# Video processor function used in the original VIdeoPrism repo.

import mediapy
import numpy as np
def read_and_preprocess_video(
    filename: str, target_num_frames: int, target_frame_size: tuple[int, int]
):
    """Reads and preprocesses a video."""

    frames = mediapy.read_video(filename)

    # Sample to target number of frames.
    frame_indices = np.linspace(0, len(frames), num=target_num_frames, endpoint=False, dtype=np.int32)
    frames = np.array([frames[i] for i in frame_indices])

    # Resize to target size.
    original_height, original_width = frames.shape[-3:-1]
    target_height, target_width = target_frame_size
    assert original_height * target_width == original_width * target_height, (
        "Currently does not support aspect ratio mismatch."
    )
    frames = mediapy.resize_video(frames, shape=target_frame_size)

    # Normalize pixel values to [0.0, 1.0].
    frames = mediapy.to_float01(frames)

    return frames