fix: CogVideox train dataset _preprocess_data crop video (#9574)

* Removed int8 to float32 conversion (`* 2.0 - 1.0`) from `train_transforms` as it caused image overexposure.

Added `_resize_for_rectangle_crop` function to enable video cropping functionality. The cropping mode can be configured via `video_reshape_mode`, supporting options: ['center', 'random', 'none'].

* The number 127.5 may experience precision loss during division operations.

* wandb request pil image Type

* Resizing bug

* del jupyter

* make style

* Update examples/cogvideo/README.md

* make style

---------

Co-authored-by: --unset <--unset>
Co-authored-by: Aryan <aryan@huggingface.co>

examples/cogvideo/README.md

@@ -180,6 +180,7 @@ Note that setting the `<ID_TOKEN>` is not necessary. From some limited experimen
 
 > [!TIP]
 > You can pass `--use_8bit_adam` to reduce the memory requirements of training.
+> You can pass `--video_reshape_mode` video cropping functionality, supporting options: ['center', 'random', 'none']. See [this](https://gist.github.com/glide-the/7658dbfd5f555be0a1a687a4139dba40) notebook for examples.
 
 > [!IMPORTANT]
 > The following settings have been tested at the time of adding CogVideoX LoRA training support:

examples/cogvideo/train_cogvideox_lora.py

@@ -21,7 +21,9 @@ import shutil
 from pathlib import Path
 from typing import List, Optional, Tuple, Union
 
+import numpy as np
 import torch
+import torchvision.transforms as TT
 import transformers
 from accelerate import Accelerator
 from accelerate.logging import get_logger
@@ -29,12 +31,14 @@ from accelerate.utils import DistributedDataParallelKwargs, ProjectConfiguration
 from huggingface_hub import create_repo, upload_folder
 from peft import LoraConfig, get_peft_model_state_dict, set_peft_model_state_dict
 from torch.utils.data import DataLoader, Dataset
-from torchvision import transforms
+from torchvision.transforms import InterpolationMode
+from torchvision.transforms.functional import resize
 from tqdm.auto import tqdm
 from transformers import AutoTokenizer, T5EncoderModel, T5Tokenizer
 
 import diffusers
 from diffusers import AutoencoderKLCogVideoX, CogVideoXDPMScheduler, CogVideoXPipeline, CogVideoXTransformer3DModel
+from diffusers.image_processor import VaeImageProcessor
 from diffusers.models.embeddings import get_3d_rotary_pos_embed
 from diffusers.optimization import get_scheduler
 from diffusers.pipelines.cogvideo.pipeline_cogvideox import get_resize_crop_region_for_grid
@@ -214,6 +218,12 @@ def get_args():
         default=720,
         help="All input videos are resized to this width.",
     )
+    parser.add_argument(
+        "--video_reshape_mode",
+        type=str,
+        default="center",
+        help="All input videos are reshaped to this mode. Choose between ['center', 'random', 'none']",
+    )
     parser.add_argument("--fps", type=int, default=8, help="All input videos will be used at this FPS.")
     parser.add_argument(
         "--max_num_frames", type=int, default=49, help="All input videos will be truncated to these many frames."
@@ -413,6 +423,7 @@ class VideoDataset(Dataset):
         video_column: str = "video",
         height: int = 480,
         width: int = 720,
+        video_reshape_mode: str = "center",
         fps: int = 8,
         max_num_frames: int = 49,
         skip_frames_start: int = 0,
@@ -429,6 +440,7 @@ class VideoDataset(Dataset):
         self.video_column = video_column
         self.height = height
         self.width = width
+        self.video_reshape_mode = video_reshape_mode
         self.fps = fps
         self.max_num_frames = max_num_frames
         self.skip_frames_start = skip_frames_start
@@ -532,6 +544,38 @@ class VideoDataset(Dataset):
 
         return instance_prompts, instance_videos
 
+    def _resize_for_rectangle_crop(self, arr):
+        image_size = self.height, self.width
+        reshape_mode = self.video_reshape_mode
+        if arr.shape[3] / arr.shape[2] > image_size[1] / image_size[0]:
+            arr = resize(
+                arr,
+                size=[image_size[0], int(arr.shape[3] * image_size[0] / arr.shape[2])],
+                interpolation=InterpolationMode.BICUBIC,
+            )
+        else:
+            arr = resize(
+                arr,
+                size=[int(arr.shape[2] * image_size[1] / arr.shape[3]), image_size[1]],
+                interpolation=InterpolationMode.BICUBIC,
+            )
+
+        h, w = arr.shape[2], arr.shape[3]
+        arr = arr.squeeze(0)
+
+        delta_h = h - image_size[0]
+        delta_w = w - image_size[1]
+
+        if reshape_mode == "random" or reshape_mode == "none":
+            top = np.random.randint(0, delta_h + 1)
+            left = np.random.randint(0, delta_w + 1)
+        elif reshape_mode == "center":
+            top, left = delta_h // 2, delta_w // 2
+        else:
+            raise NotImplementedError
+        arr = TT.functional.crop(arr, top=top, left=left, height=image_size[0], width=image_size[1])
+        return arr
+
     def _preprocess_data(self):
         try:
             import decord
@@ -542,15 +586,14 @@ class VideoDataset(Dataset):
 
         decord.bridge.set_bridge("torch")
 
-        videos = []
-        train_transforms = transforms.Compose(
-            [
-                transforms.Lambda(lambda x: x / 255.0 * 2.0 - 1.0),
-            ]
+        progress_dataset_bar = tqdm(
+            range(0, len(self.instance_video_paths)),
+            desc="Loading progress resize and crop videos",
         )
+        videos = []
 
         for filename in self.instance_video_paths:
-            video_reader = decord.VideoReader(uri=filename.as_posix(), width=self.width, height=self.height)
+            video_reader = decord.VideoReader(uri=filename.as_posix())
             video_num_frames = len(video_reader)
 
             start_frame = min(self.skip_frames_start, video_num_frames)
@@ -576,10 +619,16 @@ class VideoDataset(Dataset):
             assert (selected_num_frames - 1) % 4 == 0
 
             # Training transforms
-            frames = frames.float()
-            frames = torch.stack([train_transforms(frame) for frame in frames], dim=0)
-            videos.append(frames.permute(0, 3, 1, 2).contiguous())  # [F, C, H, W]
+            frames = (frames - 127.5) / 127.5
+            frames = frames.permute(0, 3, 1, 2)  # [F, C, H, W]
+            progress_dataset_bar.set_description(
+                f"Loading progress Resizing video from {frames.shape[2]}x{frames.shape[3]} to {self.height}x{self.width}"
+            )
+            frames = self._resize_for_rectangle_crop(frames)
+            videos.append(frames.contiguous())  # [F, C, H, W]
+            progress_dataset_bar.update(1)
 
+        progress_dataset_bar.close()
         return videos
 
 
@@ -694,8 +743,13 @@ def log_validation(
 
     videos = []
     for _ in range(args.num_validation_videos):
-        video = pipe(**pipeline_args, generator=generator, output_type="np").frames[0]
-        videos.append(video)
+        pt_images = pipe(**pipeline_args, generator=generator, output_type="pt").frames[0]
+        pt_images = torch.stack([pt_images[i] for i in range(pt_images.shape[0])])
+
+        image_np = VaeImageProcessor.pt_to_numpy(pt_images)
+        image_pil = VaeImageProcessor.numpy_to_pil(image_np)
+
+        videos.append(image_pil)
 
     for tracker in accelerator.trackers:
         phase_name = "test" if is_final_validation else "validation"
@@ -1171,6 +1225,7 @@ def main(args):
         video_column=args.video_column,
         height=args.height,
         width=args.width,
+        video_reshape_mode=args.video_reshape_mode,
         fps=args.fps,
         max_num_frames=args.max_num_frames,
         skip_frames_start=args.skip_frames_start,
@@ -1179,13 +1234,21 @@ def main(args):
         id_token=args.id_token,
     )
 
-    def encode_video(video):
+    def encode_video(video, bar):
+        bar.update(1)
         video = video.to(accelerator.device, dtype=vae.dtype).unsqueeze(0)
         video = video.permute(0, 2, 1, 3, 4)  # [B, C, F, H, W]
         latent_dist = vae.encode(video).latent_dist
         return latent_dist
 
-    train_dataset.instance_videos = [encode_video(video) for video in train_dataset.instance_videos]
+    progress_encode_bar = tqdm(
+        range(0, len(train_dataset.instance_videos)),
+        desc="Loading Encode videos",
+    )
+    train_dataset.instance_videos = [
+        encode_video(video, progress_encode_bar) for video in train_dataset.instance_videos
+    ]
+    progress_encode_bar.close()
 
     def collate_fn(examples):
         videos = [example["instance_video"].sample() * vae.config.scaling_factor for example in examples]