import torch
from diffusers import ImagePipelineOutput, PixArtAlphaPipeline, AutoencoderKL, Transformer2DModel, \
DPMSolverMultistepScheduler
from diffusers.image_processor import VaeImageProcessor
from diffusers.models.attention import BasicTransformerBlock
from diffusers.models.embeddings import PixArtAlphaTextProjection, PatchEmbed
from diffusers.models.normalization import AdaLayerNormSingle
from diffusers.pipelines.pixart_alpha.pipeline_pixart_alpha import retrieve_timesteps
from typing import Callable, List, Optional, Tuple, Union
from diffusers.utils import deprecate
from torch import nn
from transformers import T5Tokenizer, T5EncoderModel
ASPECT_RATIO_2048_BIN = {
"0.25": [1024.0, 4096.0],
"0.26": [1024.0, 3968.0],
"0.27": [1024.0, 3840.0],
"0.28": [1024.0, 3712.0],
"0.32": [1152.0, 3584.0],
"0.33": [1152.0, 3456.0],
"0.35": [1152.0, 3328.0],
"0.4": [1280.0, 3200.0],
"0.42": [1280.0, 3072.0],
"0.48": [1408.0, 2944.0],
"0.5": [1408.0, 2816.0],
"0.52": [1408.0, 2688.0],
"0.57": [1536.0, 2688.0],
"0.6": [1536.0, 2560.0],
"0.68": [1664.0, 2432.0],
"0.72": [1664.0, 2304.0],
"0.78": [1792.0, 2304.0],
"0.82": [1792.0, 2176.0],
"0.88": [1920.0, 2176.0],
"0.94": [1920.0, 2048.0],
"1.0": [2048.0, 2048.0],
"1.07": [2048.0, 1920.0],
"1.13": [2176.0, 1920.0],
"1.21": [2176.0, 1792.0],
"1.29": [2304.0, 1792.0],
"1.38": [2304.0, 1664.0],
"1.46": [2432.0, 1664.0],
"1.67": [2560.0, 1536.0],
"1.75": [2688.0, 1536.0],
"2.0": [2816.0, 1408.0],
"2.09": [2944.0, 1408.0],
"2.4": [3072.0, 1280.0],
"2.5": [3200.0, 1280.0],
"2.89": [3328.0, 1152.0],
"3.0": [3456.0, 1152.0],
"3.11": [3584.0, 1152.0],
"3.62": [3712.0, 1024.0],
"3.75": [3840.0, 1024.0],
"3.88": [3968.0, 1024.0],
"4.0": [4096.0, 1024.0]
}
ASPECT_RATIO_256_BIN = {
"0.25": [128.0, 512.0],
"0.28": [128.0, 464.0],
"0.32": [144.0, 448.0],
"0.33": [144.0, 432.0],
"0.35": [144.0, 416.0],
"0.4": [160.0, 400.0],
"0.42": [160.0, 384.0],
"0.48": [176.0, 368.0],
"0.5": [176.0, 352.0],
"0.52": [176.0, 336.0],
"0.57": [192.0, 336.0],
"0.6": [192.0, 320.0],
"0.68": [208.0, 304.0],
"0.72": [208.0, 288.0],
"0.78": [224.0, 288.0],
"0.82": [224.0, 272.0],
"0.88": [240.0, 272.0],
"0.94": [240.0, 256.0],
"1.0": [256.0, 256.0],
"1.07": [256.0, 240.0],
"1.13": [272.0, 240.0],
"1.21": [272.0, 224.0],
"1.29": [288.0, 224.0],
"1.38": [288.0, 208.0],
"1.46": [304.0, 208.0],
"1.67": [320.0, 192.0],
"1.75": [336.0, 192.0],
"2.0": [352.0, 176.0],
"2.09": [368.0, 176.0],
"2.4": [384.0, 160.0],
"2.5": [400.0, 160.0],
"3.0": [432.0, 144.0],
"4.0": [512.0, 128.0]
}
ASPECT_RATIO_1024_BIN = {
"0.25": [512.0, 2048.0],
"0.28": [512.0, 1856.0],
"0.32": [576.0, 1792.0],
"0.33": [576.0, 1728.0],
"0.35": [576.0, 1664.0],
"0.4": [640.0, 1600.0],
"0.42": [640.0, 1536.0],
"0.48": [704.0, 1472.0],
"0.5": [704.0, 1408.0],
"0.52": [704.0, 1344.0],
"0.57": [768.0, 1344.0],
"0.6": [768.0, 1280.0],
"0.68": [832.0, 1216.0],
"0.72": [832.0, 1152.0],
"0.78": [896.0, 1152.0],
"0.82": [896.0, 1088.0],
"0.88": [960.0, 1088.0],
"0.94": [960.0, 1024.0],
"1.0": [1024.0, 1024.0],
"1.07": [1024.0, 960.0],
"1.13": [1088.0, 960.0],
"1.21": [1088.0, 896.0],
"1.29": [1152.0, 896.0],
"1.38": [1152.0, 832.0],
"1.46": [1216.0, 832.0],
"1.67": [1280.0, 768.0],
"1.75": [1344.0, 768.0],
"2.0": [1408.0, 704.0],
"2.09": [1472.0, 704.0],
"2.4": [1536.0, 640.0],
"2.5": [1600.0, 640.0],
"3.0": [1728.0, 576.0],
"4.0": [2048.0, 512.0],
}
ASPECT_RATIO_512_BIN = {
"0.25": [256.0, 1024.0],
"0.28": [256.0, 928.0],
"0.32": [288.0, 896.0],
"0.33": [288.0, 864.0],
"0.35": [288.0, 832.0],
"0.4": [320.0, 800.0],
"0.42": [320.0, 768.0],
"0.48": [352.0, 736.0],
"0.5": [352.0, 704.0],
"0.52": [352.0, 672.0],
"0.57": [384.0, 672.0],
"0.6": [384.0, 640.0],
"0.68": [416.0, 608.0],
"0.72": [416.0, 576.0],
"0.78": [448.0, 576.0],
"0.82": [448.0, 544.0],
"0.88": [480.0, 544.0],
"0.94": [480.0, 512.0],
"1.0": [512.0, 512.0],
"1.07": [512.0, 480.0],
"1.13": [544.0, 480.0],
"1.21": [544.0, 448.0],
"1.29": [576.0, 448.0],
"1.38": [576.0, 416.0],
"1.46": [608.0, 416.0],
"1.67": [640.0, 384.0],
"1.75": [672.0, 384.0],
"2.0": [704.0, 352.0],
"2.09": [736.0, 352.0],
"2.4": [768.0, 320.0],
"2.5": [800.0, 320.0],
"3.0": [864.0, 288.0],
"4.0": [1024.0, 256.0],
}
def pipeline_pixart_alpha_call(
self,
prompt: Union[str, List[str]] = None,
negative_prompt: str = "",
num_inference_steps: int = 20,
timesteps: List[int] = None,
guidance_scale: float = 4.5,
num_images_per_prompt: Optional[int] = 1,
height: Optional[int] = None,
width: Optional[int] = None,
eta: float = 0.0,
generator: Optional[Union[torch.Generator, List[torch.Generator]]] = None,
latents: Optional[torch.FloatTensor] = None,
prompt_embeds: Optional[torch.FloatTensor] = None,
prompt_attention_mask: Optional[torch.FloatTensor] = None,
negative_prompt_embeds: Optional[torch.FloatTensor] = None,
negative_prompt_attention_mask: Optional[torch.FloatTensor] = None,
output_type: Optional[str] = "pil",
return_dict: bool = True,
callback: Optional[Callable[[int, int, torch.FloatTensor], None]] = None,
callback_steps: int = 1,
clean_caption: bool = True,
use_resolution_binning: bool = True,
max_sequence_length: int = 120,
**kwargs,
) -> Union[ImagePipelineOutput, Tuple]:
"""
Function invoked when calling the pipeline for generation.
Args:
prompt (`str` or `List[str]`, *optional*):
The prompt or prompts to guide the image generation. If not defined, one has to pass `prompt_embeds`.
instead.
negative_prompt (`str` or `List[str]`, *optional*):
The prompt or prompts not to guide the image generation. If not defined, one has to pass
`negative_prompt_embeds` instead. Ignored when not using guidance (i.e., ignored if `guidance_scale` is
less than `1`).
num_inference_steps (`int`, *optional*, defaults to 100):
The number of denoising steps. More denoising steps usually lead to a higher quality image at the
expense of slower inference.
timesteps (`List[int]`, *optional*):
Custom timesteps to use for the denoising process. If not defined, equal spaced `num_inference_steps`
timesteps are used. Must be in descending order.
guidance_scale (`float`, *optional*, defaults to 4.5):
Guidance scale as defined in [Classifier-Free Diffusion Guidance](https://arxiv.org/abs/2207.12598).
`guidance_scale` is defined as `w` of equation 2. of [Imagen
Paper](https://arxiv.org/pdf/2205.11487.pdf). Guidance scale is enabled by setting `guidance_scale >
1`. Higher guidance scale encourages to generate images that are closely linked to the text `prompt`,
usually at the expense of lower image quality.
num_images_per_prompt (`int`, *optional*, defaults to 1):
The number of images to generate per prompt.
height (`int`, *optional*, defaults to self.unet.config.sample_size):
The height in pixels of the generated image.
width (`int`, *optional*, defaults to self.unet.config.sample_size):
The width in pixels of the generated image.
eta (`float`, *optional*, defaults to 0.0):
Corresponds to parameter eta (η) in the DDIM paper: https://arxiv.org/abs/2010.02502. Only applies to
[`schedulers.DDIMScheduler`], will be ignored for others.
generator (`torch.Generator` or `List[torch.Generator]`, *optional*):
One or a list of [torch generator(s)](https://pytorch.org/docs/stable/generated/torch.Generator.html)
to make generation deterministic.
latents (`torch.FloatTensor`, *optional*):
Pre-generated noisy latents, sampled from a Gaussian distribution, to be used as inputs for image
generation. Can be used to tweak the same generation with different prompts. If not provided, a latents
tensor will ge generated by sampling using the supplied random `generator`.
prompt_embeds (`torch.FloatTensor`, *optional*):
Pre-generated text embeddings. Can be used to easily tweak text inputs, *e.g.* prompt weighting. If not
provided, text embeddings will be generated from `prompt` input argument.
prompt_attention_mask (`torch.FloatTensor`, *optional*): Pre-generated attention mask for text embeddings.
negative_prompt_embeds (`torch.FloatTensor`, *optional*):
Pre-generated negative text embeddings. For PixArt-Alpha this negative prompt should be "". If not
provided, negative_prompt_embeds will be generated from `negative_prompt` input argument.
negative_prompt_attention_mask (`torch.FloatTensor`, *optional*):
Pre-generated attention mask for negative text embeddings.
output_type (`str`, *optional*, defaults to `"pil"`):
The output format of the generate image. Choose between
[PIL](https://pillow.readthedocs.io/en/stable/): `PIL.Image.Image` or `np.array`.
return_dict (`bool`, *optional*, defaults to `True`):
Whether or not to return a [`~pipelines.stable_diffusion.IFPipelineOutput`] instead of a plain tuple.
callback (`Callable`, *optional*):
A function that will be called every `callback_steps` steps during inference. The function will be
called with the following arguments: `callback(step: int, timestep: int, latents: torch.FloatTensor)`.
callback_steps (`int`, *optional*, defaults to 1):
The frequency at which the `callback` function will be called. If not specified, the callback will be
called at every step.
clean_caption (`bool`, *optional*, defaults to `True`):
Whether or not to clean the caption before creating embeddings. Requires `beautifulsoup4` and `ftfy` to
be installed. If the dependencies are not installed, the embeddings will be created from the raw
prompt.
use_resolution_binning (`bool` defaults to `True`):
If set to `True`, the requested height and width are first mapped to the closest resolutions using
`ASPECT_RATIO_1024_BIN`. After the produced latents are decoded into images, they are resized back to
the requested resolution. Useful for generating non-square images.
Examples:
Returns:
[`~pipelines.ImagePipelineOutput`] or `tuple`:
If `return_dict` is `True`, [`~pipelines.ImagePipelineOutput`] is returned, otherwise a `tuple` is
returned where the first element is a list with the generated images
"""
if "mask_feature" in kwargs:
deprecation_message = "The use of `mask_feature` is deprecated. It is no longer used in any computation and that doesn't affect the end results. It will be removed in a future version."
deprecate("mask_feature", "1.0.0", deprecation_message, standard_warn=False)
# 1. Check inputs. Raise error if not correct
height = height or self.transformer.config.sample_size * self.vae_scale_factor
width = width or self.transformer.config.sample_size * self.vae_scale_factor
if use_resolution_binning:
if self.transformer.config.sample_size == 32:
aspect_ratio_bin = ASPECT_RATIO_256_BIN
elif self.transformer.config.sample_size == 64:
aspect_ratio_bin = ASPECT_RATIO_512_BIN
elif self.transformer.config.sample_size == 128:
aspect_ratio_bin = ASPECT_RATIO_1024_BIN
elif self.transformer.config.sample_size == 256:
aspect_ratio_bin = ASPECT_RATIO_2048_BIN
else:
raise ValueError("Invalid sample size")
orig_height, orig_width = height, width
height, width = self.classify_height_width_bin(height, width, ratios=aspect_ratio_bin)
self.check_inputs(
prompt,
height,
width,
negative_prompt,
callback_steps,
prompt_embeds,
negative_prompt_embeds,
prompt_attention_mask,
negative_prompt_attention_mask,
)
# 2. Default height and width to transformer
if prompt is not None and isinstance(prompt, str):
batch_size = 1
elif prompt is not None and isinstance(prompt, list):
batch_size = len(prompt)
else:
batch_size = prompt_embeds.shape[0]
device = self._execution_device
# here `guidance_scale` is defined analog to the guidance weight `w` of equation (2)
# of the Imagen paper: https://arxiv.org/pdf/2205.11487.pdf . `guidance_scale = 1`
# corresponds to doing no classifier free guidance.
do_classifier_free_guidance = guidance_scale > 1.0
# 3. Encode input prompt
(
prompt_embeds,
prompt_attention_mask,
negative_prompt_embeds,
negative_prompt_attention_mask,
) = self.encode_prompt(
prompt,
do_classifier_free_guidance,
negative_prompt=negative_prompt,
num_images_per_prompt=num_images_per_prompt,
device=device,
prompt_embeds=prompt_embeds,
negative_prompt_embeds=negative_prompt_embeds,
prompt_attention_mask=prompt_attention_mask,
negative_prompt_attention_mask=negative_prompt_attention_mask,
clean_caption=clean_caption,
max_sequence_length=max_sequence_length,
)
if do_classifier_free_guidance:
prompt_embeds = torch.cat([negative_prompt_embeds, prompt_embeds], dim=0)
prompt_attention_mask = torch.cat([negative_prompt_attention_mask, prompt_attention_mask], dim=0)
# 4. Prepare timesteps
timesteps, num_inference_steps = retrieve_timesteps(self.scheduler, num_inference_steps, device, timesteps)
# 5. Prepare latents.
latent_channels = self.transformer.config.in_channels
latents = self.prepare_latents(
batch_size * num_images_per_prompt,
latent_channels,
height,
width,
prompt_embeds.dtype,
device,
generator,
latents,
)
# 6. Prepare extra step kwargs. TODO: Logic should ideally just be moved out of the pipeline
extra_step_kwargs = self.prepare_extra_step_kwargs(generator, eta)
# 6.1 Prepare micro-conditions.
added_cond_kwargs = {"resolution": None, "aspect_ratio": None}
if self.transformer.config.sample_size == 128:
resolution = torch.tensor([height, width]).repeat(batch_size * num_images_per_prompt, 1)
aspect_ratio = torch.tensor([float(height / width)]).repeat(batch_size * num_images_per_prompt, 1)
resolution = resolution.to(dtype=prompt_embeds.dtype, device=device)
aspect_ratio = aspect_ratio.to(dtype=prompt_embeds.dtype, device=device)
if do_classifier_free_guidance:
resolution = torch.cat([resolution, resolution], dim=0)
aspect_ratio = torch.cat([aspect_ratio, aspect_ratio], dim=0)
added_cond_kwargs = {"resolution": resolution, "aspect_ratio": aspect_ratio}
# 7. Denoising loop
num_warmup_steps = max(len(timesteps) - num_inference_steps * self.scheduler.order, 0)
with self.progress_bar(total=num_inference_steps) as progress_bar:
for i, t in enumerate(timesteps):
latent_model_input = torch.cat([latents] * 2) if do_classifier_free_guidance else latents
latent_model_input = self.scheduler.scale_model_input(latent_model_input, t)
current_timestep = t
if not torch.is_tensor(current_timestep):
# TODO: this requires sync between CPU and GPU. So try to pass timesteps as tensors if you can
# This would be a good case for the `match` statement (Python 3.10+)
is_mps = latent_model_input.device.type == "mps"
if isinstance(current_timestep, float):
dtype = torch.float32 if is_mps else torch.float64
else:
dtype = torch.int32 if is_mps else torch.int64
current_timestep = torch.tensor([current_timestep], dtype=dtype, device=latent_model_input.device)
elif len(current_timestep.shape) == 0:
current_timestep = current_timestep[None].to(latent_model_input.device)
# broadcast to batch dimension in a way that's compatible with ONNX/Core ML
current_timestep = current_timestep.expand(latent_model_input.shape[0])
# predict noise model_output
noise_pred = self.transformer(
latent_model_input,
encoder_hidden_states=prompt_embeds,
encoder_attention_mask=prompt_attention_mask,
timestep=current_timestep,
added_cond_kwargs=added_cond_kwargs,
return_dict=False,
)[0]
# perform guidance
if do_classifier_free_guidance:
noise_pred_uncond, noise_pred_text = noise_pred.chunk(2)
noise_pred = noise_pred_uncond + guidance_scale * (noise_pred_text - noise_pred_uncond)
# learned sigma
if self.transformer.config.out_channels // 2 == latent_channels:
noise_pred = noise_pred.chunk(2, dim=1)[0]
else:
noise_pred = noise_pred
# compute previous image: x_t -> x_t-1
if num_inference_steps == 1:
latents = self.scheduler.step(noise_pred, t, latents, **extra_step_kwargs).pred_original_sample
else:
latents = self.scheduler.step(noise_pred, t, latents, **extra_step_kwargs, return_dict=False)[0]
# call the callback, if provided
if i == len(timesteps) - 1 or ((i + 1) > num_warmup_steps and (i + 1) % self.scheduler.order == 0):
progress_bar.update()
if callback is not None and i % callback_steps == 0:
step_idx = i // getattr(self.scheduler, "order", 1)
callback(step_idx, t, latents)
if not output_type == "latent":
image = self.vae.decode(latents / self.vae.config.scaling_factor, return_dict=False)[0]
if use_resolution_binning:
image = self.resize_and_crop_tensor(image, orig_width, orig_height)
else:
image = latents
if not output_type == "latent":
image = self.image_processor.postprocess(image, output_type=output_type)
# Offload all models
self.maybe_free_model_hooks()
if not return_dict:
return (image,)
return ImagePipelineOutput(images=image)
class PixArtSigmaPipeline(PixArtAlphaPipeline):
r"""
tmp Pipeline for text-to-image generation using PixArt-Sigma.
"""
def __init__(
self,
tokenizer: T5Tokenizer,
text_encoder: T5EncoderModel,
vae: AutoencoderKL,
transformer: Transformer2DModel,
scheduler: DPMSolverMultistepScheduler,
):
super().__init__(tokenizer, text_encoder, vae, transformer, scheduler)
self.register_modules(
tokenizer=tokenizer, text_encoder=text_encoder, vae=vae, transformer=transformer, scheduler=scheduler
)
self.vae_scale_factor = 2 ** (len(self.vae.config.block_out_channels) - 1)
self.image_processor = VaeImageProcessor(vae_scale_factor=self.vae_scale_factor)
def pixart_sigma_init_patched_inputs(self, norm_type):
assert self.config.sample_size is not None, "Transformer2DModel over patched input must provide sample_size"
self.height = self.config.sample_size
self.width = self.config.sample_size
self.patch_size = self.config.patch_size
interpolation_scale = (
self.config.interpolation_scale
if self.config.interpolation_scale is not None
else max(self.config.sample_size // 64, 1)
)
self.pos_embed = PatchEmbed(
height=self.config.sample_size,
width=self.config.sample_size,
patch_size=self.config.patch_size,
in_channels=self.in_channels,
embed_dim=self.inner_dim,
interpolation_scale=interpolation_scale,
)
self.transformer_blocks = nn.ModuleList(
[
BasicTransformerBlock(
self.inner_dim,
self.config.num_attention_heads,
self.config.attention_head_dim,
dropout=self.config.dropout,
cross_attention_dim=self.config.cross_attention_dim,
activation_fn=self.config.activation_fn,
num_embeds_ada_norm=self.config.num_embeds_ada_norm,
attention_bias=self.config.attention_bias,
only_cross_attention=self.config.only_cross_attention,
double_self_attention=self.config.double_self_attention,
upcast_attention=self.config.upcast_attention,
norm_type=norm_type,
norm_elementwise_affine=self.config.norm_elementwise_affine,
norm_eps=self.config.norm_eps,
attention_type=self.config.attention_type,
)
for _ in range(self.config.num_layers)
]
)
if self.config.norm_type != "ada_norm_single":
self.norm_out = nn.LayerNorm(self.inner_dim, elementwise_affine=False, eps=1e-6)
self.proj_out_1 = nn.Linear(self.inner_dim, 2 * self.inner_dim)
self.proj_out_2 = nn.Linear(
self.inner_dim, self.config.patch_size * self.config.patch_size * self.out_channels
)
elif self.config.norm_type == "ada_norm_single":
self.norm_out = nn.LayerNorm(self.inner_dim, elementwise_affine=False, eps=1e-6)
self.scale_shift_table = nn.Parameter(torch.randn(2, self.inner_dim) / self.inner_dim ** 0.5)
self.proj_out = nn.Linear(
self.inner_dim, self.config.patch_size * self.config.patch_size * self.out_channels
)
# PixArt-Sigma blocks.
self.adaln_single = None
self.use_additional_conditions = False
if self.config.norm_type == "ada_norm_single":
# TODO(Sayak, PVP) clean this, PixArt-Sigma doesn't use additional_conditions anymore
# additional conditions until we find better name
self.adaln_single = AdaLayerNormSingle(
self.inner_dim, use_additional_conditions=self.use_additional_conditions
)
self.caption_projection = None
if self.caption_channels is not None:
self.caption_projection = PixArtAlphaTextProjection(
in_features=self.caption_channels, hidden_size=self.inner_dim
)