File size: 8,688 Bytes
913d3e3
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
import torch.nn as nn
import torchvision
from scipy.spatial import Delaunay
import torch
import numpy as np
from torch.nn import functional as nnf
from easydict import EasyDict
from shapely.geometry import Point
from shapely.geometry.polygon import Polygon
from torchvision import transforms
from PIL import Image
from transformers import CLIPProcessor, CLIPModel

from diffusers import StableDiffusionPipeline

class SDSLoss(nn.Module):
    def __init__(self, cfg, device):
        super(SDSLoss, self).__init__()
        self.cfg = cfg
        self.device = device
        self.pipe = StableDiffusionPipeline.from_pretrained(cfg.diffusion.model,
                                                       torch_dtype=torch.float16, use_auth_token=cfg.token)
        self.pipe = self.pipe.to(self.device)

        self.clip_model = CLIPModel.from_pretrained("openai/clip-vit-large-patch14").to(self.device)
        self.clip_processor = CLIPProcessor.from_pretrained("openai/clip-vit-large-patch14")
    
        # default scheduler: PNDMScheduler(beta_start=0.00085, beta_end=0.012,
        # beta_schedule="scaled_linear", num_train_timesteps=1000)
        self.alphas = self.pipe.scheduler.alphas_cumprod.to(self.device)
        self.sigmas = (1 - self.pipe.scheduler.alphas_cumprod).to(self.device)

        self.text_embeddings = None
        self.embed_text()

    def embed_text(self):
        # tokenizer and embed text

        if "jpeg" not in self.cfg.caption:
          text_input = self.pipe.tokenizer(self.cfg.caption, padding="max_length",
                                          max_length=self.pipe.tokenizer.model_max_length,
                                          truncation=True, return_tensors="pt")
          uncond_input = self.pipe.tokenizer([""], padding="max_length",
                                          max_length=text_input.input_ids.shape[-1],
                                          return_tensors="pt")
          with torch.no_grad():
              text_embeddings = self.pipe.text_encoder(text_input.input_ids.to(self.device))[0]
              uncond_embeddings = self.pipe.text_encoder(uncond_input.input_ids.to(self.device))[0]
        else:
            print(f"> Reading Image {self.cfg.caption}")
            with torch.no_grad():
                image = Image.open(self.cfg.caption)
                inputs = self.clip_processor(images=image, return_tensors="pt").to(self.device)
                img_emb = self.clip_model.get_image_features(**inputs)
            text_embeddings = img_emb
            uncond_embeddings = img_emb

        print(text_embeddings.size())
        print(uncond_embeddings.size())
        self.text_embeddings = torch.cat([uncond_embeddings, text_embeddings])
        self.text_embeddings = self.text_embeddings.repeat_interleave(self.cfg.batch_size, 0)
        del self.pipe.tokenizer
        del self.pipe.text_encoder


    def forward(self, x_aug):
        sds_loss = 0

        # encode rendered image
        x = x_aug * 2. - 1.
        with torch.cuda.amp.autocast():
            init_latent_z = (self.pipe.vae.encode(x).latent_dist.sample())
        latent_z = 0.18215 * init_latent_z  # scaling_factor * init_latents

        with torch.inference_mode():
            # sample timesteps
            timestep = torch.randint(
                low=50,
                high=min(950, self.cfg.diffusion.timesteps) - 1,  # avoid highest timestep | diffusion.timesteps=1000
                size=(latent_z.shape[0],),
                device=self.device, dtype=torch.long)

            # add noise
            eps = torch.randn_like(latent_z)
            # zt = alpha_t * latent_z + sigma_t * eps
            noised_latent_zt = self.pipe.scheduler.add_noise(latent_z, eps, timestep)

            # denoise
            z_in = torch.cat([noised_latent_zt] * 2)  # expand latents for classifier free guidance
            timestep_in = torch.cat([timestep] * 2)
            with torch.autocast(device_type="cuda", dtype=torch.float16):
                eps_t_uncond, eps_t = self.pipe.unet(z_in, timestep, encoder_hidden_states=self.text_embeddings).sample.float().chunk(2)

            eps_t = eps_t_uncond + self.cfg.diffusion.guidance_scale * (eps_t - eps_t_uncond)

            # w = alphas[timestep]^0.5 * (1 - alphas[timestep]) = alphas[timestep]^0.5 * sigmas[timestep]
            grad_z = self.alphas[timestep]**0.5 * self.sigmas[timestep] * (eps_t - eps)
            assert torch.isfinite(grad_z).all()
            grad_z = torch.nan_to_num(grad_z.detach().float(), 0.0, 0.0, 0.0)

        sds_loss = grad_z.clone() * latent_z
        del grad_z

        sds_loss = sds_loss.sum(1).mean()
        return sds_loss


class ToneLoss(nn.Module):
    def __init__(self, cfg):
        super(ToneLoss, self).__init__()
        self.dist_loss_weight = cfg.loss.tone.dist_loss_weight
        self.im_init = None
        self.cfg = cfg
        self.mse_loss = nn.MSELoss()
        self.blurrer = torchvision.transforms.GaussianBlur(kernel_size=(cfg.loss.tone.pixel_dist_kernel_blur,
                                                                        cfg.loss.tone.pixel_dist_kernel_blur), sigma=(cfg.loss.tone.pixel_dist_sigma))

    def set_image_init(self, im_init):
        self.im_init = im_init.permute(2, 0, 1).unsqueeze(0)
        self.init_blurred = self.blurrer(self.im_init)


    def get_scheduler(self, step=None):
        if step is not None:
            return self.dist_loss_weight * np.exp(-(1/5)*((step-300)/(20)) ** 2)
        else:
            return self.dist_loss_weight

    def forward(self, cur_raster, step=None):
        blurred_cur = self.blurrer(cur_raster)
        return self.mse_loss(self.init_blurred.detach(), blurred_cur) * self.get_scheduler(step)
            

class ConformalLoss:
    def __init__(self, parameters: EasyDict, device: torch.device, target_letter: str, shape_groups):
        self.parameters = parameters
        self.target_letter = target_letter
        self.shape_groups = shape_groups
        self.faces = self.init_faces(device)
        self.faces_roll_a = [torch.roll(self.faces[i], 1, 1) for i in range(len(self.faces))]

        with torch.no_grad():
            self.angles = []
            self.reset()


    def get_angles(self, points: torch.Tensor) -> torch.Tensor:
        angles_ = []
        for i in range(len(self.faces)):
            triangles = points[self.faces[i]]
            triangles_roll_a = points[self.faces_roll_a[i]]
            edges = triangles_roll_a - triangles
            length = edges.norm(dim=-1)
            edges = edges / (length + 1e-1)[:, :, None]
            edges_roll = torch.roll(edges, 1, 1)
            cosine = torch.einsum('ned,ned->ne', edges, edges_roll)
            angles = torch.arccos(cosine)
            angles_.append(angles)
        return angles_
    
    def get_letter_inds(self, letter_to_insert):
        for group, l in zip(self.shape_groups, self.target_letter):
            if l == letter_to_insert:
                letter_inds = group.shape_ids
                return letter_inds[0], letter_inds[-1], len(letter_inds)

    def reset(self):
        points = torch.cat([point.clone().detach() for point in self.parameters.point])
        self.angles = self.get_angles(points)

    def init_faces(self, device: torch.device) -> torch.tensor:
        faces_ = []
        for j, c in enumerate(self.target_letter):
            points_np = [self.parameters.point[i].clone().detach().cpu().numpy() for i in range(len(self.parameters.point))]
            start_ind, end_ind, shapes_per_letter = self.get_letter_inds(c)
            print(c, start_ind, end_ind)
            holes = []
            if shapes_per_letter > 1:
                holes = points_np[start_ind+1:end_ind]
            poly = Polygon(points_np[start_ind], holes=holes)
            poly = poly.buffer(0)
            points_np = np.concatenate(points_np)
            faces = Delaunay(points_np).simplices
            is_intersect = np.array([poly.contains(Point(points_np[face].mean(0))) for face in faces], dtype=np.bool_)
            faces_.append(torch.from_numpy(faces[is_intersect]).to(device, dtype=torch.int64))
        return faces_

    def __call__(self) -> torch.Tensor:
        loss_angles = 0
        points = torch.cat(self.parameters.point)
        angles = self.get_angles(points)
        for i in range(len(self.faces)):
            loss_angles += (nnf.mse_loss(angles[i], self.angles[i]))
        return loss_angles