Implémentation de Classifier Free Guidance dans Pytorch, en mettant l'accent sur le conditionnement du texte et la flexibilité d'inclure plusieurs modèles d'intégration de texte, comme cela est fait dans eDiff-I
Il est désormais clair que le guidage textuel constitue l’interface ultime avec les modèles. Ce référentiel exploitera la magie du décorateur Python pour faciliter l'intégration du conditionnement de texte SOTA à n'importe quel modèle.
StabilityAI pour son généreux parrainage, ainsi que mes autres sponsors
? Huggingface pour leur incroyable bibliothèque de transformateurs. Le module de conditionnement de texte utilisera les intégrations T5, comme le recommandent les dernières recherches.
OpenCLIP pour fournir des modèles CLIP open source SOTA. Le modèle eDiff voit d'immenses améliorations en combinant les intégrations T5 avec les intégrations de texte CLIP
$ pip install classifier-free-guidance-pytorch
import torch
from classifier_free_guidance_pytorch import TextConditioner
text_conditioner = TextConditioner (
model_types = 't5' ,
hidden_dims = ( 256 , 512 ),
hiddens_channel_first = False ,
cond_drop_prob = 0.2 # conditional dropout 20% of the time, must be greater than 0. to unlock classifier free guidance
). cuda ()
# pass in your text as a List[str], and get back a List[callable]
# each callable function receives the hiddens in the dimensions listed at init (hidden_dims)
first_condition_fn , second_condition_fn = text_conditioner ([ 'a dog chasing after a ball' ])
# these hiddens will be in the direct flow of your model, say in a unet
first_hidden = torch . randn ( 1 , 16 , 256 ). cuda ()
second_hidden = torch . randn ( 1 , 32 , 512 ). cuda ()
# conditioned features
first_conditioned = first_condition_fn ( first_hidden )
second_conditioned = second_condition_fn ( second_hidden )
Si vous souhaitez utiliser un conditionnement basé sur l'attention croisée (chaque fonctionnalité cachée de votre réseau peut s'occuper de jetons de sous-mots individuels), importez simplement AttentionTextConditioner
à la place. Le repos est pareil
from classifier_free_guidance_pytorch import AttentionTextConditioner
text_conditioner = AttentionTextConditioner (
model_types = ( 't5' , 'clip' ), # something like in eDiff paper, where they used both T5 and Clip for even better results (Balaji et al.)
hidden_dims = ( 256 , 512 ),
cond_drop_prob = 0.2
)
Il s'agit d'un travail en cours visant à rendre aussi simple que possible la conditionnalité textuelle de votre réseau.
Tout d’abord, disons que vous disposez d’un simple réseau à deux couches
import torch
from torch import nn
class MLP ( nn . Module ):
def __init__ (
self ,
dim
):
super (). __init__ ()
self . proj_in = nn . Sequential ( nn . Linear ( dim , dim * 2 ), nn . ReLU ())
self . proj_mid = nn . Sequential ( nn . Linear ( dim * 2 , dim ), nn . ReLU ())
self . proj_out = nn . Linear ( dim , 1 )
def forward (
self ,
data
):
hiddens1 = self . proj_in ( data )
hiddens2 = self . proj_mid ( hiddens1 )
return self . proj_out ( hiddens2 )
# instantiate model and pass in some data, get (in this case) a binary prediction
model = MLP ( dim = 256 )
data = torch . randn ( 2 , 256 )
pred = model ( data )
Vous souhaitez conditionner les calques cachés ( hiddens1
et hiddens2
) avec du texte. Chaque élément du lot obtiendrait ici son propre conditionnement de texte libre
Cela a été réduit à environ 3 étapes en utilisant ce référentiel.
import torch
from torch import nn
from classifier_free_guidance_pytorch import classifier_free_guidance_class_decorator
@ classifier_free_guidance_class_decorator
class MLP ( nn . Module ):
def __init__ ( self , dim ):
super (). __init__ ()
self . proj_in = nn . Sequential ( nn . Linear ( dim , dim * 2 ), nn . ReLU ())
self . proj_mid = nn . Sequential ( nn . Linear ( dim * 2 , dim ), nn . ReLU ())
self . proj_out = nn . Linear ( dim , 1 )
def forward (
self ,
inp ,
cond_fns # List[Callable] - (1) your forward function now receives a list of conditioning functions, which you invoke on your hidden tensors
):
cond_hidden1 , cond_hidden2 = cond_fns # conditioning functions are given back in the order of the `hidden_dims` set on the text conditioner
hiddens1 = self . proj_in ( inp )
hiddens1 = cond_hidden1 ( hiddens1 ) # (2) condition the first hidden layer with FiLM
hiddens2 = self . proj_mid ( hiddens1 )
hiddens2 = cond_hidden2 ( hiddens2 ) # condition the second hidden layer with FiLM
return self . proj_out ( hiddens2 )
# instantiate your model - extra keyword arguments will need to be defined, prepended by `text_condition_`
model = MLP (
dim = 256 ,
text_condition_type = 'film' , # can be film, attention, or null (none)
text_condition_model_types = ( 't5' , 'clip' ), # in this example, conditioning on both T5 and OpenCLIP
text_condition_hidden_dims = ( 512 , 256 ), # and pass in the hidden dimensions you would like to condition on. in this case there are two hidden dimensions (dim * 2 and dim, after the first and second projections)
text_condition_cond_drop_prob = 0.25 # conditional dropout probability for classifier free guidance. can be set to 0. if you do not need it and just want the text conditioning
)
# now you have your input data as well as corresponding free text as List[str]
data = torch . randn ( 2 , 256 )
texts = [ 'a description' , 'another description' ]
# (3) train your model, passing in your list of strings as 'texts'
pred = model ( data , texts = texts )
# after much training, you can now do classifier free guidance by passing in a condition scale of > 1. !
model . eval ()
guided_pred = model ( data , texts = texts , cond_scale = 3. , remove_parallel_component = True ) # cond_scale stands for conditioning scale from classifier free guidance paper
conditionnement complet du film, sans guidage sans classificateur (utilisé ici)
ajouter des conseils gratuits pour le conditionnement des films
conditionnement complet de l'attention croisée
test de résistance pour l'espace-temps dans une création vidéo
@article { Ho2022ClassifierFreeDG ,
title = { Classifier-Free Diffusion Guidance } ,
author = { Jonathan Ho } ,
journal = { ArXiv } ,
year = { 2022 } ,
volume = { abs/2207.12598 }
}
@article { Balaji2022eDiffITD ,
title = { eDiff-I: Text-to-Image Diffusion Models with an Ensemble of Expert Denoisers } ,
author = { Yogesh Balaji and Seungjun Nah and Xun Huang and Arash Vahdat and Jiaming Song and Karsten Kreis and Miika Aittala and Timo Aila and Samuli Laine and Bryan Catanzaro and Tero Karras and Ming-Yu Liu } ,
journal = { ArXiv } ,
year = { 2022 } ,
volume = { abs/2211.01324 }
}
@inproceedings { dao2022flashattention ,
title = { Flash{A}ttention: Fast and Memory-Efficient Exact Attention with {IO}-Awareness } ,
author = { Dao, Tri and Fu, Daniel Y. and Ermon, Stefano and Rudra, Atri and R{'e}, Christopher } ,
booktitle = { Advances in Neural Information Processing Systems } ,
year = { 2022 }
}
@inproceedings { Lin2023CommonDN ,
title = { Common Diffusion Noise Schedules and Sample Steps are Flawed } ,
author = { Shanchuan Lin and Bingchen Liu and Jiashi Li and Xiao Yang } ,
year = { 2023 }
}
@inproceedings { Chung2024CFGMC ,
title = { CFG++: Manifold-constrained Classifier Free Guidance for Diffusion Models } ,
author = { Hyungjin Chung and Jeongsol Kim and Geon Yeong Park and Hyelin Nam and Jong Chul Ye } ,
year = { 2024 } ,
url = { https://api.semanticscholar.org/CorpusID:270391454 }
}
@inproceedings { Sadat2024EliminatingOA ,
title = { Eliminating Oversaturation and Artifacts of High Guidance Scales in Diffusion Models } ,
author = { Seyedmorteza Sadat and Otmar Hilliges and Romann M. Weber } ,
year = { 2024 } ,
url = { https://api.semanticscholar.org/CorpusID:273098845 }
}