video_utils.py

### copied from  https://github.com/NUS-HPC-AI-Lab/OpenDiT/blob/master/opendit/utils/data_utils.py#L99

import csv
import numbers
import random

import numpy as np
import torch
import torchvision
import torchvision.transforms as transforms
from torchvision.datasets.folder import IMG_EXTENSIONS, pil_loader
from PIL import Image


def center_crop_arr(pil_image, image_size):
    """
    Center cropping implementation from ADM.
    https://github.com/openai/guided-diffusion/blob/8fb3ad9197f16bbc40620447b2742e13458d2831/guided_diffusion/image_datasets.py#L126
    """
    while min(*pil_image.size) >= 2 * image_size:
        pil_image = pil_image.resize(
            tuple(x // 2 for x in pil_image.size), resample=Image.BOX
        )

    scale = image_size / min(*pil_image.size)
    pil_image = pil_image.resize(
        tuple(round(x * scale) for x in pil_image.size), resample=Image.BICUBIC
    )

    arr = np.array(pil_image)
    crop_y = (arr.shape[0] - image_size) // 2
    crop_x = (arr.shape[1] - image_size) // 2
    return Image.fromarray(
        arr[crop_y : crop_y + image_size, crop_x : crop_x + image_size]
    )


def _is_tensor_video_clip(clip):
    if not torch.is_tensor(clip):
        raise TypeError("clip should be Tensor. Got %s" % type(clip))

    if not clip.ndimension() == 4:
        raise ValueError("clip should be 4D. Got %dD" % clip.dim())

    return True


def crop(clip, i, j, h, w):
    """
    Args:
        clip (torch.tensor): Video clip to be cropped. Size is (T, C, H, W)
    """
    if len(clip.size()) != 4:
        raise ValueError("clip should be a 4D tensor")
    return clip[..., i : i + h, j : j + w]


def resize(clip, target_size, interpolation_mode):
    if len(target_size) != 2:
        raise ValueError(
            f"target size should be tuple (height, width), instead got {target_size}"
        )
    return torch.nn.functional.interpolate(
        clip, size=target_size, mode=interpolation_mode, align_corners=False
    )


def resize_scale(clip, target_size, interpolation_mode):
    if len(target_size) != 2:
        raise ValueError(
            f"target size should be tuple (height, width), instead got {target_size}"
        )
    H, W = clip.size(-2), clip.size(-1)
    scale_ = target_size[0] / min(H, W)
    return torch.nn.functional.interpolate(
        clip, scale_factor=scale_, mode=interpolation_mode, align_corners=False
    )


def resized_crop(clip, i, j, h, w, size, interpolation_mode="bilinear"):
    """
    Do spatial cropping and resizing to the video clip
    Args:
        clip (torch.tensor): Video clip to be cropped. Size is (T, C, H, W)
        i (int): i in (i,j) i.e coordinates of the upper left corner.
        j (int): j in (i,j) i.e coordinates of the upper left corner.
        h (int): Height of the cropped region.
        w (int): Width of the cropped region.
        size (tuple(int, int)): height and width of resized clip
    Returns:
        clip (torch.tensor): Resized and cropped clip. Size is (T, C, H, W)
    """
    if not _is_tensor_video_clip(clip):
        raise ValueError("clip should be a 4D torch.tensor")
    clip = crop(clip, i, j, h, w)
    clip = resize(clip, size, interpolation_mode)
    return clip


def center_crop(clip, crop_size):
    if not _is_tensor_video_clip(clip):
        raise ValueError("clip should be a 4D torch.tensor")
    h, w = clip.size(-2), clip.size(-1)
    th, tw = crop_size
    if h < th or w < tw:
        raise ValueError("height and width must be no smaller than crop_size")

    i = int(round((h - th) / 2.0))
    j = int(round((w - tw) / 2.0))
    return crop(clip, i, j, th, tw)


def center_crop_using_short_edge(clip):
    if not _is_tensor_video_clip(clip):
        raise ValueError("clip should be a 4D torch.tensor")
    h, w = clip.size(-2), clip.size(-1)
    if h < w:
        th, tw = h, h
        i = 0
        j = int(round((w - tw) / 2.0))
    else:
        th, tw = w, w
        i = int(round((h - th) / 2.0))
        j = 0
    return crop(clip, i, j, th, tw)


def random_shift_crop(clip):
    """
    Slide along the long edge, with the short edge as crop size
    """
    if not _is_tensor_video_clip(clip):
        raise ValueError("clip should be a 4D torch.tensor")
    h, w = clip.size(-2), clip.size(-1)

    if h <= w:
        short_edge = h
    else:
        short_edge = w

    th, tw = short_edge, short_edge

    i = torch.randint(0, h - th + 1, size=(1,)).item()
    j = torch.randint(0, w - tw + 1, size=(1,)).item()
    return crop(clip, i, j, th, tw)


def to_tensor(clip):
    """
    Convert tensor data type from uint8 to float, divide value by 255.0 and
    permute the dimensions of clip tensor
    Args:
        clip (torch.tensor, dtype=torch.uint8): Size is (T, C, H, W)
    Return:
        clip (torch.tensor, dtype=torch.float): Size is (T, C, H, W)
    """
    _is_tensor_video_clip(clip)
    if not clip.dtype == torch.uint8:
        raise TypeError(
            "clip tensor should have data type uint8. Got %s" % str(clip.dtype)
        )
    # return clip.float().permute(3, 0, 1, 2) / 255.0
    return clip.float() / 255.0


def normalize(clip, mean, std, inplace=False):
    """
    Args:
        clip (torch.tensor): Video clip to be normalized. Size is (T, C, H, W)
        mean (tuple): pixel RGB mean. Size is (3)
        std (tuple): pixel standard deviation. Size is (3)
    Returns:
        normalized clip (torch.tensor): Size is (T, C, H, W)
    """
    if not _is_tensor_video_clip(clip):
        raise ValueError("clip should be a 4D torch.tensor")
    if not inplace:
        clip = clip.clone()
    mean = torch.as_tensor(mean, dtype=clip.dtype, device=clip.device)
    # print(mean)
    std = torch.as_tensor(std, dtype=clip.dtype, device=clip.device)
    clip.sub_(mean[:, None, None, None]).div_(std[:, None, None, None])
    return clip


def hflip(clip):
    """
    Args:
        clip (torch.tensor): Video clip to be normalized. Size is (T, C, H, W)
    Returns:
        flipped clip (torch.tensor): Size is (T, C, H, W)
    """
    if not _is_tensor_video_clip(clip):
        raise ValueError("clip should be a 4D torch.tensor")
    return clip.flip(-1)


class RandomCropVideo:
    def __init__(self, size):
        if isinstance(size, numbers.Number):
            self.size = (int(size), int(size))
        else:
            self.size = size

    def __call__(self, clip):
        """
        Args:
            clip (torch.tensor): Video clip to be cropped. Size is (T, C, H, W)
        Returns:
            torch.tensor: randomly cropped video clip.
                size is (T, C, OH, OW)
        """
        i, j, h, w = self.get_params(clip)
        return crop(clip, i, j, h, w)

    def get_params(self, clip):
        h, w = clip.shape[-2:]
        th, tw = self.size

        if h < th or w < tw:
            raise ValueError(
                f"Required crop size {(th, tw)} is larger than input image size {(h, w)}"
            )

        if w == tw and h == th:
            return 0, 0, h, w

        i = torch.randint(0, h - th + 1, size=(1,)).item()
        j = torch.randint(0, w - tw + 1, size=(1,)).item()

        return i, j, th, tw

    def __repr__(self) -> str:
        return f"{self.__class__.__name__}(size={self.size})"


class CenterCropResizeVideo:
    """
    First use the short side for cropping length,
    center crop video, then resize to the specified size
    """

    def __init__(
        self,
        size,
        interpolation_mode="bilinear",
    ):
        if isinstance(size, tuple):
            if len(size) != 2:
                raise ValueError(
                    f"size should be tuple (height, width), instead got {size}"
                )
            self.size = size
        else:
            self.size = (size, size)

        self.interpolation_mode = interpolation_mode

    def __call__(self, clip):
        """
        Args:
            clip (torch.tensor): Video clip to be cropped. Size is (T, C, H, W)
        Returns:
            torch.tensor: scale resized / center cropped video clip.
                size is (T, C, crop_size, crop_size)
        """
        clip_center_crop = center_crop_using_short_edge(clip)
        clip_center_crop_resize = resize(
            clip_center_crop,
            target_size=self.size,
            interpolation_mode=self.interpolation_mode,
        )
        return clip_center_crop_resize

    def __repr__(self) -> str:
        return f"{self.__class__.__name__}(size={self.size}, interpolation_mode={self.interpolation_mode}"


class UCFCenterCropVideo:
    """
    First scale to the specified size in equal proportion to the short edge,
    then center cropping
    """

    def __init__(
        self,
        size,
        interpolation_mode="bilinear",
    ):
        if isinstance(size, tuple):
            if len(size) != 2:
                raise ValueError(
                    f"size should be tuple (height, width), instead got {size}"
                )
            self.size = size
        else:
            self.size = (size, size)

        self.interpolation_mode = interpolation_mode

    def __call__(self, clip):
        """
        Args:
            clip (torch.tensor): Video clip to be cropped. Size is (T, C, H, W)
        Returns:
            torch.tensor: scale resized / center cropped video clip.
                size is (T, C, crop_size, crop_size)
        """
        clip_resize = resize_scale(
            clip=clip, target_size=self.size, interpolation_mode=self.interpolation_mode
        )
        clip_center_crop = center_crop(clip_resize, self.size)
        return clip_center_crop

    def __repr__(self) -> str:
        return f"{self.__class__.__name__}(size={self.size}, interpolation_mode={self.interpolation_mode}"


class KineticsRandomCropResizeVideo:
    """
    Slide along the long edge, with the short edge as crop size. And resie to the desired size.
    """

    def __init__(
        self,
        size,
        interpolation_mode="bilinear",
    ):
        if isinstance(size, tuple):
            if len(size) != 2:
                raise ValueError(
                    f"size should be tuple (height, width), instead got {size}"
                )
            self.size = size
        else:
            self.size = (size, size)

        self.interpolation_mode = interpolation_mode

    def __call__(self, clip):
        clip_random_crop = random_shift_crop(clip)
        clip_resize = resize(clip_random_crop, self.size, self.interpolation_mode)
        return clip_resize


class CenterCropVideo:
    def __init__(
        self,
        size,
        interpolation_mode="bilinear",
    ):
        if isinstance(size, tuple):
            if len(size) != 2:
                raise ValueError(
                    f"size should be tuple (height, width), instead got {size}"
                )
            self.size = size
        else:
            self.size = (size, size)

        self.interpolation_mode = interpolation_mode

    def __call__(self, clip):
        """
        Args:
            clip (torch.tensor): Video clip to be cropped. Size is (T, C, H, W)
        Returns:
            torch.tensor: center cropped video clip.
                size is (T, C, crop_size, crop_size)
        """
        clip_center_crop = center_crop(clip, self.size)
        return clip_center_crop

    def __repr__(self) -> str:
        return f"{self.__class__.__name__}(size={self.size}, interpolation_mode={self.interpolation_mode}"


class NormalizeVideo:
    """
    Normalize the video clip by mean subtraction and division by standard deviation
    Args:
        mean (3-tuple): pixel RGB mean
        std (3-tuple): pixel RGB standard deviation
        inplace (boolean): whether do in-place normalization
    """

    def __init__(self, mean, std, inplace=False):
        self.mean = mean
        self.std = std
        self.inplace = inplace

    def __call__(self, clip):
        """
        Args:
            clip (torch.tensor): video clip must be normalized. Size is (C, T, H, W)
        """
        return normalize(clip, self.mean, self.std, self.inplace)

    def __repr__(self) -> str:
        return f"{self.__class__.__name__}(mean={self.mean}, std={self.std}, inplace={self.inplace})"


class ToTensorVideo:
    """
    Convert tensor data type from uint8 to float, divide value by 255.0 and
    permute the dimensions of clip tensor
    """

    def __init__(self):
        pass

    def __call__(self, clip):
        """
        Args:
            clip (torch.tensor, dtype=torch.uint8): Size is (T, C, H, W)
        Return:
            clip (torch.tensor, dtype=torch.float): Size is (T, C, H, W)
        """
        return to_tensor(clip)

    def __repr__(self) -> str:
        return self.__class__.__name__


class RandomHorizontalFlipVideo:
    """
    Flip the video clip along the horizontal direction with a given probability
    Args:
        p (float): probability of the clip being flipped. Default value is 0.5
    """

    def __init__(self, p=0.5):
        self.p = p

    def __call__(self, clip):
        """
        Args:
            clip (torch.tensor): Size is (T, C, H, W)
        Return:
            clip (torch.tensor): Size is (T, C, H, W)
        """
        if random.random() < self.p:
            clip = hflip(clip)
        return clip

    def __repr__(self) -> str:
        return f"{self.__class__.__name__}(p={self.p})"


#  ------------------------------------------------------------
#  ---------------------  Sampling  ---------------------------
#  ------------------------------------------------------------
class TemporalRandomCrop(object):
    """Temporally crop the given frame indices at a random location.

    Args:
            size (int): Desired length of frames will be seen in the model.
    """

    def __init__(self, size):
        self.size = size

    def __call__(self, total_frames):
        rand_end = max(0, total_frames - self.size - 1)
        begin_index = random.randint(0, rand_end)
        end_index = min(begin_index + self.size, total_frames)
        return begin_index, end_index


class DatasetFromCSV(torch.utils.data.Dataset):
    """load video according to the csv file.

    Args:
        target_video_len (int): the number of video frames will be load.
        align_transform (callable): Align different videos in a specified size.
        temporal_sample (callable): Sample the target length of a video.
    """

    def __init__(
        self,
        csv_path,
        num_frames=16,
        frame_interval=1,
        transform=None,
    ):
        self.csv_path = csv_path
        with open(csv_path, "r") as f:
            reader = csv.reader(f)
            self.samples = list(reader)

        # TODO, generate id_name mapping

        ext = self.samples[0][0].split(".")[-1]
        if ext.lower() in ["mp4", "avi", "mov", "mkv"]:
            self.is_video = True
        else:
            assert f".{ext.lower()}" in IMG_EXTENSIONS
            self.is_video = False

        self.transform = transform

        self.num_frames = num_frames
        self.frame_interval = frame_interval
        self.temporal_sample = TemporalRandomCrop(num_frames * frame_interval)
        from diffusers import StableDiffusionPipeline

        image_model_id = "runwayml/stable-diffusion-v1-5"
        pipe = StableDiffusionPipeline.from_pretrained(
            image_model_id, local_files_only=True
        )
        self.vae = pipe.vae.to("cuda")

    def __getitem__(self, index):
        path, text, _id = self.samples[index]

        if self.is_video:
            vframes, aframes, info = torchvision.io.read_video(
                filename=path, pts_unit="sec", output_format="TCHW"
            )
            total_frames = len(vframes)

            # Sampling video frames
            start_frame_ind, end_frame_ind = self.temporal_sample(total_frames)
            assert end_frame_ind - start_frame_ind >= self.num_frames
            frame_indice = np.linspace(
                start_frame_ind, end_frame_ind - 1, self.num_frames, dtype=int
            )

            video = vframes[frame_indice]
            video = self.transform(video)  # T C H W
            with torch.no_grad():
                latents256 = []
                for _frame in video:
                    assert _frame.max() <= 1.001 and _frame.min() >= -1.01
                    latents256_j = self.vae.encode(
                        _frame.unsqueeze(0).to("cuda")
                    ).latent_dist.sample()[0]
                    latents256_j = latents256_j.detach().cpu().numpy()
                    latents256.append(latents256_j)
                latents256 = np.array(latents256)

        else:
            raise NotImplementedError
            image = pil_loader(path)
            image = self.transform(image)
            video = image.unsqueeze(0).repeat(self.num_frames, 1, 1, 1)

        # TCHW -> CTHW
        # video = video.permute(1, 0, 2, 3)

        return {
            "video": video,
            "text": text,
            "cls_id": _id,
            "frame_feature256": latents256,
        }

    def __len__(self):
        return len(self.samples)


def get_transforms_video(resolution=256):
    transform_video = transforms.Compose(
        [
            ToTensorVideo(),  # TCHW
            RandomHorizontalFlipVideo(),
            UCFCenterCropVideo(resolution),
            transforms.Normalize(
                mean=[0.5, 0.5, 0.5], std=[0.5, 0.5, 0.5], inplace=True
            ),
        ]
    )
    return transform_video


def get_transforms_image(image_size=256):
    transform = transforms.Compose(
        [
            transforms.Lambda(lambda pil_image: center_crop_arr(pil_image, image_size)),
            transforms.RandomHorizontalFlip(),
            transforms.ToTensor(),
            transforms.Normalize(
                mean=[0.5, 0.5, 0.5], std=[0.5, 0.5, 0.5], inplace=True
            ),
        ]
    )
    return transform