PadIfNeeded

Description

Pads the sides of an image if the image dimensions are less than the specified minimum dimensions.
    If the `pad_height_divisor` or `pad_width_divisor` is specified, the function additionally ensures
    that the image dimensions are divisible by these values.

    Args:
        min_height (int | None): Minimum desired height of the image. Ensures image height is at least this value.
            If not specified, pad_height_divisor must be provided.
        min_width (int | None): Minimum desired width of the image. Ensures image width is at least this value.
            If not specified, pad_width_divisor must be provided.
        pad_height_divisor (int | None): If set, pads the image height to make it divisible by this value.
            If not specified, min_height must be provided.
        pad_width_divisor (int | None): If set, pads the image width to make it divisible by this value.
            If not specified, min_width must be provided.
        position (Literal["center", "top_left", "top_right", "bottom_left", "bottom_right", "random"]):
            Position where the image is to be placed after padding. Default is 'center'.
        border_mode (int): Specifies the border mode to use if padding is required.
            The default is `cv2.BORDER_REFLECT_101`.
        value (int, float, list[int], list[float] | None): Value to fill the border pixels if
            the border mode is `cv2.BORDER_CONSTANT`. Default is None.
        mask_value (int, float, list[int], list[float] | None): Similar to `value` but used for padding masks.
            Default is None.
        p (float): Probability of applying the transform. Default is 1.0.

    Targets:
        image, mask, bboxes, keypoints

    Image types:
        uint8, float32

    Note:
        - Either `min_height` or `pad_height_divisor` must be set, but not both.
        - Either `min_width` or `pad_width_divisor` must be set, but not both.
        - If `border_mode` is set to `cv2.BORDER_CONSTANT`, `value` must be provided.
        - The transform will maintain consistency across all targets (image, mask, bboxes, keypoints).
        - For bounding boxes, the coordinates will be adjusted to account for the padding.
        - For keypoints, their positions will be shifted according to the padding.

    Example:
        >>> import albumentations as A
        >>> transform = A.Compose([
        ...     A.PadIfNeeded(min_height=1024, min_width=1024, border_mode=cv2.BORDER_CONSTANT, value=0),
        ... ])
        >>> transformed = transform(image=image, mask=mask, bboxes=bboxes, keypoints=keypoints)
        >>> padded_image = transformed['image']
        >>> padded_mask = transformed['mask']
        >>> adjusted_bboxes = transformed['bboxes']
        >>> adjusted_keypoints = transformed['keypoints']
    

Parameters

• min_height: int | None (default: 1024)
• min_width: int | None (default: 1024)
• pad_height_divisor: int | None (default: null)
• pad_width_divisor: int | None (default: null)
• position: Literal['center', 'top_left', 'top_right', 'bottom_left', 'bottom_right', 'random'] (default: 'center')
• border_mode: Literal['cv2.BORDER_CONSTANT', 'cv2.BORDER_REPLICATE', 'cv2.BORDER_REFLECT', 'cv2.BORDER_WRAP', 'cv2.BORDER_DEFAULT', 'cv2.BORDER_TRANSPARENT'] (default: 4)
• value: float | Sequence[float] | None (default: null)
• mask_value: float | Sequence[float] | None (default: null)
• p: float (default: 1)

Targets

• Image
• Mask
• BBoxes
• Keypoints