File size: 32,348 Bytes
c673f60
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
import random
import numpy as np
from tqdm import tqdm
import os
import torch
import torch.nn as nn
import torch.nn.functional as F
import numpy as np
from einops import repeat
import time
from tools.torch_tools import wav_to_fbank, sinusoidal_positional_embedding

from audioldm.audio.stft import TacotronSTFT
from audioldm.variational_autoencoder import AutoencoderKL
from audioldm.utils import default_audioldm_config, get_metadata

from transformers import CLIPTokenizer, AutoTokenizer, T5Tokenizer
from transformers import CLIPTextModel, T5EncoderModel, AutoModel
from transformers import CLIPVisionModelWithProjection, CLIPTextModelWithProjection
from transformers import CLIPProcessor, CLIPModel

import diffusers
from diffusers.utils.torch_utils import randn_tensor
from diffusers import DDPMScheduler, UNet2DConditionModel
from diffusers import AutoencoderKL as DiffuserAutoencoderKL
from torchvision.transforms import Compose, Resize, CenterCrop, ToTensor, Normalize, InterpolationMode, RandomResizedCrop
from diffusers import AudioLDMPipeline

def build_pretrained_models(name):
    checkpoint = torch.load(name, map_location="cpu")
    scale_factor = checkpoint["state_dict"]["scale_factor"].item()

    vae_state_dict = {k[18:]: v for k, v in checkpoint["state_dict"].items() if "first_stage_model." in k}

    config = default_audioldm_config(name)
    vae_config = config["model"]["params"]["first_stage_config"]["params"]
    vae_config["scale_factor"] = scale_factor

    vae = AutoencoderKL(**vae_config)
    vae.load_state_dict(vae_state_dict)

    fn_STFT = TacotronSTFT(
        config["preprocessing"]["stft"]["filter_length"],
        config["preprocessing"]["stft"]["hop_length"],
        config["preprocessing"]["stft"]["win_length"],
        config["preprocessing"]["mel"]["n_mel_channels"],
        config["preprocessing"]["audio"]["sampling_rate"],
        config["preprocessing"]["mel"]["mel_fmin"],
        config["preprocessing"]["mel"]["mel_fmax"],
    )

    vae.eval()
    fn_STFT.eval()
    return vae, fn_STFT


class EffNetb3(nn.Module):
    def __init__(self, pretrained_model_path, embedding_dim=1024, pretrained=True):
        super(EffNetb3, self).__init__()
        self.model_name = 'effnetb3'
        self.pretrained = pretrained
        # Create model
        # self.effnet = torch.hub.load('rwightman/gen-efficientnet-pytorch', 'efficientnet_b3', pretrained=self.pretrained)
        # torch.save(self.effnet, 'model.pth')
        self.effnet = torch.hub.load(pretrained_model_path, 'efficientnet_b3', trust_repo=True, source='local')
        #self.effnet.conv_stem = nn.Conv2d(1, 40, kernel_size=(3, 3), stride=(2, 2), padding=(1, 1), bias=False)
        self.embedder = nn.Conv2d(384, embedding_dim, kernel_size=1, stride=1, padding=0)

    def forward(self, x):
        #out = self.effnet(x)
        out = self.effnet.conv_stem(x)
        out = self.effnet.bn1(out)
        out = self.effnet.act1(out)
        for i in range(len(self.effnet.blocks)):
            out = self.effnet.blocks[i](out)
        out = self.embedder(out)
        return out


class EffNetb3_last_layer(nn.Module):
    def __init__(self, pretrained_model_path, embedding_dim=1024, pretrained=True):
        super(EffNetb3_last_layer, self).__init__()
        self.model_name = 'effnetb3'
        self.pretrained = pretrained
        self.effnet = torch.hub.load(pretrained_model_path, 'efficientnet_b3', trust_repo=True, source='local')
        self.effnet.classifier = nn.Linear(1536, embedding_dim)

    def forward(self, x):
        out = self.effnet(x)
        return out.unsqueeze(-1)


class Clip4Video(nn.Module):
    def __init__(self, model, embedding_dim=1024, pretrained=True, pe=False):
        super(Clip4Video, self).__init__()
        self.pretrained = pretrained
        self.clip_vision = CLIPVisionModelWithProjection.from_pretrained(model)
        self.clip_text = CLIPTextModelWithProjection.from_pretrained(model)
        self.tokenizer = AutoTokenizer.from_pretrained(model)

        input_dim = 512 if "clip-vit-base" in model else 768
        self.linear_layer = nn.Linear(input_dim, embedding_dim)
        self.pe = sinusoidal_positional_embedding(30, input_dim) if pe else None
        print("*****PE*****") if pe else print("*****W/O PE*****")

    def forward(self, text=None, image=None, video=None):
        assert text is not None or image is not None or video is not None, "At least one of text, image or video should be provided"
        if text is not None and video is None:
            inputs = self.tokenizer([text], padding=True, truncation=True, return_tensors="pt", max_length=77).to(self.clip_text.device)
            out = self.clip_text(**inputs)
            out = out.text_embeds.repeat(20, 1)
        elif video is not None and text is None:
            out = self.clip_vision(video.to(self.clip_vision.device))          # input video x: t * 3 * w * h
            out = out.image_embeds        # t * 512
            if self.pe is not None:
                out = out + self.pe[:out.shape[0], :].to(self.clip_vision.device)
            # out['last_hidden_state'].shape # t * 50 * 768
            # out['image_embeds'].shape      # t * 512
        elif text is not None and video is not None:
            text_inputs = self.tokenizer([text], padding=True, truncation=True, return_tensors="pt", max_length=77).to(self.clip_text.device)
            video_out = self.clip_vision(video.to(self.clip_vision.device))
            video_out = video_out.image_embeds
            text_out = self.clip_text(**text_inputs)
            text_out = text_out.text_embeds.repeat(video_out.shape[0], 1)
            # out = text_out + video_out
            # concat 
            out = torch.cat([text_out, video_out], dim=0)
        out = self.linear_layer(out)     # t * 1024
        return out


class AudioDiffusion(nn.Module):
    def __init__(
        self,
        fea_encoder_name,
        scheduler_name,
        unet_model_name=None,
        unet_model_config_path=None,
        snr_gamma=None,
        freeze_text_encoder=True,
        uncondition=False,
        img_pretrained_model_path=None,
        task=None,
        embedding_dim=1024,
        pe=False
    ):
        super().__init__()

        assert unet_model_name is not None or unet_model_config_path is not None, "Either UNet pretrain model name or a config file path is required"

        self.fea_encoder_name = fea_encoder_name
        self.scheduler_name = scheduler_name
        self.unet_model_name = unet_model_name
        self.unet_model_config_path = unet_model_config_path
        self.snr_gamma = snr_gamma
        self.freeze_text_encoder = freeze_text_encoder
        self.uncondition = uncondition
        self.task = task
        self.pe = pe

        # https://huggingface.co/docs/diffusers/v0.14.0/en/api/schedulers/overview
        self.noise_scheduler = DDPMScheduler.from_pretrained(self.scheduler_name, subfolder="scheduler")
        self.inference_scheduler = DDPMScheduler.from_pretrained(self.scheduler_name, subfolder="scheduler")

        if unet_model_config_path:
            unet_config = UNet2DConditionModel.load_config(unet_model_config_path)
            print("unet_config", unet_config)
            self.unet = UNet2DConditionModel.from_config(unet_config, subfolder="unet")
            self.set_from = "random"
            print("UNet initialized randomly.")
        else:
            self.unet = UNet2DConditionModel.from_pretrained(unet_model_name, subfolder="unet")
            self.set_from = "pre-trained"
            self.group_in = nn.Sequential(nn.Linear(8, 512), nn.Linear(512, 4))
            self.group_out = nn.Sequential(nn.Linear(4, 512), nn.Linear(512, 8))
            print("UNet initialized from stable diffusion checkpoint.")

        if self.task == "text2audio":
            if "stable-diffusion" in self.fea_encoder_name:
                self.tokenizer = CLIPTokenizer.from_pretrained(self.fea_encoder_name, subfolder="tokenizer")
                self.text_encoder = CLIPTextModel.from_pretrained(self.fea_encoder_name, subfolder="text_encoder")
            elif "t5" in self.fea_encoder_name and "Chinese" not in self.fea_encoder_name:
                self.tokenizer = AutoTokenizer.from_pretrained(self.fea_encoder_name)
                self.text_encoder = T5EncoderModel.from_pretrained(self.fea_encoder_name)
            elif "Chinese" in self.fea_encoder_name:
                self.tokenizer = T5Tokenizer.from_pretrained(self.fea_encoder_name)
                self.text_encoder = T5EncoderModel.from_pretrained(self.fea_encoder_name)
            elif "clap" in self.fea_encoder_name:
                self.tokenizer = RobertaTokenizer.from_pretrained("roberta-base")
                self.CLAP_model = laion_clap.CLAP_Module(enable_fusion=False)
                self.CLAP_model.load_ckpt(self.fea_encoder_name)
            elif "clip-vit" in self.fea_encoder_name:
                # self.CLIP_model = CLIPModel.from_pretrained(self.fea_encoder_name)
                # self.CLIP_processor = CLIPProcessor.from_pretrained(self.fea_encoder_name)
                self.CLIP_model = CLIPTextModelWithProjection.from_pretrained(self.fea_encoder_name)
                self.tokenizer = AutoTokenizer.from_pretrained(self.fea_encoder_name)
                if "base" in self.fea_encoder_name:
                    self.linear_layer = nn.Linear(512, embedding_dim)
                else:
                    self.linear_layer = nn.Linear(768, embedding_dim)
            else:
                self.tokenizer = AutoTokenizer.from_pretrained(self.fea_encoder_name)
                self.text_encoder = AutoModel.from_pretrained(self.fea_encoder_name)
        elif self.task == "image2audio":
            if "clip-vit" in self.fea_encoder_name:
                self.CLIP_model = CLIPModel.from_pretrained(self.fea_encoder_name)
                self.CLIP_processor = CLIPProcessor.from_pretrained(self.fea_encoder_name)
                self.linear_layer = nn.Linear(512, embedding_dim)
            # self.img_fea_extractor = EffNetb3(img_pretrained_model_path)
            else:
                self.img_fea_extractor = EffNetb3_last_layer(img_pretrained_model_path)
        elif self.task == "video2audio":
            self.vid_fea_extractor = Clip4Video(model=self.fea_encoder_name, embedding_dim=embedding_dim, pe=pe)

    def compute_snr(self, timesteps):
        """
        Computes SNR as per https://github.com/TiankaiHang/Min-SNR-Diffusion-Training/blob/521b624bd70c67cee4bdf49225915f5945a872e3/guided_diffusion/gaussian_diffusion.py#L847-L849
        """
        alphas_cumprod = self.noise_scheduler.alphas_cumprod
        sqrt_alphas_cumprod = alphas_cumprod**0.5
        sqrt_one_minus_alphas_cumprod = (1.0 - alphas_cumprod) ** 0.5

        # Expand the tensors.
        # Adapted from https://github.com/TiankaiHang/Min-SNR-Diffusion-Training/blob/521b624bd70c67cee4bdf49225915f5945a872e3/guided_diffusion/gaussian_diffusion.py#L1026
        sqrt_alphas_cumprod = sqrt_alphas_cumprod.to(device=timesteps.device)[timesteps].float()
        while len(sqrt_alphas_cumprod.shape) < len(timesteps.shape):
            sqrt_alphas_cumprod = sqrt_alphas_cumprod[..., None]
        alpha = sqrt_alphas_cumprod.expand(timesteps.shape)

        sqrt_one_minus_alphas_cumprod = sqrt_one_minus_alphas_cumprod.to(device=timesteps.device)[timesteps].float()
        while len(sqrt_one_minus_alphas_cumprod.shape) < len(timesteps.shape):
            sqrt_one_minus_alphas_cumprod = sqrt_one_minus_alphas_cumprod[..., None]
        sigma = sqrt_one_minus_alphas_cumprod.expand(timesteps.shape)

        # Compute SNR.
        snr = (alpha / sigma) ** 2
        return snr

    def encode_text(self, prompt):
        device = self.text_encoder.device
        batch = self.tokenizer(
            prompt, max_length=self.tokenizer.model_max_length, padding=True, truncation=True, return_tensors="pt"
        )
        input_ids, attention_mask = batch.input_ids.to(device), batch.attention_mask.to(device)

        if self.freeze_text_encoder:
            with torch.no_grad():
                encoder_hidden_states = self.text_encoder(
                    input_ids=input_ids, attention_mask=attention_mask
                )[0]
        else:
            encoder_hidden_states = self.text_encoder(
                input_ids=input_ids, attention_mask=attention_mask
            )[0]

        boolean_encoder_mask = (attention_mask == 1).to(device)
        return encoder_hidden_states, boolean_encoder_mask

    def encode_text_CLAP(self, prompt):
        device = self.text_encoder.device
        batch = self.tokenizer(prompt, padding="max_length", truncation=True, max_length=self.tokenizer.model_max_length, return_tensors="pt")
        input_ids, attention_mask = batch.input_ids.to(device), batch.attention_mask.to(device)

        if self.freeze_text_encoder:
            with torch.no_grad():
                encoder_hidden_states = self.CLAP_model.model.get_text_embedding(prompt)
        else:
            encoder_hidden_states = self.CLAP_model.model.get_text_embedding(prompt)

        boolean_encoder_mask = (attention_mask == 1).to(device)
        return encoder_hidden_states, boolean_encoder_mask

    def encode_image(self, prompt, device):
        if "clip-vit" in self.fea_encoder_name:
            with torch.no_grad():
                inputs = self.CLIP_processor(text=["aaa"], images=prompt, return_tensors="pt", padding=True).to(device)
                encoder_hidden_states = self.CLIP_model(**inputs).image_embeds
            encoder_hidden_states = self.linear_layer(encoder_hidden_states)    # b * 1024
            encoder_hidden_states = encoder_hidden_states.unsqueeze(1).to(device)
        else:
            img_fea = self.img_fea_extractor(prompt) 
            encoder_hidden_states = img_fea.view(img_fea.shape[0], img_fea.shape[1], -1).permute(0, 2, 1)
        boolean_encoder_mask = torch.ones((encoder_hidden_states.shape[0], encoder_hidden_states.shape[1]), dtype=torch.bool)
        boolean_encoder_mask = boolean_encoder_mask.to(device)

        return encoder_hidden_states, boolean_encoder_mask
    
    def encode_video(self, video_batch, text=None, device=None):
        vid_feas = []
        for i, video in enumerate(video_batch):
            if text:
                vid_fea = self.vid_fea_extractor(video=video, text=text[i]) # t * fea_dim
            else:
                vid_fea = self.vid_fea_extractor(video=video)
            vid_feas.append(vid_fea)
        
        padding = 0
        size = max(v.size(0) for v in vid_feas)
        batch_size = len(vid_feas)
        embed_size = vid_feas[0].size(1)
        encoder_hidden_states = vid_feas[0].new(batch_size, size, embed_size).fill_(padding)
        boolean_encoder_mask = torch.ones((batch_size, size), dtype=torch.bool)

        def copy_tensor(src, dst):
            assert dst.numel() == src.numel()
            dst.copy_(src)

        for i, v in enumerate(vid_feas):
            copy_tensor(v, encoder_hidden_states[i][: len(v)])
            boolean_encoder_mask[i, len(v):] = False    
        return encoder_hidden_states.to(device), boolean_encoder_mask.to(device)

    def encode_text_CLIP(self, prompt, device):
        # tmp_image = np.ones((512, 512, 3))
        # with torch.no_grad():
        #     inputs = self.CLIP_processor(text=prompt, images=tmp_image, return_tensors="pt", padding=True, max_length=77, truncation=True).to(device)
        #     encoder_hidden_states = self.CLIP_model(**inputs).text_embeds   # b * 768
        text_inputs = self.tokenizer(prompt, padding=True, truncation=True, return_tensors="pt", max_length=77).to(device)
        encoder_hidden_states = self.CLIP_model(**text_inputs).text_embeds
        encoder_hidden_states = self.linear_layer(encoder_hidden_states)    # b * 1024
        encoder_hidden_states = encoder_hidden_states.unsqueeze(1).to(device)
        boolean_encoder_mask = torch.ones((encoder_hidden_states.shape[0], encoder_hidden_states.shape[1]), dtype=torch.bool)
        boolean_encoder_mask = boolean_encoder_mask.to(device)

        return encoder_hidden_states, boolean_encoder_mask

    def forward(self, latents, text=None, video=None, image=None, validation_mode=False, device=None):
        num_train_timesteps = self.noise_scheduler.num_train_timesteps
        self.noise_scheduler.set_timesteps(num_train_timesteps, device=device)
        # encoder_hidden_states.shape  [b, t, f]
        if self.task == "text2audio":
            if "clip-vit" in self.fea_encoder_name:
                encoder_hidden_states, boolean_encoder_mask = self.encode_text_CLIP(text, device)
            else:
                encoder_hidden_states, boolean_encoder_mask = self.encode_text(text)
            if self.uncondition:
                mask_indices = [k for k in range(len(text)) if random.random() < 0.1]
                # mask_indices = [k for k in range(len(prompt))]
                if len(mask_indices) > 0:
                    encoder_hidden_states[mask_indices] = 0
        elif self.task == "image2audio":
            encoder_hidden_states, boolean_encoder_mask = self.encode_image(image, device=device)
        elif self.task == "video2audio":
            encoder_hidden_states, boolean_encoder_mask = self.encode_video(video, text, device=device)
        
        bsz = latents.shape[0]
        if validation_mode:
            timesteps = (self.noise_scheduler.num_train_timesteps//2) * torch.ones((bsz,), dtype=torch.int64, device=device)
        else:
            # Sample a random timestep for each instance
            timesteps = torch.randint(0, self.noise_scheduler.num_train_timesteps, (bsz,), device=device)
        timesteps = timesteps.long()

        noise = torch.randn_like(latents)
        noisy_latents = self.noise_scheduler.add_noise(latents, noise, timesteps)

        # Get the target for loss depending on the prediction type
        if self.noise_scheduler.config.prediction_type == "epsilon":
            target = noise
        elif self.noise_scheduler.config.prediction_type == "v_prediction":
            target = self.noise_scheduler.get_velocity(latents, noise, timesteps)
        else:
            raise ValueError(f"Unknown prediction type {self.noise_scheduler.config.prediction_type}")

        if self.set_from == "random":
            model_pred = self.unet(
                noisy_latents, timesteps, encoder_hidden_states, 
                encoder_attention_mask=boolean_encoder_mask
            ).sample

        elif self.set_from == "pre-trained":
            compressed_latents = self.group_in(noisy_latents.permute(0, 2, 3, 1).contiguous()).permute(0, 3, 1, 2).contiguous()
            model_pred = self.unet(
                compressed_latents, timesteps, encoder_hidden_states, 
                encoder_attention_mask=boolean_encoder_mask
            ).sample
            model_pred = self.group_out(model_pred.permute(0, 2, 3, 1).contiguous()).permute(0, 3, 1, 2).contiguous()

        if self.snr_gamma is None:
            loss = F.mse_loss(model_pred.float(), target.float(), reduction="mean")
        else:
            # Compute loss-weights as per Section 3.4 of https://arxiv.org/abs/2303.09556.
            # Adaptef from huggingface/diffusers/blob/main/examples/text_to_image/train_text_to_image.py
            snr = self.compute_snr(timesteps)
            mse_loss_weights = (
                torch.stack([snr, self.snr_gamma * torch.ones_like(timesteps)], dim=1).min(dim=1)[0] / snr
            )
            loss = F.mse_loss(model_pred.float(), target.float(), reduction="none")
            loss = loss.mean(dim=list(range(1, len(loss.shape)))) * mse_loss_weights
            loss = loss.mean()

        return loss

    @torch.no_grad()
    def inference(self, inference_scheduler, text=None, video=None, image=None, num_steps=20, guidance_scale=3, num_samples_per_prompt=1, 
                  disable_progress=True, device=None):
        start = time.time()
        classifier_free_guidance = guidance_scale > 1.0

        #print("ldm time 0", time.time()-start, prompt)
        if self.task == "text2audio":
            batch_size = len(text) * num_samples_per_prompt

            if classifier_free_guidance:
                if "clip-vit" in self.fea_encoder_name:
                    encoder_hidden_states, boolean_encoder_mask = self.encode_text_clip_classifier_free(text, num_samples_per_prompt, device=device)
                else:
                    encoder_hidden_states, boolean_encoder_mask = self.encode_text_classifier_free(text, num_samples_per_prompt)
            else:
                encoder_hidden_states, boolean_encoder_mask = self.encode_text(text)
                encoder_hidden_states = encoder_hidden_states.repeat_interleave(num_samples_per_prompt, 0)
                boolean_encoder_mask = boolean_encoder_mask.repeat_interleave(num_samples_per_prompt, 0)
        elif self.task == "image2audio":
            if classifier_free_guidance:
                encoder_hidden_states, boolean_encoder_mask = self.encode_image_classifier_free(image, num_samples_per_prompt, device=device)
            else:
                encoder_hidden_states, boolean_encoder_mask = self.encode_image_no_grad(image, device=device)
                encoder_hidden_states = encoder_hidden_states.repeat_interleave(num_samples_per_prompt, 0)
                boolean_encoder_mask = boolean_encoder_mask.repeat_interleave(num_samples_per_prompt, 0)
        elif self.task == "video2audio":
            batch_size = len(video) * num_samples_per_prompt
            encoder_hidden_states, boolean_encoder_mask = self.encode_video_classifier_free(video, text, num_samples_per_prompt, device=device)
        # import pdb;pdb.set_trace()
        #print("ldm time 1", time.time()-start)
        inference_scheduler.set_timesteps(num_steps, device=device)
        timesteps = inference_scheduler.timesteps

        num_channels_latents = self.unet.in_channels
        latents = self.prepare_latents(batch_size, inference_scheduler, num_channels_latents, encoder_hidden_states.dtype, device)
        num_warmup_steps = len(timesteps) - num_steps * inference_scheduler.order
        progress_bar = tqdm(range(num_steps), disable=disable_progress)

        #print("ldm time 2", time.time()-start, timesteps)
        for i, t in enumerate(timesteps):
            # expand the latents if we are doing classifier free guidance
            latent_model_input = torch.cat([latents] * 2) if classifier_free_guidance else latents
            latent_model_input = inference_scheduler.scale_model_input(latent_model_input, t)

            #print("ldm emu", i, time.time()-start)
            noise_pred = self.unet(
                latent_model_input, t, encoder_hidden_states=encoder_hidden_states,
                encoder_attention_mask=boolean_encoder_mask
            ).sample

            # perform guidance
            if 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)

            # compute the previous noisy sample x_t -> x_t-1
            latents = inference_scheduler.step(noise_pred, t, latents).prev_sample

            # call the callback, if provided
            if i == len(timesteps) - 1 or ((i + 1) > num_warmup_steps and (i + 1) % inference_scheduler.order == 0):
                progress_bar.update(1)

        #print("ldm time 3", time.time()-start)
        if self.set_from == "pre-trained":
            latents = self.group_out(latents.permute(0, 2, 3, 1).contiguous()).permute(0, 3, 1, 2).contiguous()
        return latents

    def prepare_latents(self, batch_size, inference_scheduler, num_channels_latents, dtype, device):
        shape = (batch_size, num_channels_latents, 256, 16)
        latents = randn_tensor(shape, generator=None, device=device, dtype=dtype)
        # scale the initial noise by the standard deviation required by the scheduler
        latents = latents * inference_scheduler.init_noise_sigma
        return latents

    def encode_text_classifier_free(self, prompt, num_samples_per_prompt):
        device = self.text_encoder.device
        batch = self.tokenizer(
            prompt, max_length=self.tokenizer.model_max_length, padding=True, truncation=True, return_tensors="pt"
        )
        input_ids, attention_mask = batch.input_ids.to(device), batch.attention_mask.to(device)

        with torch.no_grad():
            prompt_embeds = self.text_encoder(
                input_ids=input_ids, attention_mask=attention_mask
            )[0]
                
        prompt_embeds = prompt_embeds.repeat_interleave(num_samples_per_prompt, 0)
        attention_mask = attention_mask.repeat_interleave(num_samples_per_prompt, 0)

        # get unconditional embeddings for classifier free guidance
        uncond_tokens = [""] * len(prompt)

        max_length = prompt_embeds.shape[1]
        uncond_batch = self.tokenizer(
            uncond_tokens, max_length=max_length, padding="max_length", truncation=True, return_tensors="pt",
        )
        uncond_input_ids = uncond_batch.input_ids.to(device)
        uncond_attention_mask = uncond_batch.attention_mask.to(device)

        with torch.no_grad():
            negative_prompt_embeds = self.text_encoder(
                input_ids=uncond_input_ids, attention_mask=uncond_attention_mask
            )[0]
                
        negative_prompt_embeds = negative_prompt_embeds.repeat_interleave(num_samples_per_prompt, 0)
        uncond_attention_mask = uncond_attention_mask.repeat_interleave(num_samples_per_prompt, 0)

        # For classifier free guidance, we need to do two forward passes.
        # We concatenate the unconditional and text embeddings into a single batch to avoid doing two forward passes
        prompt_embeds = torch.cat([negative_prompt_embeds, prompt_embeds])
        prompt_mask = torch.cat([uncond_attention_mask, attention_mask])
        boolean_prompt_mask = (prompt_mask == 1).to(device)

        # import pdb;pdb.set_trace()
        return prompt_embeds, boolean_prompt_mask

    def encode_image_no_grad(self, prompt, device):
        with torch.no_grad():
            img_fea = self.img_fea_extractor(prompt) 
        encoder_hidden_states = img_fea.view(img_fea.shape[0], img_fea.shape[1], -1).permute(0, 2, 1)
        boolean_encoder_mask = torch.ones((encoder_hidden_states.shape[0], encoder_hidden_states.shape[1]), dtype=torch.bool)
        boolean_encoder_mask = boolean_encoder_mask.to(device)

        return encoder_hidden_states, boolean_encoder_mask
    
    def encode_text_clip_classifier_free(self, prompt, num_samples_per_prompt, device):
        # 如果想测试输入文本的效果,就用下面两行
        with torch.no_grad():
            encoder_hidden_states, boolean_encoder_mask = self.encode_text_CLIP(prompt, device)
        # if "clip-vit" in self.fea_encoder_name:
        #     with torch.no_grad():
        #         inputs = self.CLIP_processor(text=['aaa'], images=prompt, return_tensors="pt", padding=True).to(device)
        #         encoder_hidden_states = self.CLIP_model(**inputs).image_embeds   # b * 768
        #         encoder_hidden_states = self.linear_layer(encoder_hidden_states)    # b * 1024
        #         encoder_hidden_states = encoder_hidden_states.unsqueeze(1).to(device)
        #         boolean_encoder_mask = torch.ones((encoder_hidden_states.shape[0], encoder_hidden_states.shape[1]), dtype=torch.bool)
        #         boolean_encoder_mask = boolean_encoder_mask.to(device)

        b, t, n = encoder_hidden_states.shape
        attention_mask = boolean_encoder_mask.to(device)
        prompt_embeds = encoder_hidden_states.repeat_interleave(num_samples_per_prompt, 0)
        attention_mask = attention_mask.repeat_interleave(num_samples_per_prompt, 0)

        negative_prompt_embeds = encoder_hidden_states.new(b, t, n).fill_(0)
        uncond_attention_mask = torch.ones((b, t), dtype=torch.bool).to(device)

        negative_prompt_embeds = negative_prompt_embeds.repeat_interleave(num_samples_per_prompt, 0)
        uncond_attention_mask = uncond_attention_mask.repeat_interleave(num_samples_per_prompt, 0)

        # For classifier free guidance, we need to do two forward passes.
        # We concatenate the unconditional and text embeddings into a single batch to avoid doing two forward passes
        prompt_embeds = torch.cat([negative_prompt_embeds, prompt_embeds])
        boolean_prompt_mask = torch.cat([uncond_attention_mask, attention_mask])

        return prompt_embeds.to(device), boolean_prompt_mask.to(device)


    def encode_image_classifier_free(self, prompt, num_samples_per_prompt, device):
        with torch.no_grad():
            if "clip-vit" in self.fea_encoder_name:
                inputs = self.CLIP_processor(text=["aaa"], images=prompt, return_tensors="pt", padding=True).to(device)
                img_fea = self.CLIP_model(**inputs).image_embeds
                img_fea = self.linear_layer(img_fea)
            else:
                img_fea = self.img_fea_extractor(prompt) 
        encoder_hidden_states = img_fea.view(img_fea.shape[0], img_fea.shape[1], -1).permute(0, 2, 1)
        b, t, n = encoder_hidden_states.shape
        boolean_encoder_mask = torch.ones((b, t), dtype=torch.bool)
        attention_mask = boolean_encoder_mask.to(device)
        prompt_embeds = encoder_hidden_states.repeat_interleave(num_samples_per_prompt, 0)
        attention_mask = attention_mask.repeat_interleave(num_samples_per_prompt, 0)

        negative_prompt_embeds = encoder_hidden_states.new(b, t, n).fill_(0)
        uncond_attention_mask = torch.ones((b, t), dtype=torch.bool).to(device)

        negative_prompt_embeds = negative_prompt_embeds.repeat_interleave(num_samples_per_prompt, 0)
        uncond_attention_mask = uncond_attention_mask.repeat_interleave(num_samples_per_prompt, 0)

        # For classifier free guidance, we need to do two forward passes.
        # We concatenate the unconditional and text embeddings into a single batch to avoid doing two forward passes
        prompt_embeds = torch.cat([negative_prompt_embeds, prompt_embeds])
        boolean_prompt_mask = torch.cat([uncond_attention_mask, attention_mask])

        return prompt_embeds.to(device), boolean_prompt_mask.to(device)
    
    def encode_video_classifier_free(self, video_batch, text_batch, num_samples_per_prompt, device):
        vid_feas = []
        for i, video in enumerate(video_batch):
            if text_batch:
                vid_fea = self.vid_fea_extractor(video=video.to(device), text=text_batch[i])
            else:
                vid_fea = self.vid_fea_extractor(video=video.to(device))
            vid_feas.append(vid_fea)
        
        padding = 0
        size = max(v.size(0) for v in vid_feas)
        batch_size = len(vid_feas)
        embed_size = vid_feas[0].size(1)
        encoder_hidden_states = vid_feas[0].new(batch_size, size, embed_size).fill_(padding)
        boolean_encoder_mask = torch.ones((batch_size, size), dtype=torch.bool)

        def copy_tensor(src, dst):
            assert dst.numel() == src.numel()
            dst.copy_(src)

        for i, v in enumerate(vid_feas):
            copy_tensor(v, encoder_hidden_states[i][: len(v)])
            boolean_encoder_mask[i, len(v):] = False    

        b, t, n = encoder_hidden_states.shape
        negative_prompt_embeds = encoder_hidden_states.new(b, t, n).fill_(0)
        uncond_attention_mask = torch.ones((b, t), dtype=torch.bool)

        negative_prompt_embeds = negative_prompt_embeds.repeat_interleave(num_samples_per_prompt, 0)
        uncond_attention_mask = uncond_attention_mask.repeat_interleave(num_samples_per_prompt, 0)

        # For classifier free guidance, we need to do two forward passes.
        # We concatenate the unconditional and text embeddings into a single batch to avoid doing two forward passes
        encoder_hidden_states = torch.cat([negative_prompt_embeds, encoder_hidden_states])
        boolean_encoder_mask = torch.cat([uncond_attention_mask, boolean_encoder_mask])

        return encoder_hidden_states.to(device), boolean_encoder_mask.to(device)