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Author SHA1 Message Date
Phil Wang
846162ef3e just take care of the logic for AdamW and transformers 2022-04-29 11:43:26 -07:00
Phil Wang
39d3659ad9 now completely OpenAI CLIP compatible for training 2022-04-29 11:26:24 -07:00
10 changed files with 180 additions and 1133 deletions

143
README.md
View File

@@ -47,7 +47,7 @@ clip = CLIP(
use_all_token_embeds = True, # whether to use fine-grained contrastive learning (FILIP)
decoupled_contrastive_learning = True, # use decoupled contrastive learning (DCL) objective function, removing positive pairs from the denominator of the InfoNCE loss (CLOOB + DCL)
extra_latent_projection = True, # whether to use separate projections for text-to-image vs image-to-text comparisons (CLOOB)
use_visual_ssl = True, # whether to do self supervised learning on images
use_visual_ssl = True, # whether to do self supervised learning on iages
visual_ssl_type = 'simclr', # can be either 'simclr' or 'simsiam', depending on using DeCLIP or SLIP
use_mlm = False, # use masked language learning (MLM) on text (DeCLIP)
text_ssl_loss_weight = 0.05, # weight for text MLM loss
@@ -110,8 +110,7 @@ decoder = Decoder(
unet = unet,
clip = clip,
timesteps = 100,
image_cond_drop_prob = 0.1,
text_cond_drop_prob = 0.5
cond_drop_prob = 0.2
).cuda()
# mock images (get a lot of this)
@@ -230,8 +229,7 @@ decoder = Decoder(
unet = (unet1, unet2), # insert both unets in order of low resolution to highest resolution (you can have as many stages as you want here)
image_sizes = (256, 512), # resolutions, 256 for first unet, 512 for second. these must be unique and in ascending order (matches with the unets passed in)
timesteps = 1000,
image_cond_drop_prob = 0.1,
text_cond_drop_prob = 0.5
cond_drop_prob = 0.2
).cuda()
# mock images (get a lot of this)
@@ -350,8 +348,7 @@ decoder = Decoder(
image_sizes = (128, 256),
clip = clip,
timesteps = 100,
image_cond_drop_prob = 0.1,
text_cond_drop_prob = 0.5,
cond_drop_prob = 0.2,
condition_on_text_encodings = False # set this to True if you wish to condition on text during training and sampling
).cuda()
@@ -433,8 +430,8 @@ images = torch.randn(4, 3, 256, 256).cuda()
# precompute the text and image embeddings
# here using the diffusion prior class, but could be done with CLIP alone
clip_image_embeds = diffusion_prior.clip.embed_image(images).image_embed
clip_text_embeds = diffusion_prior.clip.embed_text(text).text_embed
clip_image_embeds = diffusion_prior.get_image_embed(images)
clip_text_embeds = diffusion_prior.get_text_cond(text).get('text_embed')
# feed text and images into diffusion prior network
@@ -502,7 +499,9 @@ loss.backward()
Although there is the possibility they are using an unreleased, more powerful CLIP, you can use one of the released ones, if you do not wish to train your own CLIP from scratch. This will also allow the community to more quickly validate the conclusions of the paper.
To use a pretrained OpenAI CLIP, simply import `OpenAIClipAdapter` and pass it into the `DiffusionPrior` or `Decoder` like so
First you'll need to install <a href="https://github.com/openai/CLIP#usage">the prerequisites</a>
Then to use a pretrained OpenAI CLIP, simply import `OpenAIClipAdapter` and pass it into the `DiffusionPrior` or `Decoder` like so
```python
import torch
@@ -561,8 +560,7 @@ decoder = Decoder(
image_sizes = (128, 256),
clip = clip,
timesteps = 100,
image_cond_drop_prob = 0.1,
text_cond_drop_prob = 0.5,
cond_drop_prob = 0.2,
condition_on_text_encodings = False # set this to True if you wish to condition on text during training and sampling
).cuda()
@@ -620,7 +618,7 @@ clip = CLIP(
# 3 unets for the decoder (a la cascading DDPM)
# first two unets are doing latent diffusion
# vqgan-vae must be trained beforehand
# vqgan-vae must be trained before hand
vae1 = VQGanVAE(
dim = 32,
@@ -673,8 +671,7 @@ decoder = Decoder(
unet = (unet1, unet2, unet3), # insert unets in order of low resolution to highest resolution (you can have as many stages as you want here)
image_sizes = (256, 512, 1024), # resolutions, 256 for first unet, 512 for second, 1024 for third
timesteps = 100,
image_cond_drop_prob = 0.1,
text_cond_drop_prob = 0.5
cond_drop_prob = 0.2
).cuda()
# mock images (get a lot of this)
@@ -708,83 +705,7 @@ images = decoder.sample(mock_image_embed) # (1, 3, 1024, 1024)
## Training wrapper (wip)
### Decoder Training
Training the `Decoder` may be confusing, as one needs to keep track of an optimizer for each of the `Unet`(s) separately. Each `Unet` will also need its own corresponding exponential moving average. The `DecoderTrainer` hopes to make this simple, as shown below
```python
import torch
from dalle2_pytorch import DALLE2, Unet, Decoder, CLIP, DecoderTrainer
clip = CLIP(
dim_text = 512,
dim_image = 512,
dim_latent = 512,
num_text_tokens = 49408,
text_enc_depth = 6,
text_seq_len = 256,
text_heads = 8,
visual_enc_depth = 6,
visual_image_size = 256,
visual_patch_size = 32,
visual_heads = 8
).cuda()
# mock data
text = torch.randint(0, 49408, (4, 256)).cuda()
images = torch.randn(4, 3, 256, 256).cuda()
# decoder (with unet)
unet1 = Unet(
dim = 128,
image_embed_dim = 512,
text_embed_dim = 512,
cond_dim = 128,
channels = 3,
dim_mults=(1, 2, 4, 8)
).cuda()
unet2 = Unet(
dim = 16,
image_embed_dim = 512,
text_embed_dim = 512,
cond_dim = 128,
channels = 3,
dim_mults = (1, 2, 4, 8, 16),
cond_on_text_encodings = True
).cuda()
decoder = Decoder(
unet = (unet1, unet2),
image_sizes = (128, 256),
clip = clip,
timesteps = 1000,
condition_on_text_encodings = True
).cuda()
decoder_trainer = DecoderTrainer(
decoder,
lr = 3e-4,
wd = 1e-2,
ema_beta = 0.99,
ema_update_after_step = 1000,
ema_update_every = 10,
)
for unet_number in (1, 2):
loss = decoder_trainer(images, text = text, unet_number = unet_number) # use the decoder_trainer forward
loss.backward()
decoder_trainer.update(unet_number) # update the specific unet as well as its exponential moving average
# after much training
# you can sample from the exponentially moving averaged unets as so
mock_image_embed = torch.randn(4, 512).cuda()
images = decoder_trainer.sample(mock_image_embed, text = text) # (4, 3, 256, 256)
```
Offer training wrappers
## CLI (wip)
@@ -817,25 +738,13 @@ Once built, images will be saved to the same directory the command is invoked
- [x] use inheritance just this once for sharing logic between decoder and prior network ddpms
- [x] bring in vit-vqgan https://arxiv.org/abs/2110.04627 for the latent diffusion
- [x] abstract interface for CLIP adapter class, so other CLIPs can be brought in
- [x] take care of mixed precision as well as gradient accumulation within decoder trainer
- [x] just take care of the training for the decoder in a wrapper class, as each unet in the cascade will need its own optimizer
- [x] bring in tools to train vqgan-vae
- [x] add convnext backbone for vqgan-vae (in addition to vit [vit-vqgan] + resnet)
- [ ] become an expert with unets, cleanup unet code, make it fully configurable, port all learnings over to https://github.com/lucidrains/x-unet (test out unet² in ddpm repo)
- [ ] become an expert with unets, cleanup unet code, make it fully configurable, port all learnings over to https://github.com/lucidrains/x-unet
- [ ] copy the cascading ddpm code to a separate repo (perhaps https://github.com/lucidrains/denoising-diffusion-pytorch) as the main contribution of dalle2 really is just the prior network
- [ ] transcribe code to Jax, which lowers the activation energy for distributed training, given access to TPUs
- [ ] pull logic for training diffusion prior into a class DiffusionPriorTrainer, for eventual script based + CLI based training
- [ ] train on a toy task, offer in colab
- [ ] think about how best to design a declarative training config that handles preencoding for prior and training of multiple networks in decoder
- [ ] extend diffusion head to use diffusion-gan (potentially using lightweight-gan) to speed up inference
- [ ] bring in cross-scale embedding from iclr paper https://github.com/lucidrains/vit-pytorch/blob/main/vit_pytorch/crossformer.py#L14
- [ ] figure out if possible to augment with external memory, as described in https://arxiv.org/abs/2204.11824
- [ ] test out grid attention in cascading ddpm locally, decide whether to keep or remove
- [ ] use an experimental tracker agnostic setup, as done <a href="https://github.com/lucidrains/tf-bind-transformer#simple-trainer-class-for-fine-tuning">here</a>
- [ ] make sure for the latter unets in the cascade, one can train on crops for learning super resolution (constrain the unet to be only convolutions in that case, or allow conv-like attention with rel pos bias)
- [ ] interface out the vqgan-vae so a pretrained one can be pulled off the shelf to validate latent diffusion + DALL-E2
- [ ] make sure FILIP works with DALL-E2 from x-clip https://arxiv.org/abs/2111.07783
- [ ] make sure DDPMs can be run with traditional resnet blocks (but leave convnext as an option for experimentation)
- [ ] bring in tools to train vqgan-vae
## Citations
@@ -867,22 +776,12 @@ Once built, images will be saved to the same directory the command is invoked
```bibtex
@inproceedings{Liu2022ACF,
title = {A ConvNet for the 2020s},
title = {A ConvNet for the 2020https://arxiv.org/abs/2112.11435s},
author = {Zhuang Liu and Hanzi Mao and Chaozheng Wu and Christoph Feichtenhofer and Trevor Darrell and Saining Xie},
year = {2022}
}
```
```bibtex
@article{shen2019efficient,
author = {Zhuoran Shen and Mingyuan Zhang and Haiyu Zhao and Shuai Yi and Hongsheng Li},
title = {Efficient Attention: Attention with Linear Complexities},
journal = {CoRR},
year = {2018},
url = {http://arxiv.org/abs/1812.01243},
}
```
```bibtex
@inproceedings{Tu2022MaxViTMV,
title = {MaxViT: Multi-Axis Vision Transformer},
@@ -901,14 +800,4 @@ Once built, images will be saved to the same directory the command is invoked
}
```
```bibtex
@article{Shleifer2021NormFormerIT,
title = {NormFormer: Improved Transformer Pretraining with Extra Normalization},
author = {Sam Shleifer and Jason Weston and Myle Ott},
journal = {ArXiv},
year = {2021},
volume = {abs/2110.09456}
}
```
*Creating noise from data is easy; creating data from noise is generative modeling.* - Yang Song's <a href="https://arxiv.org/abs/2011.13456">paper</a>

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@@ -1,6 +1,5 @@
from dalle2_pytorch.dalle2_pytorch import DALLE2, DiffusionPriorNetwork, DiffusionPrior, Unet, Decoder
from dalle2_pytorch.dalle2_pytorch import OpenAIClipAdapter
from dalle2_pytorch.train import DecoderTrainer
from dalle2_pytorch.vqgan_vae import VQGanVAE
from x_clip import CLIP

View File

@@ -1,7 +1,6 @@
import click
import torch
import torchvision.transforms as T
from functools import reduce
from pathlib import Path
from dalle2_pytorch import DALLE2, Decoder, DiffusionPrior

View File

@@ -3,7 +3,6 @@ from tqdm import tqdm
from inspect import isfunction
from functools import partial
from contextlib import contextmanager
from collections import namedtuple
import torch
import torch.nn.functional as F
@@ -29,9 +28,6 @@ from x_clip import CLIP
def exists(val):
return val is not None
def identity(t, *args, **kwargs):
return t
def default(val, d):
if exists(val):
return val
@@ -106,9 +102,6 @@ def unnormalize_img(normed_img):
# clip related adapters
EmbeddedText = namedtuple('EmbedTextReturn', ['text_embed', 'text_encodings', 'text_mask'])
EmbeddedImage = namedtuple('EmbedImageReturn', ['image_embed', 'image_encodings'])
class BaseClipAdapter(nn.Module):
def __init__(self, clip):
super().__init__()
@@ -160,7 +153,7 @@ class XClipAdapter(BaseClipAdapter):
encoder_output = self.clip.text_transformer(text)
text_cls, text_encodings = encoder_output[:, 0], encoder_output[:, 1:]
text_embed = self.clip.to_text_latent(text_cls)
return EmbeddedText(l2norm(text_embed), text_encodings, text_mask)
return l2norm(text_embed), text_encodings, text_mask
@torch.no_grad()
def embed_image(self, image):
@@ -168,20 +161,24 @@ class XClipAdapter(BaseClipAdapter):
encoder_output = self.clip.visual_transformer(image)
image_cls, image_encodings = encoder_output[:, 0], encoder_output[:, 1:]
image_embed = self.clip.to_visual_latent(image_cls)
return EmbeddedImage(l2norm(image_embed), image_encodings)
return l2norm(image_embed), image_encodings
class OpenAIClipAdapter(BaseClipAdapter):
def __init__(
self,
name = 'ViT-B/32'
):
import clip
openai_clip, preprocess = clip.load(name)
try:
import clip
except ImportError:
print('you must install openai clip in order to use this adapter - `pip install git+https://github.com/openai/CLIP.git` - more instructions at https://github.com/openai/CLIP#usage')
openai_clip, _ = clip.load(name)
super().__init__(openai_clip)
text_attention_final = self.find_layer('ln_final')
self.handle = text_attention_final.register_forward_hook(self._hook)
self.clip_normalize = preprocess.transforms[-1]
self.clip_normalize = T.Normalize((0.48145466, 0.4578275, 0.40821073), (0.26862954, 0.26130258, 0.27577711))
self.cleared = False
def find_layer(self, layer):
@@ -222,7 +219,7 @@ class OpenAIClipAdapter(BaseClipAdapter):
text_embed = self.clip.encode_text(text)
text_encodings = self.text_encodings
del self.text_encodings
return EmbeddedText(text_embed.float(), text_encodings.float(), text_mask)
return text_embed.float(), text_encodings.float(), text_mask
@torch.no_grad()
def embed_image(self, image):
@@ -230,7 +227,7 @@ class OpenAIClipAdapter(BaseClipAdapter):
image = resize_image_to(image, self.image_size)
image = self.clip_normalize(unnormalize_img(image))
image_embed = self.clip.encode_image(image)
return EmbeddedImage(image_embed.float(), None)
return image_embed.float(), None
# classifier free guidance functions
@@ -499,12 +496,7 @@ class SwiGLU(nn.Module):
x, gate = x.chunk(2, dim = -1)
return x * F.silu(gate)
def FeedForward(
dim,
mult = 4,
dropout = 0.,
post_activation_norm = False
):
def FeedForward(dim, mult = 4, dropout = 0., post_activation_norm = False):
""" post-activation norm https://arxiv.org/abs/2110.09456 """
inner_dim = int(mult * dim)
@@ -527,8 +519,7 @@ class Attention(nn.Module):
dim_head = 64,
heads = 8,
dropout = 0.,
causal = False,
post_norm = False
causal = False
):
super().__init__()
self.scale = dim_head ** -0.5
@@ -543,11 +534,7 @@ class Attention(nn.Module):
self.null_kv = nn.Parameter(torch.randn(2, dim_head))
self.to_q = nn.Linear(dim, inner_dim, bias = False)
self.to_kv = nn.Linear(dim, dim_head * 2, bias = False)
self.to_out = nn.Sequential(
nn.Linear(inner_dim, dim, bias = False),
LayerNorm(dim) if post_norm else nn.Identity()
)
self.to_out = nn.Linear(inner_dim, dim, bias = False)
def forward(self, x, mask = None, attn_bias = None):
b, n, device = *x.shape[:2], x.device
@@ -609,11 +596,10 @@ class CausalTransformer(nn.Module):
dim_head = 64,
heads = 8,
ff_mult = 4,
norm_out = True,
norm_out = False,
attn_dropout = 0.,
ff_dropout = 0.,
final_proj = True,
normformer = False
final_proj = True
):
super().__init__()
self.rel_pos_bias = RelPosBias(heads = heads)
@@ -621,8 +607,8 @@ class CausalTransformer(nn.Module):
self.layers = nn.ModuleList([])
for _ in range(depth):
self.layers.append(nn.ModuleList([
Attention(dim = dim, causal = True, dim_head = dim_head, heads = heads, dropout = attn_dropout, post_norm = normformer),
FeedForward(dim = dim, mult = ff_mult, dropout = ff_dropout, post_activation_norm = normformer)
Attention(dim = dim, causal = True, dim_head = dim_head, heads = heads, dropout = attn_dropout),
FeedForward(dim = dim, mult = ff_mult, dropout = ff_dropout)
]))
self.norm = LayerNorm(dim) if norm_out else nn.Identity() # unclear in paper whether they projected after the classic layer norm for the final denoised image embedding, or just had the transformer output it directly: plan on offering both options
@@ -649,14 +635,12 @@ class DiffusionPriorNetwork(nn.Module):
self,
dim,
num_timesteps = None,
l2norm_output = False, # whether to restrict image embedding output with l2norm at the end (may make it easier to learn?)
**kwargs
):
super().__init__()
self.time_embeddings = nn.Embedding(num_timesteps, dim) if exists(num_timesteps) else nn.Sequential(Rearrange('b -> b 1'), MLP(1, dim)) # also offer a continuous version of timestep embeddings, with a 2 layer MLP
self.learned_query = nn.Parameter(torch.randn(dim))
self.causal_transformer = CausalTransformer(dim = dim, **kwargs)
self.l2norm_output = l2norm_output
def forward_with_cond_scale(
self,
@@ -700,14 +684,14 @@ class DiffusionPriorNetwork(nn.Module):
# classifier free guidance
keep_mask = prob_mask_like((batch,), 1 - cond_drop_prob, device = device)
keep_mask = rearrange(keep_mask, 'b -> b 1')
cond_prob_mask = prob_mask_like((batch,), cond_drop_prob, device = device)
cond_prob_mask = rearrange(cond_prob_mask, 'b -> b 1')
mask &= keep_mask
mask &= cond_prob_mask
# whether text embedding is masked or not depends on the classifier free guidance conditional masking
mask = torch.cat((mask, keep_mask), dim = 1)
mask = torch.cat((mask, cond_prob_mask), dim = 1)
# whether text embedding is used for conditioning depends on whether text encodings are available for attention (for classifier free guidance, even though it seems from the paper it was not used in the prior ddpm, as the objective is different)
# but let's just do it right
@@ -735,8 +719,7 @@ class DiffusionPriorNetwork(nn.Module):
pred_image_embed = tokens[..., -1, :]
output_fn = l2norm if self.l2norm_output else identity
return output_fn(pred_image_embed)
return pred_image_embed
class DiffusionPrior(BaseGaussianDiffusion):
def __init__(
@@ -753,7 +736,6 @@ class DiffusionPrior(BaseGaussianDiffusion):
predict_x_start = True,
beta_schedule = "cosine",
condition_on_text_encodings = True, # the paper suggests this is needed, but you can turn it off for your CLIP preprocessed text embed -> image embed training
sampling_clamp_l2norm = False
):
super().__init__(
beta_schedule = beta_schedule,
@@ -782,9 +764,6 @@ class DiffusionPrior(BaseGaussianDiffusion):
self.predict_x_start = predict_x_start
# in paper, they do not predict the noise, but predict x0 directly for image embedding, claiming empirically better results. I'll just offer both.
# whether to force an l2norm, similar to clipping denoised, when sampling
self.sampling_clamp_l2norm = sampling_clamp_l2norm
def p_mean_variance(self, x, t, text_cond, clip_denoised: bool):
pred = self.net(x, t, **text_cond)
@@ -798,9 +777,6 @@ class DiffusionPrior(BaseGaussianDiffusion):
if clip_denoised and not self.predict_x_start:
x_recon.clamp_(-1., 1.)
if self.predict_x_start and self.sampling_clamp_l2norm:
x_recon = l2norm(x_recon)
model_mean, posterior_variance, posterior_log_variance = self.q_posterior(x_start=x_recon, x_t=x, t=t)
return model_mean, posterior_variance, posterior_log_variance
@@ -939,7 +915,6 @@ class ConvNextBlock(nn.Module):
dim_out,
*,
cond_dim = None,
time_cond_dim = None,
mult = 2,
norm = True
):
@@ -958,14 +933,6 @@ class ConvNextBlock(nn.Module):
)
)
self.time_mlp = None
if exists(time_cond_dim):
self.time_mlp = nn.Sequential(
nn.GELU(),
nn.Linear(time_cond_dim, dim)
)
self.ds_conv = nn.Conv2d(dim, dim, 7, padding = 3, groups = dim)
inner_dim = int(dim_out * mult)
@@ -978,13 +945,9 @@ class ConvNextBlock(nn.Module):
self.res_conv = nn.Conv2d(dim, dim_out, 1) if need_projection else nn.Identity()
def forward(self, x, cond = None, time = None):
def forward(self, x, cond = None):
h = self.ds_conv(x)
if exists(time) and exists(self.time_mlp):
t = self.time_mlp(time)
h = rearrange(t, 'b c -> b c 1 1') + h
if exists(self.cross_attn):
assert exists(cond)
h = self.cross_attn(h, context = cond) + h
@@ -1067,42 +1030,6 @@ class GridAttention(nn.Module):
out = rearrange(out, '(b h w) (w1 w2) c -> b c (w1 h) (w2 w)', w1 = wsz, w2 = wsz, h = h // wsz, w = w // wsz)
return out
class LinearAttention(nn.Module):
def __init__(
self,
dim,
dim_head = 32,
heads = 8
):
super().__init__()
self.scale = dim_head ** -0.5
self.heads = heads
inner_dim = dim_head * heads
self.norm = ChanLayerNorm(dim)
self.nonlin = nn.GELU()
self.to_qkv = nn.Conv2d(dim, inner_dim * 3, 1, bias = False)
self.to_out = nn.Conv2d(inner_dim, dim, 1, bias = False)
def forward(self, fmap):
h, x, y = self.heads, *fmap.shape[-2:]
fmap = self.norm(fmap)
q, k, v = self.to_qkv(fmap).chunk(3, dim = 1)
q, k, v = rearrange_many((q, k, v), 'b (h c) x y -> (b h) (x y) c', h = h)
q = q.softmax(dim = -1)
k = k.softmax(dim = -2)
q = q * self.scale
context = einsum('b n d, b n e -> b d e', k, v)
out = einsum('b n d, b d e -> b n e', q, context)
out = rearrange(out, '(b h) (x y) d -> b (h d) x y', h = h, x = x, y = y)
out = self.nonlin(out)
return self.to_out(out)
class Unet(nn.Module):
def __init__(
self,
@@ -1117,15 +1044,14 @@ class Unet(nn.Module):
dim_mults=(1, 2, 4, 8),
channels = 3,
attn_dim_head = 32,
attn_heads = 16,
attn_heads = 8,
lowres_cond = False, # for cascading diffusion - https://cascaded-diffusion.github.io/
sparse_attn = False,
sparse_attn_window = 8, # window size for sparse attention
attend_at_middle = True, # whether to have a layer of attention at the bottleneck (can turn off for higher resolution in cascading DDPM, before bringing in efficient attention)
cond_on_text_encodings = False,
max_text_len = 256,
cond_on_image_embeds = False,
init_dim = None,
init_conv_kernel_size = 7
):
super().__init__()
# save locals to take care of some hyperparameters for cascading DDPM
@@ -1143,45 +1069,28 @@ class Unet(nn.Module):
self.channels = channels
init_channels = channels if not lowres_cond else channels * 2 # in cascading diffusion, one concats the low resolution image, blurred, for conditioning the higher resolution synthesis
init_dim = default(init_dim, dim // 2)
assert (init_conv_kernel_size % 2) == 1
self.init_conv = nn.Conv2d(init_channels, init_dim, init_conv_kernel_size, padding = init_conv_kernel_size // 2)
dims = [init_dim, *map(lambda m: dim * m, dim_mults)]
dims = [init_channels, *map(lambda m: dim * m, dim_mults)]
in_out = list(zip(dims[:-1], dims[1:]))
# time, image embeddings, and optional text encoding
cond_dim = default(cond_dim, dim)
time_cond_dim = dim * 4
self.to_time_hiddens = nn.Sequential(
self.time_mlp = nn.Sequential(
SinusoidalPosEmb(dim),
nn.Linear(dim, time_cond_dim),
nn.GELU()
)
self.to_time_tokens = nn.Sequential(
nn.Linear(time_cond_dim, cond_dim * num_time_tokens),
nn.Linear(dim, dim * 4),
nn.GELU(),
nn.Linear(dim * 4, cond_dim * num_time_tokens),
Rearrange('b (r d) -> b r d', r = num_time_tokens)
)
self.to_time_cond = nn.Sequential(
nn.Linear(time_cond_dim, time_cond_dim)
)
self.image_to_cond = nn.Sequential(
nn.Linear(image_embed_dim, cond_dim * num_image_tokens),
Rearrange('b (n d) -> b n d', n = num_image_tokens)
) if image_embed_dim != cond_dim else nn.Identity()
# text encoding conditioning (optional)
self.text_to_cond = None
if cond_on_text_encodings:
self.text_to_cond = nn.LazyLinear(cond_dim) if not exists(text_embed_dim) else nn.Linear(text_embed_dim, cond_dim)
self.text_to_cond = nn.LazyLinear(cond_dim) if not exists(text_embed_dim) else nn.Linear(text_embed_dim, cond_dim)
# finer control over whether to condition on image embeddings and text encodings
# so one can have the latter unets in the cascading DDPMs only focus on super-resoluting
@@ -1192,8 +1101,6 @@ class Unet(nn.Module):
# for classifier free guidance
self.null_image_embed = nn.Parameter(torch.randn(1, num_image_tokens, cond_dim))
self.max_text_len = max_text_len
self.null_text_embed = nn.Parameter(torch.randn(1, max_text_len, cond_dim))
# attention related params
@@ -1212,26 +1119,26 @@ class Unet(nn.Module):
layer_cond_dim = cond_dim if not is_first else None
self.downs.append(nn.ModuleList([
ConvNextBlock(dim_in, dim_out, time_cond_dim = time_cond_dim, norm = ind != 0),
Residual(LinearAttention(dim_out, **attn_kwargs)) if sparse_attn else nn.Identity(),
ConvNextBlock(dim_out, dim_out, cond_dim = layer_cond_dim, time_cond_dim = time_cond_dim),
ConvNextBlock(dim_in, dim_out, norm = ind != 0),
Residual(GridAttention(dim_out, window_size = sparse_attn_window, **attn_kwargs)) if sparse_attn else nn.Identity(),
ConvNextBlock(dim_out, dim_out, cond_dim = layer_cond_dim),
Downsample(dim_out) if not is_last else nn.Identity()
]))
mid_dim = dims[-1]
self.mid_block1 = ConvNextBlock(mid_dim, mid_dim, cond_dim = cond_dim, time_cond_dim = time_cond_dim)
self.mid_block1 = ConvNextBlock(mid_dim, mid_dim, cond_dim = cond_dim)
self.mid_attn = EinopsToAndFrom('b c h w', 'b (h w) c', Residual(Attention(mid_dim, **attn_kwargs))) if attend_at_middle else None
self.mid_block2 = ConvNextBlock(mid_dim, mid_dim, cond_dim = cond_dim, time_cond_dim = time_cond_dim)
self.mid_block2 = ConvNextBlock(mid_dim, mid_dim, cond_dim = cond_dim)
for ind, (dim_in, dim_out) in enumerate(reversed(in_out[1:])):
is_last = ind >= (num_resolutions - 2)
layer_cond_dim = cond_dim if not is_last else None
self.ups.append(nn.ModuleList([
ConvNextBlock(dim_out * 2, dim_in, cond_dim = layer_cond_dim, time_cond_dim = time_cond_dim),
Residual(LinearAttention(dim_in, **attn_kwargs)) if sparse_attn else nn.Identity(),
ConvNextBlock(dim_in, dim_in, cond_dim = layer_cond_dim, time_cond_dim = time_cond_dim),
ConvNextBlock(dim_out * 2, dim_in, cond_dim = layer_cond_dim),
Residual(GridAttention(dim_in, window_size = sparse_attn_window, **attn_kwargs)) if sparse_attn else nn.Identity(),
ConvNextBlock(dim_in, dim_in, cond_dim = layer_cond_dim),
Upsample(dim_in)
]))
@@ -1267,7 +1174,7 @@ class Unet(nn.Module):
if cond_scale == 1:
return logits
null_logits = self.forward(*args, text_cond_drop_prob = 1., image_cond_drop_prob = 1., **kwargs)
null_logits = self.forward(*args, cond_drop_prob = 1., **kwargs)
return null_logits + (logits - null_logits) * cond_scale
def forward(
@@ -1278,9 +1185,7 @@ class Unet(nn.Module):
image_embed,
lowres_cond_img = None,
text_encodings = None,
text_mask = None,
image_cond_drop_prob = 0.,
text_cond_drop_prob = 0.,
cond_drop_prob = 0.,
blur_sigma = None,
blur_kernel_size = None
):
@@ -1293,23 +1198,14 @@ class Unet(nn.Module):
if exists(lowres_cond_img):
x = torch.cat((x, lowres_cond_img), dim = 1)
# initial convolution
x = self.init_conv(x)
# time conditioning
time_hiddens = self.to_time_hiddens(time)
time_tokens = self.to_time_tokens(time_hiddens)
t = self.to_time_cond(time_hiddens)
time_tokens = self.time_mlp(time)
# conditional dropout
image_keep_mask = prob_mask_like((batch_size,), 1 - image_cond_drop_prob, device = device)
text_keep_mask = prob_mask_like((batch_size,), 1 - text_cond_drop_prob, device = device)
image_keep_mask, text_keep_mask = rearrange_many((image_keep_mask, text_keep_mask), 'b -> b 1 1')
cond_prob_mask = prob_mask_like((batch_size,), cond_drop_prob, device = device)
cond_prob_mask = rearrange(cond_prob_mask, 'b -> b 1 1')
# mask out image embedding depending on condition dropout
# for classifier free guidance
@@ -1320,7 +1216,7 @@ class Unet(nn.Module):
image_tokens = self.image_to_cond(image_embed)
image_tokens = torch.where(
image_keep_mask,
cond_prob_mask,
image_tokens,
self.null_image_embed
)
@@ -1331,25 +1227,10 @@ class Unet(nn.Module):
if exists(text_encodings) and self.cond_on_text_encodings:
text_tokens = self.text_to_cond(text_encodings)
text_tokens = text_tokens[:, :self.max_text_len]
text_tokens_len = text_tokens.shape[1]
remainder = self.max_text_len - text_tokens_len
if remainder > 0:
text_tokens = F.pad(text_tokens, (0, 0, 0, remainder))
if exists(text_mask):
if remainder > 0:
text_mask = F.pad(text_mask, (0, remainder), value = False)
text_mask = rearrange(text_mask, 'b n -> b n 1')
text_keep_mask = text_mask & text_keep_mask
text_tokens = torch.where(
text_keep_mask,
cond_prob_mask,
text_tokens,
self.null_text_embed
self.null_text_embed[:, :text_tokens.shape[1]]
)
# main conditioning tokens (c)
@@ -1369,24 +1250,24 @@ class Unet(nn.Module):
hiddens = []
for convnext, sparse_attn, convnext2, downsample in self.downs:
x = convnext(x, c, t)
x = convnext(x, c)
x = sparse_attn(x)
x = convnext2(x, c, t)
x = convnext2(x, c)
hiddens.append(x)
x = downsample(x)
x = self.mid_block1(x, mid_c, t)
x = self.mid_block1(x, mid_c)
if exists(self.mid_attn):
x = self.mid_attn(x)
x = self.mid_block2(x, mid_c, t)
x = self.mid_block2(x, mid_c)
for convnext, sparse_attn, convnext2, upsample in self.ups:
x = torch.cat((x, hiddens.pop()), dim=1)
x = convnext(x, c, t)
x = convnext(x, c)
x = sparse_attn(x)
x = convnext2(x, c, t)
x = convnext2(x, c)
x = upsample(x)
return self.final_conv(x)
@@ -1437,8 +1318,7 @@ class Decoder(BaseGaussianDiffusion):
clip,
vae = tuple(),
timesteps = 1000,
image_cond_drop_prob = 0.1,
text_cond_drop_prob = 0.5,
cond_drop_prob = 0.2,
loss_type = 'l1',
beta_schedule = 'cosine',
predict_x_start = False,
@@ -1449,8 +1329,6 @@ class Decoder(BaseGaussianDiffusion):
blur_sigma = 0.1, # cascading ddpm - blur sigma
blur_kernel_size = 3, # cascading ddpm - blur kernel size
condition_on_text_encodings = False, # the paper suggested that this didn't do much in the decoder, but i'm allowing the option for experimentation
clip_denoised = True,
clip_x_start = True
):
super().__init__(
beta_schedule = beta_schedule,
@@ -1524,13 +1402,7 @@ class Decoder(BaseGaussianDiffusion):
# classifier free guidance
self.image_cond_drop_prob = image_cond_drop_prob
self.text_cond_drop_prob = text_cond_drop_prob
# whether to clip when sampling
self.clip_denoised = clip_denoised
self.clip_x_start = clip_x_start
self.cond_drop_prob = cond_drop_prob
def get_unet(self, unet_number):
assert 0 < unet_number <= len(self.unets)
@@ -1557,31 +1429,31 @@ class Decoder(BaseGaussianDiffusion):
image_embed, _ = self.clip.embed_image(image)
return image_embed
def p_mean_variance(self, unet, x, t, image_embed, text_encodings = None, text_mask = None, lowres_cond_img = None, clip_denoised = True, predict_x_start = False, cond_scale = 1.):
pred = unet.forward_with_cond_scale(x, t, image_embed = image_embed, text_encodings = text_encodings, text_mask = text_mask, cond_scale = cond_scale, lowres_cond_img = lowres_cond_img)
def p_mean_variance(self, unet, x, t, image_embed, text_encodings = None, lowres_cond_img = None, clip_denoised = True, predict_x_start = False, cond_scale = 1.):
pred = unet.forward_with_cond_scale(x, t, image_embed = image_embed, text_encodings = text_encodings, cond_scale = cond_scale, lowres_cond_img = lowres_cond_img)
if predict_x_start:
x_recon = pred
else:
x_recon = self.predict_start_from_noise(x, t = t, noise = pred)
if clip_denoised:
if clip_denoised and not predict_x_start:
x_recon.clamp_(-1., 1.)
model_mean, posterior_variance, posterior_log_variance = self.q_posterior(x_start=x_recon, x_t=x, t=t)
return model_mean, posterior_variance, posterior_log_variance
@torch.no_grad()
def p_sample(self, unet, x, t, image_embed, text_encodings = None, text_mask = None, cond_scale = 1., lowres_cond_img = None, predict_x_start = False, clip_denoised = True, repeat_noise = False):
def p_sample(self, unet, x, t, image_embed, text_encodings = None, cond_scale = 1., lowres_cond_img = None, predict_x_start = False, clip_denoised = True, repeat_noise = False):
b, *_, device = *x.shape, x.device
model_mean, _, model_log_variance = self.p_mean_variance(unet, x = x, t = t, image_embed = image_embed, text_encodings = text_encodings, text_mask = text_mask, cond_scale = cond_scale, lowres_cond_img = lowres_cond_img, clip_denoised = clip_denoised, predict_x_start = predict_x_start)
model_mean, _, model_log_variance = self.p_mean_variance(unet, x = x, t = t, image_embed = image_embed, text_encodings = text_encodings, cond_scale = cond_scale, lowres_cond_img = lowres_cond_img, clip_denoised = clip_denoised, predict_x_start = predict_x_start)
noise = noise_like(x.shape, device, repeat_noise)
# no noise when t == 0
nonzero_mask = (1 - (t == 0).float()).reshape(b, *((1,) * (len(x.shape) - 1)))
return model_mean + nonzero_mask * (0.5 * model_log_variance).exp() * noise
@torch.no_grad()
def p_sample_loop(self, unet, shape, image_embed, predict_x_start = False, clip_denoised = True, lowres_cond_img = None, text_encodings = None, text_mask = None, cond_scale = 1):
def p_sample_loop(self, unet, shape, image_embed, predict_x_start = False, lowres_cond_img = None, text_encodings = None, cond_scale = 1):
device = self.betas.device
b = shape[0]
@@ -1594,16 +1466,14 @@ class Decoder(BaseGaussianDiffusion):
torch.full((b,), i, device = device, dtype = torch.long),
image_embed = image_embed,
text_encodings = text_encodings,
text_mask = text_mask,
cond_scale = cond_scale,
lowres_cond_img = lowres_cond_img,
predict_x_start = predict_x_start,
clip_denoised = clip_denoised
predict_x_start = predict_x_start
)
return img
def p_losses(self, unet, x_start, times, *, image_embed, lowres_cond_img = None, text_encodings = None, text_mask = None, predict_x_start = False, noise = None):
def p_losses(self, unet, x_start, times, *, image_embed, lowres_cond_img = None, text_encodings = None, predict_x_start = False, noise = None):
noise = default(noise, lambda: torch.randn_like(x_start))
x_noisy = self.q_sample(x_start = x_start, t = times, noise = noise)
@@ -1613,10 +1483,8 @@ class Decoder(BaseGaussianDiffusion):
times,
image_embed = image_embed,
text_encodings = text_encodings,
text_mask = text_mask,
lowres_cond_img = lowres_cond_img,
image_cond_drop_prob = self.image_cond_drop_prob,
text_cond_drop_prob = self.text_cond_drop_prob,
cond_drop_prob = self.cond_drop_prob
)
target = noise if not predict_x_start else x_start
@@ -1626,25 +1494,19 @@ class Decoder(BaseGaussianDiffusion):
@torch.no_grad()
@eval_decorator
def sample(
self,
image_embed,
text = None,
cond_scale = 1.,
stop_at_unet_number = None
):
def sample(self, image_embed, text = None, cond_scale = 1.):
batch_size = image_embed.shape[0]
text_encodings = text_mask = None
text_encodings = None
if exists(text):
_, text_encodings, text_mask = self.clip.embed_text(text)
_, text_encodings, _ = self.clip.embed_text(text)
assert not (self.condition_on_text_encodings and not exists(text_encodings)), 'text or text encodings must be passed into decoder if specified'
assert not (not self.condition_on_text_encodings and exists(text_encodings)), 'decoder specified not to be conditioned on text, yet it is presented'
img = None
for unet_number, unet, vae, channel, image_size, predict_x_start in tqdm(zip(range(1, len(self.unets) + 1), self.unets, self.vaes, self.sample_channels, self.image_sizes, self.predict_x_start)):
for unet, vae, channel, image_size, predict_x_start in tqdm(zip(self.unets, self.vaes, self.sample_channels, self.image_sizes, self.predict_x_start)):
context = self.one_unet_in_gpu(unet = unet) if image_embed.is_cuda else null_context()
@@ -1655,7 +1517,6 @@ class Decoder(BaseGaussianDiffusion):
if unet.lowres_cond:
lowres_cond_img = self.to_lowres_cond(img, target_image_size = image_size)
is_latent_diffusion = isinstance(vae, VQGanVAE)
image_size = vae.get_encoded_fmap_size(image_size)
shape = (batch_size, vae.encoded_dim, image_size, image_size)
@@ -1667,18 +1528,13 @@ class Decoder(BaseGaussianDiffusion):
shape,
image_embed = image_embed,
text_encodings = text_encodings,
text_mask = text_mask,
cond_scale = cond_scale,
predict_x_start = predict_x_start,
clip_denoised = not is_latent_diffusion,
lowres_cond_img = lowres_cond_img
)
img = vae.decode(img)
if exists(stop_at_unet_number) and stop_at_unet_number == unet_number:
break
return img
def forward(
@@ -1709,9 +1565,9 @@ class Decoder(BaseGaussianDiffusion):
if not exists(image_embed):
image_embed, _ = self.clip.embed_image(image)
text_encodings = text_mask = None
text_encodings = None
if exists(text) and not exists(text_encodings):
_, text_encodings, text_mask = self.clip.embed_text(text)
_, text_encodings, _ = self.clip.embed_text(text)
assert not (self.condition_on_text_encodings and not exists(text_encodings)), 'text or text encodings must be passed into decoder if specified'
assert not (not self.condition_on_text_encodings and exists(text_encodings)), 'decoder specified not to be conditioned on text, yet it is presented'
@@ -1726,7 +1582,7 @@ class Decoder(BaseGaussianDiffusion):
if exists(lowres_cond_img):
lowres_cond_img = vae.encode(lowres_cond_img)
return self.p_losses(unet, image, times, image_embed = image_embed, text_encodings = text_encodings, text_mask = text_mask, lowres_cond_img = lowres_cond_img, predict_x_start = predict_x_start)
return self.p_losses(unet, image, times, image_embed = image_embed, text_encodings = text_encodings, lowres_cond_img = lowres_cond_img, predict_x_start = predict_x_start)
# main class
@@ -1776,3 +1632,4 @@ class DALLE2(nn.Module):
return images[0]
return images

View File

@@ -0,0 +1,84 @@
import torch
from PIL import Image
from dalle2_pytorch.dalle2_pytorch import BaseClipAdapter
import torchvision.transforms as T
def find_layer(model, layer):
modules = dict([*model.named_modules()])
return modules.get(layer, None)
def hook(_, input, output):
print(output.shape)
import clip
# image = preprocess(Image.open("CLIP.png")).unsqueeze(0).to(device)
text = clip.tokenize(["a diagram", "a dog", "a cat"]).cuda()
image = torch.randn(1, 3, 224, 224).cuda()
class OpenAIClipAdapter(BaseClipAdapter):
def __init__(self, name = 'ViT-B/32'):
try:
import clip
except ImportError:
print('you must install openai clip in order to use this adapter - `pip install git+https://github.com/openai/CLIP.git` - more instructions at https://github.com/openai/CLIP#usage')
openai_clip, _ = clip.load(name)
super().__init__(openai_clip)
text_attention_final = self.find_layer(self.clip, 'ln_final')
self.handle = text_attention_final.register_forward_hook(self._hook)
self.clip_normalize = T.Normalize((0.48145466, 0.4578275, 0.40821073), (0.26862954, 0.26130258, 0.27577711))
self.cleared = False
def find_layer(self, layer):
modules = dict([*self.clip.named_modules()])
return modules.get(layer, None)
def clear(self):
if self.cleared:
return
self.handle()
def _hook(self, _, inputs, outputs):
self.text_encodings = outputs
@property
def dim_latent(self):
return 512
@property
def image_size(self):
return self.clip.visual.input_resolution
@property
def image_channels(self):
return 3
@torch.no_grad()
def embed_text(self, text):
assert not self.cleared
text_embed = self.clip.encode_text(text)
text_encodings = self.text_encodings
del self.text_encodings
return text_embed, text_encodings
@torch.no_grad()
def embed_image(self, image):
assert not self.cleared
image = self.clip_normalize(image)
image_embed = self.clip.encode_image(image)
return image_embed, None
clip_adapter = OpenAIClipAdapter().cuda()
# print(model)
with torch.no_grad():
image_features, _ = clip_adapter.embed_image(image)
text_features, text_encodings = clip_adapter.embed_text(text)
print(text_features.shape, image_features.shape)
print(text_encodings.shape)

View File

@@ -1,43 +1,6 @@
import copy
from functools import partial
import torch
from torch import nn
from torch.cuda.amp import autocast, GradScaler
from dalle2_pytorch.dalle2_pytorch import Decoder
from dalle2_pytorch.optimizer import get_optimizer
# helper functions
def exists(val):
return val is not None
def cast_tuple(val, length = 1):
return val if isinstance(val, tuple) else ((val,) * length)
def pick_and_pop(keys, d):
values = list(map(lambda key: d.pop(key), keys))
return dict(zip(keys, values))
def group_dict_by_key(cond, d):
return_val = [dict(),dict()]
for key in d.keys():
match = bool(cond(key))
ind = int(not match)
return_val[ind][key] = d[key]
return (*return_val,)
def string_begins_with(prefix, str):
return str.startswith(prefix)
def group_by_key_prefix(prefix, d):
return group_dict_by_key(partial(string_begins_with, prefix), d)
def groupby_prefix_and_trim(prefix, d):
kwargs_with_prefix, kwargs = group_dict_by_key(partial(string_begins_with, prefix), d)
kwargs_without_prefix = dict(map(lambda x: (x[0][len(prefix):], x[1]), tuple(kwargs_with_prefix.items())))
return kwargs_without_prefix, kwargs
# exponential moving average wrapper
@@ -46,16 +9,16 @@ class EMA(nn.Module):
self,
model,
beta = 0.99,
update_after_step = 1000,
update_every = 10,
ema_update_after_step = 1000,
ema_update_every = 10,
):
super().__init__()
self.beta = beta
self.online_model = model
self.ema_model = copy.deepcopy(model)
self.update_after_step = update_after_step # only start EMA after this step number, starting at 0
self.update_every = update_every
self.ema_update_after_step = ema_update_after_step # only start EMA after this step number, starting at 0
self.ema_update_every = ema_update_every
self.register_buffer('initted', torch.Tensor([False]))
self.register_buffer('step', torch.tensor([0.]))
@@ -63,7 +26,7 @@ class EMA(nn.Module):
def update(self):
self.step += 1
if self.step <= self.update_after_step or (self.step % self.update_every) != 0:
if self.step <= self.ema_update_after_step or (self.step % self.ema_update_every) != 0:
return
if not self.initted:
@@ -88,112 +51,3 @@ class EMA(nn.Module):
def __call__(self, *args, **kwargs):
return self.ema_model(*args, **kwargs)
# trainers
class DecoderTrainer(nn.Module):
def __init__(
self,
decoder,
use_ema = True,
lr = 3e-4,
wd = 1e-2,
max_grad_norm = None,
amp = False,
**kwargs
):
super().__init__()
assert isinstance(decoder, Decoder)
ema_kwargs, kwargs = groupby_prefix_and_trim('ema_', kwargs)
self.decoder = decoder
self.num_unets = len(self.decoder.unets)
self.use_ema = use_ema
if use_ema:
has_lazy_linear = any([type(module) == nn.LazyLinear for module in decoder.modules()])
assert not has_lazy_linear, 'you must set the text_embed_dim on your u-nets if you plan on doing automatic exponential moving average'
self.ema_unets = nn.ModuleList([])
self.amp = amp
# be able to finely customize learning rate, weight decay
# per unet
lr, wd = map(partial(cast_tuple, length = self.num_unets), (lr, wd))
for ind, (unet, unet_lr, unet_wd) in enumerate(zip(self.decoder.unets, lr, wd)):
optimizer = get_optimizer(
unet.parameters(),
lr = unet_lr,
wd = unet_wd,
**kwargs
)
setattr(self, f'optim{ind}', optimizer) # cannot use pytorch ModuleList for some reason with optimizers
if self.use_ema:
self.ema_unets.append(EMA(unet, **ema_kwargs))
scaler = GradScaler(enabled = amp)
setattr(self, f'scaler{ind}', scaler)
# gradient clipping if needed
self.max_grad_norm = max_grad_norm
@property
def unets(self):
return nn.ModuleList([ema.ema_model for ema in self.ema_unets])
def scale(self, loss, *, unet_number):
assert 1 <= unet_number <= self.num_unets
index = unet_number - 1
scaler = getattr(self, f'scaler{index}')
return scaler.scale(loss)
def update(self, unet_number):
assert 1 <= unet_number <= self.num_unets
index = unet_number - 1
unet = self.decoder.unets[index]
optimizer = getattr(self, f'optim{index}')
scaler = getattr(self, f'scaler{index}')
if exists(self.max_grad_norm):
scaler.unscale_(optimizer)
nn.utils.clip_grad_norm_(unet.parameters(), self.max_grad_norm)
scaler.step(optimizer)
scaler.update()
optimizer.zero_grad()
if self.use_ema:
ema_unet = self.ema_unets[index]
ema_unet.update()
@torch.no_grad()
def sample(self, *args, **kwargs):
if self.use_ema:
trainable_unets = self.decoder.unets
self.decoder.unets = self.unets # swap in exponential moving averaged unets for sampling
output = self.decoder.sample(*args, **kwargs)
if self.use_ema:
self.decoder.unets = trainable_unets # restore original training unets
return output
def forward(
self,
x,
*,
unet_number,
divisor = 1,
**kwargs
):
with autocast(enabled = self.amp):
loss = self.decoder(x, unet_number = unet_number, **kwargs)
return self.scale(loss / divisor, unet_number = unet_number)

View File

@@ -1,266 +0,0 @@
from math import sqrt
import copy
from random import choice
from pathlib import Path
from shutil import rmtree
import torch
from torch import nn
from PIL import Image
from torchvision.datasets import ImageFolder
import torchvision.transforms as T
from torch.utils.data import Dataset, DataLoader, random_split
from torchvision.utils import make_grid, save_image
from einops import rearrange
from dalle2_pytorch.train import EMA
from dalle2_pytorch.vqgan_vae import VQGanVAE
from dalle2_pytorch.optimizer import get_optimizer
# helpers
def exists(val):
return val is not None
def noop(*args, **kwargs):
pass
def cycle(dl):
while True:
for data in dl:
yield data
def cast_tuple(t):
return t if isinstance(t, (tuple, list)) else (t,)
def yes_or_no(question):
answer = input(f'{question} (y/n) ')
return answer.lower() in ('yes', 'y')
def accum_log(log, new_logs):
for key, new_value in new_logs.items():
old_value = log.get(key, 0.)
log[key] = old_value + new_value
return log
# classes
class ImageDataset(Dataset):
def __init__(
self,
folder,
image_size,
exts = ['jpg', 'jpeg', 'png']
):
super().__init__()
self.folder = folder
self.image_size = image_size
self.paths = [p for ext in exts for p in Path(f'{folder}').glob(f'**/*.{ext}')]
print(f'{len(self.paths)} training samples found at {folder}')
self.transform = T.Compose([
T.Lambda(lambda img: img.convert('RGB') if img.mode != 'RGB' else img),
T.Resize(image_size),
T.RandomHorizontalFlip(),
T.CenterCrop(image_size),
T.ToTensor()
])
def __len__(self):
return len(self.paths)
def __getitem__(self, index):
path = self.paths[index]
img = Image.open(path)
return self.transform(img)
# main trainer class
class VQGanVAETrainer(nn.Module):
def __init__(
self,
vae,
*,
num_train_steps,
lr,
batch_size,
folder,
grad_accum_every,
wd = 0.,
save_results_every = 100,
save_model_every = 1000,
results_folder = './results',
valid_frac = 0.05,
random_split_seed = 42,
ema_beta = 0.995,
ema_update_after_step = 2000,
ema_update_every = 10,
apply_grad_penalty_every = 4,
):
super().__init__()
assert isinstance(vae, VQGanVAE), 'vae must be instance of VQGanVAE'
image_size = vae.image_size
self.vae = vae
self.ema_vae = EMA(vae, update_after_step = ema_update_after_step, update_every = ema_update_every)
self.register_buffer('steps', torch.Tensor([0]))
self.num_train_steps = num_train_steps
self.batch_size = batch_size
self.grad_accum_every = grad_accum_every
all_parameters = set(vae.parameters())
discr_parameters = set(vae.discr.parameters())
vae_parameters = all_parameters - discr_parameters
self.optim = get_optimizer(vae_parameters, lr = lr, wd = wd)
self.discr_optim = get_optimizer(discr_parameters, lr = lr, wd = wd)
# create dataset
self.ds = ImageDataset(folder, image_size = image_size)
# split for validation
if valid_frac > 0:
train_size = int((1 - valid_frac) * len(self.ds))
valid_size = len(self.ds) - train_size
self.ds, self.valid_ds = random_split(self.ds, [train_size, valid_size], generator = torch.Generator().manual_seed(random_split_seed))
print(f'training with dataset of {len(self.ds)} samples and validating with randomly splitted {len(self.valid_ds)} samples')
else:
self.valid_ds = self.ds
print(f'training with shared training and valid dataset of {len(self.ds)} samples')
# dataloader
self.dl = cycle(DataLoader(
self.ds,
batch_size = batch_size,
shuffle = True
))
self.valid_dl = cycle(DataLoader(
self.valid_ds,
batch_size = batch_size,
shuffle = True
))
self.save_model_every = save_model_every
self.save_results_every = save_results_every
self.apply_grad_penalty_every = apply_grad_penalty_every
self.results_folder = Path(results_folder)
if len([*self.results_folder.glob('**/*')]) > 0 and yes_or_no('do you want to clear previous experiment checkpoints and results?'):
rmtree(str(self.results_folder))
self.results_folder.mkdir(parents = True, exist_ok = True)
def train_step(self):
device = next(self.vae.parameters()).device
steps = int(self.steps.item())
apply_grad_penalty = not (steps % self.apply_grad_penalty_every)
self.vae.train()
# logs
logs = {}
# update vae (generator)
for _ in range(self.grad_accum_every):
img = next(self.dl)
img = img.to(device)
loss = self.vae(
img,
return_loss = True,
apply_grad_penalty = apply_grad_penalty
)
accum_log(logs, {'loss': loss.item() / self.grad_accum_every})
(loss / self.grad_accum_every).backward()
self.optim.step()
self.optim.zero_grad()
# update discriminator
if exists(self.vae.discr):
discr_loss = 0
for _ in range(self.grad_accum_every):
img = next(self.dl)
img = img.to(device)
loss = self.vae(img, return_discr_loss = True)
accum_log(logs, {'discr_loss': loss.item() / self.grad_accum_every})
(loss / self.grad_accum_every).backward()
self.discr_optim.step()
self.discr_optim.zero_grad()
# log
print(f"{steps}: vae loss: {logs['loss']} - discr loss: {logs['discr_loss']}")
# update exponential moving averaged generator
self.ema_vae.update()
# sample results every so often
if not (steps % self.save_results_every):
for model, filename in ((self.ema_vae.ema_model, f'{steps}.ema'), (self.vae, str(steps))):
model.eval()
imgs = next(self.dl)
imgs = imgs.to(device)
recons = model(imgs)
nrows = int(sqrt(self.batch_size))
imgs_and_recons = torch.stack((imgs, recons), dim = 0)
imgs_and_recons = rearrange(imgs_and_recons, 'r b ... -> (b r) ...')
imgs_and_recons = imgs_and_recons.detach().cpu().float().clamp(0., 1.)
grid = make_grid(imgs_and_recons, nrow = 2, normalize = True, value_range = (0, 1))
logs['reconstructions'] = grid
save_image(grid, str(self.results_folder / f'{filename}.png'))
print(f'{steps}: saving to {str(self.results_folder)}')
# save model every so often
if not (steps % self.save_model_every):
state_dict = self.vae.state_dict()
model_path = str(self.results_folder / f'vae.{steps}.pt')
torch.save(state_dict, model_path)
ema_state_dict = self.ema_vae.state_dict()
model_path = str(self.results_folder / f'vae.{steps}.ema.pt')
torch.save(ema_state_dict, model_path)
print(f'{steps}: saving model to {str(self.results_folder)}')
self.steps += 1
return logs
def train(self, log_fn = noop):
device = next(self.vae.parameters()).device
while self.steps < self.num_train_steps:
logs = self.train_step()
log_fn(logs)
print('training complete')

View File

@@ -285,10 +285,6 @@ class ResnetEncDec(nn.Module):
def get_encoded_fmap_size(self, image_size):
return image_size // (2 ** self.layers)
@property
def last_dec_layer(self):
return self.decoders[-1].weight
def encode(self, x):
for enc in self.encoders:
x = enc(x)
@@ -331,112 +327,6 @@ class ResBlock(nn.Module):
def forward(self, x):
return self.net(x) + x
# convnext enc dec
class ChanLayerNorm(nn.Module):
def __init__(self, dim, eps = 1e-5):
super().__init__()
self.eps = eps
self.g = nn.Parameter(torch.ones(1, dim, 1, 1))
def forward(self, x):
var = torch.var(x, dim = 1, unbiased = False, keepdim = True)
mean = torch.mean(x, dim = 1, keepdim = True)
return (x - mean) / (var + self.eps).sqrt() * self.g
class ConvNext(nn.Module):
def __init__(self, dim, mult = 4, kernel_size = 3, ds_kernel_size = 7):
super().__init__()
inner_dim = int(dim * mult)
self.net = nn.Sequential(
nn.Conv2d(dim, dim, ds_kernel_size, padding = ds_kernel_size // 2, groups = dim),
ChanLayerNorm(dim),
nn.Conv2d(dim, inner_dim, kernel_size, padding = kernel_size // 2),
nn.GELU(),
nn.Conv2d(inner_dim, dim, kernel_size, padding = kernel_size // 2)
)
def forward(self, x):
return self.net(x) + x
class ConvNextEncDec(nn.Module):
def __init__(
self,
dim,
*,
channels = 3,
layers = 4,
layer_mults = None,
num_blocks = 1,
first_conv_kernel_size = 5,
use_attn = True,
attn_dim_head = 64,
attn_heads = 8,
attn_dropout = 0.,
):
super().__init__()
self.layers = layers
self.encoders = MList([])
self.decoders = MList([])
layer_mults = default(layer_mults, list(map(lambda t: 2 ** t, range(layers))))
assert len(layer_mults) == layers, 'layer multipliers must be equal to designated number of layers'
layer_dims = [dim * mult for mult in layer_mults]
dims = (dim, *layer_dims)
self.encoded_dim = dims[-1]
dim_pairs = zip(dims[:-1], dims[1:])
append = lambda arr, t: arr.append(t)
prepend = lambda arr, t: arr.insert(0, t)
if not isinstance(num_blocks, tuple):
num_blocks = (*((0,) * (layers - 1)), num_blocks)
if not isinstance(use_attn, tuple):
use_attn = (*((False,) * (layers - 1)), use_attn)
assert len(num_blocks) == layers, 'number of blocks config must be equal to number of layers'
assert len(use_attn) == layers
for layer_index, (dim_in, dim_out), layer_num_blocks, layer_use_attn in zip(range(layers), dim_pairs, num_blocks, use_attn):
append(self.encoders, nn.Sequential(nn.Conv2d(dim_in, dim_out, 4, stride = 2, padding = 1), leaky_relu()))
prepend(self.decoders, nn.Sequential(nn.ConvTranspose2d(dim_out, dim_in, 4, 2, 1), leaky_relu()))
if layer_use_attn:
prepend(self.decoders, VQGanAttention(dim = dim_out, heads = attn_heads, dim_head = attn_dim_head, dropout = attn_dropout))
for _ in range(layer_num_blocks):
append(self.encoders, ConvNext(dim_out))
prepend(self.decoders, ConvNext(dim_out))
if layer_use_attn:
append(self.encoders, VQGanAttention(dim = dim_out, heads = attn_heads, dim_head = attn_dim_head, dropout = attn_dropout))
prepend(self.encoders, nn.Conv2d(channels, dim, first_conv_kernel_size, padding = first_conv_kernel_size // 2))
append(self.decoders, nn.Conv2d(dim, channels, 1))
def get_encoded_fmap_size(self, image_size):
return image_size // (2 ** self.layers)
@property
def last_dec_layer(self):
return self.decoders[-1].weight
def encode(self, x):
for enc in self.encoders:
x = enc(x)
return x
def decode(self, x):
for dec in self.decoders:
x = dec(x)
return x
# vqgan attention layer
class VQGanAttention(nn.Module):
@@ -614,10 +504,6 @@ class ViTEncDec(nn.Module):
def get_encoded_fmap_size(self, image_size):
return image_size // self.patch_size
@property
def last_dec_layer(self):
return self.decoder[-3][-1].weight
def encode(self, x):
return self.encoder(x)
@@ -682,8 +568,6 @@ class VQGanVAE(nn.Module):
enc_dec_klass = ResnetEncDec
elif vae_type == 'vit':
enc_dec_klass = ViTEncDec
elif vae_type == 'convnext':
enc_dec_klass = ConvNextEncDec
else:
raise ValueError(f'{vae_type} not valid')
@@ -855,7 +739,7 @@ class VQGanVAE(nn.Module):
# calculate adaptive weight
last_dec_layer = self.enc_dec.last_dec_layer
last_dec_layer = self.decoders[-1].weight
norm_grad_wrt_gen_loss = grad_layer_wrt_loss(gen_loss, last_dec_layer).norm(p = 2)
norm_grad_wrt_perceptual_loss = grad_layer_wrt_loss(perceptual_loss, last_dec_layer).norm(p = 2)

View File

@@ -10,7 +10,7 @@ setup(
'dream = dalle2_pytorch.cli:dream'
],
},
version = '0.0.94',
version = '0.0.70',
license='MIT',
description = 'DALL-E 2',
author = 'Phil Wang',
@@ -23,17 +23,14 @@ setup(
],
install_requires=[
'click',
'clip-anytorch',
'einops>=0.4',
'einops-exts>=0.0.3',
'embedding-reader',
'kornia>=0.5.4',
'pillow',
'torch>=1.10',
'torchvision',
'tqdm',
'vector-quantize-pytorch',
'webdataset',
'x-clip>=0.5.1',
'youtokentome'
],

View File

@@ -1,250 +0,0 @@
import os
import math
import argparse
import torch
from torch import nn
from embedding_reader import EmbeddingReader
from dalle2_pytorch import DiffusionPrior, DiffusionPriorNetwork
from dalle2_pytorch.optimizer import get_optimizer
from dalle2_pytorch.optimizer import get_optimizer
from torch.cuda.amp import autocast,GradScaler
import time
from tqdm import tqdm
import wandb
os.environ["WANDB_SILENT"] = "true"
def eval_model(model,device,image_reader,text_reader,start,end,batch_size,loss_type,phase="Validation"):
model.eval()
with torch.no_grad():
total_loss = 0.
total_samples = 0.
for emb_images, emb_text in zip(image_reader(batch_size=batch_size, start=start, end=end),
text_reader(batch_size=batch_size, start=start, end=end)):
emb_images_tensor = torch.tensor(emb_images[0]).to(device)
emb_text_tensor = torch.tensor(emb_text[0]).to(device)
batches = emb_images_tensor.shape[0]
loss = model(text_embed = emb_text_tensor, image_embed = emb_images_tensor)
total_loss += loss.item() * batches
total_samples += batches
avg_loss = (total_loss / total_samples)
wandb.log({f'{phase} {loss_type}': avg_loss})
def save_model(save_path, state_dict):
# Saving State Dict
print("====================================== Saving checkpoint ======================================")
torch.save(state_dict, save_path+'/'+str(time.time())+'_saved_model.pth')
def train(image_embed_dim,
image_embed_url,
text_embed_url,
batch_size,
train_percent,
val_percent,
test_percent,
num_epochs,
dp_loss_type,
clip,
dp_condition_on_text_encodings,
dp_timesteps,
dp_l2norm_output,
dp_normformer,
dp_cond_drop_prob,
dpn_depth,
dpn_dim_head,
dpn_heads,
save_interval,
save_path,
device,
learning_rate=0.001,
max_grad_norm=0.5,
weight_decay=0.01,
amp=False):
# DiffusionPriorNetwork
prior_network = DiffusionPriorNetwork(
dim = image_embed_dim,
depth = dpn_depth,
dim_head = dpn_dim_head,
heads = dpn_heads,
normformer = dp_normformer,
l2norm_output = dp_l2norm_output).to(device)
# DiffusionPrior with text embeddings and image embeddings pre-computed
diffusion_prior = DiffusionPrior(
net = prior_network,
clip = clip,
image_embed_dim = image_embed_dim,
timesteps = dp_timesteps,
cond_drop_prob = dp_cond_drop_prob,
loss_type = dp_loss_type,
condition_on_text_encodings = dp_condition_on_text_encodings).to(device)
# Get image and text embeddings from the servers
print("==============Downloading embeddings - image and text====================")
image_reader = EmbeddingReader(embeddings_folder=image_embed_url, file_format="npy")
text_reader = EmbeddingReader(embeddings_folder=text_embed_url, file_format="npy")
num_data_points = text_reader.count
# Create save_path if it doesn't exist
if not os.path.exists(save_path):
os.makedirs(save_path)
### Training code ###
scaler = GradScaler(enabled=amp)
optimizer = get_optimizer(diffusion_prior.net.parameters(), wd=weight_decay, lr=learning_rate)
epochs = num_epochs
step = 0
t = time.time()
train_set_size = int(train_percent*num_data_points)
val_set_size = int(val_percent*num_data_points)
for _ in range(epochs):
diffusion_prior.train()
for emb_images,emb_text in zip(image_reader(batch_size=batch_size, start=0, end=train_set_size),
text_reader(batch_size=batch_size, start=0, end=train_set_size)):
emb_images_tensor = torch.tensor(emb_images[0]).to(device)
emb_text_tensor = torch.tensor(emb_text[0]).to(device)
with autocast(enabled=amp):
loss = diffusion_prior(text_embed = emb_text_tensor,image_embed = emb_images_tensor)
scaler.scale(loss).backward()
# Samples per second
step+=1
samples_per_sec = batch_size*step/(time.time()-t)
# Save checkpoint every save_interval minutes
if(int(time.time()-t) >= 60*save_interval):
t = time.time()
save_model(
save_path,
dict(model=diffusion_prior.state_dict(), optimizer=optimizer.state_dict(), scaler=scaler.state_dict()))
# Log to wandb
wandb.log({"Training loss": loss.item(),
"Steps": step,
"Samples per second": samples_per_sec})
scaler.unscale_(optimizer)
nn.utils.clip_grad_norm_(diffusion_prior.parameters(), max_grad_norm)
scaler.step(optimizer)
scaler.update()
optimizer.zero_grad()
### Evaluate model(validation run) ###
start = train_set_size
end=start+val_set_size
eval_model(diffusion_prior,device,image_reader,text_reader,start,end,batch_size,dp_loss_type,phase="Validation")
### Test run ###
test_set_size = int(test_percent*train_set_size)
start=train_set_size+val_set_size
end=num_data_points
eval_model(diffusion_prior,device,image_reader,text_reader,start,end,batch_size,dp_loss_type,phase="Test")
def main():
parser = argparse.ArgumentParser()
# Logging
parser.add_argument("--wandb-entity", type=str, default="laion")
parser.add_argument("--wandb-project", type=str, default="diffusion-prior")
parser.add_argument("--wandb-name", type=str, default="laion-dprior")
parser.add_argument("--wandb-dataset", type=str, default="LAION-5B")
parser.add_argument("--wandb-arch", type=str, default="DiffusionPrior")
# URLs for embeddings
parser.add_argument("--image-embed-url", type=str, default="https://mystic.the-eye.eu/public/AI/cah/laion5b/embeddings/laion2B-en/img_emb/")
parser.add_argument("--text-embed-url", type=str, default="https://mystic.the-eye.eu/public/AI/cah/laion5b/embeddings/laion2B-en/text_emb/")
# Hyperparameters
parser.add_argument("--learning-rate", type=float, default=1.1e-4)
parser.add_argument("--weight-decay", type=float, default=6.02e-2)
parser.add_argument("--max-grad-norm", type=float, default=0.5)
parser.add_argument("--batch-size", type=int, default=10**4)
parser.add_argument("--num-epochs", type=int, default=5)
# Image embed dimension
parser.add_argument("--image-embed-dim", type=int, default=768)
# Train-test split
parser.add_argument("--train-percent", type=float, default=0.7)
parser.add_argument("--val-percent", type=float, default=0.2)
parser.add_argument("--test-percent", type=float, default=0.1)
# LAION training(pre-computed embeddings)
# DiffusionPriorNetwork(dpn) parameters
parser.add_argument("--dpn-depth", type=int, default=6)
parser.add_argument("--dpn-dim-head", type=int, default=64)
parser.add_argument("--dpn-heads", type=int, default=8)
# DiffusionPrior(dp) parameters
parser.add_argument("--dp-condition-on-text-encodings", type=bool, default=False)
parser.add_argument("--dp-timesteps", type=int, default=100)
parser.add_argument("--dp-l2norm-output", type=bool, default=False)
parser.add_argument("--dp-normformer", type=bool, default=False)
parser.add_argument("--dp-cond-drop-prob", type=float, default=0.1)
parser.add_argument("--dp-loss-type", type=str, default="l2")
parser.add_argument("--clip", type=str, default=None)
parser.add_argument("--amp", type=bool, default=False)
# Model checkpointing interval(minutes)
parser.add_argument("--save-interval", type=int, default=30)
parser.add_argument("--save-path", type=str, default="./diffusion_prior_checkpoints")
args = parser.parse_args()
print("Setting up wandb logging... Please wait...")
wandb.init(
entity=args.wandb_entity,
project=args.wandb_project,
config={
"learning_rate": args.learning_rate,
"architecture": args.wandb_arch,
"dataset": args.wandb_dataset,
"epochs": args.num_epochs,
})
print("wandb logging setup done!")
# Obtain the utilized device.
has_cuda = torch.cuda.is_available()
if has_cuda:
device = torch.device("cuda:0")
torch.cuda.set_device(device)
# Training loop
train(args.image_embed_dim,
args.image_embed_url,
args.text_embed_url,
args.batch_size,
args.train_percent,
args.val_percent,
args.test_percent,
args.num_epochs,
args.dp_loss_type,
args.clip,
args.dp_condition_on_text_encodings,
args.dp_timesteps,
args.dp_l2norm_output,
args.dp_normformer,
args.dp_cond_drop_prob,
args.dpn_depth,
args.dpn_dim_head,
args.dpn_heads,
args.save_interval,
args.save_path,
device,
args.learning_rate,
args.max_grad_norm,
args.weight_decay,
args.amp)
if __name__ == "__main__":
main()