Spaces:
Running
on
A10G
Running
on
A10G
| import os | |
| import torch | |
| import collections | |
| import torch.nn as nn | |
| from functools import partial | |
| from transformers import CLIPTextModel, CLIPTokenizer, logging | |
| from diffusers import AutoencoderKL, PNDMScheduler, EulerDiscreteScheduler, DPMSolverMultistepScheduler | |
| from models.unet_2d_condition import UNet2DConditionModel | |
| # suppress partial model loading warning | |
| logging.set_verbosity_error() | |
| class RegionDiffusion(nn.Module): | |
| def __init__(self, device): | |
| super().__init__() | |
| self.device = device | |
| self.num_train_timesteps = 1000 | |
| self.clip_gradient = False | |
| print(f'[INFO] loading stable diffusion...') | |
| model_id = 'runwayml/stable-diffusion-v1-5' | |
| self.vae = AutoencoderKL.from_pretrained( | |
| model_id, subfolder="vae").to(self.device) | |
| self.tokenizer = CLIPTokenizer.from_pretrained( | |
| model_id, subfolder='tokenizer') | |
| self.text_encoder = CLIPTextModel.from_pretrained( | |
| model_id, subfolder='text_encoder').to(self.device) | |
| self.unet = UNet2DConditionModel.from_pretrained( | |
| model_id, subfolder="unet").to(self.device) | |
| self.scheduler = PNDMScheduler(beta_start=0.00085, beta_end=0.012, beta_schedule="scaled_linear", | |
| num_train_timesteps=self.num_train_timesteps, skip_prk_steps=True, steps_offset=1) | |
| self.alphas_cumprod = self.scheduler.alphas_cumprod.to(self.device) | |
| self.masks = [] | |
| self.attention_maps = None | |
| self.color_loss = torch.nn.functional.mse_loss | |
| print(f'[INFO] loaded stable diffusion!') | |
| def get_text_embeds(self, prompt, negative_prompt): | |
| # prompt, negative_prompt: [str] | |
| # Tokenize text and get embeddings | |
| text_input = self.tokenizer( | |
| prompt, padding='max_length', max_length=self.tokenizer.model_max_length, truncation=True, return_tensors='pt') | |
| with torch.no_grad(): | |
| text_embeddings = self.text_encoder( | |
| text_input.input_ids.to(self.device))[0] | |
| # Do the same for unconditional embeddings | |
| uncond_input = self.tokenizer(negative_prompt, padding='max_length', | |
| max_length=self.tokenizer.model_max_length, return_tensors='pt') | |
| with torch.no_grad(): | |
| uncond_embeddings = self.text_encoder( | |
| uncond_input.input_ids.to(self.device))[0] | |
| # Cat for final embeddings | |
| text_embeddings = torch.cat([uncond_embeddings, text_embeddings]) | |
| return text_embeddings | |
| def get_text_embeds_list(self, prompts): | |
| # prompts: [list] | |
| text_embeddings = [] | |
| for prompt in prompts: | |
| # Tokenize text and get embeddings | |
| text_input = self.tokenizer( | |
| [prompt], padding='max_length', max_length=self.tokenizer.model_max_length, truncation=True, return_tensors='pt') | |
| with torch.no_grad(): | |
| text_embeddings.append(self.text_encoder( | |
| text_input.input_ids.to(self.device))[0]) | |
| return text_embeddings | |
| def produce_latents(self, text_embeddings, height=512, width=512, num_inference_steps=50, guidance_scale=7.5, | |
| latents=None, use_grad_guidance=False, text_format_dict={}): | |
| if latents is None: | |
| latents = torch.randn( | |
| (1, self.unet.in_channels, height // 8, width // 8), device=self.device) | |
| self.scheduler.set_timesteps(num_inference_steps) | |
| n_styles = text_embeddings.shape[0]-1 | |
| assert n_styles == len(self.masks) | |
| with torch.autocast('cuda'): | |
| for i, t in enumerate(self.scheduler.timesteps): | |
| # predict the noise residual | |
| with torch.no_grad(): | |
| noise_pred_uncond = self.unet(latents, t, encoder_hidden_states=text_embeddings[:1], | |
| text_format_dict={})['sample'] | |
| noise_pred_text = None | |
| for style_i, mask in enumerate(self.masks): | |
| if style_i < len(self.masks) - 1: | |
| masked_latent = latents | |
| noise_pred_text_cur = self.unet(masked_latent, t, encoder_hidden_states=text_embeddings[style_i+1:style_i+2], | |
| text_format_dict={})['sample'] | |
| else: | |
| noise_pred_text_cur = self.unet(latents, t, encoder_hidden_states=text_embeddings[style_i+1:style_i+2], | |
| text_format_dict=text_format_dict)['sample'] | |
| if noise_pred_text is None: | |
| noise_pred_text = noise_pred_text_cur * mask | |
| else: | |
| noise_pred_text = noise_pred_text + noise_pred_text_cur*mask | |
| # perform classifier-free guidance | |
| noise_pred = noise_pred_uncond + guidance_scale * \ | |
| (noise_pred_text - noise_pred_uncond) | |
| # compute the previous noisy sample x_t -> x_t-1 | |
| latents = self.scheduler.step(noise_pred, t, latents)[ | |
| 'prev_sample'] | |
| # apply gradient guidance | |
| if use_grad_guidance and t < text_format_dict['guidance_start_step']: | |
| with torch.enable_grad(): | |
| if not latents.requires_grad: | |
| latents.requires_grad = True | |
| latents_0 = self.predict_x0(latents, noise_pred, t) | |
| latents_inp = 1 / 0.18215 * latents_0 | |
| imgs = self.vae.decode(latents_inp).sample | |
| imgs = (imgs / 2 + 0.5).clamp(0, 1) | |
| loss_total = 0. | |
| for attn_map, rgb_val in zip(text_format_dict['color_obj_atten'], text_format_dict['target_RGB']): | |
| avg_rgb = ( | |
| imgs*attn_map[:, 0]).sum(2).sum(2)/attn_map[:, 0].sum() | |
| loss = self.color_loss( | |
| avg_rgb, rgb_val[:, :, 0, 0])*100 | |
| # print(loss) | |
| loss_total += loss | |
| loss_total.backward() | |
| latents = ( | |
| latents - latents.grad * text_format_dict['color_guidance_weight']).detach().clone() | |
| return latents | |
| def predict_x0(self, x_t, eps_t, t): | |
| alpha_t = self.scheduler.alphas_cumprod[t] | |
| return (x_t - eps_t * torch.sqrt(1-alpha_t)) / torch.sqrt(alpha_t) | |
| def produce_attn_maps(self, prompts, negative_prompts='', height=512, width=512, num_inference_steps=50, | |
| guidance_scale=7.5, latents=None): | |
| if isinstance(prompts, str): | |
| prompts = [prompts] | |
| if isinstance(negative_prompts, str): | |
| negative_prompts = [negative_prompts] | |
| # Prompts -> text embeds | |
| text_embeddings = self.get_text_embeds( | |
| prompts, negative_prompts) # [2, 77, 768] | |
| if latents is None: | |
| latents = torch.randn( | |
| (text_embeddings.shape[0] // 2, self.unet.in_channels, height // 8, width // 8), device=self.device) | |
| self.scheduler.set_timesteps(num_inference_steps) | |
| with torch.autocast('cuda'): | |
| for i, t in enumerate(self.scheduler.timesteps): | |
| # expand the latents if we are doing classifier-free guidance to avoid doing two forward passes. | |
| latent_model_input = torch.cat([latents] * 2) | |
| # predict the noise residual | |
| with torch.no_grad(): | |
| noise_pred = self.unet( | |
| latent_model_input, t, encoder_hidden_states=text_embeddings)['sample'] | |
| # perform guidance | |
| noise_pred_uncond, noise_pred_text = noise_pred.chunk(2) | |
| noise_pred = noise_pred_uncond + guidance_scale * \ | |
| (noise_pred_text - noise_pred_uncond) | |
| # compute the previous noisy sample x_t -> x_t-1 | |
| latents = self.scheduler.step(noise_pred, t, latents)[ | |
| 'prev_sample'] | |
| # Img latents -> imgs | |
| imgs = self.decode_latents(latents) # [1, 3, 512, 512] | |
| # Img to Numpy | |
| imgs = imgs.detach().cpu().permute(0, 2, 3, 1).numpy() | |
| imgs = (imgs * 255).round().astype('uint8') | |
| return imgs | |
| def decode_latents(self, latents): | |
| latents = 1 / 0.18215 * latents | |
| with torch.no_grad(): | |
| imgs = self.vae.decode(latents).sample | |
| imgs = (imgs / 2 + 0.5).clamp(0, 1) | |
| return imgs | |
| def prompt_to_img(self, prompts, negative_prompts='', height=512, width=512, num_inference_steps=50, | |
| guidance_scale=7.5, latents=None, text_format_dict={}, use_grad_guidance=False): | |
| if isinstance(prompts, str): | |
| prompts = [prompts] | |
| if isinstance(negative_prompts, str): | |
| negative_prompts = [negative_prompts] | |
| # Prompts -> text embeds | |
| text_embeds = self.get_text_embeds( | |
| prompts, negative_prompts) # [2, 77, 768] | |
| if len(text_format_dict) > 0: | |
| if 'font_styles' in text_format_dict and text_format_dict['font_styles'] is not None: | |
| text_format_dict['font_styles_embs'] = self.get_text_embeds_list( | |
| text_format_dict['font_styles']) # [2, 77, 768] | |
| else: | |
| text_format_dict['font_styles_embs'] = None | |
| # else: | |
| latents = self.produce_latents(text_embeds, height=height, width=width, latents=latents, | |
| num_inference_steps=num_inference_steps, guidance_scale=guidance_scale, | |
| use_grad_guidance=use_grad_guidance, text_format_dict=text_format_dict) # [1, 4, 64, 64] | |
| # Img latents -> imgs | |
| imgs = self.decode_latents(latents) # [1, 3, 512, 512] | |
| # Img to Numpy | |
| imgs = imgs.detach().cpu().permute(0, 2, 3, 1).numpy() | |
| imgs = (imgs * 255).round().astype('uint8') | |
| return imgs | |
| def reset_attention_maps(self): | |
| r"""Function to reset attention maps. | |
| We reset attention maps because we append them while getting hooks | |
| to visualize attention maps for every step. | |
| """ | |
| for key in self.attention_maps: | |
| self.attention_maps[key] = [] | |
| def register_evaluation_hooks(self): | |
| r"""Function for registering hooks during evaluation. | |
| We mainly store activation maps averaged over queries. | |
| """ | |
| self.forward_hooks = [] | |
| def save_activations(activations, name, module, inp, out): | |
| r""" | |
| PyTorch Forward hook to save outputs at each forward pass. | |
| """ | |
| # out[0] - final output of attention layer | |
| # out[1] - attention probability matrix | |
| if 'attn2' in name: | |
| assert out[1].shape[-1] == 77 | |
| activations[name].append(out[1].detach().cpu()) | |
| else: | |
| assert out[1].shape[-1] != 77 | |
| attention_dict = collections.defaultdict(list) | |
| for name, module in self.unet.named_modules(): | |
| leaf_name = name.split('.')[-1] | |
| if 'attn' in leaf_name: | |
| # Register hook to obtain outputs at every attention layer. | |
| self.forward_hooks.append(module.register_forward_hook( | |
| partial(save_activations, attention_dict, name) | |
| )) | |
| # attention_dict is a dictionary containing attention maps for every attention layer | |
| self.attention_maps = attention_dict | |
| def remove_evaluation_hooks(self): | |
| for hook in self.forward_hooks: | |
| hook.remove() | |
| self.attention_maps = None | |