ComfyUI/comfy/ldm/lightricks/symmetric_patchifier.py
2026-01-04 18:31:23 -05:00

191 lines
7.2 KiB
Python

from abc import ABC, abstractmethod
from typing import Tuple
import torch
from einops import rearrange
from torch import Tensor
def latent_to_pixel_coords(
latent_coords: Tensor, scale_factors: Tuple[int, int, int], causal_fix: bool = False
) -> Tensor:
"""
Converts latent coordinates to pixel coordinates by scaling them according to the VAE's
configuration.
Args:
latent_coords (Tensor): A tensor of shape [batch_size, 3, num_latents]
containing the latent corner coordinates of each token.
scale_factors (Tuple[int, int, int]): The scale factors of the VAE's latent space.
causal_fix (bool): Whether to take into account the different temporal scale
of the first frame. Default = False for backwards compatibility.
Returns:
Tensor: A tensor of pixel coordinates corresponding to the input latent coordinates.
"""
shape = [1] * latent_coords.ndim
shape[1] = -1
pixel_coords = (
latent_coords
* torch.tensor(scale_factors, device=latent_coords.device).view(*shape)
)
if causal_fix:
# Fix temporal scale for first frame to 1 due to causality
pixel_coords[:, 0, ...] = (pixel_coords[:, 0, ...] + 1 - scale_factors[0]).clamp(min=0)
return pixel_coords
class Patchifier(ABC):
def __init__(self, patch_size: int, start_end: bool=False):
super().__init__()
self._patch_size = (1, patch_size, patch_size)
self.start_end = start_end
@abstractmethod
def patchify(
self, latents: Tensor, frame_rates: Tensor, scale_grid: bool
) -> Tuple[Tensor, Tensor]:
pass
@abstractmethod
def unpatchify(
self,
latents: Tensor,
output_height: int,
output_width: int,
output_num_frames: int,
out_channels: int,
) -> Tuple[Tensor, Tensor]:
pass
@property
def patch_size(self):
return self._patch_size
def get_latent_coords(
self, latent_num_frames, latent_height, latent_width, batch_size, device
):
"""
Return a tensor of shape [batch_size, 3, num_patches] containing the
top-left corner latent coordinates of each latent patch.
The tensor is repeated for each batch element.
"""
latent_sample_coords = torch.meshgrid(
torch.arange(0, latent_num_frames, self._patch_size[0], device=device),
torch.arange(0, latent_height, self._patch_size[1], device=device),
torch.arange(0, latent_width, self._patch_size[2], device=device),
indexing="ij",
)
latent_sample_coords_start = torch.stack(latent_sample_coords, dim=0)
delta = torch.tensor(self._patch_size, device=latent_sample_coords_start.device, dtype=latent_sample_coords_start.dtype)[:, None, None, None]
latent_sample_coords_end = latent_sample_coords_start + delta
latent_sample_coords_start = latent_sample_coords_start.unsqueeze(0).repeat(batch_size, 1, 1, 1, 1)
latent_sample_coords_start = rearrange(
latent_sample_coords_start, "b c f h w -> b c (f h w)", b=batch_size
)
if self.start_end:
latent_sample_coords_end = latent_sample_coords_end.unsqueeze(0).repeat(batch_size, 1, 1, 1, 1)
latent_sample_coords_end = rearrange(
latent_sample_coords_end, "b c f h w -> b c (f h w)", b=batch_size
)
latent_coords = torch.stack((latent_sample_coords_start, latent_sample_coords_end), dim=-1)
else:
latent_coords = latent_sample_coords_start
return latent_coords
class SymmetricPatchifier(Patchifier):
def patchify(
self,
latents: Tensor,
) -> Tuple[Tensor, Tensor]:
b, _, f, h, w = latents.shape
latent_coords = self.get_latent_coords(f, h, w, b, latents.device)
latents = rearrange(
latents,
"b c (f p1) (h p2) (w p3) -> b (f h w) (c p1 p2 p3)",
p1=self._patch_size[0],
p2=self._patch_size[1],
p3=self._patch_size[2],
)
return latents, latent_coords
def unpatchify(
self,
latents: Tensor,
output_height: int,
output_width: int,
output_num_frames: int,
out_channels: int,
) -> Tuple[Tensor, Tensor]:
output_height = output_height // self._patch_size[1]
output_width = output_width // self._patch_size[2]
latents = rearrange(
latents,
"b (f h w) (c p q) -> b c f (h p) (w q) ",
f=output_num_frames,
h=output_height,
w=output_width,
p=self._patch_size[1],
q=self._patch_size[2],
)
return latents
class AudioPatchifier(Patchifier):
def __init__(self, patch_size: int,
sample_rate=16000,
hop_length=160,
audio_latent_downsample_factor=4,
is_causal=True,
start_end=False,
shift = 0
):
super().__init__(patch_size, start_end=start_end)
self.hop_length = hop_length
self.sample_rate = sample_rate
self.audio_latent_downsample_factor = audio_latent_downsample_factor
self.is_causal = is_causal
self.shift = shift
def copy_with_shift(self, shift):
return AudioPatchifier(
self.patch_size, self.sample_rate, self.hop_length, self.audio_latent_downsample_factor,
self.is_causal, self.start_end, shift
)
def _get_audio_latent_time_in_sec(self, start_latent, end_latent: int, dtype: torch.dtype, device=torch.device):
audio_latent_frame = torch.arange(start_latent, end_latent, dtype=dtype, device=device)
audio_mel_frame = audio_latent_frame * self.audio_latent_downsample_factor
if self.is_causal:
audio_mel_frame = (audio_mel_frame + 1 - self.audio_latent_downsample_factor).clip(min=0)
return audio_mel_frame * self.hop_length / self.sample_rate
def patchify(self, audio_latents: torch.Tensor) -> Tuple[torch.Tensor, torch.Tensor]:
# audio_latents: (batch, channels, time, freq)
b, _, t, _ = audio_latents.shape
audio_latents = rearrange(
audio_latents,
"b c t f -> b t (c f)",
)
audio_latents_start_timings = self._get_audio_latent_time_in_sec(self.shift, t + self.shift, torch.float32, audio_latents.device)
audio_latents_start_timings = audio_latents_start_timings.unsqueeze(0).expand(b, -1).unsqueeze(1)
if self.start_end:
audio_latents_end_timings = self._get_audio_latent_time_in_sec(self.shift + 1, t + self.shift + 1, torch.float32, audio_latents.device)
audio_latents_end_timings = audio_latents_end_timings.unsqueeze(0).expand(b, -1).unsqueeze(1)
audio_latents_timings = torch.stack([audio_latents_start_timings, audio_latents_end_timings], dim=-1)
else:
audio_latents_timings = audio_latents_start_timings
return audio_latents, audio_latents_timings
def unpatchify(self, audio_latents: torch.Tensor, channels: int, freq: int) -> torch.Tensor:
# audio_latents: (batch, time, freq * channels)
audio_latents = rearrange(
audio_latents, "b t (c f) -> b c t f", c=channels, f=freq
)
return audio_latents