | while min(*pil_image.size) >= 2 * image_size:
131 | pil_image = pil_image.resize(
132 | tuple(x // 2 for x in pil_image.size), resample=Image.BOX
133 | )
134 |
135 | scale = image_size / min(*pil_image.size)
136 | pil_image = pil_image.resize(
137 | tuple(round(x * scale) for x in pil_image.size), resample=Image.BICUBIC
138 | )
139 |
140 | arr = np.array(pil_image)
141 | crop_y = (arr.shape[0] - image_size) // 2
142 | crop_x = (arr.shape[1] - image_size) // 2
143 | return arr[crop_y : crop_y + image_size, crop_x : crop_x + image_size]
144 |
145 |
146 | def random_crop_arr(pil_image, image_size, min_crop_frac=0.8, max_crop_frac=1.0):
147 | min_smaller_dim_size = math.ceil(image_size / max_crop_frac)
148 | max_smaller_dim_size = math.ceil(image_size / min_crop_frac)
149 | smaller_dim_size = random.randrange(min_smaller_dim_size, max_smaller_dim_size + 1)
150 |
151 | # We are not on a new enough PIL to support the `reducing_gap`
152 | # argument, which uses BOX downsampling at powers of two first.
153 | # Thus, we do it by hand to improve downsample quality.
154 | while min(*pil_image.size) >= 2 * smaller_dim_size:
155 | pil_image = pil_image.resize(
156 | tuple(x // 2 for x in pil_image.size), resample=Image.BOX
157 | )
158 |
159 | scale = smaller_dim_size / min(*pil_image.size)
160 | pil_image = pil_image.resize(
161 | tuple(round(x * scale) for x in pil_image.size), resample=Image.BICUBIC
162 | )
163 |
164 | arr = np.array(pil_image)
165 | crop_y = random.randrange(arr.shape[0] - image_size + 1)
166 | crop_x = random.randrange(arr.shape[1] - image_size + 1)
167 | return arr[crop_y : crop_y + image_size, crop_x : crop_x + image_size]
168 |
--------------------------------------------------------------------------------
/cm/random_util.py:
--------------------------------------------------------------------------------
1 | import torch as th
2 | import torch.distributed as dist
3 | from . import dist_util
4 |
5 |
6 | def get_generator(generator, num_samples=0, seed=0):
7 | if generator == "dummy":
8 | return DummyGenerator()
9 | elif generator == "determ":
10 | return DeterministicGenerator(num_samples, seed)
11 | elif generator == "determ-indiv":
12 | return DeterministicIndividualGenerator(num_samples, seed)
13 | else:
14 | raise NotImplementedError
15 |
16 |
17 | class DummyGenerator:
18 | def randn(self, *args, **kwargs):
19 | return th.randn(*args, **kwargs)
20 |
21 | def randint(self, *args, **kwargs):
22 | return th.randint(*args, **kwargs)
23 |
24 | def randn_like(self, *args, **kwargs):
25 | return th.randn_like(*args, **kwargs)
26 |
27 |
28 | class DeterministicGenerator:
29 | """
30 | RNG to deterministically sample num_samples samples that does not depend on batch_size or mpi_machines
31 | Uses a single rng and samples num_samples sized randomness and subsamples the current indices
32 | """
33 |
34 | def __init__(self, num_samples, seed=0):
35 | if dist.is_initialized():
36 | self.rank = dist.get_rank()
37 | self.world_size = dist.get_world_size()
38 | else:
39 | print("Warning: Distributed not initialised, using single rank")
40 | self.rank = 0
41 | self.world_size = 1
42 | self.num_samples = num_samples
43 | self.done_samples = 0
44 | self.seed = seed
45 | self.rng_cpu = th.Generator()
46 | if th.cuda.is_available():
47 | self.rng_cuda = th.Generator(dist_util.dev())
48 | self.set_seed(seed)
49 |
50 | def get_global_size_and_indices(self, size):
51 | global_size = (self.num_samples, *size[1:])
52 | indices = th.arange(
53 | self.done_samples + self.rank,
54 | self.done_samples + self.world_size * int(size[0]),
55 | self.world_size,
56 | )
57 | indices = th.clamp(indices, 0, self.num_samples - 1)
58 | assert (
59 | len(indices) == size[0]
60 | ), f"rank={self.rank}, ws={self.world_size}, l={len(indices)}, bs={size[0]}"
61 | return global_size, indices
62 |
63 | def get_generator(self, device):
64 | return self.rng_cpu if th.device(device).type == "cpu" else self.rng_cuda
65 |
66 | def randn(self, *size, dtype=th.float, device="cpu"):
67 | global_size, indices = self.get_global_size_and_indices(size)
68 | generator = self.get_generator(device)
69 | return th.randn(*global_size, generator=generator, dtype=dtype, device=device)[
70 | indices
71 | ]
72 |
73 | def randint(self, low, high, size, dtype=th.long, device="cpu"):
74 | global_size, indices = self.get_global_size_and_indices(size)
75 | generator = self.get_generator(device)
76 | return th.randint(
77 | low, high, generator=generator, size=global_size, dtype=dtype, device=device
78 | )[indices]
79 |
80 | def randn_like(self, tensor):
81 | size, dtype, device = tensor.size(), tensor.dtype, tensor.device
82 | return self.randn(*size, dtype=dtype, device=device)
83 |
84 | def set_done_samples(self, done_samples):
85 | self.done_samples = done_samples
86 | self.set_seed(self.seed)
87 |
88 | def get_seed(self):
89 | return self.seed
90 |
91 | def set_seed(self, seed):
92 | self.rng_cpu.manual_seed(seed)
93 | if th.cuda.is_available():
94 | self.rng_cuda.manual_seed(seed)
95 |
96 |
97 | class DeterministicIndividualGenerator:
98 | """
99 | RNG to deterministically sample num_samples samples that does not depend on batch_size or mpi_machines
100 | Uses a separate rng for each sample to reduce memoery usage
101 | """
102 |
103 | def __init__(self, num_samples, seed=0):
104 | if dist.is_initialized():
105 | self.rank = dist.get_rank()
106 | self.world_size = dist.get_world_size()
107 | else:
108 | print("Warning: Distributed not initialised, using single rank")
109 | self.rank = 0
110 | self.world_size = 1
111 | self.num_samples = num_samples
112 | self.done_samples = 0
113 | self.seed = seed
114 | self.rng_cpu = [th.Generator() for _ in range(num_samples)]
115 | if th.cuda.is_available():
116 | self.rng_cuda = [th.Generator(dist_util.dev()) for _ in range(num_samples)]
117 | self.set_seed(seed)
118 |
119 | def get_size_and_indices(self, size):
120 | indices = th.arange(
121 | self.done_samples + self.rank,
122 | self.done_samples + self.world_size * int(size[0]),
123 | self.world_size,
124 | )
125 | indices = th.clamp(indices, 0, self.num_samples - 1)
126 | assert (
127 | len(indices) == size[0]
128 | ), f"rank={self.rank}, ws={self.world_size}, l={len(indices)}, bs={size[0]}"
129 | return (1, *size[1:]), indices
130 |
131 | def get_generator(self, device):
132 | return self.rng_cpu if th.device(device).type == "cpu" else self.rng_cuda
133 |
134 | def randn(self, *size, dtype=th.float, device="cpu"):
135 | size, indices = self.get_size_and_indices(size)
136 | generator = self.get_generator(device)
137 | return th.cat(
138 | [
139 | th.randn(*size, generator=generator[i], dtype=dtype, device=device)
140 | for i in indices
141 | ],
142 | dim=0,
143 | )
144 |
145 | def randint(self, low, high, size, dtype=th.long, device="cpu"):
146 | size, indices = self.get_size_and_indices(size)
147 | generator = self.get_generator(device)
148 | return th.cat(
149 | [
150 | th.randint(
151 | low,
152 | high,
153 | generator=generator[i],
154 | size=size,
155 | dtype=dtype,
156 | device=device,
157 | )
158 | for i in indices
159 | ],
160 | dim=0,
161 | )
162 |
163 | def randn_like(self, tensor):
164 | size, dtype, device = tensor.size(), tensor.dtype, tensor.device
165 | return self.randn(*size, dtype=dtype, device=device)
166 |
167 | def set_done_samples(self, done_samples):
168 | self.done_samples = done_samples
169 |
170 | def get_seed(self):
171 | return self.seed
172 |
173 | def set_seed(self, seed):
174 | [
175 | rng_cpu.manual_seed(i + self.num_samples * seed)
176 | for i, rng_cpu in enumerate(self.rng_cpu)
177 | ]
178 | if th.cuda.is_available():
179 | [
180 | rng_cuda.manual_seed(i + self.num_samples * seed)
181 | for i, rng_cuda in enumerate(self.rng_cuda)
182 | ]
183 |
--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
1 | # Physics Informed Distillation for Diffusion Models
2 |
3 | Joshua Tian Jin Tee*, Kang Zhang*, Hee Suk Yoon, Dhananjaya Nagaraja Gowda, Chanwoo Kim, Chang D. Yoo (*Equal contribution)
4 |
5 | This repository is the official implementation of the paper: [Physics Informed Distillation for Diffusion Models](https://openreview.net/forum?id=rOvaUsF996), accepted by Transactions on Machine Learning Research (TMLR).
6 |
7 | Diffusion models have recently emerged as a potent tool in generative modeling. However, their inherent iterative nature often results in sluggish image generation due to the requirement for multiple model evaluations. Recent progress has unveiled the intrinsic link between diffusion models and Probability Flow Ordinary Differential Equations (ODEs), thus enabling us to conceptualize diffusion models as ODE systems. Simultaneously, Physics Informed Neural Networks (PINNs) have substantiated their effectiveness in solving intricate differential equations through implicit modeling of their solutions. Building upon these foundational insights, we introduce Physics Informed Distillation (PID), which employs a student model to represent the solution of the ODE system corresponding to the teacher diffusion model, akin to the principles employed in PINNs. Through experiments on CIFAR 10 and ImageNet 64x64, we observe that PID achieves performance comparable to recent distillation methods. Notably, it demonstrates predictable trends concerning method-specific hyperparameters and eliminates the need for synthetic dataset generation during the distillation process. Both of which contribute to its easy-to-use nature as a distillation approach for Diffusion Models.
8 |
9 |
10 |
11 |
12 |
13 |
14 | An overview of the proposed method, which involves training a model $\mathbf{x}_{\theta}(\mathbf{z}, \cdot )$ to approximate the true trajectory $\mathbf{x}(\mathbf{z}, \cdot )$.
15 |
16 |
17 |
18 | # 🔧 Environment Setup
19 |
20 | To install all packages in this codebase along with their dependencies, run
21 | ```sh
22 | conda create -n pid-diffusion python=3.9
23 | conda activate pid-diffusion
24 | conda install pytorch=1.13.1 torchvision=0.14.1 pytorch-cuda=11.6 -c pytorch -c nvidia
25 | conda install -c "nvidia/label/cuda-11.6.1" libcusolver-dev
26 | conda install mpi4py
27 | git clone https://github.com/pantheon5100/pid_diffusion.git
28 | cd pid_diffusion
29 | pip install -e .
30 | ```
31 |
32 | # ⚡ Get Started
33 |
34 | ## 1. Preparing Pretrained Checkpoints
35 | ### Teacher Models for Distillation
36 | For CIFAR10 and ImageNet 64x64 experiments, we use the teacher model from [EDM](https://github.com/NVlabs/edm). The released checkpoint is a pickle file, so we need to extract the weights first. Run the official image sampling [code](https://github.com/NVlabs/edm/blob/main/generate.py) to save the model's state dict.
37 |
38 | We provide the extracted checkpoints for direct use under the same license as the original EDM checkpoint [Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License](http://creativecommons.org/licenses/by-nc-sa/4.0/):
39 | - [EDM-CIFAR10](https://drive.google.com/file/d/1UT72TxuDcJ6F54fsBgDZDVYix1sS8vKd/view?usp=sharing)
40 | - [EDM-ImageNet64x64-EDM](https://drive.google.com/file/d/1sKFMEk48BHb7x7FJpPHsLxTGyIhgpCOm/view?usp=sharing)
41 |
42 | ### Pretrained PID Checkpoints
43 | Additionally, our distilled models for these datasets are available for direct evaluation:
44 | - [PID-CIFAR10](https://drive.google.com/file/d/1uhJnW-vbdheHIMX2NyoqW921-f9VTuYI/view?usp=drive_link)
45 | - [PID-ImageNet64x64](https://drive.google.com/file/d/1crecnZxE8BwHSp8YaEzV2jpAEH4MYUb4/view?usp=drive_link)
46 |
47 | Download the checkpoints and place them in the ./model_zoo directory.
48 |
49 | ## 2. Distillation with PID
50 | To start the distillation, use the bash scripts:
51 | ```bash
52 | bash ./scripts/distill_pid_diffusion.sh
53 | ```
54 |
55 | We use Open MPI to launch our code. Before running the experiment, configure the following in the bash file:
56 |
57 | > a. Set the environment variable `OPENAI_LOGDIR` to specify where the experiment data will be stored (e.g., `../experiment/EXP_NAME`, where `EXP_NAME` is the experiment name).
58 | >
59 | > b. Specify the number of GPUs to use (e.g., `-np 8` to use 8 GPUs).
60 | >
61 | > c. Set the total batch size across all GPUs (e.g., `--global_batch_size 512`, which will result in a batch size of `512/8=64` per GPU).
62 |
63 | ## 3. Image Sampling for EDM and PID model
64 | Use the bash script `./scripts/image_sampling.sh` to sample images from the pre-trained teacher model or the distilled model. The distilled PID model can be downloaded [here](https://drive.google.com/drive/folders/1rOmGWPyfhaVr6nfbVzJ8Xruk2ePWu1XE?usp=sharing). We provide the distilled one step model for both CIFAR and ImageNet64.
65 |
66 |
67 |
68 | ## 4. FID Evaluation
69 | To evaluate FID scores, use the provided bash script `./scripts/fid_eval.sh`, which will evaluate all checkpoints in the `EXP_PATH` folder. Download the reference statistics for the teacher model from [EDM](https://nvlabs-fi-cdn.nvidia.com/edm/fid-refs/) and place them in `./model_zoo/stats/cifar10-32x32.npz` and `./model_zoo/stats/imagenet-64x64.npz`. Run the following to download the reference statistics:
70 | ```bash
71 | mkdir ./model_zoo/stats
72 | wget https://nvlabs-fi-cdn.nvidia.com/edm/fid-refs/cifar10-32x32.npz -P ./model_zoo/stats
73 | wget https://nvlabs-fi-cdn.nvidia.com/edm/fid-refs/imagenet-64x64.npz -o ./model_zoo/stats/imagenet-64x64.npz
74 | ```
75 |
76 | To assess our pretrained [CIFAR10 model](https://drive.google.com/file/d/1uhJnW-vbdheHIMX2NyoqW921-f9VTuYI/view?usp=sharing), place it in `model_zoo/pid_cifar/pid_cifar.pt`, then execute the following for evaluation:
77 | ```bash
78 | EXP_PATH="./model_zoo/pid_cifar"
79 |
80 | mpirun -np 1 python ./scripts/fid_evaluation.py \
81 | --training_mode one_shot_pinn_edm_edm_one_shot \
82 | --fid_dataset cifar10 \
83 | --exp_dir $EXP_PATH\
84 | --batch_size 125 \
85 | --sigma_max 80 \
86 | --sigma_min 0.002 \
87 | --s_churn 0 \
88 | --steps 35 \
89 | --sampler oneshot \
90 | --attention_resolutions "2" \
91 | --class_cond False \
92 | --dropout 0.0 \
93 | --image_size 32 \
94 | --num_channels 128 \
95 | --num_res_blocks 4 \
96 | --num_samples 50000 \
97 | --resblock_updown True \
98 | --use_fp16 False \
99 | --use_scale_shift_norm True \
100 | --weight_schedule uniform \
101 | --seed 0
102 | ```
103 |
104 | # Citation
105 | ```
106 | @article{
107 | tee2024physics,
108 | title={Physics Informed Distillation for Diffusion Models},
109 | author={Joshua Tian Jin Tee and Kang Zhang and Hee Suk Yoon and Dhananjaya Nagaraja Gowda and Chanwoo Kim and Chang D. Yoo},
110 | journal={Transactions on Machine Learning Research},
111 | issn={2835-8856},
112 | year={2024},
113 | url={https://openreview.net/forum?id=rOvaUsF996},
114 | note={}
115 | }
116 | ```
117 |
118 | # Acknowledgments
119 | This repository is based on [openai/consistency_models](https://github.com/openai/consistency_models) and [EDM](https://github.com/NVlabs/edm).
120 |
121 |
--------------------------------------------------------------------------------
/scripts/cm_train.py:
--------------------------------------------------------------------------------
1 | """
2 | Train a diffusion model on images.
3 | """
4 |
5 | import argparse
6 |
7 | from cm import dist_util, logger
8 | from cm.image_datasets import load_data
9 | from cm.resample import create_named_schedule_sampler
10 | from cm.script_util import (
11 | model_and_diffusion_defaults,
12 | create_model_and_diffusion,
13 | create_one_shot_edmedm_model_and_diffusion,
14 | cm_train_defaults,
15 | args_to_dict,
16 | add_dict_to_argparser,
17 | create_ema_and_scales_fn,
18 | )
19 | from cm.train_util import ODETrainLoop
20 | import torch.distributed as dist
21 | import copy
22 | import torch
23 |
24 | def main():
25 | args = create_argparser().parse_args()
26 |
27 | dist_util.setup_dist()
28 | logger.configure()
29 |
30 | logger.log("creating model and diffusion...")
31 | ema_scale_fn = create_ema_and_scales_fn(
32 | target_ema_mode=args.target_ema_mode,
33 | start_ema=args.start_ema,
34 | scale_mode=args.scale_mode,
35 | start_scales=args.start_scales,
36 | end_scales=args.end_scales,
37 | total_steps=args.total_training_steps,
38 | distill_steps_per_iter=args.distill_steps_per_iter,
39 | )
40 |
41 | model_and_diffusion_kwargs = args_to_dict(args, model_and_diffusion_defaults().keys())
42 | if args.training_mode == "progdist":
43 | distillation = False
44 | model_and_diffusion_kwargs["distillation"] = distillation
45 | model, diffusion = create_model_and_diffusion(**model_and_diffusion_kwargs)
46 |
47 | elif "consistency" in args.training_mode:
48 | distillation = True
49 | model_and_diffusion_kwargs["distillation"] = distillation
50 | model, diffusion = create_model_and_diffusion(**model_and_diffusion_kwargs)
51 |
52 | elif args.training_mode == "one_shot_pinn_edm_edm":
53 | student_model_and_diffusion_kwargs = copy.deepcopy(model_and_diffusion_kwargs)
54 |
55 |
56 | student_model_and_diffusion_kwargs["random_init"] = False
57 |
58 | model, diffusion = create_one_shot_edmedm_model_and_diffusion(**student_model_and_diffusion_kwargs)
59 |
60 | else:
61 | raise ValueError(f"unknown training mode {args.training_mode}")
62 |
63 |
64 | model.to(dist_util.dev())
65 | model.train()
66 |
67 | if args.use_fp16:
68 | model.convert_to_fp16()
69 |
70 | # A distribution over timesteps in the diffusion process, intended to reduce
71 | # variance of the objective.
72 | schedule_sampler = create_named_schedule_sampler(args.schedule_sampler, diffusion)
73 |
74 | if args.batch_size == -1:
75 | batch_size = args.global_batch_size // dist.get_world_size()
76 | if args.global_batch_size % dist.get_world_size() != 0:
77 | logger.log(
78 | f"warning, using smaller global_batch_size of {dist.get_world_size()*batch_size} instead of {args.global_batch_size}"
79 | )
80 | else:
81 | batch_size = args.batch_size
82 | # batch_size = 2048 which is the batch_size for each gpu
83 |
84 | data = None
85 |
86 | if len(args.teacher_model_path) > 0: # path to the teacher score model.
87 | logger.log(f"loading the teacher model from {args.teacher_model_path}")
88 | teacher_model_and_diffusion_kwargs = copy.deepcopy(model_and_diffusion_kwargs)
89 | teacher_model_and_diffusion_kwargs["dropout"] = args.teacher_dropout # 0.1
90 | teacher_model_and_diffusion_kwargs["distillation"] = False
91 | teacher_model_and_diffusion_kwargs["random_init"] = False
92 |
93 | if args.training_mode == "one_shot_pinn_edm_edm":
94 | teacher_model_and_diffusion_kwargs["teacher_precond"] = True
95 | teacher_model, teacher_diffusion = create_one_shot_edmedm_model_and_diffusion(**teacher_model_and_diffusion_kwargs)
96 | load_weights = dist_util.load_state_dict(args.teacher_model_path, map_location="cpu")
97 | new_state_dict = {}
98 | for k, v in load_weights.items():
99 | if "map_augment" in k:
100 | continue
101 | new_key = k.replace("model.", "")
102 | new_state_dict[new_key] = v
103 | teacher_model.load_state_dict(new_state_dict)
104 |
105 | model.load_state_dict(new_state_dict)
106 |
107 | else:
108 | teacher_model, teacher_diffusion = create_model_and_diffusion(
109 | **teacher_model_and_diffusion_kwargs,
110 | )
111 | teacher_model.load_state_dict(
112 | dist_util.load_state_dict(args.teacher_model_path, map_location="cpu"),
113 | )
114 |
115 | teacher_model.to(dist_util.dev())
116 | teacher_model.eval()
117 |
118 |
119 | if args.use_fp16:
120 | teacher_model.convert_to_fp16()
121 |
122 | else:
123 | teacher_model = None
124 | teacher_diffusion = None
125 |
126 | logger.log("training...")
127 | ODETrainLoop(
128 | model=model,
129 | teacher_model=teacher_model,
130 | teacher_diffusion=teacher_diffusion,
131 | training_mode=args.training_mode,
132 | ema_scale_fn=ema_scale_fn,
133 | total_training_steps=args.total_training_steps, # 600000
134 | diffusion=diffusion,
135 | data=data,
136 | batch_size=batch_size,
137 | microbatch=args.microbatch, # -1
138 | lr=args.lr, # 1e-4
139 | ema_rate=args.ema_rate, # 0.999,0.9999,0.9999432189950708
140 | log_interval=args.log_interval, # 10
141 | save_interval=args.save_interval, # 10k
142 | resume_checkpoint=args.resume_checkpoint,
143 | use_fp16=args.use_fp16, # True
144 | fp16_scale_growth=args.fp16_scale_growth, # 1e-3
145 | schedule_sampler=schedule_sampler,
146 | weight_decay=args.weight_decay, # 0
147 | lr_anneal_steps=args.lr_anneal_steps, # 0
148 | methodology=args.methodology,
149 | optimizer=args.optimizer,
150 | opt_eps=args.opt_eps,
151 | eval_interval=args.eval_interval,
152 | ).run_loop()
153 |
154 |
155 | def create_argparser():
156 | defaults = dict(
157 | data_dir="../cifar10/train",
158 | schedule_sampler="uniform",
159 | lr=1e-4,
160 | weight_decay=0.0,
161 | lr_anneal_steps=0,
162 | global_batch_size=2048,
163 | batch_size=-1,
164 | microbatch=-1, # -1 disables microbatches
165 | ema_rate="0.9999", # comma-separated list of EMA values
166 | log_interval=10,
167 | save_interval=10000,
168 | resume_checkpoint="",
169 | use_fp16=False,
170 | fp16_scale_growth=1e-3,
171 | methodology="Euler",
172 | use_target_model=False,
173 | optimizer='radam',
174 | opt_eps=1e-8,
175 | eval_interval=10000,
176 | random_init_stu=False,
177 | )
178 | defaults.update(model_and_diffusion_defaults())
179 | defaults.update(cm_train_defaults())
180 | parser = argparse.ArgumentParser()
181 | add_dict_to_argparser(parser, defaults)
182 | return parser
183 |
184 |
185 | if __name__ == "__main__":
186 | main()
187 |
--------------------------------------------------------------------------------
/cm/resample.py:
--------------------------------------------------------------------------------
1 | from abc import ABC, abstractmethod
2 |
3 | import numpy as np
4 | import torch as th
5 | from scipy.stats import norm
6 | import torch.distributed as dist
7 |
8 |
9 | def create_named_schedule_sampler(name, diffusion):
10 | """
11 | Create a ScheduleSampler from a library of pre-defined samplers.
12 |
13 | :param name: the name of the sampler.
14 | :param diffusion: the diffusion object to sample for.
15 | """
16 | if name == "uniform":
17 | return UniformSampler(diffusion)
18 | elif name == "loss-second-moment":
19 | return LossSecondMomentResampler(diffusion)
20 | elif name == "lognormal":
21 | return LogNormalSampler()
22 | else:
23 | raise NotImplementedError(f"unknown schedule sampler: {name}")
24 |
25 |
26 | class ScheduleSampler(ABC):
27 | """
28 | A distribution over timesteps in the diffusion process, intended to reduce
29 | variance of the objective.
30 |
31 | By default, samplers perform unbiased importance sampling, in which the
32 | objective's mean is unchanged.
33 | However, subclasses may override sample() to change how the resampled
34 | terms are reweighted, allowing for actual changes in the objective.
35 | """
36 |
37 | @abstractmethod
38 | def weights(self):
39 | """
40 | Get a numpy array of weights, one per diffusion step.
41 |
42 | The weights needn't be normalized, but must be positive.
43 | """
44 |
45 | def sample(self, batch_size, device):
46 | """
47 | Importance-sample timesteps for a batch.
48 |
49 | :param batch_size: the number of timesteps.
50 | :param device: the torch device to save to.
51 | :return: a tuple (timesteps, weights):
52 | - timesteps: a tensor of timestep indices.
53 | - weights: a tensor of weights to scale the resulting losses.
54 | """
55 | w = self.weights()
56 | p = w / np.sum(w)
57 | indices_np = np.random.choice(len(p), size=(batch_size,), p=p)
58 | indices = th.from_numpy(indices_np).long().to(device)
59 | weights_np = 1 / (len(p) * p[indices_np])
60 | weights = th.from_numpy(weights_np).float().to(device)
61 | return indices, weights
62 |
63 |
64 | class UniformSampler(ScheduleSampler):
65 | def __init__(self, diffusion):
66 | self.diffusion = diffusion
67 | self._weights = np.ones([diffusion.num_timesteps])
68 |
69 | def weights(self):
70 | return self._weights
71 |
72 |
73 | class LossAwareSampler(ScheduleSampler):
74 | def update_with_local_losses(self, local_ts, local_losses):
75 | """
76 | Update the reweighting using losses from a model.
77 |
78 | Call this method from each rank with a batch of timesteps and the
79 | corresponding losses for each of those timesteps.
80 | This method will perform synchronization to make sure all of the ranks
81 | maintain the exact same reweighting.
82 |
83 | :param local_ts: an integer Tensor of timesteps.
84 | :param local_losses: a 1D Tensor of losses.
85 | """
86 | batch_sizes = [
87 | th.tensor([0], dtype=th.int32, device=local_ts.device)
88 | for _ in range(dist.get_world_size())
89 | ]
90 | dist.all_gather(
91 | batch_sizes,
92 | th.tensor([len(local_ts)], dtype=th.int32, device=local_ts.device),
93 | )
94 |
95 | # Pad all_gather batches to be the maximum batch size.
96 | batch_sizes = [x.item() for x in batch_sizes]
97 | max_bs = max(batch_sizes)
98 |
99 | timestep_batches = [th.zeros(max_bs).to(local_ts) for bs in batch_sizes]
100 | loss_batches = [th.zeros(max_bs).to(local_losses) for bs in batch_sizes]
101 | dist.all_gather(timestep_batches, local_ts)
102 | dist.all_gather(loss_batches, local_losses)
103 | timesteps = [
104 | x.item() for y, bs in zip(timestep_batches, batch_sizes) for x in y[:bs]
105 | ]
106 | losses = [x.item() for y, bs in zip(loss_batches, batch_sizes) for x in y[:bs]]
107 | self.update_with_all_losses(timesteps, losses)
108 |
109 | @abstractmethod
110 | def update_with_all_losses(self, ts, losses):
111 | """
112 | Update the reweighting using losses from a model.
113 |
114 | Sub-classes should override this method to update the reweighting
115 | using losses from the model.
116 |
117 | This method directly updates the reweighting without synchronizing
118 | between workers. It is called by update_with_local_losses from all
119 | ranks with identical arguments. Thus, it should have deterministic
120 | behavior to maintain state across workers.
121 |
122 | :param ts: a list of int timesteps.
123 | :param losses: a list of float losses, one per timestep.
124 | """
125 |
126 |
127 | class LossSecondMomentResampler(LossAwareSampler):
128 | def __init__(self, diffusion, history_per_term=10, uniform_prob=0.001):
129 | self.diffusion = diffusion
130 | self.history_per_term = history_per_term
131 | self.uniform_prob = uniform_prob
132 | self._loss_history = np.zeros(
133 | [diffusion.num_timesteps, history_per_term], dtype=np.float64
134 | )
135 | self._loss_counts = np.zeros([diffusion.num_timesteps], dtype=np.int)
136 |
137 | def weights(self):
138 | if not self._warmed_up():
139 | return np.ones([self.diffusion.num_timesteps], dtype=np.float64)
140 | weights = np.sqrt(np.mean(self._loss_history**2, axis=-1))
141 | weights /= np.sum(weights)
142 | weights *= 1 - self.uniform_prob
143 | weights += self.uniform_prob / len(weights)
144 | return weights
145 |
146 | def update_with_all_losses(self, ts, losses):
147 | for t, loss in zip(ts, losses):
148 | if self._loss_counts[t] == self.history_per_term:
149 | # Shift out the oldest loss term.
150 | self._loss_history[t, :-1] = self._loss_history[t, 1:]
151 | self._loss_history[t, -1] = loss
152 | else:
153 | self._loss_history[t, self._loss_counts[t]] = loss
154 | self._loss_counts[t] += 1
155 |
156 | def _warmed_up(self):
157 | return (self._loss_counts == self.history_per_term).all()
158 |
159 |
160 | class LogNormalSampler:
161 | def __init__(self, p_mean=-1.2, p_std=1.2, even=False):
162 | self.p_mean = p_mean
163 | self.p_std = p_std
164 | self.even = even
165 | if self.even:
166 | self.inv_cdf = lambda x: norm.ppf(x, loc=p_mean, scale=p_std)
167 | self.rank, self.size = dist.get_rank(), dist.get_world_size()
168 |
169 | def sample(self, bs, device):
170 | if self.even:
171 | # buckets = [1/G]
172 | start_i, end_i = self.rank * bs, (self.rank + 1) * bs
173 | global_batch_size = self.size * bs
174 | locs = (th.arange(start_i, end_i) + th.rand(bs)) / global_batch_size
175 | log_sigmas = th.tensor(self.inv_cdf(locs), dtype=th.float32, device=device)
176 | else:
177 | log_sigmas = self.p_mean + self.p_std * th.randn(bs, device=device)
178 | sigmas = th.exp(log_sigmas)
179 | weights = th.ones_like(sigmas)
180 | return sigmas, weights
181 |
--------------------------------------------------------------------------------
/cm/fp16_util.py:
--------------------------------------------------------------------------------
1 | """
2 | Helpers to train with 16-bit precision.
3 | """
4 |
5 | import numpy as np
6 | import torch as th
7 | import torch.nn as nn
8 | from torch._utils import _flatten_dense_tensors, _unflatten_dense_tensors
9 |
10 | from . import logger
11 |
12 | INITIAL_LOG_LOSS_SCALE = 20.0
13 | # INITIAL_LOG_LOSS_SCALE = 12.0
14 |
15 |
16 | def convert_module_to_f16(l):
17 | """
18 | Convert primitive modules to float16.
19 | """
20 | if isinstance(l, (nn.Conv1d, nn.Conv2d, nn.Conv3d)):
21 | l.weight.data = l.weight.data.half()
22 | if l.bias is not None:
23 | l.bias.data = l.bias.data.half()
24 |
25 |
26 | def convert_module_to_f32(l):
27 | """
28 | Convert primitive modules to float32, undoing convert_module_to_f16().
29 | """
30 | if isinstance(l, (nn.Conv1d, nn.Conv2d, nn.Conv3d)):
31 | l.weight.data = l.weight.data.float()
32 | if l.bias is not None:
33 | l.bias.data = l.bias.data.float()
34 |
35 |
36 | def make_master_params(param_groups_and_shapes):
37 | """
38 | Copy model parameters into a (differently-shaped) list of full-precision
39 | parameters.
40 | """
41 | master_params = []
42 | for param_group, shape in param_groups_and_shapes:
43 | master_param = nn.Parameter(
44 | _flatten_dense_tensors(
45 | [param.detach().float() for (_, param) in param_group]
46 | ).view(shape)
47 | )
48 | master_param.requires_grad = True
49 | master_params.append(master_param)
50 | return master_params
51 |
52 |
53 | def model_grads_to_master_grads(param_groups_and_shapes, master_params):
54 | """
55 | Copy the gradients from the model parameters into the master parameters
56 | from make_master_params().
57 | """
58 | for master_param, (param_group, shape) in zip(
59 | master_params, param_groups_and_shapes
60 | ):
61 | master_param.grad = _flatten_dense_tensors(
62 | [param_grad_or_zeros(param) for (_, param) in param_group]
63 | ).view(shape)
64 |
65 |
66 | def master_params_to_model_params(param_groups_and_shapes, master_params):
67 | """
68 | Copy the master parameter data back into the model parameters.
69 | """
70 | # Without copying to a list, if a generator is passed, this will
71 | # silently not copy any parameters.
72 | for master_param, (param_group, _) in zip(master_params, param_groups_and_shapes):
73 | for (_, param), unflat_master_param in zip(
74 | param_group, unflatten_master_params(param_group, master_param.view(-1))
75 | ):
76 | param.detach().copy_(unflat_master_param)
77 |
78 |
79 | def unflatten_master_params(param_group, master_param):
80 | return _unflatten_dense_tensors(master_param, [param for (_, param) in param_group])
81 |
82 |
83 | def get_param_groups_and_shapes(named_model_params):
84 | named_model_params = list(named_model_params)
85 | scalar_vector_named_params = (
86 | [(n, p) for (n, p) in named_model_params if p.ndim <= 1],
87 | (-1),
88 | )
89 | matrix_named_params = (
90 | [(n, p) for (n, p) in named_model_params if p.ndim > 1],
91 | (1, -1),
92 | )
93 | return [scalar_vector_named_params, matrix_named_params]
94 |
95 |
96 | def master_params_to_state_dict(
97 | model, param_groups_and_shapes, master_params, use_fp16
98 | ):
99 | if use_fp16:
100 | state_dict = model.state_dict()
101 | for master_param, (param_group, _) in zip(
102 | master_params, param_groups_and_shapes
103 | ):
104 | for (name, _), unflat_master_param in zip(
105 | param_group, unflatten_master_params(param_group, master_param.view(-1))
106 | ):
107 | assert name in state_dict
108 | state_dict[name] = unflat_master_param
109 | else:
110 | state_dict = model.state_dict()
111 | for i, (name, _value) in enumerate(model.named_parameters()):
112 | assert name in state_dict
113 | state_dict[name] = master_params[i]
114 | return state_dict
115 |
116 |
117 | def state_dict_to_master_params(model, state_dict, use_fp16):
118 | if use_fp16:
119 | named_model_params = [
120 | (name, state_dict[name]) for name, _ in model.named_parameters()
121 | ]
122 | param_groups_and_shapes = get_param_groups_and_shapes(named_model_params)
123 | master_params = make_master_params(param_groups_and_shapes)
124 | else:
125 | master_params = [state_dict[name] for name, _ in model.named_parameters()]
126 | return master_params
127 |
128 |
129 | def zero_master_grads(master_params):
130 | for param in master_params:
131 | param.grad = None
132 |
133 |
134 | def zero_grad(model_params):
135 | for param in model_params:
136 | # Taken from https://pytorch.org/docs/stable/_modules/torch/optim/optimizer.html#Optimizer.add_param_group
137 | if param.grad is not None:
138 | param.grad.detach_()
139 | param.grad.zero_()
140 |
141 |
142 | def param_grad_or_zeros(param):
143 | if param.grad is not None:
144 | return param.grad.data.detach()
145 | else:
146 | return th.zeros_like(param)
147 |
148 |
149 | class MixedPrecisionTrainer:
150 | def __init__(
151 | self,
152 | *,
153 | model,
154 | use_fp16=False,
155 | fp16_scale_growth=1e-3,
156 | initial_lg_loss_scale=INITIAL_LOG_LOSS_SCALE,
157 | ):
158 | self.model = model
159 | self.use_fp16 = use_fp16
160 | self.fp16_scale_growth = fp16_scale_growth
161 |
162 | self.model_params = list(self.model.parameters())
163 |
164 | self.master_params = self.model_params
165 | self.param_groups_and_shapes = None
166 | self.lg_loss_scale = initial_lg_loss_scale
167 |
168 | if self.use_fp16:
169 | self.param_groups_and_shapes = get_param_groups_and_shapes(
170 | self.model.named_parameters()
171 | )
172 | self.master_params = make_master_params(self.param_groups_and_shapes)
173 | self.model.convert_to_fp16()
174 |
175 | def zero_grad(self):
176 | zero_grad(self.model_params)
177 |
178 | def backward(self, loss: th.Tensor):
179 | if self.use_fp16:
180 | loss_scale = 2**self.lg_loss_scale
181 | (loss * loss_scale).backward()
182 | else:
183 | loss.backward()
184 |
185 | def optimize(self, opt: th.optim.Optimizer):
186 | if self.use_fp16:
187 | return self._optimize_fp16(opt)
188 | else:
189 | return self._optimize_normal(opt)
190 |
191 | def _optimize_fp16(self, opt: th.optim.Optimizer):
192 | logger.logkv_mean("lg_loss_scale", self.lg_loss_scale)
193 | model_grads_to_master_grads(self.param_groups_and_shapes, self.master_params)
194 | grad_norm, param_norm = self._compute_norms(grad_scale=2**self.lg_loss_scale)
195 | if check_overflow(grad_norm):
196 | self.lg_loss_scale -= 1
197 | logger.log(f"Found NaN, decreased lg_loss_scale to {self.lg_loss_scale}")
198 | zero_master_grads(self.master_params)
199 | return False
200 |
201 | logger.logkv_mean("grad_norm", grad_norm)
202 | logger.logkv_mean("param_norm", param_norm)
203 |
204 | for p in self.master_params:
205 | p.grad.mul_(1.0 / (2**self.lg_loss_scale))
206 | # th.nn.utils.clip_grad_norm_(self.master_params, 1.)
207 | opt.step()
208 | zero_master_grads(self.master_params)
209 | master_params_to_model_params(self.param_groups_and_shapes, self.master_params)
210 | self.lg_loss_scale += self.fp16_scale_growth
211 | return True
212 |
213 | def _optimize_normal(self, opt: th.optim.Optimizer):
214 | grad_norm, param_norm = self._compute_norms()
215 | logger.logkv_mean("grad_norm", grad_norm)
216 | logger.logkv_mean("param_norm", param_norm)
217 | # th.nn.utils.clip_grad_norm_(self.master_params, 1.)
218 | opt.step()
219 | return True
220 |
221 | def _compute_norms(self, grad_scale=1.0):
222 | grad_norm = 0.0
223 | param_norm = 0.0
224 | for p in self.master_params:
225 | with th.no_grad():
226 | param_norm += th.norm(p, p=2, dtype=th.float32).item() ** 2
227 | if p.grad is not None:
228 | grad_norm += th.norm(p.grad, p=2, dtype=th.float32).item() ** 2
229 | return np.sqrt(grad_norm) / grad_scale, np.sqrt(param_norm)
230 |
231 | def master_params_to_state_dict(self, master_params):
232 | return master_params_to_state_dict(
233 | self.model, self.param_groups_and_shapes, master_params, self.use_fp16
234 | )
235 |
236 | def state_dict_to_master_params(self, state_dict):
237 | return state_dict_to_master_params(self.model, state_dict, self.use_fp16)
238 |
239 | def check_overflow(value):
240 | return (value == float("inf")) or (value == -float("inf")) or (value != value)
241 |
--------------------------------------------------------------------------------
/scripts/fid_evaluation.py:
--------------------------------------------------------------------------------
1 | """
2 | Generate a large batch of image samples from a model and save them as a large
3 | numpy array. This can be used to produce samples for FID evaluation.
4 | """
5 |
6 | import argparse
7 | import os
8 |
9 | import numpy as np
10 | import torch as th
11 | import torch.distributed as dist
12 |
13 | from cm import dist_util, logger
14 | from cm.script_util import (
15 | NUM_CLASSES,
16 | model_and_diffusion_defaults,
17 | create_model_and_diffusion,
18 | add_dict_to_argparser,
19 | args_to_dict,
20 | create_one_shot_edmedm_model_and_diffusion,
21 | )
22 | from cm.random_util import get_generator
23 | from cm.karras_diffusion import karras_sample
24 | import torchvision
25 | import PIL
26 | from cleanfid.features import build_feature_extractor, get_reference_statistics
27 | import scipy.linalg
28 | import glob
29 | import csv
30 | from pathlib import Path
31 | import pandas
32 |
33 | def calculate_fid_from_inception_stats(mu, sigma, mu_ref, sigma_ref):
34 | m = np.square(mu - mu_ref).sum()
35 | s, _ = scipy.linalg.sqrtm(np.dot(sigma, sigma_ref), disp=False)
36 | fid = m + np.trace(sigma + sigma_ref - s * 2)
37 | return float(np.real(fid))
38 |
39 | def main(args, model=None, diffusion=None):
40 |
41 | if model==None or diffusion==None:
42 |
43 | if "one_shot_pinn_edm_edm_teacher" == args.training_mode:
44 | model, diffusion = create_one_shot_edmedm_model_and_diffusion(teacher_precond=True,
45 | **args_to_dict(args, model_and_diffusion_defaults().keys()),
46 | )
47 | load_weights = dist_util.load_state_dict(args.model_path, map_location="cpu")
48 | new_state_dict = {}
49 | for k, v in load_weights.items():
50 | if "map_augment" in k:
51 | continue
52 | new_key = k.replace("model.", "")
53 | new_state_dict[new_key] = v
54 |
55 | model.load_state_dict(new_state_dict)
56 | elif "one_shot_pinn_edm_edm_one_shot" == args.training_mode:
57 | model, diffusion = create_one_shot_edmedm_model_and_diffusion(teacher_precond=False,
58 | **args_to_dict(args, model_and_diffusion_defaults().keys()),
59 | )
60 | load_weights = dist_util.load_state_dict(args.model_path, map_location="cpu")
61 | new_state_dict = {}
62 | for k, v in load_weights.items():
63 | if "map_augment" in k:
64 | continue
65 | new_key = k.replace("model.", "")
66 | new_state_dict[new_key] = v
67 |
68 | model.load_state_dict(new_state_dict)
69 | else:
70 | raise ValueError(f"training mode {args.training_mode} not supported")
71 |
72 | model.to(dist_util.dev())
73 | if args.use_fp16:
74 | model.convert_to_fp16()
75 | model.eval()
76 |
77 | logger.log("sampling...")
78 | if args.sampler == "multistep":
79 | assert len(args.ts) > 0
80 | ts = tuple(int(x) for x in args.ts.split(","))
81 | else:
82 | ts = None
83 |
84 |
85 | mode='legacy_tensorflow'
86 | fid_evaluation_feat_model = build_feature_extractor(mode, dist_util.dev(), use_dataparallel=False)
87 |
88 | if dist.get_rank() == 0:
89 | dataset_name=args.fid_dataset
90 | if dataset_name == 'cifar10':
91 | fpath = './model_zoo/stats/cifar10-32x32.npz'
92 | elif dataset_name == 'imagenet':
93 | fpath = './model_zoo/stats/imagenet-64x64.npz'
94 | else:
95 | raise ValueError(f"fid evaluation error: not support dataset {dataset_name}.")
96 | stats = np.load(fpath)
97 | ref_mu, ref_sigma = stats["mu"], stats["sigma"]
98 |
99 |
100 | all_images = []
101 | all_labels = []
102 | generator = get_generator(args.generator, args.num_samples, args.seed)
103 |
104 | feature_dim = 2048
105 | mu = th.zeros([feature_dim], dtype=th.float64, device=dist_util.dev())
106 | sigma = th.zeros([feature_dim, feature_dim], dtype=th.float64, device=dist_util.dev())
107 | l_feats = []
108 |
109 | generated_img = False
110 | while len(all_images) * args.batch_size < args.num_samples:
111 | model_kwargs = {}
112 | if args.class_cond:
113 | classes = th.randint(
114 | low=0, high=NUM_CLASSES, size=(args.batch_size,), device=dist_util.dev()
115 | )
116 | model_kwargs["y"] = classes
117 |
118 | sample_ori = karras_sample(
119 | diffusion,
120 | model,
121 | (args.batch_size, 3, args.image_size, args.image_size),
122 | steps=args.steps,
123 | model_kwargs=model_kwargs,
124 | device=dist_util.dev(),
125 | clip_denoised=args.clip_denoised,
126 | sampler=args.sampler,
127 | sigma_min=args.sigma_min,
128 | sigma_max=args.sigma_max,
129 | s_churn=args.s_churn,
130 | s_tmin=args.s_tmin,
131 | s_tmax=args.s_tmax,
132 | s_noise=args.s_noise,
133 | generator=generator,
134 | ts=ts,
135 | )
136 | sample = ((sample_ori + 1) * 127.5).clamp(0, 255).to(th.uint8)
137 | sample = sample.permute(0, 2, 3, 1)
138 | sample = sample.contiguous()
139 |
140 | gathered_samples = [th.zeros_like(sample) for _ in range(dist.get_world_size())]
141 | dist.all_gather(gathered_samples, sample) # gather not supported with NCCL
142 | all_images.extend([sample.cpu().numpy() for sample in gathered_samples])
143 | if args.class_cond:
144 | gathered_labels = [
145 | th.zeros_like(classes) for _ in range(dist.get_world_size())
146 | ]
147 | dist.all_gather(gathered_labels, classes)
148 | all_labels.extend([labels.cpu().numpy() for labels in gathered_labels])
149 | logger.log(f"created {len(all_images) * args.batch_size} samples")
150 |
151 | with th.no_grad():
152 | feat = fid_evaluation_feat_model(((sample_ori + 1.) * 0.5).mul(255).clip(0, 255).to(dist_util.dev())).to(th.float64)
153 | # l_feats.append(feat.cpu())
154 | mu += feat.sum(0)
155 | sigma += feat.T @ feat
156 |
157 | if not generated_img and dist.get_rank() == 0:
158 | generated_img = True
159 | torchvision.utils.save_image((sample_ori+1.)/2., os.path.join(logger.get_dir(), f"{args.model_name}_samples.png"), nrow = 10)
160 |
161 |
162 | mu = mu.unsqueeze(0)
163 | sigma = sigma.unsqueeze(0)
164 |
165 | all_mu = [th.zeros_like(mu) for _ in range(dist.get_world_size())]
166 | dist.all_gather(all_mu, mu) # gather not supported with NCCL
167 | all_mu = th.cat(all_mu, axis=0)
168 |
169 | all_sigma = [th.zeros_like(sigma) for _ in range(dist.get_world_size())]
170 | dist.all_gather(all_sigma, sigma) # gather not supported with NCCL
171 | all_sigma = th.cat(all_sigma, axis=0)
172 |
173 | mu = all_mu.sum(0)
174 | sigma = all_sigma.sum(0)
175 |
176 | num_images = args.num_samples
177 | mu /= num_images
178 | sigma -= mu.ger(mu) * num_images
179 | sigma /= num_images - 1
180 |
181 | mu = mu.cpu().numpy()
182 | sigma = sigma.cpu().numpy()
183 |
184 |
185 | arr = np.concatenate(all_images, axis=0)
186 | arr = arr[: args.num_samples]
187 | if args.class_cond:
188 | label_arr = np.concatenate(all_labels, axis=0)
189 | label_arr = label_arr[: args.num_samples]
190 | fid_score = 0.
191 | if dist.get_rank() == 0:
192 |
193 | shape_str = "x".join([str(x) for x in arr.shape])
194 | out_path = os.path.join(logger.get_dir(), f"{args.model_name}_samples_{shape_str}.npz")
195 | logger.log(f"saving to {out_path}")
196 |
197 | if args.class_cond:
198 | np.savez(out_path, arr, label_arr)
199 | else:
200 | np.savez(out_path, arr)
201 |
202 |
203 | fid_score = calculate_fid_from_inception_stats(
204 | mu, sigma,
205 | ref_mu,
206 | ref_sigma
207 | )
208 |
209 | dist.barrier()
210 | logger.log("sampling complete")
211 | return fid_score
212 |
213 |
214 | def create_argparser():
215 | defaults = dict(
216 | training_mode="edm",
217 | generator="determ",
218 | clip_denoised=True,
219 | num_samples=10000,
220 | batch_size=16,
221 | sampler="heun",
222 | s_churn=0.0,
223 | s_tmin=0.0,
224 | s_tmax=float("inf"),
225 | s_noise=1.0,
226 | steps=40,
227 | model_path="",
228 | seed=42,
229 | ts="",
230 | fid_dataset="cifar10",
231 | )
232 | defaults.update(model_and_diffusion_defaults())
233 | parser = argparse.ArgumentParser()
234 | parser.add_argument('--exp_dir', type=str)
235 | add_dict_to_argparser(parser, defaults)
236 | return parser
237 |
238 |
239 | if __name__ == "__main__":
240 | args = create_argparser().parse_args()
241 | exp_dir = Path(args.exp_dir)
242 | os.environ["OPENAI_LOGDIR"] = str(exp_dir / "FID")
243 |
244 | dist_util.setup_dist()
245 | logger.configure()
246 | assert args.num_samples % (args.batch_size * dist.get_world_size()) == 0
247 |
248 | result_file = exp_dir / f"fid_results_{args.seed}.csv"
249 | if result_file.exists():
250 | logger.log("exist results, check result...")
251 | df = pandas.read_csv(str(result_file))
252 | tested_model = list(df["model_name"])
253 | logger.log(f"Tested model: {tested_model}")
254 | else:
255 | tested_model = []
256 | if dist.get_rank() == 0:
257 | with open(str(result_file), mode='w') as f:
258 | fid_writer = csv.writer(f, delimiter=',')
259 | fid_writer.writerow(['model_name', 'FID'])
260 |
261 | model_list_ = exp_dir.glob("*.pt")
262 | model_list = []
263 |
264 | for model_dir in model_list_:
265 | model_name = str(model_dir.stem)
266 | model_dir = str(model_dir)
267 | model_list.append(
268 | {
269 | "model_name": model_name,
270 | "path": model_dir,
271 | }
272 | )
273 |
274 | for model_test in model_list:
275 | args.model_path = model_test["path"]
276 | args.model_name = model_test["model_name"]
277 | logger.log(f"\nmodel: {args.model_name}")
278 |
279 | if args.model_name in tested_model:
280 | continue
281 |
282 | fid_score = main(args)
283 |
284 | logger.log(f"\nmodel: {args.model_name} \nFID {fid_score:.4f}\n")
285 |
286 | if dist.get_rank() == 0:
287 | with open(str(result_file), mode='a') as f:
288 | fid_writer = csv.writer(f, delimiter=',')
289 | fid_writer.writerow([args.model_name, fid_score])
290 |
291 |
--------------------------------------------------------------------------------
/cm/script_util.py:
--------------------------------------------------------------------------------
1 | import argparse
2 |
3 | from .karras_diffusion import KarrasDenoiser, OneShotDenoiser, EDMEDMDenoiser
4 | from .unet import UNetModel
5 | import numpy as np
6 |
7 | NUM_CLASSES = 1000
8 |
9 |
10 | def cm_train_defaults():
11 | return dict(
12 | teacher_model_path="",
13 | teacher_dropout=0.1,
14 | training_mode="consistency_distillation",
15 | target_ema_mode="fixed",
16 | scale_mode="fixed",
17 | total_training_steps=600000,
18 | start_ema=0.0,
19 | start_scales=40,
20 | end_scales=40,
21 | distill_steps_per_iter=50000,
22 | loss_norm="lpips",
23 | )
24 |
25 |
26 | def model_and_diffusion_defaults():
27 | """
28 | Defaults for image training.
29 | """
30 | res = dict(
31 | sigma_min=0.002,
32 | sigma_max=80.0,
33 | image_size=64,
34 | num_channels=128,
35 | num_res_blocks=2,
36 | num_heads=4,
37 | num_heads_upsample=-1,
38 | num_head_channels=-1,
39 | attention_resolutions="32,16,8",
40 | channel_mult="",
41 | dropout=0.0,
42 | class_cond=False,
43 | use_checkpoint=False,
44 | use_scale_shift_norm=True,
45 | resblock_updown=False,
46 | use_fp16=False,
47 | use_new_attention_order=False,
48 | learn_sigma=False,
49 | weight_schedule="karras",
50 | loss_norm="lpips",
51 | continuous=False,
52 | )
53 | return res
54 |
55 |
56 | def create_model_and_diffusion(
57 | image_size,
58 | class_cond,
59 | learn_sigma,
60 | num_channels,
61 | num_res_blocks,
62 | channel_mult,
63 | num_heads,
64 | num_head_channels,
65 | num_heads_upsample,
66 | attention_resolutions,
67 | dropout,
68 | use_checkpoint,
69 | use_scale_shift_norm,
70 | resblock_updown,
71 | use_fp16,
72 | use_new_attention_order,
73 | weight_schedule,
74 | sigma_min=0.002,
75 | sigma_max=80.0,
76 | distillation=False,
77 | loss_norm=None,
78 | continuous=None,
79 | ):
80 | model = create_model(
81 | image_size,
82 | num_channels,
83 | num_res_blocks,
84 | channel_mult=channel_mult,
85 | learn_sigma=learn_sigma,
86 | class_cond=class_cond,
87 | use_checkpoint=use_checkpoint,
88 | attention_resolutions=attention_resolutions,
89 | num_heads=num_heads,
90 | num_head_channels=num_head_channels,
91 | num_heads_upsample=num_heads_upsample,
92 | use_scale_shift_norm=use_scale_shift_norm,
93 | dropout=dropout,
94 | resblock_updown=resblock_updown,
95 | use_fp16=use_fp16,
96 | use_new_attention_order=use_new_attention_order,
97 | )
98 | diffusion = KarrasDenoiser(
99 | sigma_data=0.5,
100 | sigma_max=sigma_max,
101 | sigma_min=sigma_min,
102 | distillation=distillation,
103 | weight_schedule=weight_schedule,
104 | )
105 | return model, diffusion
106 |
107 |
108 | def create_one_shot_edmedm_model_and_diffusion(
109 | image_size,
110 | class_cond,
111 | learn_sigma,
112 | num_channels,
113 | num_res_blocks,
114 | channel_mult,
115 | num_heads,
116 | num_head_channels,
117 | num_heads_upsample,
118 | attention_resolutions,
119 | dropout,
120 | use_checkpoint,
121 | use_scale_shift_norm,
122 | resblock_updown,
123 | use_fp16,
124 | use_new_attention_order,
125 | weight_schedule,
126 | sigma_min=0.002,
127 | sigma_max=80.0,
128 | distillation=False,
129 | teacher_precond=False,
130 | loss_norm="l2",
131 | random_init=False,
132 | continuous=False,
133 | ):
134 | from cm.network import DhariwalUNet, SongUNet
135 | channel_mult__ = channel_mult
136 |
137 | if channel_mult__ == "":
138 | if image_size == 512:
139 | channel_mult = (0.5, 1, 1, 2, 2, 4, 4)
140 | elif image_size == 256:
141 | channel_mult = (1, 1, 2, 2, 4, 4)
142 | elif image_size == 128:
143 | channel_mult = (1, 1, 2, 3, 4)
144 | elif image_size == 64:
145 | channel_mult = (1, 2, 3, 4)
146 | elif image_size == 32:
147 | channel_mult = (2,2,2)
148 | else:
149 | raise ValueError(f"unsupported image size: {image_size}")
150 | else:
151 | channel_mult = tuple(int(ch_mult) for ch_mult in channel_mult__.split(","))
152 |
153 | attention_ds = []
154 | for res in attention_resolutions.split(","):
155 | attention_ds.append(image_size // int(res))
156 |
157 | t_rescale = 1.
158 | if image_size == 32:
159 | model = SongUNet(
160 | image_size=image_size,
161 | in_channels=3,
162 | model_channels=num_channels,
163 | out_channels=(3 if not learn_sigma else 6),
164 | num_res_blocks=num_res_blocks,
165 | attention_resolutions=tuple(attention_ds),
166 | dropout=dropout,
167 | channel_mult=channel_mult,
168 | num_classes=(10 if class_cond else None),
169 | use_checkpoint=use_checkpoint,
170 | use_fp16=use_fp16,
171 | num_heads=num_heads,
172 | num_head_channels=num_head_channels,
173 | num_heads_upsample=num_heads_upsample,
174 | use_scale_shift_norm=use_scale_shift_norm,
175 | resblock_updown=resblock_updown,
176 | use_new_attention_order=use_new_attention_order,
177 | random_init=random_init,
178 | )
179 | elif image_size == 64:
180 | model = DhariwalUNet(
181 | image_size=image_size,
182 | in_channels=3,
183 | model_channels=num_channels,
184 | out_channels=(3 if not learn_sigma else 6),
185 | num_res_blocks=num_res_blocks,
186 | attention_resolutions=tuple(attention_ds),
187 | dropout=dropout,
188 | channel_mult=channel_mult,
189 | num_classes=(NUM_CLASSES if class_cond else None),
190 | use_checkpoint=use_checkpoint,
191 | use_fp16=use_fp16,
192 | num_heads=num_heads,
193 | num_head_channels=num_head_channels,
194 | num_heads_upsample=num_heads_upsample,
195 | use_scale_shift_norm=use_scale_shift_norm,
196 | resblock_updown=resblock_updown,
197 | use_new_attention_order=use_new_attention_order,
198 | )
199 |
200 |
201 | if teacher_precond:
202 | diffusion = EDMEDMDenoiser(
203 | sigma_data=0.5,
204 | sigma_max=sigma_max,
205 | sigma_min=sigma_min,
206 | distillation=distillation,
207 | weight_schedule=weight_schedule,
208 | t_rescale=t_rescale,
209 | )
210 | else:
211 | diffusion = OneShotDenoiser(
212 | sigma_data=0.5,
213 | sigma_max=sigma_max,
214 | sigma_min=sigma_min,
215 | distillation=distillation,
216 | weight_schedule=weight_schedule,
217 | loss_norm=loss_norm,
218 | t_rescale=t_rescale,
219 | )
220 | return model, diffusion
221 |
222 | def create_model(
223 | image_size,
224 | num_channels,
225 | num_res_blocks,
226 | channel_mult="",
227 | learn_sigma=False,
228 | class_cond=False,
229 | use_checkpoint=False,
230 | attention_resolutions="16",
231 | num_heads=1,
232 | num_head_channels=-1,
233 | num_heads_upsample=-1,
234 | use_scale_shift_norm=False,
235 | dropout=0,
236 | resblock_updown=False,
237 | use_fp16=False,
238 | use_new_attention_order=False,
239 | ):
240 | if channel_mult == "":
241 | if image_size == 512:
242 | channel_mult = (0.5, 1, 1, 2, 2, 4, 4)
243 | elif image_size == 256:
244 | channel_mult = (1, 1, 2, 2, 4, 4)
245 | elif image_size == 128:
246 | channel_mult = (1, 1, 2, 3, 4)
247 | elif image_size == 64:
248 | channel_mult = (1, 2, 3, 4)
249 | else:
250 | raise ValueError(f"unsupported image size: {image_size}")
251 | else:
252 | channel_mult = tuple(int(ch_mult) for ch_mult in channel_mult.split(","))
253 |
254 | attention_ds = []
255 | for res in attention_resolutions.split(","):
256 | attention_ds.append(image_size // int(res))
257 |
258 | return UNetModel(
259 | image_size=image_size,
260 | in_channels=3,
261 | model_channels=num_channels,
262 | out_channels=(3 if not learn_sigma else 6),
263 | num_res_blocks=num_res_blocks,
264 | attention_resolutions=tuple(attention_ds),
265 | dropout=dropout,
266 | channel_mult=channel_mult,
267 | num_classes=(NUM_CLASSES if class_cond else None),
268 | use_checkpoint=use_checkpoint,
269 | use_fp16=use_fp16,
270 | num_heads=num_heads,
271 | num_head_channels=num_head_channels,
272 | num_heads_upsample=num_heads_upsample,
273 | use_scale_shift_norm=use_scale_shift_norm,
274 | resblock_updown=resblock_updown,
275 | use_new_attention_order=use_new_attention_order,
276 | )
277 |
278 |
279 | def create_ema_and_scales_fn(
280 | target_ema_mode,
281 | start_ema,
282 | scale_mode,
283 | start_scales,
284 | end_scales,
285 | total_steps,
286 | distill_steps_per_iter,
287 | ):
288 | def ema_and_scales_fn(step):
289 | if target_ema_mode == "fixed" and scale_mode == "fixed":
290 | target_ema = start_ema
291 | scales = start_scales
292 | elif target_ema_mode == "fixed" and scale_mode == "progressive":
293 | target_ema = start_ema
294 | scales = np.ceil(
295 | np.sqrt(
296 | (step / total_steps) * ((end_scales + 1) ** 2 - start_scales**2)
297 | + start_scales**2
298 | )
299 | - 1
300 | ).astype(np.int32)
301 | scales = np.maximum(scales, 1)
302 | scales = scales + 1
303 |
304 | elif target_ema_mode == "adaptive" and scale_mode == "progressive":
305 | scales = np.ceil(
306 | np.sqrt(
307 | (step / total_steps) * ((end_scales + 1) ** 2 - start_scales**2)
308 | + start_scales**2
309 | )
310 | - 1
311 | ).astype(np.int32)
312 | scales = np.maximum(scales, 1)
313 | c = -np.log(start_ema) * start_scales
314 | target_ema = np.exp(-c / scales)
315 | scales = scales + 1
316 | elif target_ema_mode == "fixed" and scale_mode == "progdist":
317 | distill_stage = step // distill_steps_per_iter
318 | scales = start_scales // (2**distill_stage)
319 | scales = np.maximum(scales, 2)
320 |
321 | sub_stage = np.maximum(
322 | step - distill_steps_per_iter * (np.log2(start_scales) - 1),
323 | 0,
324 | )
325 | sub_stage = sub_stage // (distill_steps_per_iter * 2)
326 | sub_scales = 2 // (2**sub_stage)
327 | sub_scales = np.maximum(sub_scales, 1)
328 |
329 | scales = np.where(scales == 2, sub_scales, scales)
330 |
331 | target_ema = 1.0
332 | else:
333 | raise NotImplementedError
334 |
335 | return float(target_ema), int(scales)
336 |
337 | return ema_and_scales_fn
338 |
339 |
340 | def add_dict_to_argparser(parser, default_dict):
341 | for k, v in default_dict.items():
342 | v_type = type(v)
343 | if v is None:
344 | v_type = str
345 | elif isinstance(v, bool):
346 | v_type = str2bool
347 | parser.add_argument(f"--{k}", default=v, type=v_type)
348 |
349 |
350 | def args_to_dict(args, keys):
351 | return {k: getattr(args, k) for k in keys}
352 |
353 |
354 | def str2bool(v):
355 | """
356 | https://stackoverflow.com/questions/15008758/parsing-boolean-values-with-argparse
357 | """
358 | if isinstance(v, bool):
359 | return v
360 | if v.lower() in ("yes", "true", "t", "y", "1"):
361 | return True
362 | elif v.lower() in ("no", "false", "f", "n", "0"):
363 | return False
364 | else:
365 | raise argparse.ArgumentTypeError("boolean value expected")
366 |
--------------------------------------------------------------------------------
/cm/logger.py:
--------------------------------------------------------------------------------
1 | """
2 | Logger copied from OpenAI baselines to avoid extra RL-based dependencies:
3 | https://github.com/openai/baselines/blob/ea25b9e8b234e6ee1bca43083f8f3cf974143998/baselines/logger.py
4 | """
5 |
6 | import os
7 | import sys
8 | import shutil
9 | import os.path as osp
10 | import json
11 | import time
12 | import datetime
13 | import tempfile
14 | import warnings
15 | from collections import defaultdict
16 | from contextlib import contextmanager
17 |
18 | DEBUG = 10
19 | INFO = 20
20 | WARN = 30
21 | ERROR = 40
22 |
23 | DISABLED = 50
24 |
25 |
26 | class KVWriter(object):
27 | def writekvs(self, kvs):
28 | raise NotImplementedError
29 |
30 |
31 | class SeqWriter(object):
32 | def writeseq(self, seq):
33 | raise NotImplementedError
34 |
35 |
36 | class HumanOutputFormat(KVWriter, SeqWriter):
37 | def __init__(self, filename_or_file):
38 | if isinstance(filename_or_file, str):
39 | self.file = open(filename_or_file, "wt")
40 | self.own_file = True
41 | else:
42 | assert hasattr(filename_or_file, "read"), (
43 | "expected file or str, got %s" % filename_or_file
44 | )
45 | self.file = filename_or_file
46 | self.own_file = False
47 |
48 | def writekvs(self, kvs):
49 | # Create strings for printing
50 | key2str = {}
51 | for (key, val) in sorted(kvs.items()):
52 | if hasattr(val, "__float__"):
53 | valstr = "%-8.3g" % val
54 | else:
55 | valstr = str(val)
56 | key2str[self._truncate(key)] = self._truncate(valstr)
57 |
58 | # Find max widths
59 | if len(key2str) == 0:
60 | print("WARNING: tried to write empty key-value dict")
61 | return
62 | else:
63 | keywidth = max(map(len, key2str.keys()))
64 | valwidth = max(map(len, key2str.values()))
65 |
66 | # Write out the data
67 | dashes = "-" * (keywidth + valwidth + 7)
68 | lines = [dashes]
69 | for (key, val) in sorted(key2str.items(), key=lambda kv: kv[0].lower()):
70 | lines.append(
71 | "| %s%s | %s%s |"
72 | % (key, " " * (keywidth - len(key)), val, " " * (valwidth - len(val)))
73 | )
74 | lines.append(dashes)
75 | self.file.write("\n".join(lines) + "\n")
76 |
77 | # Flush the output to the file
78 | self.file.flush()
79 |
80 | def _truncate(self, s):
81 | maxlen = 30
82 | return s[: maxlen - 3] + "..." if len(s) > maxlen else s
83 |
84 | def writeseq(self, seq):
85 | seq = list(seq)
86 | for (i, elem) in enumerate(seq):
87 | self.file.write(elem)
88 | if i < len(seq) - 1: # add space unless this is the last one
89 | self.file.write(" ")
90 | self.file.write("\n")
91 | self.file.flush()
92 |
93 | def close(self):
94 | if self.own_file:
95 | self.file.close()
96 |
97 |
98 | class JSONOutputFormat(KVWriter):
99 | def __init__(self, filename):
100 | self.file = open(filename, "wt")
101 |
102 | def writekvs(self, kvs):
103 | for k, v in sorted(kvs.items()):
104 | if hasattr(v, "dtype"):
105 | kvs[k] = float(v)
106 | self.file.write(json.dumps(kvs) + "\n")
107 | self.file.flush()
108 |
109 | def close(self):
110 | self.file.close()
111 |
112 |
113 | class CSVOutputFormat(KVWriter):
114 | def __init__(self, filename):
115 | self.file = open(filename, "w+t")
116 | self.keys = []
117 | self.sep = ","
118 |
119 | def writekvs(self, kvs):
120 | # Add our current row to the history
121 | extra_keys = list(kvs.keys() - self.keys)
122 | extra_keys.sort()
123 | if extra_keys:
124 | self.keys.extend(extra_keys)
125 | self.file.seek(0)
126 | lines = self.file.readlines()
127 | self.file.seek(0)
128 | for (i, k) in enumerate(self.keys):
129 | if i > 0:
130 | self.file.write(",")
131 | self.file.write(k)
132 | self.file.write("\n")
133 | for line in lines[1:]:
134 | self.file.write(line[:-1])
135 | self.file.write(self.sep * len(extra_keys))
136 | self.file.write("\n")
137 | for (i, k) in enumerate(self.keys):
138 | if i > 0:
139 | self.file.write(",")
140 | v = kvs.get(k)
141 | if v is not None:
142 | self.file.write(str(v))
143 | self.file.write("\n")
144 | self.file.flush()
145 |
146 | def close(self):
147 | self.file.close()
148 |
149 |
150 | class TensorBoardOutputFormat(KVWriter):
151 | """
152 | Dumps key/value pairs into TensorBoard's numeric format.
153 | """
154 |
155 | def __init__(self, dir):
156 | os.makedirs(dir, exist_ok=True)
157 | self.dir = dir
158 | self.step = 1
159 | prefix = "events"
160 | path = osp.join(osp.abspath(dir), prefix)
161 | import tensorflow as tf
162 | from tensorflow.python import pywrap_tensorflow
163 | from tensorflow.core.util import event_pb2
164 | from tensorflow.python.util import compat
165 |
166 | self.tf = tf
167 | self.event_pb2 = event_pb2
168 | self.pywrap_tensorflow = pywrap_tensorflow
169 | self.writer = pywrap_tensorflow.EventsWriter(compat.as_bytes(path))
170 |
171 | def writekvs(self, kvs):
172 | def summary_val(k, v):
173 | kwargs = {"tag": k, "simple_value": float(v)}
174 | return self.tf.Summary.Value(**kwargs)
175 |
176 | summary = self.tf.Summary(value=[summary_val(k, v) for k, v in kvs.items()])
177 | event = self.event_pb2.Event(wall_time=time.time(), summary=summary)
178 | event.step = (
179 | self.step
180 | ) # is there any reason why you'd want to specify the step?
181 | self.writer.WriteEvent(event)
182 | self.writer.Flush()
183 | self.step += 1
184 |
185 | def close(self):
186 | if self.writer:
187 | self.writer.Close()
188 | self.writer = None
189 |
190 |
191 | def make_output_format(format, ev_dir, log_suffix=""):
192 | os.makedirs(ev_dir, exist_ok=True)
193 | if format == "stdout":
194 | return HumanOutputFormat(sys.stdout)
195 | elif format == "log":
196 | return HumanOutputFormat(osp.join(ev_dir, "log%s.txt" % log_suffix))
197 | elif format == "json":
198 | return JSONOutputFormat(osp.join(ev_dir, "progress%s.json" % log_suffix))
199 | elif format == "csv":
200 | return CSVOutputFormat(osp.join(ev_dir, "progress%s.csv" % log_suffix))
201 | elif format == "tensorboard":
202 | return TensorBoardOutputFormat(osp.join(ev_dir, "tb%s" % log_suffix))
203 | else:
204 | raise ValueError("Unknown format specified: %s" % (format,))
205 |
206 |
207 | # ================================================================
208 | # API
209 | # ================================================================
210 |
211 |
212 | def logkv(key, val):
213 | """
214 | Log a value of some diagnostic
215 | Call this once for each diagnostic quantity, each iteration
216 | If called many times, last value will be used.
217 | """
218 | get_current().logkv(key, val)
219 |
220 |
221 | def logkv_mean(key, val):
222 | """
223 | The same as logkv(), but if called many times, values averaged.
224 | """
225 | get_current().logkv_mean(key, val)
226 |
227 |
228 | def logkvs(d):
229 | """
230 | Log a dictionary of key-value pairs
231 | """
232 | for (k, v) in d.items():
233 | logkv(k, v)
234 |
235 |
236 | def dumpkvs():
237 | """
238 | Write all of the diagnostics from the current iteration
239 | """
240 | return get_current().dumpkvs()
241 |
242 |
243 | def getkvs():
244 | return get_current().name2val
245 |
246 |
247 | def log(*args, level=INFO):
248 | """
249 | Write the sequence of args, with no separators, to the console and output files (if you've configured an output file).
250 | """
251 | get_current().log(*args, level=level)
252 |
253 |
254 | def debug(*args):
255 | log(*args, level=DEBUG)
256 |
257 |
258 | def info(*args):
259 | log(*args, level=INFO)
260 |
261 |
262 | def warn(*args):
263 | log(*args, level=WARN)
264 |
265 |
266 | def error(*args):
267 | log(*args, level=ERROR)
268 |
269 |
270 | def set_level(level):
271 | """
272 | Set logging threshold on current logger.
273 | """
274 | get_current().set_level(level)
275 |
276 |
277 | def set_comm(comm):
278 | get_current().set_comm(comm)
279 |
280 |
281 | def get_dir():
282 | """
283 | Get directory that log files are being written to.
284 | will be None if there is no output directory (i.e., if you didn't call start)
285 | """
286 | return get_current().get_dir()
287 |
288 |
289 | record_tabular = logkv
290 | dump_tabular = dumpkvs
291 |
292 |
293 | @contextmanager
294 | def profile_kv(scopename):
295 | logkey = "wait_" + scopename
296 | tstart = time.time()
297 | try:
298 | yield
299 | finally:
300 | get_current().name2val[logkey] += time.time() - tstart
301 |
302 |
303 | def profile(n):
304 | """
305 | Usage:
306 | @profile("my_func")
307 | def my_func(): code
308 | """
309 |
310 | def decorator_with_name(func):
311 | def func_wrapper(*args, **kwargs):
312 | with profile_kv(n):
313 | return func(*args, **kwargs)
314 |
315 | return func_wrapper
316 |
317 | return decorator_with_name
318 |
319 |
320 | # ================================================================
321 | # Backend
322 | # ================================================================
323 |
324 |
325 | def get_current():
326 | if Logger.CURRENT is None:
327 | _configure_default_logger()
328 |
329 | return Logger.CURRENT
330 |
331 |
332 | class Logger(object):
333 | DEFAULT = None # A logger with no output files. (See right below class definition)
334 | # So that you can still log to the terminal without setting up any output files
335 | CURRENT = None # Current logger being used by the free functions above
336 |
337 | def __init__(self, dir, output_formats, comm=None):
338 | self.name2val = defaultdict(float) # values this iteration
339 | self.name2cnt = defaultdict(int)
340 | self.level = INFO
341 | self.dir = dir
342 | self.output_formats = output_formats
343 | self.comm = comm
344 |
345 | # Logging API, forwarded
346 | # ----------------------------------------
347 | def logkv(self, key, val):
348 | self.name2val[key] = val
349 |
350 | def logkv_mean(self, key, val):
351 | oldval, cnt = self.name2val[key], self.name2cnt[key]
352 | self.name2val[key] = oldval * cnt / (cnt + 1) + val / (cnt + 1)
353 | self.name2cnt[key] = cnt + 1
354 |
355 | def dumpkvs(self):
356 | if self.comm is None:
357 | d = self.name2val
358 | else:
359 | d = mpi_weighted_mean(
360 | self.comm,
361 | {
362 | name: (val, self.name2cnt.get(name, 1))
363 | for (name, val) in self.name2val.items()
364 | },
365 | )
366 | if self.comm.rank != 0:
367 | d["dummy"] = 1 # so we don't get a warning about empty dict
368 | out = d.copy() # Return the dict for unit testing purposes
369 | for fmt in self.output_formats:
370 | if isinstance(fmt, KVWriter):
371 | fmt.writekvs(d)
372 | self.name2val.clear()
373 | self.name2cnt.clear()
374 | return out
375 |
376 | def log(self, *args, level=INFO):
377 | if self.level <= level:
378 | self._do_log(args)
379 |
380 | # Configuration
381 | # ----------------------------------------
382 | def set_level(self, level):
383 | self.level = level
384 |
385 | def set_comm(self, comm):
386 | self.comm = comm
387 |
388 | def get_dir(self):
389 | return self.dir
390 |
391 | def close(self):
392 | for fmt in self.output_formats:
393 | fmt.close()
394 |
395 | # Misc
396 | # ----------------------------------------
397 | def _do_log(self, args):
398 | for fmt in self.output_formats:
399 | if isinstance(fmt, SeqWriter):
400 | fmt.writeseq(map(str, args))
401 |
402 |
403 | def get_rank_without_mpi_import():
404 | # check environment variables here instead of importing mpi4py
405 | # to avoid calling MPI_Init() when this module is imported
406 | for varname in ["PMI_RANK", "OMPI_COMM_WORLD_RANK"]:
407 | if varname in os.environ:
408 | return int(os.environ[varname])
409 | return 0
410 |
411 |
412 | def mpi_weighted_mean(comm, local_name2valcount):
413 | """
414 | Copied from: https://github.com/openai/baselines/blob/ea25b9e8b234e6ee1bca43083f8f3cf974143998/baselines/common/mpi_util.py#L110
415 | Perform a weighted average over dicts that are each on a different node
416 | Input: local_name2valcount: dict mapping key -> (value, count)
417 | Returns: key -> mean
418 | """
419 | all_name2valcount = comm.gather(local_name2valcount)
420 | if comm.rank == 0:
421 | name2sum = defaultdict(float)
422 | name2count = defaultdict(float)
423 | for n2vc in all_name2valcount:
424 | for (name, (val, count)) in n2vc.items():
425 | try:
426 | val = float(val)
427 | except ValueError:
428 | if comm.rank == 0:
429 | warnings.warn(
430 | "WARNING: tried to compute mean on non-float {}={}".format(
431 | name, val
432 | )
433 | )
434 | else:
435 | name2sum[name] += val * count
436 | name2count[name] += count
437 | return {name: name2sum[name] / name2count[name] for name in name2sum}
438 | else:
439 | return {}
440 |
441 |
442 | def configure(dir=None, format_strs=None, comm=None, log_suffix=""):
443 | """
444 | If comm is provided, average all numerical stats across that comm
445 | """
446 | if dir is None:
447 | dir = os.getenv("OPENAI_LOGDIR")
448 | if dir is None:
449 | # dir = osp.join(
450 | # tempfile.gettempdir(),
451 | # datetime.datetime.now().strftime("openai-%Y-%m-%d-%H-%M-%S-%f"),
452 | # )
453 | dir = osp.join(
454 | "../experiment",
455 | datetime.datetime.now().strftime("openai-%Y-%m-%d-%H-%M-%S-%f"),
456 | )
457 | assert isinstance(dir, str)
458 | dir = os.path.expanduser(dir)
459 | os.makedirs(os.path.expanduser(dir), exist_ok=True)
460 |
461 | rank = get_rank_without_mpi_import()
462 | if rank > 0:
463 | log_suffix = log_suffix + "-rank%03i" % rank
464 |
465 | if format_strs is None:
466 | if rank == 0:
467 | format_strs = os.getenv("OPENAI_LOG_FORMAT", "stdout,log,csv").split(",")
468 | else:
469 | format_strs = os.getenv("OPENAI_LOG_FORMAT_MPI", "log").split(",")
470 | format_strs = filter(None, format_strs)
471 | output_formats = [make_output_format(f, dir, log_suffix) for f in format_strs]
472 |
473 | Logger.CURRENT = Logger(dir=dir, output_formats=output_formats, comm=comm)
474 | if output_formats:
475 | log("Logging to %s" % dir)
476 |
477 |
478 | def _configure_default_logger():
479 | configure()
480 | Logger.DEFAULT = Logger.CURRENT
481 |
482 |
483 | def reset():
484 | if Logger.CURRENT is not Logger.DEFAULT:
485 | Logger.CURRENT.close()
486 | Logger.CURRENT = Logger.DEFAULT
487 | log("Reset logger")
488 |
489 |
490 | @contextmanager
491 | def scoped_configure(dir=None, format_strs=None, comm=None):
492 | prevlogger = Logger.CURRENT
493 | configure(dir=dir, format_strs=format_strs, comm=comm)
494 | try:
495 | yield
496 | finally:
497 | Logger.CURRENT.close()
498 | Logger.CURRENT = prevlogger
499 |
500 |
--------------------------------------------------------------------------------
/cm/train_util.py:
--------------------------------------------------------------------------------
1 | import copy
2 | import functools
3 | import os
4 |
5 | import blobfile as bf
6 | import torch as th
7 | import torch.distributed as dist
8 | from torch.nn.parallel.distributed import DistributedDataParallel as DDP
9 | from torch.optim import RAdam, Adam
10 |
11 | from . import dist_util, logger
12 | from .fp16_util import MixedPrecisionTrainer
13 | from .nn import update_ema
14 | from .resample import LossAwareSampler, UniformSampler
15 |
16 | from .fp16_util import (
17 | get_param_groups_and_shapes,
18 | make_master_params,
19 | master_params_to_model_params,
20 | )
21 | import numpy as np
22 | import torchvision
23 | import time
24 | import datetime
25 | import copy
26 |
27 | # For ImageNet experiments, this was a good default value.
28 | # We found that the lg_loss_scale quickly climbed to
29 | # 20-21 within the first ~1K steps of training.
30 | INITIAL_LOG_LOSS_SCALE = 20.0
31 |
32 | def sec2str(seconds):
33 | days = seconds // (24 * 3600)
34 | seconds = seconds % (24 * 3600)
35 | hour = seconds // 3600
36 | seconds %= 3600
37 | minutes = seconds // 60
38 | seconds %= 60
39 |
40 | return "%d:%d:%02d:%02d" % (days, hour, minutes, seconds)
41 |
42 | class TrainLoop:
43 | def __init__(
44 | self,
45 | *,
46 | model,
47 | diffusion,
48 | data,
49 | batch_size,
50 | microbatch,
51 | lr,
52 | ema_rate,
53 | log_interval,
54 | save_interval,
55 | resume_checkpoint,
56 | use_fp16=False,
57 | fp16_scale_growth=1e-3,
58 | schedule_sampler=None,
59 | weight_decay=0.0,
60 | lr_anneal_steps=0,
61 | optimizer='radam',
62 | opt_eps=1e-8,
63 | ):
64 | self.model = model
65 | self.diffusion = diffusion
66 | self.data = data
67 | self.batch_size = batch_size
68 | self.microbatch = microbatch if microbatch > 0 else batch_size
69 | self.lr = lr
70 | self.ema_rate = (
71 | [ema_rate]
72 | if isinstance(ema_rate, float)
73 | else [float(x) for x in ema_rate.split(",")]
74 | )
75 | self.log_interval = log_interval
76 | self.save_interval = save_interval
77 | self.resume_checkpoint = resume_checkpoint
78 | self.use_fp16 = use_fp16
79 | self.fp16_scale_growth = fp16_scale_growth
80 | self.schedule_sampler = schedule_sampler or UniformSampler(diffusion)
81 | self.weight_decay = weight_decay
82 | self.lr_anneal_steps = lr_anneal_steps
83 |
84 | self.step = 0
85 | self.resume_step = 0
86 | self.global_batch = self.batch_size * dist.get_world_size()
87 |
88 | self.sync_cuda = th.cuda.is_available()
89 |
90 | self._load_and_sync_parameters()
91 | self.mp_trainer = MixedPrecisionTrainer(
92 | model=self.model,
93 | use_fp16=self.use_fp16,
94 | fp16_scale_growth=fp16_scale_growth,
95 | )
96 |
97 | training_params = self.mp_trainer.master_params
98 |
99 | if optimizer == 'radam':
100 | logger.log(f"use optimizer RAdam, lr: {self.lr}, weight_decay: {self.weight_decay}, eps: {opt_eps}")
101 | self.opt = RAdam(
102 | training_params , lr=self.lr, weight_decay=self.weight_decay, eps=opt_eps
103 | )
104 | elif optimizer == 'adam':
105 | logger.log(f"use optimizer Adam, lr: {self.lr}, weight_decay: {self.weight_decay}, eps: {opt_eps}")
106 | self.opt = Adam(
107 | training_params, lr=self.lr, weight_decay=self.weight_decay, eps=opt_eps
108 | )
109 | else:
110 | raise ValueError(f"Unsporrt optimizer {optimizer}")
111 |
112 | if self.resume_step:
113 | self._load_optimizer_state()
114 | # Model was resumed, either due to a restart or a checkpoint
115 | # being specified at the command line.
116 | self.ema_params = [
117 | self._load_ema_parameters(rate) for rate in self.ema_rate
118 | ]
119 | else:
120 | self.ema_params = [
121 | copy.deepcopy(self.mp_trainer.master_params)
122 | for _ in range(len(self.ema_rate))
123 | ]
124 |
125 | if th.cuda.is_available():
126 | self.use_ddp = True
127 | self.ddp_model = DDP(
128 | self.model,
129 | device_ids=[dist_util.dev()],
130 | output_device=dist_util.dev(),
131 | broadcast_buffers=False,
132 | bucket_cap_mb=128,
133 | find_unused_parameters=False,
134 | )
135 |
136 | else:
137 | if dist.get_world_size() > 1:
138 | logger.warn(
139 | "Distributed training requires CUDA. "
140 | "Gradients will not be synchronized properly!"
141 | )
142 | self.use_ddp = False
143 | self.ddp_model = self.model
144 |
145 | self.step = self.resume_step
146 |
147 | if dist.get_rank() == 0:
148 | code_save_dir = bf.join(get_blob_logdir(), "code")
149 | # try:
150 | import shutil
151 | shutil.copytree("./scripts", bf.join(code_save_dir, 'scripts') , dirs_exist_ok=True)
152 | shutil.copytree("./cm", bf.join(code_save_dir, 'cm') , dirs_exist_ok=True)
153 | logger.log(f"Save the code for current run in {code_save_dir}")
154 | # except Exception as err:
155 | # logger.log(f"Fail to save the code. {err}")
156 | # logger.log(f"Continue without saving the code...")
157 |
158 |
159 |
160 | def _load_and_sync_parameters(self):
161 | resume_checkpoint = find_resume_checkpoint() or self.resume_checkpoint
162 |
163 | if resume_checkpoint:
164 | self.resume_step = parse_resume_step_from_filename(resume_checkpoint)
165 | if dist.get_rank() == 0:
166 | logger.log(f"loading model from checkpoint: {resume_checkpoint}...")
167 | self.model.load_state_dict(
168 | dist_util.load_state_dict(
169 | resume_checkpoint, map_location=dist_util.dev()
170 | ),
171 | )
172 |
173 | dist_util.sync_params(self.model.parameters())
174 | dist_util.sync_params(self.model.buffers())
175 |
176 | def _load_ema_parameters(self, rate):
177 | ema_params = copy.deepcopy(self.mp_trainer.master_params)
178 |
179 | main_checkpoint = find_resume_checkpoint() or self.resume_checkpoint
180 | ema_checkpoint = find_ema_checkpoint(main_checkpoint, self.resume_step, rate)
181 | if ema_checkpoint:
182 | if dist.get_rank() == 0:
183 | logger.log(f"loading EMA from checkpoint: {ema_checkpoint}...")
184 | state_dict = dist_util.load_state_dict(
185 | ema_checkpoint, map_location=dist_util.dev()
186 | )
187 | ema_params = self.mp_trainer.state_dict_to_master_params(state_dict)
188 |
189 | dist_util.sync_params(ema_params)
190 | return ema_params
191 |
192 | def _load_optimizer_state(self):
193 | main_checkpoint = find_resume_checkpoint() or self.resume_checkpoint
194 | opt_checkpoint = bf.join(
195 | bf.dirname(main_checkpoint), f"opt{self.resume_step:06}.pt"
196 | )
197 | if bf.exists(opt_checkpoint):
198 | logger.log(f"loading optimizer state from checkpoint: {opt_checkpoint}")
199 | state_dict = dist_util.load_state_dict(
200 | opt_checkpoint, map_location=dist_util.dev()
201 | )
202 | self.opt.load_state_dict(state_dict)
203 |
204 | def run_loop(self):
205 | while not self.lr_anneal_steps or self.step < self.lr_anneal_steps:
206 | batch, cond = next(self.data)
207 | self.run_step(batch, cond)
208 | if self.step % self.log_interval == 0:
209 | logger.dumpkvs()
210 | if self.step % self.save_interval == 0:
211 | self.save()
212 | # Run for a finite amount of time in integration tests.
213 | if os.environ.get("DIFFUSION_TRAINING_TEST", "") and self.step > 0:
214 | return
215 | # Save the last checkpoint if it wasn't already saved.
216 | if (self.step - 1) % self.save_interval != 0:
217 | self.save()
218 |
219 | def run_step(self, batch, cond):
220 | self.forward_backward(batch, cond)
221 | took_step = self.mp_trainer.optimize(self.opt)
222 | if took_step:
223 | self.step += 1
224 | self._update_ema()
225 | self._anneal_lr()
226 | self.log_step()
227 |
228 | def forward_backward(self, batch, cond):
229 | self.mp_trainer.zero_grad()
230 | for i in range(0, batch.shape[0], self.microbatch):
231 | micro = batch[i : i + self.microbatch].to(dist_util.dev())
232 | micro_cond = {
233 | k: v[i : i + self.microbatch].to(dist_util.dev())
234 | for k, v in cond.items()
235 | }
236 | last_batch = (i + self.microbatch) >= batch.shape[0]
237 | t, weights = self.schedule_sampler.sample(micro.shape[0], dist_util.dev())
238 |
239 | compute_losses = functools.partial(
240 | self.diffusion.training_losses,
241 | self.ddp_model,
242 | micro,
243 | t,
244 | model_kwargs=micro_cond,
245 | )
246 |
247 | if last_batch or not self.use_ddp:
248 | losses = compute_losses()
249 | else:
250 | with self.ddp_model.no_sync():
251 | losses = compute_losses()
252 |
253 | if isinstance(self.schedule_sampler, LossAwareSampler):
254 | self.schedule_sampler.update_with_local_losses(
255 | t, losses["loss"].detach()
256 | )
257 |
258 | loss = (losses["loss"] * weights).mean()
259 | log_loss_dict(
260 | self.diffusion, t, {k: v * weights for k, v in losses.items()}
261 | )
262 | self.mp_trainer.backward(loss)
263 |
264 | def _update_ema(self):
265 | for rate, params in zip(self.ema_rate, self.ema_params):
266 | update_ema(params, self.mp_trainer.master_params, rate=rate)
267 |
268 |
269 | def _anneal_lr(self):
270 | if not self.lr_anneal_steps:
271 | return
272 | frac_done = (self.step + self.resume_step) / self.lr_anneal_steps
273 | lr = self.lr * (1 - frac_done)
274 | for param_group in self.opt.param_groups:
275 | param_group["lr"] = lr
276 |
277 | def log_step(self):
278 | logger.logkv("step", self.step + self.resume_step)
279 | logger.logkv("samples", (self.step + self.resume_step + 1) * self.global_batch)
280 |
281 | def save(self):
282 | def save_checkpoint(rate, params):
283 | state_dict = self.mp_trainer.master_params_to_state_dict(params)
284 | if dist.get_rank() == 0:
285 | logger.log(f"saving model {rate}...")
286 | if not rate:
287 | filename = f"model{(self.step+self.resume_step):06d}.pt"
288 | else:
289 | filename = f"ema_{rate}_{(self.step+self.resume_step):06d}.pt"
290 | with bf.BlobFile(bf.join(get_blob_logdir(), filename), "wb") as f:
291 | th.save(state_dict, f)
292 |
293 | for rate, params in zip(self.ema_rate, self.ema_params):
294 | save_checkpoint(rate, params)
295 |
296 | if dist.get_rank() == 0:
297 | with bf.BlobFile(
298 | bf.join(get_blob_logdir(), f"opt{(self.step+self.resume_step):06d}.pt"),
299 | "wb",
300 | ) as f:
301 | th.save(self.opt.state_dict(), f)
302 |
303 | # Save model parameters last to prevent race conditions where a restart
304 | # loads model at step N, but opt/ema state isn't saved for step N.
305 | save_checkpoint(0, self.mp_trainer.master_params)
306 | dist.barrier()
307 |
308 |
309 |
310 | class ODETrainLoop(TrainLoop):
311 | def __init__(
312 | self,
313 | *,
314 | teacher_model,
315 | teacher_diffusion,
316 | training_mode,
317 | ema_scale_fn,
318 | total_training_steps,
319 | methodology,
320 | eval_interval,
321 | **kwargs,
322 | ):
323 | super().__init__(**kwargs)
324 | self.training_mode = training_mode
325 | self.ema_scale_fn = ema_scale_fn
326 | self.teacher_model = teacher_model
327 | self.teacher_diffusion = teacher_diffusion
328 | self.total_training_steps = total_training_steps
329 | self.methodology = methodology
330 | self.eval_interval = eval_interval
331 |
332 |
333 |
334 | if teacher_model:
335 | self._load_and_sync_teacher_parameters()
336 | self.teacher_model.requires_grad_(False)
337 | self.teacher_model.eval()
338 | for param in self.teacher_model.parameters():
339 | param.requires_grad_(False)
340 |
341 | self.global_step = self.step
342 | if training_mode == "progdist":
343 | _, scale = ema_scale_fn(self.global_step)
344 | if scale == 1 or scale == 2:
345 | _, start_scale = ema_scale_fn(0)
346 | n_normal_steps = int(np.log2(start_scale // 2)) * self.lr_anneal_steps
347 | step = self.global_step - n_normal_steps
348 | if step != 0:
349 | self.lr_anneal_steps *= 2
350 | self.step = step % self.lr_anneal_steps
351 | else:
352 | self.step = 0
353 | else:
354 | self.step = self.global_step % self.lr_anneal_steps
355 |
356 |
357 |
358 | def _load_and_sync_teacher_parameters(self):
359 | resume_checkpoint = find_resume_checkpoint() or self.resume_checkpoint
360 | if resume_checkpoint:
361 | path, name = os.path.split(resume_checkpoint)
362 | teacher_name = name.replace("model", "teacher_model")
363 | resume_teacher_checkpoint = os.path.join(path, teacher_name)
364 |
365 | if bf.exists(resume_teacher_checkpoint) and dist.get_rank() == 0:
366 | logger.log(
367 | "loading model from checkpoint: {resume_teacher_checkpoint}..."
368 | )
369 | self.teacher_model.load_state_dict(
370 | dist_util.load_state_dict(
371 | resume_teacher_checkpoint, map_location=dist_util.dev()
372 | ),
373 | )
374 |
375 | dist_util.sync_params(self.teacher_model.parameters())
376 | dist_util.sync_params(self.teacher_model.buffers())
377 |
378 | def run_loop(self):
379 | saved = False
380 | from cm.unet import UNetModel
381 | self.model: UNetModel
382 | self.image_size = (self.model.in_channels, self.model.image_size, self.model.image_size)
383 | tic_time = time.time()
384 | begining_time = time.time()
385 |
386 | while (
387 | not self.lr_anneal_steps
388 | or self.step < self.lr_anneal_steps
389 | or self.global_step < self.total_training_steps
390 | ):
391 |
392 | device = dist_util.dev()
393 |
394 | ##########################################################################
395 | # random noise
396 | ##########################################################################
397 | init_condition = th.randn((self.batch_size, *self.image_size), device=device)
398 | training_class_labels = None
399 | if self.model.num_classes is not None:
400 | training_class_labels = th.randint(0, self.model.num_classes, (self.batch_size,), device=device)
401 |
402 | ##########################################################################
403 |
404 | # construct the dataset
405 |
406 | batch = {
407 | "noise": init_condition * 80.,
408 | }
409 | cond = {
410 | "noise_cond":training_class_labels,
411 | }
412 |
413 | self.run_step(batch, cond)
414 | saved = False
415 | if (
416 | self.global_step
417 | and self.save_interval != -1
418 | and self.global_step % self.save_interval == 0
419 | ):
420 | self.save()
421 | saved = True
422 | th.cuda.empty_cache()
423 | # Run for a finite amount of time in integration tests.
424 | if os.environ.get("DIFFUSION_TRAINING_TEST", "") and self.step > 0:
425 | return
426 |
427 | if self.global_step % self.log_interval == 0:
428 | logger.dumpkvs()
429 |
430 | if dist.get_rank() == 0:
431 | current_time = datetime.datetime.now()
432 | t_dur = time.time() - tic_time
433 | t_spend = time.time() - begining_time
434 | t_eta = t_dur*((self.total_training_steps-self.global_step)//(self.log_interval))
435 | t_total = t_eta + t_spend
436 |
437 | logger.log(f"{t_dur} s/10iter at {current_time}. ETA: {sec2str(t_eta)}, Spend: {sec2str(t_spend)}, Total: {sec2str(t_total)}")
438 |
439 | tic_time = time.time()
440 |
441 | # Save the last checkpoint if it wasn't already saved.
442 | if not saved:
443 | self.save()
444 |
445 |
446 | def run_step(self, batch, cond):
447 | self.forward_backward(batch, cond)
448 | took_step = self.mp_trainer.optimize(self.opt)
449 | if took_step:
450 | self._update_ema()
451 |
452 | self.step += 1
453 | self.global_step += 1
454 |
455 | self._anneal_lr()
456 | self.log_step()
457 |
458 |
459 |
460 |
461 | def forward_backward(self, batch, cond):
462 | self.mp_trainer.zero_grad()
463 | batch_size = batch['noise'].shape[0]
464 | for i in range(0, batch_size, self.microbatch):
465 | micro = {}
466 | for k, v in batch.items():
467 | micro[k] = v[i : i + self.microbatch].to(dist_util.dev())
468 |
469 | micro_cond = None
470 | if self.model.num_classes:
471 | if self.training_mode in ["one_shot_pinn_edm_edm_randominit"]:
472 | micro_cond = {
473 | "noise_cond": cond["noise_cond"][i : i + self.microbatch].to(dist_util.dev()),
474 | "img_cond": cond["img_cond"][i : i + self.microbatch].to(dist_util.dev()),
475 | }
476 | else:
477 | micro_cond = {"noise_cond": cond["noise_cond"][i : i + self.microbatch].to(dist_util.dev())}
478 |
479 |
480 | last_batch = (i + self.microbatch) >= batch_size
481 | t, weights = self.schedule_sampler.sample(micro['noise'].shape[0], dist_util.dev())
482 |
483 | ema, num_scales = self.ema_scale_fn(self.global_step)
484 |
485 | compute_losses = functools.partial(
486 | self.diffusion.ode_losses,
487 | self.ddp_model,
488 | micro,
489 | num_scales,
490 | teacher_model=self.teacher_model,
491 | teacher_diffusion=self.teacher_diffusion,
492 | model_kwargs=micro_cond,
493 | current_step=self.global_step,
494 | )
495 |
496 | if last_batch or not self.use_ddp:
497 | losses = compute_losses()
498 | else:
499 | with self.ddp_model.no_sync():
500 | losses = compute_losses()
501 |
502 | if isinstance(self.schedule_sampler, LossAwareSampler):
503 | self.schedule_sampler.update_with_local_losses(
504 | t, losses["loss"].detach()
505 | )
506 |
507 | loss = (losses["loss"]).mean()
508 |
509 | log_loss_dict(
510 | self.diffusion, t, {k: v for k, v in losses.items()}
511 | )
512 | self.mp_trainer.backward(loss)
513 |
514 | def save(self):
515 | import blobfile as bf
516 |
517 | step = self.global_step
518 |
519 | def save_checkpoint(rate, params):
520 | state_dict = self.mp_trainer.master_params_to_state_dict(params)
521 | if dist.get_rank() == 0:
522 | logger.log(f"saving model {rate}...")
523 | if not rate:
524 | filename = f"model{step:06d}.pt"
525 | else:
526 | filename = f"ema_{rate}_{step:06d}.pt"
527 | with bf.BlobFile(bf.join(get_blob_logdir(), filename), "wb") as f:
528 | th.save(state_dict, f)
529 |
530 | for rate, params in zip(self.ema_rate, self.ema_params):
531 | save_checkpoint(rate, params)
532 |
533 | logger.log("saving optimizer state...")
534 | if dist.get_rank() == 0:
535 | with bf.BlobFile(
536 | bf.join(get_blob_logdir(), f"opt{step:06d}.pt"),
537 | "wb",
538 | ) as f:
539 | th.save(self.opt.state_dict(), f)
540 |
541 | if dist.get_rank() == 0:
542 |
543 | if self.teacher_model and self.training_mode == "progdist":
544 | logger.log("saving teacher model state")
545 | filename = f"teacher_model{step:06d}.pt"
546 | with bf.BlobFile(bf.join(get_blob_logdir(), filename), "wb") as f:
547 | th.save(self.teacher_model.state_dict(), f)
548 |
549 | # Save model parameters last to prevent race conditions where a restart
550 | # loads model at step N, but opt/ema state isn't saved for step N.
551 | save_checkpoint(0, self.mp_trainer.master_params)
552 |
553 | dist.barrier()
554 |
555 | def log_step(self):
556 | step = self.global_step
557 | logger.logkv("step", step)
558 | logger.logkv("samples", (step + 1) * self.global_batch)
559 |
560 |
561 |
562 | def parse_resume_step_from_filename(filename):
563 | """
564 | Parse filenames of the form path/to/modelNNNNNN.pt, where NNNNNN is the
565 | checkpoint's number of steps.
566 | """
567 | split = filename.split("model")
568 | if len(split) < 2:
569 | return 0
570 | split1 = split[-1].split(".")[0]
571 | try:
572 | return int(split1)
573 | except ValueError:
574 | return 0
575 |
576 |
577 | def get_blob_logdir():
578 | # You can change this to be a separate path to save checkpoints to
579 | # a blobstore or some external drive.
580 | return logger.get_dir()
581 |
582 |
583 | def find_resume_checkpoint():
584 | # On your infrastructure, you may want to override this to automatically
585 | # discover the latest checkpoint on your blob storage, etc.
586 | return None
587 |
588 |
589 | def find_ema_checkpoint(main_checkpoint, step, rate):
590 | if main_checkpoint is None:
591 | return None
592 | filename = f"ema_{rate}_{(step):06d}.pt"
593 | path = bf.join(bf.dirname(main_checkpoint), filename)
594 | if bf.exists(path):
595 | return path
596 | return None
597 |
598 |
599 | def log_loss_dict(diffusion, ts, losses):
600 | for key, values in losses.items():
601 | logger.logkv_mean(key, values.mean().item())
602 | # Log the quantiles (four quartiles, in particular).
603 | for sub_t, sub_loss in zip(ts.cpu().numpy(), values.detach().cpu().numpy()):
604 | quartile = int(4 * sub_t / diffusion.num_timesteps)
605 | logger.logkv_mean(f"{key}_q{quartile}", sub_loss)
606 |
--------------------------------------------------------------------------------
/cm/unet.py:
--------------------------------------------------------------------------------
1 | from abc import abstractmethod
2 |
3 | import math
4 |
5 | import numpy as np
6 | import torch as th
7 | import torch.nn as nn
8 | import torch.nn.functional as F
9 |
10 | from .fp16_util import convert_module_to_f16, convert_module_to_f32
11 | from .nn import (
12 | checkpoint,
13 | conv_nd,
14 | linear,
15 | avg_pool_nd,
16 | zero_module,
17 | normalization,
18 | timestep_embedding,
19 | )
20 |
21 |
22 | class AttentionPool2d(nn.Module):
23 | """
24 | Adapted from CLIP: https://github.com/openai/CLIP/blob/main/clip/model.py
25 | """
26 |
27 | def __init__(
28 | self,
29 | spacial_dim: int,
30 | embed_dim: int,
31 | num_heads_channels: int,
32 | output_dim: int = None,
33 | ):
34 | super().__init__()
35 | self.positional_embedding = nn.Parameter(
36 | th.randn(embed_dim, spacial_dim**2 + 1) / embed_dim**0.5
37 | )
38 | self.qkv_proj = conv_nd(1, embed_dim, 3 * embed_dim, 1)
39 | self.c_proj = conv_nd(1, embed_dim, output_dim or embed_dim, 1)
40 | self.num_heads = embed_dim // num_heads_channels
41 | self.attention = QKVAttention(self.num_heads)
42 |
43 | def forward(self, x):
44 | b, c, *_spatial = x.shape
45 | x = x.reshape(b, c, -1) # NC(HW)
46 | x = th.cat([x.mean(dim=-1, keepdim=True), x], dim=-1) # NC(HW+1)
47 | x = x + self.positional_embedding[None, :, :].to(x.dtype) # NC(HW+1)
48 | x = self.qkv_proj(x)
49 | x = self.attention(x)
50 | x = self.c_proj(x)
51 | return x[:, :, 0]
52 |
53 |
54 | class TimestepBlock(nn.Module):
55 | """
56 | Any module where forward() takes timestep embeddings as a second argument.
57 | """
58 |
59 | @abstractmethod
60 | def forward(self, x, emb):
61 | """
62 | Apply the module to `x` given `emb` timestep embeddings.
63 | """
64 |
65 |
66 | class TimestepEmbedSequential(nn.Sequential, TimestepBlock):
67 | """
68 | A sequential module that passes timestep embeddings to the children that
69 | support it as an extra input.
70 | """
71 |
72 | def forward(self, x, emb):
73 | for layer in self:
74 | if isinstance(layer, TimestepBlock):
75 | x = layer(x, emb)
76 | else:
77 | x = layer(x)
78 | return x
79 |
80 |
81 | class Upsample(nn.Module):
82 | """
83 | An upsampling layer with an optional convolution.
84 |
85 | :param channels: channels in the inputs and outputs.
86 | :param use_conv: a bool determining if a convolution is applied.
87 | :param dims: determines if the signal is 1D, 2D, or 3D. If 3D, then
88 | upsampling occurs in the inner-two dimensions.
89 | """
90 |
91 | def __init__(self, channels, use_conv, dims=2, out_channels=None):
92 | super().__init__()
93 | self.channels = channels
94 | self.out_channels = out_channels or channels
95 | self.use_conv = use_conv
96 | self.dims = dims
97 | if use_conv:
98 | self.conv = conv_nd(dims, self.channels, self.out_channels, 3, padding=1)
99 |
100 | def forward(self, x):
101 | assert x.shape[1] == self.channels
102 | if self.dims == 3:
103 | x = F.interpolate(
104 | x, (x.shape[2], x.shape[3] * 2, x.shape[4] * 2), mode="nearest"
105 | )
106 | else:
107 | x = F.interpolate(x, scale_factor=2, mode="nearest")
108 | if self.use_conv:
109 | x = self.conv(x)
110 | return x
111 |
112 |
113 | class Downsample(nn.Module):
114 | """
115 | A downsampling layer with an optional convolution.
116 |
117 | :param channels: channels in the inputs and outputs.
118 | :param use_conv: a bool determining if a convolution is applied.
119 | :param dims: determines if the signal is 1D, 2D, or 3D. If 3D, then
120 | downsampling occurs in the inner-two dimensions.
121 | """
122 |
123 | def __init__(self, channels, use_conv, dims=2, out_channels=None):
124 | super().__init__()
125 | self.channels = channels
126 | self.out_channels = out_channels or channels
127 | self.use_conv = use_conv
128 | self.dims = dims
129 | stride = 2 if dims != 3 else (1, 2, 2)
130 | if use_conv:
131 | self.op = conv_nd(
132 | dims, self.channels, self.out_channels, 3, stride=stride, padding=1
133 | )
134 | else:
135 | assert self.channels == self.out_channels
136 | self.op = avg_pool_nd(dims, kernel_size=stride, stride=stride)
137 |
138 | def forward(self, x):
139 | assert x.shape[1] == self.channels
140 | return self.op(x)
141 |
142 |
143 | class ResBlock(TimestepBlock):
144 | """
145 | A residual block that can optionally change the number of channels.
146 |
147 | :param channels: the number of input channels.
148 | :param emb_channels: the number of timestep embedding channels.
149 | :param dropout: the rate of dropout.
150 | :param out_channels: if specified, the number of out channels.
151 | :param use_conv: if True and out_channels is specified, use a spatial
152 | convolution instead of a smaller 1x1 convolution to change the
153 | channels in the skip connection.
154 | :param dims: determines if the signal is 1D, 2D, or 3D.
155 | :param use_checkpoint: if True, use gradient checkpointing on this module.
156 | :param up: if True, use this block for upsampling.
157 | :param down: if True, use this block for downsampling.
158 | """
159 |
160 | def __init__(
161 | self,
162 | channels,
163 | emb_channels,
164 | dropout,
165 | out_channels=None,
166 | use_conv=False,
167 | use_scale_shift_norm=False,
168 | dims=2,
169 | use_checkpoint=False,
170 | up=False,
171 | down=False,
172 | ):
173 | super().__init__()
174 | self.channels = channels
175 | self.emb_channels = emb_channels
176 | self.dropout = dropout
177 | self.out_channels = out_channels or channels
178 | self.use_conv = use_conv
179 | self.use_checkpoint = use_checkpoint
180 | self.use_scale_shift_norm = use_scale_shift_norm
181 |
182 | self.in_layers = nn.Sequential(
183 | normalization(channels),
184 | nn.SiLU(),
185 | conv_nd(dims, channels, self.out_channels, 3, padding=1),
186 | )
187 |
188 | self.updown = up or down
189 |
190 | if up:
191 | self.h_upd = Upsample(channels, False, dims)
192 | self.x_upd = Upsample(channels, False, dims)
193 | elif down:
194 | self.h_upd = Downsample(channels, False, dims)
195 | self.x_upd = Downsample(channels, False, dims)
196 | else:
197 | self.h_upd = self.x_upd = nn.Identity()
198 |
199 | self.emb_layers = nn.Sequential(
200 | nn.SiLU(),
201 | linear(
202 | emb_channels,
203 | 2 * self.out_channels if use_scale_shift_norm else self.out_channels,
204 | ),
205 | )
206 | self.out_layers = nn.Sequential(
207 | normalization(self.out_channels),
208 | nn.SiLU(),
209 | nn.Dropout(p=dropout),
210 | zero_module(
211 | conv_nd(dims, self.out_channels, self.out_channels, 3, padding=1)
212 | ),
213 | )
214 |
215 | if self.out_channels == channels:
216 | self.skip_connection = nn.Identity()
217 | elif use_conv:
218 | self.skip_connection = conv_nd(
219 | dims, channels, self.out_channels, 3, padding=1
220 | )
221 | else:
222 | self.skip_connection = conv_nd(dims, channels, self.out_channels, 1)
223 |
224 | def forward(self, x, emb):
225 | """
226 | Apply the block to a Tensor, conditioned on a timestep embedding.
227 |
228 | :param x: an [N x C x ...] Tensor of features.
229 | :param emb: an [N x emb_channels] Tensor of timestep embeddings.
230 | :return: an [N x C x ...] Tensor of outputs.
231 | """
232 | return checkpoint(
233 | self._forward, (x, emb), self.parameters(), self.use_checkpoint
234 | )
235 |
236 | def _forward(self, x, emb):
237 | if self.updown:
238 | in_rest, in_conv = self.in_layers[:-1], self.in_layers[-1]
239 | h = in_rest(x)
240 | h = self.h_upd(h)
241 | x = self.x_upd(x)
242 | h = in_conv(h)
243 | else:
244 | h = self.in_layers(x)
245 | emb_out = self.emb_layers(emb).type(h.dtype)
246 | while len(emb_out.shape) < len(h.shape):
247 | emb_out = emb_out[..., None]
248 | if self.use_scale_shift_norm:
249 | out_norm, out_rest = self.out_layers[0], self.out_layers[1:]
250 | scale, shift = th.chunk(emb_out, 2, dim=1)
251 | h = out_norm(h) * (1 + scale) + shift
252 | h = out_rest(h)
253 | else:
254 | h = h + emb_out
255 | h = self.out_layers(h)
256 | return self.skip_connection(x) + h
257 |
258 |
259 | class AttentionBlock(nn.Module):
260 | """
261 | An attention block that allows spatial positions to attend to each other.
262 |
263 | Originally ported from here, but adapted to the N-d case.
264 | https://github.com/hojonathanho/diffusion/blob/1e0dceb3b3495bbe19116a5e1b3596cd0706c543/diffusion_tf/models/unet.py#L66.
265 | """
266 |
267 | def __init__(
268 | self,
269 | channels,
270 | num_heads=1,
271 | num_head_channels=-1,
272 | use_checkpoint=False,
273 | attention_type="flash",
274 | # attention_type="normal",
275 | encoder_channels=None,
276 | dims=2,
277 | channels_last=False,
278 | use_new_attention_order=False,
279 | ):
280 | super().__init__()
281 | self.channels = channels
282 | if num_head_channels == -1:
283 | self.num_heads = num_heads
284 | else:
285 | assert (
286 | channels % num_head_channels == 0
287 | ), f"q,k,v channels {channels} is not divisible by num_head_channels {num_head_channels}"
288 | self.num_heads = channels // num_head_channels
289 | self.use_checkpoint = use_checkpoint
290 | self.norm = normalization(channels)
291 | self.qkv = conv_nd(dims, channels, channels * 3, 1)
292 | self.attention_type = attention_type
293 | if attention_type == "flash":
294 | self.attention = QKVFlashAttention(channels, self.num_heads)
295 | else:
296 | # split heads before split qkv
297 | self.attention = QKVAttentionLegacy(self.num_heads)
298 |
299 | self.use_attention_checkpoint = not (
300 | self.use_checkpoint or self.attention_type == "flash"
301 | )
302 | if encoder_channels is not None:
303 | assert attention_type != "flash"
304 | self.encoder_kv = conv_nd(1, encoder_channels, channels * 2, 1)
305 | self.proj_out = zero_module(conv_nd(dims, channels, channels, 1))
306 |
307 | def forward(self, x, encoder_out=None):
308 | if encoder_out is None:
309 | return checkpoint(
310 | self._forward, (x,), self.parameters(), self.use_checkpoint
311 | )
312 | else:
313 | return checkpoint(
314 | self._forward, (x, encoder_out), self.parameters(), self.use_checkpoint
315 | )
316 |
317 | def _forward(self, x, encoder_out=None):
318 | b, _, *spatial = x.shape
319 | qkv = self.qkv(self.norm(x)).view(b, -1, np.prod(spatial))
320 | if encoder_out is not None:
321 | encoder_out = self.encoder_kv(encoder_out)
322 | h = checkpoint(
323 | self.attention, (qkv, encoder_out), (), self.use_attention_checkpoint
324 | )
325 | else:
326 | h = checkpoint(self.attention, (qkv,), (), self.use_attention_checkpoint)
327 | h = h.view(b, -1, *spatial)
328 | h = self.proj_out(h)
329 | return x + h
330 |
331 |
332 | class QKVFlashAttention(nn.Module):
333 | def __init__(
334 | self,
335 | embed_dim,
336 | num_heads,
337 | batch_first=True,
338 | attention_dropout=0.0,
339 | causal=False,
340 | device=None,
341 | dtype=None,
342 | **kwargs,
343 | ) -> None:
344 | from einops import rearrange
345 | # from flash_attn.flash_attention import FlashAttention
346 | from flash_attn import flash_attn_qkvpacked_func
347 |
348 | assert batch_first
349 | factory_kwargs = {"device": device, "dtype": dtype}
350 | super().__init__()
351 | self.embed_dim = embed_dim
352 | self.num_heads = num_heads
353 | self.causal = causal
354 |
355 | assert (
356 | self.embed_dim % num_heads == 0
357 | ), "self.kdim must be divisible by num_heads"
358 | self.head_dim = self.embed_dim // num_heads
359 | assert self.head_dim in [16, 32, 64], "Only support head_dim == 16, 32, or 64"
360 |
361 | # self.inner_attn = FlashAttention(
362 | # attention_dropout=attention_dropout
363 | # )
364 | self.attention_dropout = attention_dropout
365 | self.inner_attn = flash_attn_qkvpacked_func
366 | self.rearrange = rearrange
367 |
368 | def forward(self, qkv, attn_mask=None, key_padding_mask=None, need_weights=False):
369 | qkv = self.rearrange(
370 | qkv, "b (three h d) s -> b s three h d", three=3, h=self.num_heads
371 | ).contiguous()
372 | # qkv, _ = self.inner_attn(
373 | # qkv,
374 | # key_padding_mask=key_padding_mask,
375 | # need_weights=need_weights,
376 | # causal=self.causal,
377 | # )
378 | attention_dropout = 0.0
379 | if self.training:
380 | attention_dropout = self.attention_dropout
381 | qkv = self.inner_attn(qkv, attention_dropout)
382 | return self.rearrange(qkv, "b s h d -> b (h d) s")
383 |
384 |
385 | def count_flops_attn(model, _x, y):
386 | """
387 | A counter for the `thop` package to count the operations in an
388 | attention operation.
389 | Meant to be used like:
390 | macs, params = thop.profile(
391 | model,
392 | inputs=(inputs, timestamps),
393 | custom_ops={QKVAttention: QKVAttention.count_flops},
394 | )
395 | """
396 | b, c, *spatial = y[0].shape
397 | num_spatial = int(np.prod(spatial))
398 | # We perform two matmuls with the same number of ops.
399 | # The first computes the weight matrix, the second computes
400 | # the combination of the value vectors.
401 | matmul_ops = 2 * b * (num_spatial**2) * c
402 | model.total_ops += th.DoubleTensor([matmul_ops])
403 |
404 |
405 | class QKVAttentionLegacy(nn.Module):
406 | """
407 | A module which performs QKV attention. Matches legacy QKVAttention + input/ouput heads shaping
408 | """
409 |
410 | def __init__(self, n_heads):
411 | super().__init__()
412 | from einops import rearrange
413 | self.n_heads = n_heads
414 | self.rearrange = rearrange
415 |
416 | def forward(self, qkv):
417 | """
418 | Apply QKV attention.
419 |
420 | :param qkv: an [N x (H * 3 * C) x T] tensor of Qs, Ks, and Vs.
421 | :return: an [N x (H * C) x T] tensor after attention.
422 | """
423 | bs, width, length = qkv.shape
424 | assert width % (3 * self.n_heads) == 0
425 | ch = width // (3 * self.n_heads)
426 | q, k, v = self.rearrange(
427 | qkv, "b (three h d) s -> (b h) (three d) s", three=3, h=self.n_heads
428 | ).contiguous().split(ch, dim=1)
429 |
430 | # q, k, v = qkv.reshape(bs * self.n_heads, ch * 3, length).split(ch, dim=1)
431 | scale = 1 / math.sqrt(math.sqrt(ch))
432 | weight = th.einsum(
433 | "bct,bcs->bts", q * scale, k * scale
434 | ) # More stable with f16 than dividing afterwards
435 | weight = th.softmax(weight.float(), dim=-1).type(weight.dtype)
436 | a = th.einsum("bts,bcs->bct", weight, v)
437 | return a.reshape(bs, -1, length)
438 |
439 | @staticmethod
440 | def count_flops(model, _x, y):
441 | return count_flops_attn(model, _x, y)
442 |
443 |
444 | # class QKVAttention(nn.Module):
445 | # """
446 | # A module which performs QKV attention and splits in a different order.
447 | # """
448 |
449 | # def __init__(self, n_heads):
450 | # super().__init__()
451 | # self.n_heads = n_heads
452 |
453 | # def forward(self, qkv):
454 | # """
455 | # Apply QKV attention.
456 |
457 | # :param qkv: an [N x (3 * H * C) x T] tensor of Qs, Ks, and Vs.
458 | # :return: an [N x (H * C) x T] tensor after attention.
459 | # """
460 | # bs, width, length = qkv.shape
461 | # assert width % (3 * self.n_heads) == 0
462 | # ch = width // (3 * self.n_heads)
463 | # q, k, v = qkv.chunk(3, dim=1)
464 | # scale = 1 / math.sqrt(math.sqrt(ch))
465 | # weight = th.einsum(
466 | # "bct,bcs->bts",
467 | # (q * scale).view(bs * self.n_heads, ch, length),
468 | # (k * scale).view(bs * self.n_heads, ch, length),
469 | # ) # More stable with f16 than dividing afterwards
470 | # weight = th.softmax(weight.float(), dim=-1).type(weight.dtype)
471 | # a = th.einsum("bts,bcs->bct", weight, v.reshape(bs * self.n_heads, ch, length))
472 | # return a.reshape(bs, -1, length)
473 |
474 | # @staticmethod
475 | # def count_flops(model, _x, y):
476 | # return count_flops_attn(model, _x, y)
477 |
478 |
479 | class QKVAttention(nn.Module):
480 | """
481 | A module which performs QKV attention. Fallback from Blocksparse if use_fp16=False
482 | """
483 |
484 | def __init__(self, n_heads):
485 | super().__init__()
486 | self.n_heads = n_heads
487 |
488 | def forward(self, qkv, encoder_kv=None):
489 | """
490 | Apply QKV attention.
491 |
492 | :param qkv: an [N x (3 * H * C) x T] tensor of Qs, Ks, and Vs.
493 | :return: an [N x (H * C) x T] tensor after attention.
494 | """
495 | bs, width, length = qkv.shape
496 | assert width % (3 * self.n_heads) == 0
497 | ch = width // (3 * self.n_heads)
498 | q, k, v = qkv.chunk(3, dim=1)
499 | if encoder_kv is not None:
500 | assert encoder_kv.shape[1] == 2 * ch * self.n_heads
501 | ek, ev = encoder_kv.chunk(2, dim=1)
502 | k = th.cat([ek, k], dim=-1)
503 | v = th.cat([ev, v], dim=-1)
504 | scale = 1 / math.sqrt(math.sqrt(ch))
505 | weight = th.einsum(
506 | "bct,bcs->bts",
507 | (q * scale).view(bs * self.n_heads, ch, length),
508 | (k * scale).view(bs * self.n_heads, ch, -1),
509 | ) # More stable with f16 than dividing afterwards
510 | weight = th.softmax(weight.float(), dim=-1).type(weight.dtype)
511 | a = th.einsum("bts,bcs->bct", weight, v.reshape(bs * self.n_heads, ch, -1))
512 | return a.reshape(bs, -1, length)
513 |
514 | @staticmethod
515 | def count_flops(model, _x, y):
516 | return count_flops_attn(model, _x, y)
517 |
518 |
519 | class UNetModel(nn.Module):
520 | """
521 | The full UNet model with attention and timestep embedding.
522 |
523 | :param in_channels: channels in the input Tensor.
524 | :param model_channels: base channel count for the model.
525 | :param out_channels: channels in the output Tensor.
526 | :param num_res_blocks: number of residual blocks per downsample.
527 | :param attention_resolutions: a collection of downsample rates at which
528 | attention will take place. May be a set, list, or tuple.
529 | For example, if this contains 4, then at 4x downsampling, attention
530 | will be used.
531 | :param dropout: the dropout probability.
532 | :param channel_mult: channel multiplier for each level of the UNet.
533 | :param conv_resample: if True, use learned convolutions for upsampling and
534 | downsampling.
535 | :param dims: determines if the signal is 1D, 2D, or 3D.
536 | :param num_classes: if specified (as an int), then this model will be
537 | class-conditional with `num_classes` classes.
538 | :param use_checkpoint: use gradient checkpointing to reduce memory usage.
539 | :param num_heads: the number of attention heads in each attention layer.
540 | :param num_heads_channels: if specified, ignore num_heads and instead use
541 | a fixed channel width per attention head.
542 | :param num_heads_upsample: works with num_heads to set a different number
543 | of heads for upsampling. Deprecated.
544 | :param use_scale_shift_norm: use a FiLM-like conditioning mechanism.
545 | :param resblock_updown: use residual blocks for up/downsampling.
546 | :param use_new_attention_order: use a different attention pattern for potentially
547 | increased efficiency.
548 | """
549 |
550 | def __init__(
551 | self,
552 | image_size,
553 | in_channels,
554 | model_channels,
555 | out_channels,
556 | num_res_blocks,
557 | attention_resolutions,
558 | dropout=0,
559 | channel_mult=(1, 2, 4, 8),
560 | conv_resample=True,
561 | dims=2,
562 | num_classes=None,
563 | use_checkpoint=False,
564 | use_fp16=False,
565 | num_heads=1,
566 | num_head_channels=-1,
567 | num_heads_upsample=-1,
568 | use_scale_shift_norm=False,
569 | resblock_updown=False,
570 | use_new_attention_order=False,
571 | ):
572 | super().__init__()
573 |
574 | if num_heads_upsample == -1:
575 | num_heads_upsample = num_heads
576 |
577 | self.image_size = image_size
578 | self.in_channels = in_channels
579 | self.model_channels = model_channels
580 | self.out_channels = out_channels
581 | self.num_res_blocks = num_res_blocks
582 | self.attention_resolutions = attention_resolutions
583 | self.dropout = dropout
584 | self.channel_mult = channel_mult
585 | self.conv_resample = conv_resample
586 | self.num_classes = num_classes
587 | self.use_checkpoint = use_checkpoint
588 | self.dtype = th.float16 if use_fp16 else th.float32
589 | self.num_heads = num_heads
590 | self.num_head_channels = num_head_channels
591 | self.num_heads_upsample = num_heads_upsample
592 |
593 | time_embed_dim = model_channels * 4
594 | self.time_embed = nn.Sequential(
595 | linear(model_channels, time_embed_dim),
596 | nn.SiLU(),
597 | linear(time_embed_dim, time_embed_dim),
598 | )
599 |
600 | if self.num_classes is not None:
601 | self.label_emb = nn.Embedding(num_classes, time_embed_dim)
602 |
603 | ch = input_ch = int(channel_mult[0] * model_channels)
604 | self.input_blocks = nn.ModuleList(
605 | [TimestepEmbedSequential(conv_nd(dims, in_channels, ch, 3, padding=1))]
606 | )
607 | self._feature_size = ch
608 | input_block_chans = [ch]
609 | ds = 1
610 | for level, mult in enumerate(channel_mult):
611 | for _ in range(num_res_blocks):
612 | layers = [
613 | ResBlock(
614 | ch,
615 | time_embed_dim,
616 | dropout,
617 | out_channels=int(mult * model_channels),
618 | dims=dims,
619 | use_checkpoint=use_checkpoint,
620 | use_scale_shift_norm=use_scale_shift_norm,
621 | )
622 | ]
623 | ch = int(mult * model_channels)
624 | if ds in attention_resolutions:
625 | layers.append(
626 | AttentionBlock(
627 | ch,
628 | use_checkpoint=use_checkpoint,
629 | num_heads=num_heads,
630 | num_head_channels=num_head_channels,
631 | use_new_attention_order=use_new_attention_order,
632 | )
633 | )
634 | self.input_blocks.append(TimestepEmbedSequential(*layers))
635 | self._feature_size += ch
636 | input_block_chans.append(ch)
637 | if level != len(channel_mult) - 1:
638 | out_ch = ch
639 | self.input_blocks.append(
640 | TimestepEmbedSequential(
641 | ResBlock(
642 | ch,
643 | time_embed_dim,
644 | dropout,
645 | out_channels=out_ch,
646 | dims=dims,
647 | use_checkpoint=use_checkpoint,
648 | use_scale_shift_norm=use_scale_shift_norm,
649 | down=True,
650 | )
651 | if resblock_updown
652 | else Downsample(
653 | ch, conv_resample, dims=dims, out_channels=out_ch
654 | )
655 | )
656 | )
657 | ch = out_ch
658 | input_block_chans.append(ch)
659 | ds *= 2
660 | self._feature_size += ch
661 |
662 | self.middle_block = TimestepEmbedSequential(
663 | ResBlock(
664 | ch,
665 | time_embed_dim,
666 | dropout,
667 | dims=dims,
668 | use_checkpoint=use_checkpoint,
669 | use_scale_shift_norm=use_scale_shift_norm,
670 | ),
671 | AttentionBlock(
672 | ch,
673 | use_checkpoint=use_checkpoint,
674 | num_heads=num_heads,
675 | num_head_channels=num_head_channels,
676 | use_new_attention_order=use_new_attention_order,
677 | ),
678 | ResBlock(
679 | ch,
680 | time_embed_dim,
681 | dropout,
682 | dims=dims,
683 | use_checkpoint=use_checkpoint,
684 | use_scale_shift_norm=use_scale_shift_norm,
685 | ),
686 | )
687 | self._feature_size += ch
688 |
689 | self.output_blocks = nn.ModuleList([])
690 | for level, mult in list(enumerate(channel_mult))[::-1]:
691 | for i in range(num_res_blocks + 1):
692 | ich = input_block_chans.pop()
693 | layers = [
694 | ResBlock(
695 | ch + ich,
696 | time_embed_dim,
697 | dropout,
698 | out_channels=int(model_channels * mult),
699 | dims=dims,
700 | use_checkpoint=use_checkpoint,
701 | use_scale_shift_norm=use_scale_shift_norm,
702 | )
703 | ]
704 | ch = int(model_channels * mult)
705 | if ds in attention_resolutions:
706 | layers.append(
707 | AttentionBlock(
708 | ch,
709 | use_checkpoint=use_checkpoint,
710 | num_heads=num_heads_upsample,
711 | num_head_channels=num_head_channels,
712 | use_new_attention_order=use_new_attention_order,
713 | )
714 | )
715 | if level and i == num_res_blocks:
716 | out_ch = ch
717 | layers.append(
718 | ResBlock(
719 | ch,
720 | time_embed_dim,
721 | dropout,
722 | out_channels=out_ch,
723 | dims=dims,
724 | use_checkpoint=use_checkpoint,
725 | use_scale_shift_norm=use_scale_shift_norm,
726 | up=True,
727 | )
728 | if resblock_updown
729 | else Upsample(ch, conv_resample, dims=dims, out_channels=out_ch)
730 | )
731 | ds //= 2
732 | self.output_blocks.append(TimestepEmbedSequential(*layers))
733 | self._feature_size += ch
734 |
735 | self.out = nn.Sequential(
736 | normalization(ch),
737 | nn.SiLU(),
738 | zero_module(conv_nd(dims, input_ch, out_channels, 3, padding=1)),
739 | )
740 |
741 | def convert_to_fp16(self):
742 | """
743 | Convert the torso of the model to float16.
744 | """
745 | self.input_blocks.apply(convert_module_to_f16)
746 | self.middle_block.apply(convert_module_to_f16)
747 | self.output_blocks.apply(convert_module_to_f16)
748 |
749 | def convert_to_fp32(self):
750 | """
751 | Convert the torso of the model to float32.
752 | """
753 | self.input_blocks.apply(convert_module_to_f32)
754 | self.middle_block.apply(convert_module_to_f32)
755 | self.output_blocks.apply(convert_module_to_f32)
756 |
757 | def forward(self, x, timesteps, y=None):
758 | """
759 | Apply the model to an input batch.
760 |
761 | :param x: an [N x C x ...] Tensor of inputs.
762 | :param timesteps: a 1-D batch of timesteps.
763 | :param y: an [N] Tensor of labels, if class-conditional.
764 | :return: an [N x C x ...] Tensor of outputs.
765 | """
766 | assert (y is not None) == (
767 | self.num_classes is not None
768 | ), "must specify y if and only if the model is class-conditional"
769 |
770 | hs = []
771 | emb = self.time_embed(timestep_embedding(timesteps, self.model_channels))
772 |
773 | if self.num_classes is not None:
774 | assert y.shape == (x.shape[0],)
775 | emb = emb + self.label_emb(y)
776 |
777 | h = x.type(self.dtype)
778 | for module in self.input_blocks:
779 | h = module(h, emb)
780 | hs.append(h)
781 | h = self.middle_block(h, emb)
782 | for module in self.output_blocks:
783 | h = th.cat([h, hs.pop()], dim=1)
784 | h = module(h, emb)
785 | h = h.type(x.dtype)
786 | return self.out(h)
787 |
--------------------------------------------------------------------------------
/cm/network.py:
--------------------------------------------------------------------------------
1 | # Copyright (c) 2022, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
2 | #
3 | # This work is licensed under a Creative Commons
4 | # Attribution-NonCommercial-ShareAlike 4.0 International License.
5 | # You should have received a copy of the license along with this
6 | # work. If not, see http://creativecommons.org/licenses/by-nc-sa/4.0/
7 |
8 | """Model architectures and preconditioning schemes used in the paper
9 | "Elucidating the Design Space of Diffusion-Based Generative Models"."""
10 |
11 | import numpy as np
12 | import torch
13 | # from torch_utils import persistence
14 | from torch.nn.functional import silu
15 | import torch.nn as nn
16 | # from .fp16_util import convert_module_to_f16, convert_module_to_f32
17 | # from .nn_test import (
18 | # checkpoint,
19 | # conv_nd,
20 | # linear,
21 | # avg_pool_nd,
22 | # zero_module,
23 | # normalization,
24 | # timestep_embedding,
25 | # )
26 |
27 | #----------------------------------------------------------------------------
28 | # Unified routine for initializing weights and biases.
29 |
30 | def weight_init(shape, mode, fan_in, fan_out):
31 | if mode == 'xavier_uniform': return np.sqrt(6 / (fan_in + fan_out)) * (torch.rand(*shape) * 2 - 1)
32 | if mode == 'xavier_normal': return np.sqrt(2 / (fan_in + fan_out)) * torch.randn(*shape)
33 | if mode == 'kaiming_uniform': return np.sqrt(3 / fan_in) * (torch.rand(*shape) * 2 - 1)
34 | if mode == 'kaiming_normal': return np.sqrt(1 / fan_in) * torch.randn(*shape)
35 | raise ValueError(f'Invalid init mode "{mode}"')
36 |
37 |
38 | def convert_module_to_f16(l):
39 | """
40 | Convert primitive modules to float16.
41 | """
42 | if isinstance(l, (Conv2d)):
43 | if l.weight is not None:
44 | l.weight.data = l.weight.data.half()
45 | if l.bias is not None:
46 | l.bias.data = l.bias.data.half()
47 |
48 |
49 | def convert_module_to_f32(l):
50 | """
51 | Convert primitive modules to float32, undoing convert_module_to_f16().
52 | """
53 | if isinstance(l, (Conv2d)):
54 | if l.weight is not None:
55 | l.weight.data = l.weight.data.float()
56 | if l.bias is not None:
57 | l.bias.data = l.bias.data.float()
58 |
59 | #----------------------------------------------------------------------------
60 | # Fully-connected layer.
61 |
62 | # @persistence.persistent_class
63 | class Linear(torch.nn.Module):
64 | def __init__(self, in_features, out_features, bias=True, init_mode='kaiming_normal', init_weight=1, init_bias=0):
65 | super().__init__()
66 | self.in_features = in_features
67 | self.out_features = out_features
68 | init_kwargs = dict(mode=init_mode, fan_in=in_features, fan_out=out_features)
69 | self.weight = torch.nn.Parameter(weight_init([out_features, in_features], **init_kwargs) * init_weight)
70 | self.bias = torch.nn.Parameter(weight_init([out_features], **init_kwargs) * init_bias) if bias else None
71 |
72 | def forward(self, x):
73 | x = x @ self.weight.t()
74 | if self.bias is not None:
75 | x = x.add_(self.bias)
76 | return x
77 |
78 | #----------------------------------------------------------------------------
79 | # Convolutional layer with optional up/downsampling.
80 |
81 | # @persistence.persistent_class
82 | class Conv2d(torch.nn.Module):
83 | def __init__(self,
84 | in_channels, out_channels, kernel, bias=True, up=False, down=False,
85 | resample_filter=[1,1], fused_resample=False, init_mode='kaiming_normal', init_weight=1, init_bias=0,
86 | ):
87 | assert not (up and down)
88 | super().__init__()
89 | self.in_channels = in_channels
90 | self.out_channels = out_channels
91 | self.up = up
92 | self.down = down
93 | self.fused_resample = fused_resample
94 | init_kwargs = dict(mode=init_mode, fan_in=in_channels*kernel*kernel, fan_out=out_channels*kernel*kernel)
95 | self.weight = torch.nn.Parameter(weight_init([out_channels, in_channels, kernel, kernel], **init_kwargs) * init_weight) if kernel else None
96 | self.bias = torch.nn.Parameter(weight_init([out_channels], **init_kwargs) * init_bias) if kernel and bias else None
97 | f = torch.as_tensor(resample_filter, dtype=torch.float32)
98 | f = f.ger(f).unsqueeze(0).unsqueeze(1) / f.sum().square()
99 | self.register_buffer('resample_filter', f if up or down else None)
100 |
101 | def forward(self, x):
102 | w = self.weight.to(x.dtype) if self.weight is not None else None
103 | b = self.bias.to(x.dtype) if self.bias is not None else None
104 | f = self.resample_filter.to(x.dtype) if self.resample_filter is not None else None
105 | w_pad = w.shape[-1] // 2 if w is not None else 0
106 | f_pad = (f.shape[-1] - 1) // 2 if f is not None else 0
107 |
108 | if self.fused_resample and self.up and w is not None:
109 | x = torch.nn.functional.conv_transpose2d(x, f.mul(4).tile([self.in_channels, 1, 1, 1]), groups=self.in_channels, stride=2, padding=max(f_pad - w_pad, 0))
110 | x = torch.nn.functional.conv2d(x, w, padding=max(w_pad - f_pad, 0))
111 | elif self.fused_resample and self.down and w is not None:
112 | x = torch.nn.functional.conv2d(x, w, padding=w_pad+f_pad)
113 | x = torch.nn.functional.conv2d(x, f.tile([self.out_channels, 1, 1, 1]), groups=self.out_channels, stride=2)
114 | else:
115 | if self.up:
116 | x = torch.nn.functional.conv_transpose2d(x, f.mul(4).tile([self.in_channels, 1, 1, 1]), groups=self.in_channels, stride=2, padding=f_pad)
117 | if self.down:
118 | x = torch.nn.functional.conv2d(x, f.tile([self.in_channels, 1, 1, 1]), groups=self.in_channels, stride=2, padding=f_pad)
119 | if w is not None:
120 | x = torch.nn.functional.conv2d(x, w, padding=w_pad)
121 | if b is not None:
122 | x = x.add_(b.reshape(1, -1, 1, 1))
123 | return x
124 |
125 | #----------------------------------------------------------------------------
126 | # Group normalization.
127 |
128 | # @persistence.persistent_class
129 | class GroupNorm(torch.nn.Module):
130 | def __init__(self, num_channels, num_groups=32, min_channels_per_group=4, eps=1e-5):
131 | super().__init__()
132 | self.num_groups = min(num_groups, num_channels // min_channels_per_group)
133 | self.eps = eps
134 | self.weight = torch.nn.Parameter(torch.ones(num_channels))
135 | self.bias = torch.nn.Parameter(torch.zeros(num_channels))
136 |
137 | def forward(self, x):
138 | x = torch.nn.functional.group_norm(x, num_groups=self.num_groups, weight=self.weight.to(x.dtype), bias=self.bias.to(x.dtype), eps=self.eps)
139 | return x
140 |
141 | #----------------------------------------------------------------------------
142 | # Attention weight computation, i.e., softmax(Q^T * K).
143 | # Performs all computation using FP32, but uses the original datatype for
144 | # inputs/outputs/gradients to conserve memory.
145 |
146 | class AttentionOp(torch.autograd.Function):
147 | @staticmethod
148 | def forward(ctx, q, k):
149 | # w = torch.einsum('ncq,nck->nqk', q.to(torch.float32), (k / np.sqrt(k.shape[1])).to(torch.float32)).softmax(dim=2).to(q.dtype)
150 |
151 | w = torch.einsum('ncq,nck->nqk', q.to(torch.float32), (k / np.sqrt(k.shape[1])).to(torch.float32))
152 | # w = w.softmax(dim=2)
153 | w = our_softmax(w, dim=2)
154 | w = w.to(q.dtype)
155 | ctx.save_for_backward(q, k, w)
156 | return w
157 |
158 | @staticmethod
159 | def backward(ctx, dw):
160 | q, k, w = ctx.saved_tensors
161 | db = torch._softmax_backward_data(grad_output=dw.to(torch.float32), output=w.to(torch.float32), dim=2, input_dtype=torch.float32)
162 | dq = torch.einsum('nck,nqk->ncq', k.to(torch.float32), db).to(q.dtype) / np.sqrt(k.shape[1])
163 | dk = torch.einsum('ncq,nqk->nck', q.to(torch.float32), db).to(k.dtype) / np.sqrt(k.shape[1])
164 | return dq, dk
165 |
166 | @torch.jit.script
167 | def our_softmax(x, dim:int=-1):
168 | """
169 | x: (B, C, C)
170 | """
171 |
172 | maxes = torch.max(x, dim, keepdim=True)[0]
173 | x_exp = torch.exp(x-maxes)
174 | x_exp_sum = torch.sum(x_exp, dim, keepdim=True)
175 | output_custom = x_exp/x_exp_sum
176 | return output_custom
177 |
178 | #----------------------------------------------------------------------------
179 | # Unified U-Net block with optional up/downsampling and self-attention.
180 | # Represents the union of all features employed by the DDPM++, NCSN++, and
181 | # ADM architectures.
182 |
183 | # @persistence.persistent_class
184 | class UNetBlock(torch.nn.Module):
185 | def __init__(self,
186 | in_channels, out_channels, emb_channels, up=False, down=False, attention=False,
187 | num_heads=None, channels_per_head=64, dropout=0, skip_scale=1, eps=1e-5,
188 | resample_filter=[1,1], resample_proj=False, adaptive_scale=True,
189 | init=dict(), init_zero=dict(init_weight=0), init_attn=None,
190 | # flash_atten=True,
191 | flash_atten=False,
192 | ):
193 | super().__init__()
194 | self.in_channels = in_channels
195 | self.out_channels = out_channels
196 | self.emb_channels = emb_channels
197 | self.num_heads = 0 if not attention else num_heads if num_heads is not None else out_channels // channels_per_head
198 | self.dropout = dropout
199 | self.skip_scale = skip_scale
200 | self.adaptive_scale = adaptive_scale
201 | self.flash_atten = flash_atten
202 | if self.flash_atten and self.num_heads:
203 | from einops import rearrange
204 | import sys
205 | sys.path.insert(0, "/home/work/workspace/flash-attention")
206 | from flash_attn import flash_attn_varlen_qkvpacked_func, flash_attn_qkvpacked_func
207 |
208 | self.rearrange = rearrange
209 | # self.inner_attn = flash_attn_varlen_qkvpacked_func
210 | self.inner_attn = flash_attn_qkvpacked_func
211 |
212 | self.norm0 = GroupNorm(num_channels=in_channels, eps=eps)
213 | self.conv0 = Conv2d(in_channels=in_channels, out_channels=out_channels, kernel=3, up=up, down=down, resample_filter=resample_filter, **init)
214 | self.affine = Linear(in_features=emb_channels, out_features=out_channels*(2 if adaptive_scale else 1), **init)
215 | self.norm1 = GroupNorm(num_channels=out_channels, eps=eps)
216 | self.conv1 = Conv2d(in_channels=out_channels, out_channels=out_channels, kernel=3, **init_zero)
217 |
218 | self.skip = None
219 | if out_channels != in_channels or up or down:
220 | kernel = 1 if resample_proj or out_channels!= in_channels else 0
221 | self.skip = Conv2d(in_channels=in_channels, out_channels=out_channels, kernel=kernel, up=up, down=down, resample_filter=resample_filter, **init)
222 |
223 | if self.num_heads:
224 | self.norm2 = GroupNorm(num_channels=out_channels, eps=eps)
225 | self.qkv = Conv2d(in_channels=out_channels, out_channels=out_channels*3, kernel=1, **(init_attn if init_attn is not None else init))
226 | self.proj = Conv2d(in_channels=out_channels, out_channels=out_channels, kernel=1, **init_zero)
227 |
228 | def forward(self, x, emb):
229 | orig = x
230 | x = self.conv0(silu(self.norm0(x)))
231 |
232 | params = self.affine(emb).unsqueeze(2).unsqueeze(3).to(x.dtype)
233 | if self.adaptive_scale:
234 | scale, shift = params.chunk(chunks=2, dim=1)
235 | x = silu(torch.addcmul(shift, self.norm1(x), scale + 1))
236 | else:
237 | x = silu(self.norm1(x.add_(params)))
238 |
239 | x = self.conv1(torch.nn.functional.dropout(x, p=self.dropout, training=self.training))
240 | x = x.add_(self.skip(orig) if self.skip is not None else orig)
241 | x = x * self.skip_scale
242 |
243 | if self.num_heads:
244 | if self.flash_atten:
245 | b, _, *spatial = x.shape
246 | qkv = self.qkv(self.norm2(x)).view(b, -1, np.prod(spatial))
247 | qkv = self.rearrange(
248 | qkv, "b (h d three) s -> b s three h d", three=3, h=self.num_heads
249 | )
250 | a = self.inner_attn(qkv)
251 | a = self.rearrange(a, "b s h d -> b (h d) s")
252 | a = a.view(b, -1, *spatial)
253 |
254 | else:
255 | q, k, v = self.qkv(self.norm2(x)).reshape(x.shape[0] * self.num_heads, x.shape[1] // self.num_heads, 3, -1).unbind(2)
256 | # w = AttentionOp.apply(q, k)
257 |
258 | w = torch.einsum('ncq,nck->nqk', q.to(torch.float32), (k / np.sqrt(k.shape[1])).to(torch.float32))
259 | w = our_softmax(w, dim=2)
260 | w = w.to(q.dtype)
261 |
262 | a = torch.einsum('nqk,nck->ncq', w, v)
263 | a = a.reshape(*x.shape).contiguous()
264 | # q, k, v = self.qkv(self.norm2(x)).reshape(x.shape[0] * self.num_heads, x.shape[1] // self.num_heads, 3, -1).unbind(2)
265 | # w = AttentionOp.apply(q, k)
266 | # a = torch.einsum('nqk,nck->ncq', w, v)
267 | # x = self.proj(a.reshape(*x.shape)).add_(x)
268 | x = self.proj(a).add_(x)
269 | x = x * self.skip_scale
270 |
271 | # if x.isnan().sum()>0:
272 | # import ipdb; ipdb.set_trace()
273 | return x
274 |
275 | #----------------------------------------------------------------------------
276 | # Timestep embedding used in the DDPM++ and ADM architectures.
277 |
278 | # @persistence.persistent_class
279 | class PositionalEmbedding(torch.nn.Module):
280 | def __init__(self, num_channels, max_positions=10000, endpoint=False):
281 | super().__init__()
282 | self.num_channels = num_channels
283 | self.max_positions = max_positions
284 | self.endpoint = endpoint
285 |
286 | def forward(self, x):
287 | freqs = torch.arange(start=0, end=self.num_channels//2, dtype=torch.float32, device=x.device)
288 | freqs = freqs / (self.num_channels // 2 - (1 if self.endpoint else 0))
289 | freqs = (1 / self.max_positions) ** freqs
290 | x = x.ger(freqs)
291 | x = torch.cat([x.cos(), x.sin()], dim=1)
292 | return x
293 |
294 | #----------------------------------------------------------------------------
295 | # Timestep embedding used in the NCSN++ architecture.
296 |
297 | # @persistence.persistent_class
298 | class FourierEmbedding(torch.nn.Module):
299 | def __init__(self, num_channels, scale=16):
300 | super().__init__()
301 | self.register_buffer('freqs', torch.randn(num_channels // 2) * scale)
302 |
303 | def forward(self, x):
304 | x = x.ger((2 * np.pi * self.freqs))
305 | x = torch.cat([x.cos(), x.sin()], dim=1)
306 | return x
307 |
308 | #----------------------------------------------------------------------------
309 | # Reimplementation of the DDPM++ and NCSN++ architectures from the paper
310 | # "Score-Based Generative Modeling through Stochastic Differential
311 | # Equations". Equivalent to the original implementation by Song et al.,
312 | # available at https://github.com/yang-song/score_sde_pytorch
313 |
314 | #----------------------------------------------------------------------------
315 | # Reimplementation of the ADM architecture from the paper
316 | # "Diffusion Models Beat GANS on Image Synthesis". Equivalent to the
317 | # original implementation by Dhariwal and Nichol, available at
318 | # https://github.com/openai/guided-diffusion
319 |
320 | # @persistence.persistent_class
321 | class DhariwalUNet(torch.nn.Module):
322 | def __init__(self,
323 | image_size,
324 | in_channels,
325 | model_channels,
326 | out_channels,
327 | num_res_blocks,
328 | attention_resolutions,
329 | dropout=0,
330 | channel_mult=(1, 2, 4, 8),
331 | conv_resample=True,
332 | dims=2,
333 | num_classes=None,
334 | use_checkpoint=False,
335 | use_fp16=False,
336 | num_heads=1,
337 | num_head_channels=-1,
338 | num_heads_upsample=-1,
339 | use_scale_shift_norm=False,
340 | resblock_updown=False,
341 | use_new_attention_order=False,
342 | ):
343 |
344 | # img_resolution, # Image resolution at input/output.
345 | # in_channels, # Number of color channels at input.
346 | # out_channels, # Number of color channels at output.
347 | # label_dim = 0, # Number of class labels, 0 = unconditional.
348 | # augment_dim = 0, # Augmentation label dimensionality, 0 = no augmentation.
349 |
350 | # model_channels = 192, # Base multiplier for the number of channels.
351 | # channel_mult = [1,2,3,4], # Per-resolution multipliers for the number of channels.
352 | # channel_mult_emb = 4, # Multiplier for the dimensionality of the embedding vector.
353 | # num_blocks = 3, # Number of residual blocks per resolution.
354 | # attn_resolutions = [32,16,8], # List of resolutions with self-attention.
355 | # dropout = 0.10, # List of resolutions with self-attention.
356 | # label_dropout = 0, # Dropout probability of class labels for classifier-free guidance.
357 |
358 | super().__init__()
359 | self.label_dropout = 0
360 | self.model_channels = model_channels
361 | self.channel_mult_emb = 4
362 | self.augment_dim =0
363 | self.in_channels = in_channels
364 | self.image_size = image_size
365 | self.num_classes = num_classes
366 | self.dtype = torch.float16 if use_fp16 else torch.float32
367 |
368 | attn_resolutions = [32,16,8]
369 | img_resolution = image_size
370 | num_blocks = num_res_blocks
371 |
372 |
373 | emb_channels = model_channels * self.channel_mult_emb
374 | init = dict(init_mode='kaiming_uniform', init_weight=np.sqrt(1/3), init_bias=np.sqrt(1/3))
375 | init_zero = dict(init_mode='kaiming_uniform', init_weight=0, init_bias=0)
376 | block_kwargs = dict(emb_channels=emb_channels, channels_per_head=64, dropout=dropout, init=init, init_zero=init_zero)
377 |
378 | # Mapping.
379 | self.map_noise = PositionalEmbedding(num_channels=model_channels)
380 | # time_embed_dim = model_channels * 4
381 | # self.time_embed = nn.Sequential(
382 | # linear(model_channels, time_embed_dim),
383 | # nn.SiLU(),
384 | # linear(time_embed_dim, time_embed_dim),
385 | # )
386 |
387 |
388 | self.map_augment = Linear(in_features=self.augment_dim, out_features=model_channels, bias=False, **init_zero) if self.augment_dim else None
389 |
390 | self.map_layer0 = Linear(in_features=model_channels, out_features=emb_channels, **init)
391 |
392 |
393 | self.map_layer1 = Linear(in_features=emb_channels, out_features=emb_channels, **init)
394 |
395 |
396 | self.map_label = Linear(in_features=num_classes, out_features=emb_channels, bias=False, init_mode='kaiming_normal', init_weight=np.sqrt(num_classes)) if num_classes else None
397 |
398 | # Encoder.
399 | self.enc = torch.nn.ModuleDict()
400 | cout = in_channels
401 | for level, mult in enumerate(channel_mult):
402 | res = img_resolution >> level
403 | if level == 0:
404 | cin = cout
405 | cout = model_channels * mult
406 | self.enc[f'{res}x{res}_conv'] = Conv2d(in_channels=cin, out_channels=cout, kernel=3, **init)
407 | else:
408 | self.enc[f'{res}x{res}_down'] = UNetBlock(in_channels=cout, out_channels=cout, down=True, **block_kwargs)
409 | for idx in range(num_blocks):
410 | cin = cout
411 | cout = model_channels * mult
412 | self.enc[f'{res}x{res}_block{idx}'] = UNetBlock(in_channels=cin, out_channels=cout, attention=(res in attn_resolutions), **block_kwargs)
413 | skips = [block.out_channels for block in self.enc.values()]
414 |
415 | # Decoder.
416 | self.dec = torch.nn.ModuleDict()
417 | for level, mult in reversed(list(enumerate(channel_mult))):
418 | res = img_resolution >> level
419 | if level == len(channel_mult) - 1:
420 | self.dec[f'{res}x{res}_in0'] = UNetBlock(in_channels=cout, out_channels=cout, attention=True, **block_kwargs)
421 | self.dec[f'{res}x{res}_in1'] = UNetBlock(in_channels=cout, out_channels=cout, **block_kwargs)
422 | else:
423 | self.dec[f'{res}x{res}_up'] = UNetBlock(in_channels=cout, out_channels=cout, up=True, **block_kwargs)
424 | for idx in range(num_blocks + 1):
425 | cin = cout + skips.pop()
426 | cout = model_channels * mult
427 | self.dec[f'{res}x{res}_block{idx}'] = UNetBlock(in_channels=cin, out_channels=cout, attention=(res in attn_resolutions), **block_kwargs)
428 | self.out_norm = GroupNorm(num_channels=cout)
429 | self.out_conv = Conv2d(in_channels=cout, out_channels=out_channels, kernel=3, **init_zero)
430 |
431 | def convert_to_fp16(self):
432 | """
433 | Convert the torso of the model to float16.
434 | """
435 | self.enc.apply(convert_module_to_f16)
436 | # self.middle_block.apply(convert_module_to_f16)
437 | self.dec.apply(convert_module_to_f16)
438 |
439 | def convert_to_fp32(self):
440 | """
441 | Convert the torso of the model to float32.
442 | """
443 | self.enc.apply(convert_module_to_f32)
444 | # self.middle_block.apply(convert_module_to_f32)
445 | self.dec.apply(convert_module_to_f32)
446 |
447 | def forward(self, x, timesteps, y):
448 | # Mapping.
449 | class_labels = torch.nn.functional.one_hot(y, num_classes=self.num_classes).to(x.dtype)
450 | noise_labels = timesteps
451 |
452 | emb = self.map_noise(noise_labels)
453 | # emb = self.time_embed(timestep_embedding(timesteps, self.model_channels))
454 |
455 | # if self.map_augment is not None and augment_labels is not None:
456 | # emb = emb + self.map_augment(augment_labels)
457 | emb = silu(self.map_layer0(emb))
458 | emb = self.map_layer1(emb)
459 |
460 |
461 | if self.map_label is not None:
462 | tmp = class_labels
463 | if self.training and self.label_dropout:
464 | tmp = tmp * (torch.rand([x.shape[0], 1], device=x.device) >= self.label_dropout)
465 | emb = emb + self.map_label(tmp)
466 | emb = silu(emb)
467 |
468 | # Encoder.
469 | skips = []
470 | x = x.type(self.dtype)
471 | for block in self.enc.values():
472 | x = block(x, emb) if isinstance(block, UNetBlock) else block(x)
473 | skips.append(x)
474 |
475 | # Decoder.
476 | for block in self.dec.values():
477 | if x.shape[1] != block.in_channels:
478 | x = torch.cat([x, skips.pop()], dim=1)
479 | x = block(x, emb)
480 | x = x.type(self.dtype)
481 | out = self.out_conv(silu(self.out_norm(x)))
482 | return out
483 |
484 |
485 | class SongUNet(torch.nn.Module):
486 | def __init__(self,
487 | image_size,
488 | in_channels,
489 | model_channels,
490 | out_channels,
491 | num_res_blocks,
492 | attention_resolutions=(16),
493 | dropout=0,
494 | channel_mult=(1, 2, 4, 8),
495 | conv_resample=True,
496 | dims=2,
497 | num_classes=None,
498 | use_checkpoint=False,
499 | use_fp16=False,
500 | num_heads=1,
501 | num_head_channels=-1,
502 | num_heads_upsample=-1,
503 | use_scale_shift_norm=False,
504 | resblock_updown=False,
505 | use_new_attention_order=False,
506 | random_init=False,
507 | ):
508 | super().__init__()
509 | self.in_channels = in_channels
510 | self.image_size = image_size
511 | self.num_classes = num_classes
512 | self.random_init = random_init
513 | self.dtype = torch.float16 if use_fp16 else torch.float32
514 |
515 | img_resolution=image_size # Image resolution at input/output.
516 | in_channels=in_channels # Number of color channels at input.
517 | out_channels=out_channels # Number of color channels at output.
518 | label_dim = num_classes if num_classes else 0 # Number of class labels, 0 = unconditional.
519 | augment_dim = 0 # Augmentation label dimensionality, 0 = no augmentation.
520 |
521 | model_channels = model_channels # Base multiplier for the number of channels.
522 | channel_mult = channel_mult # Per-resolution multipliers for the number of channels.
523 | channel_mult_emb = 4 # Multiplier for the dimensionality of the embedding vector.
524 | num_blocks = num_res_blocks # Number of residual blocks per resolution.
525 | attn_resolutions = attention_resolutions # List of resolutions with self-attention.
526 | dropout = 0.0 # Dropout probability of intermediate activations.
527 | label_dropout = 0 # Dropout probability of class labels for classifier-free guidance.
528 |
529 | embedding_type = 'positional' # Timestep embedding type: 'positional' for DDPM++, 'fourier' for NCSN++.
530 | channel_mult_noise = 1 # Timestep embedding size: 1 for DDPM++, 2 for NCSN++.
531 | encoder_type = 'standard' # Encoder architecture: 'standard' for DDPM++, 'residual' for NCSN++.
532 | decoder_type = 'standard' # Decoder architecture: 'standard' for both DDPM++ and NCSN++.
533 | resample_filter = [1,1] # Resampling filter: [1,1] for DDPM++, [1,3,3,1] for NCSN++
534 |
535 | self.label_dropout = label_dropout
536 | emb_channels = model_channels * channel_mult_emb
537 | noise_channels = model_channels * channel_mult_noise
538 | init = dict(init_mode='xavier_uniform')
539 | init_zero = dict(init_mode='xavier_uniform', init_weight=1e-5)
540 | init_attn = dict(init_mode='xavier_uniform', init_weight=np.sqrt(0.2))
541 | block_kwargs = dict(
542 | emb_channels=emb_channels, num_heads=1, dropout=dropout, skip_scale=np.sqrt(0.5), eps=1e-6,
543 | resample_filter=resample_filter, resample_proj=True, adaptive_scale=False,
544 | init=init, init_zero=init_zero, init_attn=init_attn,
545 | )
546 |
547 | # Mapping.
548 | self.map_noise = PositionalEmbedding(num_channels=noise_channels, endpoint=True) if embedding_type == 'positional' else FourierEmbedding(num_channels=noise_channels)
549 | self.map_label = Linear(in_features=label_dim, out_features=noise_channels, **init) if label_dim else None
550 | self.map_augment = Linear(in_features=augment_dim, out_features=noise_channels, bias=False, **init) if augment_dim else None
551 | self.map_layer0 = Linear(in_features=noise_channels, out_features=emb_channels, **init)
552 | self.map_layer1 = Linear(in_features=emb_channels, out_features=emb_channels, **init)
553 |
554 | if self.random_init:
555 | self.map_init_cond_layer0 = Linear(in_features=noise_channels, out_features=emb_channels, **init)
556 | self.map_init_cond_layer1 = Linear(in_features=emb_channels, out_features=emb_channels, **init)
557 |
558 | # Encoder.
559 | self.enc = torch.nn.ModuleDict()
560 | cout = in_channels
561 | caux = in_channels
562 | for level, mult in enumerate(channel_mult):
563 | res = img_resolution >> level
564 | if level == 0:
565 | cin = cout
566 | cout = model_channels
567 | self.enc[f'{res}x{res}_conv'] = Conv2d(in_channels=cin, out_channels=cout, kernel=3, **init)
568 | else:
569 | self.enc[f'{res}x{res}_down'] = UNetBlock(in_channels=cout, out_channels=cout, down=True, **block_kwargs)
570 | if encoder_type == 'skip':
571 | self.enc[f'{res}x{res}_aux_down'] = Conv2d(in_channels=caux, out_channels=caux, kernel=0, down=True, resample_filter=resample_filter)
572 | self.enc[f'{res}x{res}_aux_skip'] = Conv2d(in_channels=caux, out_channels=cout, kernel=1, **init)
573 | if encoder_type == 'residual':
574 | self.enc[f'{res}x{res}_aux_residual'] = Conv2d(in_channels=caux, out_channels=cout, kernel=3, down=True, resample_filter=resample_filter, fused_resample=True, **init)
575 | caux = cout
576 | for idx in range(num_blocks):
577 | cin = cout
578 | cout = model_channels * mult
579 | attn = (res in attn_resolutions)
580 | self.enc[f'{res}x{res}_block{idx}'] = UNetBlock(in_channels=cin, out_channels=cout, attention=attn, **block_kwargs)
581 | skips = [block.out_channels for name, block in self.enc.items() if 'aux' not in name]
582 |
583 | # Decoder.
584 | self.dec = torch.nn.ModuleDict()
585 | for level, mult in reversed(list(enumerate(channel_mult))):
586 | res = img_resolution >> level
587 | if level == len(channel_mult) - 1:
588 | self.dec[f'{res}x{res}_in0'] = UNetBlock(in_channels=cout, out_channels=cout, attention=True, **block_kwargs)
589 | self.dec[f'{res}x{res}_in1'] = UNetBlock(in_channels=cout, out_channels=cout, **block_kwargs)
590 | else:
591 | self.dec[f'{res}x{res}_up'] = UNetBlock(in_channels=cout, out_channels=cout, up=True, **block_kwargs)
592 | for idx in range(num_blocks + 1):
593 | cin = cout + skips.pop()
594 | cout = model_channels * mult
595 | attn = (idx == num_blocks and res in attn_resolutions)
596 | self.dec[f'{res}x{res}_block{idx}'] = UNetBlock(in_channels=cin, out_channels=cout, attention=attn, **block_kwargs)
597 | if decoder_type == 'skip' or level == 0:
598 | if decoder_type == 'skip' and level < len(channel_mult) - 1:
599 | self.dec[f'{res}x{res}_aux_up'] = Conv2d(in_channels=out_channels, out_channels=out_channels, kernel=0, up=True, resample_filter=resample_filter)
600 | self.dec[f'{res}x{res}_aux_norm'] = GroupNorm(num_channels=cout, eps=1e-6)
601 | self.dec[f'{res}x{res}_aux_conv'] = Conv2d(in_channels=cout, out_channels=out_channels, kernel=3, **init_zero)
602 |
603 | def convert_to_fp16(self):
604 | """
605 | Convert the torso of the model to float16.
606 | """
607 | self.enc.apply(convert_module_to_f16)
608 | # self.middle_block.apply(convert_module_to_f16)
609 | self.dec.apply(convert_module_to_f16)
610 |
611 | def convert_to_fp32(self):
612 | """
613 | Convert the torso of the model to float32.
614 | """
615 | self.enc.apply(convert_module_to_f32)
616 | # self.middle_block.apply(convert_module_to_f32)
617 | self.dec.apply(convert_module_to_f32)
618 |
619 | def forward(self, x, timesteps, y=None):
620 | # Mapping.
621 | class_labels = torch.nn.functional.one_hot(y, num_classes=self.num_classes).to(x.dtype) if y is not None else None
622 | if not isinstance(timesteps, list):
623 | timesteps = [timesteps]
624 |
625 | noise_labels = timesteps[0]
626 |
627 | # Mapping.
628 | emb = self.map_noise(noise_labels)
629 | emb = emb.reshape(emb.shape[0], 2, -1).flip(1).reshape(*emb.shape) # swap sin/cos
630 | if self.map_label is not None:
631 | tmp = class_labels
632 | if self.training and self.label_dropout:
633 | tmp = tmp * (torch.rand([x.shape[0], 1], device=x.device) >= self.label_dropout).to(tmp.dtype)
634 | emb = emb + self.map_label(tmp * np.sqrt(self.map_label.in_features))
635 | # if self.map_augment is not None and augment_labels is not None:
636 | # emb = emb + self.map_augment(augment_labels)
637 | emb = silu(self.map_layer0(emb))
638 | emb = silu(self.map_layer1(emb))
639 |
640 | if self.random_init:
641 | emb_init = self.map_noise(timesteps[1])
642 | emb_init = emb_init.reshape(emb_init.shape[0], 2, -1).flip(1).reshape(*emb_init.shape) # swap sin/cos
643 | emb_init = silu(self.map_init_cond_layer0(emb_init))
644 | emb_init = silu(self.map_init_cond_layer1(emb_init))
645 | emb = emb + emb_init
646 |
647 | # Encoder.
648 | skips = []
649 | x = x.type(self.dtype)
650 | aux = x
651 | for name, block in self.enc.items():
652 | if 'aux_down' in name:
653 | aux = block(aux)
654 | elif 'aux_skip' in name:
655 | x = skips[-1] = x + block(aux)
656 | elif 'aux_residual' in name:
657 | x = skips[-1] = aux = (x + block(aux)) / np.sqrt(2)
658 | else:
659 | x = block(x, emb) if isinstance(block, UNetBlock) else block(x)
660 | skips.append(x)
661 |
662 | # Decoder.
663 | aux = None
664 | tmp = None
665 | x = x.type(self.dtype)
666 | for name, block in self.dec.items():
667 | if 'aux_up' in name:
668 | aux = block(aux)
669 | elif 'aux_norm' in name:
670 | tmp = block(x)
671 | elif 'aux_conv' in name:
672 | tmp = block(silu(tmp))
673 | aux = tmp if aux is None else tmp + aux
674 | else:
675 | if x.shape[1] != block.in_channels:
676 | x = torch.cat([x, skips.pop()], dim=1)
677 | x = block(x, emb)
678 | return aux
679 |
680 | # @persistence.persistent_class
681 | class EDMPrecond(torch.nn.Module):
682 | def __init__(self,
683 | img_resolution, # Image resolution.
684 | img_channels, # Number of color channels.
685 | label_dim = 0, # Number of class labels, 0 = unconditional.
686 | use_fp16 = False, # Execute the underlying model at FP16 precision?
687 | sigma_min = 0, # Minimum supported noise level.
688 | sigma_max = float('inf'), # Maximum supported noise level.
689 | sigma_data = 0.5, # Expected standard deviation of the training data.
690 | model_type = 'DhariwalUNet', # Class name of the underlying model.
691 | **model_kwargs, # Keyword arguments for the underlying model.
692 | ):
693 | super().__init__()
694 | self.img_resolution = img_resolution
695 | self.img_channels = img_channels
696 | self.label_dim = label_dim
697 | self.use_fp16 = use_fp16
698 | self.sigma_min = sigma_min
699 | self.sigma_max = sigma_max
700 | self.sigma_data = sigma_data
701 | self.model = globals()[model_type](img_resolution=img_resolution, in_channels=img_channels, out_channels=img_channels, label_dim=label_dim, **model_kwargs)
702 |
703 | def forward(self, x, sigma, class_labels=None, force_fp32=False, **model_kwargs):
704 | # x = x.to(torch.float32)
705 | sigma = sigma.reshape(-1, 1, 1, 1)
706 | class_labels = None if self.label_dim == 0 else torch.zeros([1, self.label_dim], device=x.device) if class_labels is None else class_labels.reshape(-1, self.label_dim)
707 | dtype = torch.float16 if (self.use_fp16 and not force_fp32 and x.device.type == 'cuda') else torch.float32
708 |
709 | c_skip = self.sigma_data ** 2 / (sigma ** 2 + self.sigma_data ** 2)
710 | c_out = sigma * self.sigma_data / (sigma ** 2 + self.sigma_data ** 2).sqrt()
711 | c_in = 1 / (self.sigma_data ** 2 + sigma ** 2).sqrt()
712 | c_noise = sigma.log() / 4
713 |
714 | F_x = self.model((c_in * x), c_noise.flatten(), class_labels=class_labels, **model_kwargs)
715 | assert F_x.dtype == dtype
716 | D_x = c_skip * x + c_out * F_x
717 | return D_x
718 |
719 | def round_sigma(self, sigma):
720 | return torch.as_tensor(sigma)
721 |
722 | #----------------------------------------------------------------------------
723 |
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