| | """ |
| | This script performs DDIM inversion for video frames using a pre-trained model and generates |
| | a video reconstruction based on a provided prompt. It utilizes the CogVideoX pipeline to |
| | process video frames, apply the DDIM inverse scheduler, and produce an output video. |
| | |
| | **Please notice that this script is based on the CogVideoX 5B model, and would not generate |
| | a good result for 2B variants.** |
| | |
| | Usage: |
| | python cogvideox_ddim_inversion.py |
| | --model-path /path/to/model |
| | --prompt "a prompt" |
| | --video-path /path/to/video.mp4 |
| | --output-path /path/to/output |
| | |
| | For more details about the cli arguments, please run `python cogvideox_ddim_inversion.py --help`. |
| | |
| | Author: |
| | LittleNyima <littlenyima[at]163[dot]com> |
| | """ |
| |
|
| | import argparse |
| | import math |
| | import os |
| | from typing import Any, Dict, List, Optional, Tuple, TypedDict, Union, cast |
| |
|
| | import torch |
| | import torch.nn.functional as F |
| | import torchvision.transforms as T |
| | from transformers import T5EncoderModel, T5Tokenizer |
| |
|
| | from diffusers.models.attention_processor import Attention, CogVideoXAttnProcessor2_0 |
| | from diffusers.models.autoencoders import AutoencoderKLCogVideoX |
| | from diffusers.models.embeddings import apply_rotary_emb |
| | from diffusers.models.transformers.cogvideox_transformer_3d import CogVideoXBlock, CogVideoXTransformer3DModel |
| | from diffusers.pipelines.cogvideo.pipeline_cogvideox import CogVideoXPipeline, retrieve_timesteps |
| | from diffusers.schedulers import CogVideoXDDIMScheduler, DDIMInverseScheduler |
| | from diffusers.utils import export_to_video |
| |
|
| |
|
| | |
| | |
| | import decord |
| |
|
| |
|
| | class DDIMInversionArguments(TypedDict): |
| | model_path: str |
| | prompt: str |
| | video_path: str |
| | output_path: str |
| | guidance_scale: float |
| | num_inference_steps: int |
| | skip_frames_start: int |
| | skip_frames_end: int |
| | frame_sample_step: Optional[int] |
| | max_num_frames: int |
| | width: int |
| | height: int |
| | fps: int |
| | dtype: torch.dtype |
| | seed: int |
| | device: torch.device |
| |
|
| |
|
| | def get_args() -> DDIMInversionArguments: |
| | parser = argparse.ArgumentParser() |
| |
|
| | parser.add_argument("--model_path", type=str, required=True, help="Path of the pretrained model") |
| | parser.add_argument("--prompt", type=str, required=True, help="Prompt for the direct sample procedure") |
| | parser.add_argument("--video_path", type=str, required=True, help="Path of the video for inversion") |
| | parser.add_argument("--output_path", type=str, default="output", help="Path of the output videos") |
| | parser.add_argument("--guidance_scale", type=float, default=6.0, help="Classifier-free guidance scale") |
| | parser.add_argument("--num_inference_steps", type=int, default=50, help="Number of inference steps") |
| | parser.add_argument("--skip_frames_start", type=int, default=0, help="Number of skipped frames from the start") |
| | parser.add_argument("--skip_frames_end", type=int, default=0, help="Number of skipped frames from the end") |
| | parser.add_argument("--frame_sample_step", type=int, default=None, help="Temporal stride of the sampled frames") |
| | parser.add_argument("--max_num_frames", type=int, default=81, help="Max number of sampled frames") |
| | parser.add_argument("--width", type=int, default=720, help="Resized width of the video frames") |
| | parser.add_argument("--height", type=int, default=480, help="Resized height of the video frames") |
| | parser.add_argument("--fps", type=int, default=8, help="Frame rate of the output videos") |
| | parser.add_argument("--dtype", type=str, default="bf16", choices=["bf16", "fp16"], help="Dtype of the model") |
| | parser.add_argument("--seed", type=int, default=42, help="Seed for the random number generator") |
| | parser.add_argument("--device", type=str, default="cuda", choices=["cuda", "cpu"], help="Device for inference") |
| |
|
| | args = parser.parse_args() |
| | args.dtype = torch.bfloat16 if args.dtype == "bf16" else torch.float16 |
| | args.device = torch.device(args.device) |
| |
|
| | return DDIMInversionArguments(**vars(args)) |
| |
|
| |
|
| | class CogVideoXAttnProcessor2_0ForDDIMInversion(CogVideoXAttnProcessor2_0): |
| | def __init__(self): |
| | super().__init__() |
| |
|
| | def calculate_attention( |
| | self, |
| | query: torch.Tensor, |
| | key: torch.Tensor, |
| | value: torch.Tensor, |
| | attn: Attention, |
| | batch_size: int, |
| | image_seq_length: int, |
| | text_seq_length: int, |
| | attention_mask: Optional[torch.Tensor], |
| | image_rotary_emb: Optional[torch.Tensor], |
| | ) -> Tuple[torch.Tensor, torch.Tensor]: |
| | r""" |
| | Core attention computation with inversion-guided RoPE integration. |
| | |
| | Args: |
| | query (`torch.Tensor`): `[batch_size, seq_len, dim]` query tensor |
| | key (`torch.Tensor`): `[batch_size, seq_len, dim]` key tensor |
| | value (`torch.Tensor`): `[batch_size, seq_len, dim]` value tensor |
| | attn (`Attention`): Parent attention module with projection layers |
| | batch_size (`int`): Effective batch size (after chunk splitting) |
| | image_seq_length (`int`): Length of image feature sequence |
| | text_seq_length (`int`): Length of text feature sequence |
| | attention_mask (`Optional[torch.Tensor]`): Attention mask tensor |
| | image_rotary_emb (`Optional[torch.Tensor]`): Rotary embeddings for image positions |
| | |
| | Returns: |
| | `Tuple[torch.Tensor, torch.Tensor]`: |
| | (1) hidden_states: [batch_size, image_seq_length, dim] processed image features |
| | (2) encoder_hidden_states: [batch_size, text_seq_length, dim] processed text features |
| | """ |
| | inner_dim = key.shape[-1] |
| | head_dim = inner_dim // attn.heads |
| |
|
| | query = query.view(batch_size, -1, attn.heads, head_dim).transpose(1, 2) |
| | key = key.view(batch_size, -1, attn.heads, head_dim).transpose(1, 2) |
| | value = value.view(batch_size, -1, attn.heads, head_dim).transpose(1, 2) |
| |
|
| | if attn.norm_q is not None: |
| | query = attn.norm_q(query) |
| | if attn.norm_k is not None: |
| | key = attn.norm_k(key) |
| |
|
| | |
| | if image_rotary_emb is not None: |
| | query[:, :, text_seq_length:] = apply_rotary_emb(query[:, :, text_seq_length:], image_rotary_emb) |
| | if not attn.is_cross_attention: |
| | if key.size(2) == query.size(2): |
| | key[:, :, text_seq_length:] = apply_rotary_emb(key[:, :, text_seq_length:], image_rotary_emb) |
| | else: |
| | key[:, :, text_seq_length : text_seq_length + image_seq_length] = apply_rotary_emb( |
| | key[:, :, text_seq_length : text_seq_length + image_seq_length], image_rotary_emb |
| | ) |
| | key[:, :, text_seq_length * 2 + image_seq_length :] = apply_rotary_emb( |
| | key[:, :, text_seq_length * 2 + image_seq_length :], image_rotary_emb |
| | ) |
| |
|
| | hidden_states = F.scaled_dot_product_attention( |
| | query, key, value, attn_mask=attention_mask, dropout_p=0.0, is_causal=False |
| | ) |
| |
|
| | hidden_states = hidden_states.transpose(1, 2).reshape(batch_size, -1, attn.heads * head_dim) |
| |
|
| | |
| | hidden_states = attn.to_out[0](hidden_states) |
| | |
| | hidden_states = attn.to_out[1](hidden_states) |
| |
|
| | encoder_hidden_states, hidden_states = hidden_states.split( |
| | [text_seq_length, hidden_states.size(1) - text_seq_length], dim=1 |
| | ) |
| | return hidden_states, encoder_hidden_states |
| |
|
| | def __call__( |
| | self, |
| | attn: Attention, |
| | hidden_states: torch.Tensor, |
| | encoder_hidden_states: torch.Tensor, |
| | attention_mask: Optional[torch.Tensor] = None, |
| | image_rotary_emb: Optional[torch.Tensor] = None, |
| | ) -> Tuple[torch.Tensor, torch.Tensor]: |
| | r""" |
| | Process the dual-path attention for the inversion-guided denoising procedure. |
| | |
| | Args: |
| | attn (`Attention`): Parent attention module |
| | hidden_states (`torch.Tensor`): `[batch_size, image_seq_len, dim]` Image tokens |
| | encoder_hidden_states (`torch.Tensor`): `[batch_size, text_seq_len, dim]` Text tokens |
| | attention_mask (`Optional[torch.Tensor]`): Optional attention mask |
| | image_rotary_emb (`Optional[torch.Tensor]`): Rotary embeddings for image tokens |
| | |
| | Returns: |
| | `Tuple[torch.Tensor, torch.Tensor]`: |
| | (1) Final hidden states: `[batch_size, image_seq_length, dim]` Resulting image tokens |
| | (2) Final encoder states: `[batch_size, text_seq_length, dim]` Resulting text tokens |
| | """ |
| | image_seq_length = hidden_states.size(1) |
| | text_seq_length = encoder_hidden_states.size(1) |
| |
|
| | hidden_states = torch.cat([encoder_hidden_states, hidden_states], dim=1) |
| |
|
| | batch_size, sequence_length, _ = ( |
| | hidden_states.shape if encoder_hidden_states is None else encoder_hidden_states.shape |
| | ) |
| |
|
| | if attention_mask is not None: |
| | attention_mask = attn.prepare_attention_mask(attention_mask, sequence_length, batch_size) |
| | attention_mask = attention_mask.view(batch_size, attn.heads, -1, attention_mask.shape[-1]) |
| |
|
| | query = attn.to_q(hidden_states) |
| | key = attn.to_k(hidden_states) |
| | value = attn.to_v(hidden_states) |
| |
|
| | query, query_reference = query.chunk(2) |
| | key, key_reference = key.chunk(2) |
| | value, value_reference = value.chunk(2) |
| | batch_size = batch_size // 2 |
| |
|
| | hidden_states, encoder_hidden_states = self.calculate_attention( |
| | query=query, |
| | key=torch.cat((key, key_reference), dim=1), |
| | value=torch.cat((value, value_reference), dim=1), |
| | attn=attn, |
| | batch_size=batch_size, |
| | image_seq_length=image_seq_length, |
| | text_seq_length=text_seq_length, |
| | attention_mask=attention_mask, |
| | image_rotary_emb=image_rotary_emb, |
| | ) |
| | hidden_states_reference, encoder_hidden_states_reference = self.calculate_attention( |
| | query=query_reference, |
| | key=key_reference, |
| | value=value_reference, |
| | attn=attn, |
| | batch_size=batch_size, |
| | image_seq_length=image_seq_length, |
| | text_seq_length=text_seq_length, |
| | attention_mask=attention_mask, |
| | image_rotary_emb=image_rotary_emb, |
| | ) |
| |
|
| | return ( |
| | torch.cat((hidden_states, hidden_states_reference)), |
| | torch.cat((encoder_hidden_states, encoder_hidden_states_reference)), |
| | ) |
| |
|
| |
|
| | class OverrideAttnProcessors: |
| | r""" |
| | Context manager for temporarily overriding attention processors in CogVideo transformer blocks. |
| | |
| | Designed for DDIM inversion process, replaces original attention processors with |
| | `CogVideoXAttnProcessor2_0ForDDIMInversion` and restores them upon exit. Uses Python context manager |
| | pattern to safely manage processor replacement. |
| | |
| | Typical usage: |
| | ```python |
| | with OverrideAttnProcessors(transformer): |
| | # Perform DDIM inversion operations |
| | ``` |
| | |
| | Args: |
| | transformer (`CogVideoXTransformer3DModel`): |
| | The transformer model containing attention blocks to be modified. Should have |
| | `transformer_blocks` attribute containing `CogVideoXBlock` instances. |
| | """ |
| |
|
| | def __init__(self, transformer: CogVideoXTransformer3DModel): |
| | self.transformer = transformer |
| | self.original_processors = {} |
| |
|
| | def __enter__(self): |
| | for block in self.transformer.transformer_blocks: |
| | block = cast(CogVideoXBlock, block) |
| | self.original_processors[id(block)] = block.attn1.get_processor() |
| | block.attn1.set_processor(CogVideoXAttnProcessor2_0ForDDIMInversion()) |
| |
|
| | def __exit__(self, _0, _1, _2): |
| | for block in self.transformer.transformer_blocks: |
| | block = cast(CogVideoXBlock, block) |
| | block.attn1.set_processor(self.original_processors[id(block)]) |
| |
|
| |
|
| | def get_video_frames( |
| | video_path: str, |
| | width: int, |
| | height: int, |
| | skip_frames_start: int, |
| | skip_frames_end: int, |
| | max_num_frames: int, |
| | frame_sample_step: Optional[int], |
| | ) -> torch.FloatTensor: |
| | """ |
| | Extract and preprocess video frames from a video file for VAE processing. |
| | |
| | Args: |
| | video_path (`str`): Path to input video file |
| | width (`int`): Target frame width for decoding |
| | height (`int`): Target frame height for decoding |
| | skip_frames_start (`int`): Number of frames to skip at video start |
| | skip_frames_end (`int`): Number of frames to skip at video end |
| | max_num_frames (`int`): Maximum allowed number of output frames |
| | frame_sample_step (`Optional[int]`): |
| | Frame sampling step size. If None, automatically calculated as: |
| | (total_frames - skipped_frames) // max_num_frames |
| | |
| | Returns: |
| | `torch.FloatTensor`: Preprocessed frames in `[F, C, H, W]` format where: |
| | - `F`: Number of frames (adjusted to 4k + 1 for VAE compatibility) |
| | - `C`: Channels (3 for RGB) |
| | - `H`: Frame height |
| | - `W`: Frame width |
| | """ |
| | with decord.bridge.use_torch(): |
| | video_reader = decord.VideoReader(uri=video_path, width=width, height=height) |
| | video_num_frames = len(video_reader) |
| | start_frame = min(skip_frames_start, video_num_frames) |
| | end_frame = max(0, video_num_frames - skip_frames_end) |
| |
|
| | if end_frame <= start_frame: |
| | indices = [start_frame] |
| | elif end_frame - start_frame <= max_num_frames: |
| | indices = list(range(start_frame, end_frame)) |
| | else: |
| | step = frame_sample_step or (end_frame - start_frame) // max_num_frames |
| | indices = list(range(start_frame, end_frame, step)) |
| |
|
| | frames = video_reader.get_batch(indices=indices) |
| | frames = frames[:max_num_frames].float() |
| |
|
| | |
| | selected_num_frames = frames.size(0) |
| | remainder = (3 + selected_num_frames) % 4 |
| | if remainder != 0: |
| | frames = frames[:-remainder] |
| | assert frames.size(0) % 4 == 1 |
| |
|
| | |
| | transform = T.Lambda(lambda x: x / 255.0 * 2.0 - 1.0) |
| | frames = torch.stack(tuple(map(transform, frames)), dim=0) |
| |
|
| | return frames.permute(0, 3, 1, 2).contiguous() |
| |
|
| |
|
| | class CogVideoXDDIMInversionOutput: |
| | inverse_latents: torch.FloatTensor |
| | recon_latents: torch.FloatTensor |
| |
|
| | def __init__(self, inverse_latents: torch.FloatTensor, recon_latents: torch.FloatTensor): |
| | self.inverse_latents = inverse_latents |
| | self.recon_latents = recon_latents |
| |
|
| |
|
| | class CogVideoXPipelineForDDIMInversion(CogVideoXPipeline): |
| | def __init__( |
| | self, |
| | tokenizer: T5Tokenizer, |
| | text_encoder: T5EncoderModel, |
| | vae: AutoencoderKLCogVideoX, |
| | transformer: CogVideoXTransformer3DModel, |
| | scheduler: CogVideoXDDIMScheduler, |
| | ): |
| | super().__init__( |
| | tokenizer=tokenizer, |
| | text_encoder=text_encoder, |
| | vae=vae, |
| | transformer=transformer, |
| | scheduler=scheduler, |
| | ) |
| | self.inverse_scheduler = DDIMInverseScheduler(**scheduler.config) |
| |
|
| | def encode_video_frames(self, video_frames: torch.FloatTensor) -> torch.FloatTensor: |
| | """ |
| | Encode video frames into latent space using Variational Autoencoder. |
| | |
| | Args: |
| | video_frames (`torch.FloatTensor`): |
| | Input frames tensor in `[F, C, H, W]` format from `get_video_frames()` |
| | |
| | Returns: |
| | `torch.FloatTensor`: Encoded latents in `[1, F, D, H_latent, W_latent]` format where: |
| | - `F`: Number of frames (same as input) |
| | - `D`: Latent channel dimension |
| | - `H_latent`: Latent space height (H // 2^vae.downscale_factor) |
| | - `W_latent`: Latent space width (W // 2^vae.downscale_factor) |
| | """ |
| | vae: AutoencoderKLCogVideoX = self.vae |
| | video_frames = video_frames.to(device=vae.device, dtype=vae.dtype) |
| | video_frames = video_frames.unsqueeze(0).permute(0, 2, 1, 3, 4) |
| | latent_dist = vae.encode(x=video_frames).latent_dist.sample().transpose(1, 2) |
| | return latent_dist * vae.config.scaling_factor |
| |
|
| | @torch.no_grad() |
| | def export_latents_to_video(self, latents: torch.FloatTensor, video_path: str, fps: int): |
| | r""" |
| | Decode latent vectors into video and export as video file. |
| | |
| | Args: |
| | latents (`torch.FloatTensor`): Encoded latents in `[B, F, D, H_latent, W_latent]` format from |
| | `encode_video_frames()` |
| | video_path (`str`): Output path for video file |
| | fps (`int`): Target frames per second for output video |
| | """ |
| | video = self.decode_latents(latents) |
| | frames = self.video_processor.postprocess_video(video=video, output_type="pil") |
| | os.makedirs(os.path.dirname(video_path), exist_ok=True) |
| | export_to_video(video_frames=frames[0], output_video_path=video_path, fps=fps) |
| |
|
| | |
| | @torch.no_grad() |
| | def sample( |
| | self, |
| | latents: torch.FloatTensor, |
| | scheduler: Union[DDIMInverseScheduler, CogVideoXDDIMScheduler], |
| | prompt: Optional[Union[str, List[str]]] = None, |
| | negative_prompt: Optional[Union[str, List[str]]] = None, |
| | num_inference_steps: int = 50, |
| | guidance_scale: float = 6, |
| | use_dynamic_cfg: bool = False, |
| | eta: float = 0.0, |
| | generator: Optional[Union[torch.Generator, List[torch.Generator]]] = None, |
| | attention_kwargs: Optional[Dict[str, Any]] = None, |
| | reference_latents: torch.FloatTensor = None, |
| | ) -> torch.FloatTensor: |
| | r""" |
| | Execute the core sampling loop for video generation/inversion using CogVideoX. |
| | |
| | Implements the full denoising trajectory recording for both DDIM inversion and |
| | generation processes. Supports dynamic classifier-free guidance and reference |
| | latent conditioning. |
| | |
| | Args: |
| | latents (`torch.FloatTensor`): |
| | Initial noise tensor of shape `[B, F, C, H, W]`. |
| | scheduler (`Union[DDIMInverseScheduler, CogVideoXDDIMScheduler]`): |
| | Scheduling strategy for diffusion process. Use: |
| | (1) `DDIMInverseScheduler` for inversion |
| | (2) `CogVideoXDDIMScheduler` for generation |
| | prompt (`Optional[Union[str, List[str]]]`): |
| | Text prompt(s) for conditional generation. Defaults to unconditional. |
| | negative_prompt (`Optional[Union[str, List[str]]]`): |
| | Negative prompt(s) for guidance. Requires `guidance_scale > 1`. |
| | num_inference_steps (`int`): |
| | Number of denoising steps. Affects quality/compute trade-off. |
| | guidance_scale (`float`): |
| | Classifier-free guidance weight. 1.0 = no guidance. |
| | use_dynamic_cfg (`bool`): |
| | Enable time-varying guidance scale (cosine schedule) |
| | eta (`float`): |
| | DDIM variance parameter (0 = deterministic process) |
| | generator (`Optional[Union[torch.Generator, List[torch.Generator]]]`): |
| | Random number generator(s) for reproducibility |
| | attention_kwargs (`Optional[Dict[str, Any]]`): |
| | Custom parameters for attention modules |
| | reference_latents (`torch.FloatTensor`): |
| | Reference latent trajectory for conditional sampling. Shape should match |
| | `[T, B, F, C, H, W]` where `T` is number of timesteps |
| | |
| | Returns: |
| | `torch.FloatTensor`: |
| | Full denoising trajectory tensor of shape `[T, B, F, C, H, W]`. |
| | """ |
| | self._guidance_scale = guidance_scale |
| | self._attention_kwargs = attention_kwargs |
| | self._interrupt = False |
| |
|
| | device = self._execution_device |
| |
|
| | |
| | |
| | |
| | do_classifier_free_guidance = guidance_scale > 1.0 |
| |
|
| | |
| | prompt_embeds, negative_prompt_embeds = self.encode_prompt( |
| | prompt, |
| | negative_prompt, |
| | do_classifier_free_guidance, |
| | device=device, |
| | ) |
| | if do_classifier_free_guidance: |
| | prompt_embeds = torch.cat([negative_prompt_embeds, prompt_embeds], dim=0) |
| | if reference_latents is not None: |
| | prompt_embeds = torch.cat([prompt_embeds] * 2, dim=0) |
| |
|
| | |
| | timesteps, num_inference_steps = retrieve_timesteps(scheduler, num_inference_steps, device) |
| | self._num_timesteps = len(timesteps) |
| |
|
| | |
| | latents = latents.to(device=device) * scheduler.init_noise_sigma |
| |
|
| | |
| | extra_step_kwargs = self.prepare_extra_step_kwargs(generator, eta) |
| | if isinstance(scheduler, DDIMInverseScheduler): |
| | extra_step_kwargs = {} |
| |
|
| | |
| | image_rotary_emb = ( |
| | self._prepare_rotary_positional_embeddings( |
| | height=latents.size(3) * self.vae_scale_factor_spatial, |
| | width=latents.size(4) * self.vae_scale_factor_spatial, |
| | num_frames=latents.size(1), |
| | device=device, |
| | ) |
| | if self.transformer.config.use_rotary_positional_embeddings |
| | else None |
| | ) |
| |
|
| | |
| | num_warmup_steps = max(len(timesteps) - num_inference_steps * scheduler.order, 0) |
| |
|
| | trajectory = torch.zeros_like(latents).unsqueeze(0).repeat(len(timesteps), 1, 1, 1, 1, 1) |
| | with self.progress_bar(total=num_inference_steps) as progress_bar: |
| | for i, t in enumerate(timesteps): |
| | if self.interrupt: |
| | continue |
| |
|
| | latent_model_input = torch.cat([latents] * 2) if do_classifier_free_guidance else latents |
| | if reference_latents is not None: |
| | reference = reference_latents[i] |
| | reference = torch.cat([reference] * 2) if do_classifier_free_guidance else reference |
| | latent_model_input = torch.cat([latent_model_input, reference], dim=0) |
| | latent_model_input = scheduler.scale_model_input(latent_model_input, t) |
| |
|
| | |
| | timestep = t.expand(latent_model_input.shape[0]) |
| |
|
| | |
| | noise_pred = self.transformer( |
| | hidden_states=latent_model_input, |
| | encoder_hidden_states=prompt_embeds, |
| | timestep=timestep, |
| | image_rotary_emb=image_rotary_emb, |
| | attention_kwargs=attention_kwargs, |
| | return_dict=False, |
| | )[0] |
| | noise_pred = noise_pred.float() |
| |
|
| | if reference_latents is not None: |
| | noise_pred, _ = noise_pred.chunk(2) |
| |
|
| | |
| | if use_dynamic_cfg: |
| | self._guidance_scale = 1 + guidance_scale * ( |
| | (1 - math.cos(math.pi * ((num_inference_steps - t.item()) / num_inference_steps) ** 5.0)) / 2 |
| | ) |
| | if do_classifier_free_guidance: |
| | noise_pred_uncond, noise_pred_text = noise_pred.chunk(2) |
| | noise_pred = noise_pred_uncond + self.guidance_scale * (noise_pred_text - noise_pred_uncond) |
| |
|
| | |
| | latents = scheduler.step(noise_pred, t, latents, **extra_step_kwargs, return_dict=False)[0] |
| | latents = latents.to(prompt_embeds.dtype) |
| | trajectory[i] = latents |
| |
|
| | if i == len(timesteps) - 1 or ((i + 1) > num_warmup_steps and (i + 1) % scheduler.order == 0): |
| | progress_bar.update() |
| |
|
| | |
| | self.maybe_free_model_hooks() |
| |
|
| | return trajectory |
| |
|
| | @torch.no_grad() |
| | def __call__( |
| | self, |
| | prompt: str, |
| | video_path: str, |
| | guidance_scale: float, |
| | num_inference_steps: int, |
| | skip_frames_start: int, |
| | skip_frames_end: int, |
| | frame_sample_step: Optional[int], |
| | max_num_frames: int, |
| | width: int, |
| | height: int, |
| | seed: int, |
| | ): |
| | """ |
| | Performs DDIM inversion on a video to reconstruct it with a new prompt. |
| | |
| | Args: |
| | prompt (`str`): The text prompt to guide the reconstruction. |
| | video_path (`str`): Path to the input video file. |
| | guidance_scale (`float`): Scale for classifier-free guidance. |
| | num_inference_steps (`int`): Number of denoising steps. |
| | skip_frames_start (`int`): Number of frames to skip from the beginning of the video. |
| | skip_frames_end (`int`): Number of frames to skip from the end of the video. |
| | frame_sample_step (`Optional[int]`): Step size for sampling frames. If None, all frames are used. |
| | max_num_frames (`int`): Maximum number of frames to process. |
| | width (`int`): Width of the output video frames. |
| | height (`int`): Height of the output video frames. |
| | seed (`int`): Random seed for reproducibility. |
| | |
| | Returns: |
| | `CogVideoXDDIMInversionOutput`: Contains the inverse latents and reconstructed latents. |
| | """ |
| | if not self.transformer.config.use_rotary_positional_embeddings: |
| | raise NotImplementedError("This script supports CogVideoX 5B model only.") |
| | video_frames = get_video_frames( |
| | video_path=video_path, |
| | width=width, |
| | height=height, |
| | skip_frames_start=skip_frames_start, |
| | skip_frames_end=skip_frames_end, |
| | max_num_frames=max_num_frames, |
| | frame_sample_step=frame_sample_step, |
| | ).to(device=self.device) |
| | video_latents = self.encode_video_frames(video_frames=video_frames) |
| | inverse_latents = self.sample( |
| | latents=video_latents, |
| | scheduler=self.inverse_scheduler, |
| | prompt="", |
| | num_inference_steps=num_inference_steps, |
| | guidance_scale=guidance_scale, |
| | generator=torch.Generator(device=self.device).manual_seed(seed), |
| | ) |
| | with OverrideAttnProcessors(transformer=self.transformer): |
| | recon_latents = self.sample( |
| | latents=torch.randn_like(video_latents), |
| | scheduler=self.scheduler, |
| | prompt=prompt, |
| | num_inference_steps=num_inference_steps, |
| | guidance_scale=guidance_scale, |
| | generator=torch.Generator(device=self.device).manual_seed(seed), |
| | reference_latents=reversed(inverse_latents), |
| | ) |
| | return CogVideoXDDIMInversionOutput( |
| | inverse_latents=inverse_latents, |
| | recon_latents=recon_latents, |
| | ) |
| |
|
| |
|
| | if __name__ == "__main__": |
| | arguments = get_args() |
| | pipeline = CogVideoXPipelineForDDIMInversion.from_pretrained( |
| | arguments.pop("model_path"), |
| | torch_dtype=arguments.pop("dtype"), |
| | ).to(device=arguments.pop("device")) |
| |
|
| | output_path = arguments.pop("output_path") |
| | fps = arguments.pop("fps") |
| | inverse_video_path = os.path.join(output_path, f"{arguments.get('video_path')}_inversion.mp4") |
| | recon_video_path = os.path.join(output_path, f"{arguments.get('video_path')}_reconstruction.mp4") |
| |
|
| | |
| | output = pipeline(**arguments) |
| | pipeline.export_latents_to_video(output.inverse_latents[-1], inverse_video_path, fps) |
| | pipeline.export_latents_to_video(output.recon_latents[-1], recon_video_path, fps) |
| |
|